draft-ietf-nntpext-base-13.txt   draft-ietf-nntpext-base-14.txt 
INTERNET DRAFT S. Barber INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services Expires: May 15, 2002 Academ Consulting Services
March 2001 November 2001
Network News Transport Protocol
draft-ietf-nntpext-base-13.txt Network News Transport Protocol
draft-ietf-nntpext-base-14.txt
1. Status of this Document 1. Status of this Document
This document is an Internet-Draft and is in full conformance This document is an Internet-Draft and is in full conformance with
with Section 10 of RFC 2026. Internet-Drafts are working Section 10 of RFC 2026. Internet-Drafts are working documents of the
documents of the Internet Engineering Task Force (IETF), its Internet Engineering Task Force (IETF), its areas, and its working
areas, and its working groups. Note that other groups may groups. Note that other groups may also distribute working documents
also distribute working documents as Internet-Drafts. as Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six
months and may be updated, replaced, or made obsolete by other Internet-Drafts are draft documents valid for a maximum of six months
documents at any time. It is inappropriate to use Internet- and may be updated, replaced, or made obsolete by other documents at
Drafts as reference material or to cite them other than as any time. It is inappropriate to use Internet-Drafts as reference
"work in progress." material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accesses at The list of current Internet-Drafts can be accesses at
http://www.ietf.org/ietf/1id-abstracts.txt. http://www.ietf.org/ietf/1id-abstracts.txt.
The list of Internet-Draft shadow directories can be accessed
at http://www.ietf.org/shadow.html.
This section will be updated with the appropriate verbiage The list of Internet-Draft shadow directories can be accessed at
from RFC 2223 should this document has been found ready for http://www.ietf.org/shadow.html.
publication as an RFC.
This document is a product of the NNTP Working Group, chaired This section will be updated with the appropriate verbiage from RFC
by Ned Freed and Stan Barber. 2223 should this document has been found ready for publication as an
RFC.
This document is a product of the NNTP Working Group, chaired by Ned
Freed and Stan Barber.
2. Abstract 2. Abstract
The Network News Transport Protocol has been in use in the The Network News Transport Protocol has been in use in the Internet
Internet for a decade and remains one of the most popular for a decade and remains one of the most popular protocols (by volume)
protocols (by volume) in use today. This document is a in use today. This document is a replacement for RFC 977 and
replacement for RFC 977 and officially updates the protocol officially updates the protocol specification. It clarifies some
specification. It clarifies some vagueness in RFC 977, vagueness in RFC 977, includes some new base functionality and
includes some new base functionality and provides a specific provides a specific mechanism to add standardized extensions to NNTP.
mechanism to add standardized extensions to NNTP.
3. Introduction 3. Introduction
This document specifies the Network News Transport Protocol This document specifies the Network News Transport Protocol (NNTP),
(NNTP), which is used for the distribution, inquiry, which is used for the distribution, inquiry, retrieval, and posting of
retrieval, and posting of net news articles using a reliable net news articles using a reliable stream-based mechanism. For news
stream-based mechanism. For news reading clients, NNTP enables reading clients, NNTP enables retrieval of news articles that are
retrieval of news articles that are stored in a central stored in a central database, giving subscribers the ability to select
only those articles they wish to read.
Barber [Page 1]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
database, giving subscribers the ability to select only those
articles they wish to read.
The netnews model provides for indexing, cross-referencing, The netnews model provides for indexing, cross-referencing, and
and expiration of aged messages. For server-to-server expiration of aged messages. For server-to-server interaction, NNTP is
interaction, NNTP is designed for efficient transmission of designed for efficient transmission of net news articles over a
net news articles over a reliable full duplex communication reliable full duplex communication method.
method.
Every attempt is made to insure that the protocol Every attempt is made to insure that the protocol specification in
specification in this document is compatible with the version this document is compatible with the version specified in RFC
specified in RFC 977[1]. However, this version does not 977[[1]. However, this version does not support the ill-defined SLAVE
support the ill-defined SLAVE command and permits four digit command and permits four digit years to be specified in the NEWNEWS
years to be specified in the NEWNEWS and NEWGROUPS commands. and NEWGROUPS commands. It changes the default character set to
It changes the default character set to UTF-8[2] instead of UTF-8[2] instead of US-ASCII[3]. It also extends the newsgroup
US-ASCII[3]. It also extends the newsgroup name matching name matching capabilities already documented in RFC 977.
capabilities already documented in RFC 977.
Generally, new functionality is available using new keywords. Generally, new functionality is available using new keywords. Part of
Part of that new functionality involves a mechanism to that new functionality involves a mechanism to discover what new
discover what new functionality is available to clients from a functionality is available to clients from a server.
server. This mechanism can also be used to add more functionality as needs
merit such additions.
This mechanism can also be used to add more functionality as The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
needs merit such additions. "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119[4].
An implementation is not compliant if it fails to satisfy one or more
of the MUST requirements for this protocol. An implementation that
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL Barber Page [1]
NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described
in RFC 2119[4].
An implementation is not compliant if it fails to satisfy one INTERNET DRAFT S. Barber
or more of the MUST requirements for this protocol. An Expires: May 15, 2002 Academ Consulting Services
implementation that satisfies all the MUST and all the SHOULD November 2001
requirements for its protocols is said to be "unconditionally satisfies all the MUST and all the SHOULD requirements for its
compliant"; one that satisfies all the MUST requirements but protocols is said to be "unconditionally compliant"; one that
not all the SHOULD requirements for NNTP is said to be satisfies all the MUST requirements but not all the SHOULD
"conditionally compliant". requirements for NNTP is said to be "conditionally compliant".
For the remainder of this memo, the term "client host" refers For the remainder of this memo, the term "client host" refers to a
to a host making use of the NNTP service, while the term host making use of the NNTP service, while the term "server host"
"server host" refers to a host that offers the NNTP service. refers to a host that offers the NNTP service. In addition, where
examples of interactions between a client host and a server host are
provided a "[C]" will be used to represent the client host and a "[S]"
will be used to represent the server host.
In addition, where examples of interactions between a client For the remainder of this memo, responses will be described in tables
host and a server host are provided a "[C]" will be used to listing the required format of a response followed by the meaning that
represent the client host and a "[S]" will be used to should be ascribed to that response.
represent the server host.
4. Basic Operation. 4. Basic Operation.
Every NNTP session MUST involve the following in this order: Every NNTP session MUST involve the following in this order:
Barber [Page 2]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
CONNECTION CONNECTION
GREETING GREETING
DISCONNECTION DISCONNECTION
Other steps may occur between the GREETING and DISCONNECTION Other steps may occur between the GREETING and DISCONNECTION step.
step. They are:
They are:
CAPABILITIES DISCOVERY CAPABILITIES DISCOVERY
NEWS EXCHANGE NEWS EXCHANGE
CONCLUSION CONCLUSION
NNTP operates over any reliable data stream 8-bit-wide NNTP operates over any reliable data stream 8-bit-wide channel. When
channel. When running over TCP/IP, the official port for the running over TCP/IP, the official port for the NNTP service is 119.
NNTP service is 119. Initially, the server host starts the Initially, the server host starts the NNTP service by listening on a
NNTP service by listening on a TCP port. When a client host TCP port. When a client host wishes to make use of the service, it
wishes to make use of the service, it MUST establish a TCP MUST establish a TCP connection with the server host by connecting to
connection with the server host by connecting to that host on that host on the same port on which the server is listening. This is
the same port on which the server is listening. This is the the CONNECTION step. When the connection is established, the NNTP
CONNECTION step. When the connection is established, the NNTP server host MUST send a greeting. This is the GREETING step. The
server host MUST send a greeting. This is the GREETING step. client host and server host SHOULD then exchange commands and
The client host and server host SHOULD then exchange commands responses (respectively) until the connection is closed or aborted.
and responses (respectively) until the connection is closed or
aborted. This final step is called the DISCONNECTION step.
This final step is called the DISCONNECTION step.
If there is a CONCLUSION step, it MUST immediately precede the If there is a CONCLUSION step, it MUST immediately precede the
DISCONNECTION step. There MUST be only one CONNECTION, DISCONNECTION step. There MUST be only one CONNECTION, CONCLUSION and
CONCLUSION and DISCONNECTION step for each NNTP session. All DISCONNECTION step for each NNTP session. All other steps MAY be
other steps MAY be repeated as needed. For example, the repeated as needed. For example, the GREETING step may be repeated if
GREETING step may be repeated if the client makes use of the the client makes use of the MODE READER command (See Section 7.2 for
MODE READER command (See Section 7.2 for more on the MODE more on the MODE READER command).
READER command).
The character set for all NNTP commands is UTF-8. Commands in The character set for all NNTP commands is UTF-8. Commands in the NNTP
the NNTP MUST consist of an US-ASCII case-insensitive keyword, MUST consist of an US-ASCII case-insensitive keyword, which MAY be
which MAY be followed by one or more arguments. An US-ASCII followed by one or more arguments. An US-ASCII CRLF pair MUST
CRLF pair MUST terminate all commands. Multiple commands MUST terminate all commands. Multiple commands MUST NOT be on the same
NOT be on the same line. Keywords MUST consist of printable line. Keywords MUST consist of printable US-ASCII characters. Unless
US-ASCII characters. Unless otherwise noted elsewhere in this otherwise noted elsewhere in this document, arguments SHOULD consist
document, arguments SHOULD consist of printable US-ASCII of printable US-ASCII characters. Keywords and arguments MUST be each
characters. Keywords and arguments MUST be each separated by separated by one or more US-ASCII SPACE or US-ASCII TAB characters.
one or more US-ASCII SPACE or US-ASCII TAB characters. Keywords MUST be at least three US-ASCII characters and MUST NOT
Keywords MUST be at least three US-ASCII characters and MUST exceed 12 US-ASCII characters. Command lines MUST NOT exceed 512
NOT exceed 12 US-ASCII characters. Command lines MUST NOT octets, which includes the terminating US-ASCII CRLF pair. Arguments
exceed 512 octets, which includes the terminating US-ASCII MUST NOT exceed 497 octets.
CRLF pair. Arguments MUST NOT exceed 497 octets.
Each response MUST start with a three-digit response code that Each response MUST start with a three-digit response code that is
is sufficient to distinguish all responses. Certain valid sufficient to distinguish all responses. Certain valid responses are
responses are defined to be multi-line; for all others, the defined to be multi-line; for all others, the response is contained in
response is contained in a single line. All multi-line a single line. All multi-line responses MUST adhere to the following
format:
Barber [Page 3] 1. The repsonse consists of a sequence of one or more "lines", each
being a stream of octets ending with 0x0D 0x0A (US-ASCII CRLF).
Apart from those line endings, the stream MUST NOT include the
octets 0x00, 0x0A, or 0x0D (US-ASCII NUL, LF, and CR).
Barber Page [2]
INTERNET DRAFT S. Barber INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services Expires: May 15, 2002 Academ Consulting Services
March 2001 November 2001
responses MUST adhere to the following format: After sending 2. The first such line contains the response code as with a single
the first line of the response and an US-ASCII CRLF, any line response.
additional lines are sent, each terminated by an US-ASCII CRLF 3. If any subsequent line begins with the "termination octet" (0x2E
pair. When all lines of the response have been sent, a final or US_ASCII "."), that line MUST be "byte-stuffed" by pre-pending an
line MUST be sent, consisting of a termination octet (US-ASCII additional termination octet (0x2E) to that line of the response.
decimal code 046, ".") and an US-ASCII CRLF pair. If any line 4. The lines of the response MUST be followed by a terminating line
of the multi-line response begins with the termination octet, consisting of a single termination octet (0x2E or US_ASCII
the line MUST be "byte-stuffed" by pre-pending the termination ".")followed by CRLF in the normal way. Thus a multi-line response
octet to that line of the response. Hence, a multi-line is always terminated with the five octets "CRLF.CRLF" (in US-ASCII).
response is terminated with the five octets "CRLF.CRLF" (in 5. There is NO limit on the length of a line.
US-ASCII). When examining a multi-line response, the client 6. When interpreting a multi-line response, the "byte stuffing" MUST
MUST check to see if the line begins with the termination be undone; i.e. the client MUST ensure that, in any line beginning
octet. If so and if octets other than US-ASCII CRLF follow, with the termination octet followed by octets other than US-ASCII
the first octet of the line (the termination octet) MUST be CRLF, that initial termination octet is disregarded.
stripped away. If so and if US-ASCII CRLF immediately follows 7. Likewise, the terminating line ".CRLF" (in US-ASCII) MUST NOT be
the termination character, then the response from the NNTP considered part of the multi-line response; i.e. the client MUST
server is ended and the line containing ".CRLF" (in US-ASCII) ensure that any line beginning with the termination octet followed
MUST NOT be considered part of the multi-line response. Where immediately by US-ASCII CRLF is disregarded; (the first CRLF of the
a response is multi-line, the description of the command will terminating "CRLF.CRLF" is, of course, part of the last line of the
define the format of the response before "byte-stuffing" takes response).
place.
An NNTP server MAY have an inactivity autologout timer. Such a NOTE: Texts using encodings (such as UTF-16 or UTF-32) that may
timer MUST be of at least three minutes duration. The receipt contain the NUL octet or the CR or LF octets in contexts other than
of any command from the client during that interval SHOULD the CRLF line ending cannot be reliably conveyed in the above format.
suffice to reset the autologout timer. When the timer Note also that, although this standard does not limit the length of a
expires, the server should close the TCP connection without line in any way, the standards that define the format of articles may
sending any response to the client. do so.
An NNTP server MAY have an inactivity autologout timer. Such a timer
SHOULD be of at least three minutes duration, with the exception that
there MAY be a shorter limit on how long the server is willing to wait
for the first command from the client. The receipt of any command
from the client during the timer interval SHOULD suffice to reset the
autologout timer. Similarly, the receipt of any significant amount of
data from the client while in the midst of sending a multilane message
to the server (such as during a POST or IHAVE command) SHOULD suffice
to reset the autologout timer. When the timer expires, the server
SHOULD close the TCP connection without sending any response to the
client, including when the client is in the middle of sending a
multi-line message to the server.
4.1 Response Codes 4.1 Response Codes
Each response MUST begin with a three-digit status indicator. Each response MUST begin with a three-digit status indicator. These
These are status reports from the server and indicate the are status reports from the server and indicate the response to the
response to the last command received from the client. last command received from the client.
The first digit of the response broadly indicates the success, The first digit of the response broadly indicates the success,
failure, or progress of the previous command. failure, or progress of the previous command.
1xx - Informative message 1xx - Informative message
2xx - Command ok 2xx - Command ok
3xx - Command ok so far, send the rest of it. 3xx - Command ok so far, send the rest of it.
4xx - Command was correct, but couldn't be performed for some 4xx - Command was correct, but couldn't be performed for some reason.
reason. 5xx - Command unimplemented, or incorrect, or a serious program error
5xx - Command unimplemented, or incorrect, or a serious occurred.
program error occurred.
The next digit in the code indicates the function response
category.
The next digit in the code indicates the function response category.
x0x - Connection, setup, and miscellaneous messages x0x - Connection, setup, and miscellaneous messages
Barber [Page 4]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
x1x - Newsgroup selection x1x - Newsgroup selection
x2x - Article selection x2x - Article selection
x3x - Distribution functions x3x - Distribution functions
x4x - Posting x4x - Posting
x8x - Reserved for authentication and authorization extensions x8x - Reserved for authentication and authorization extensions
x9x - Reserved for private use (non-standard extensions) x9x - Reserved for private use (non-standard extensions)
Certain responses contain parameters such as numbers and names Certain responses contain parameters such as numbers and names in
in addition to the status indicator. In those cases, the addition to the status indicator. In those cases, the number and type
number and type of such parameters is fixed for each response of such parameters is fixed for each response code to simplify
code to simplify interpretation by the client (any extension interpretation by the client (any extension MUST follow this principle
MUST follow this principle as well). In all other cases, the as well). In all other cases, the client MUST only use the status
client MUST only use the status indicator itself to determine indicator itself to determine the nature of the response. The exact
the nature of the response. The exact response codes that can
be returned in response to a given command are detailed in the
description of the keyword that is the first part of the
command.
Parameters MUST be separated from the numeric status indicator Barber Page [3]
and from each other by a single US-ASCII space. All numeric
parameters MUST be in base 10 (decimal) format, and MAY have
leading zeros. String parameters MUST contain at least one
character and MUST NOT contain US-ASCII spaces, CR, LF, or
tab). The server MAY add any text after the response code or
last parameter as appropriate, and the client MUST NOT make
decisions based on this text. Such text MUST be separated from
the numeric status indicator or the last parameter by at least
one US-ASCII space.
The server MUST respond to any command with the appropriate INTERNET DRAFT S. Barber
generic response (given in section 4.1.1) if it represents the Expires: May 15, 2002 Academ Consulting Services
situation. Otherwise, each recognized command MUST return one November 2001
of the response codes specifically listed in its description
or in an extension. A server MAY provide extensions to this
specification, including new commands, new features of
existing commands, and other ways of changing the internal
state of the server. However, the server MUST NOT produce any
other responses to a client that does not invoke any of the
additional features. (Therefore a client that restricts itself
to this specification will only receive the responses that are
listed).
Each recognized command MUST return 501 (as above) or one of response codes that can be returned in response to a given command are
the response codes specifically listed in its description or detailed in the description of the keyword that is the first part of
in an extension. A server MAY provide extensions to this the command.
specification, including new commands, new features of
existing commands, and other ways of changing the internal
state of the server. However, the server MUST NOT produce any
other responses to a client that does not invoke any of the
Barber [Page 5] Parameters MUST be separated from the numeric status indicator and
from each other by a single US-ASCII space. All numeric parameters
MUST be in base 10 (decimal) format, and MAY have leading zeros.
INTERNET DRAFT S. Barber String parameters MUST contain at least one character and MUST NOT
Expires: October 30, 2001 Academ Consulting Services contain US-ASCII spaces, CR, LF, or tab). The server MAY add any text
March 2001 after the response code or last parameter as appropriate, and the
additional features. (Therefore a client that restricts itself client MUST NOT make decisions based on this text. Such text MUST be
separated from the numeric status indicator or the last parameter by
at least one US-ASCII space.
The server MUST respond to any command with the appropriate generic
response (given in section 4.1.1) if it represents the situation.
Otherwise, each recognized command MUST return one of the response
codes specifically listed in its description or in an extension. A
server MAY provide extensions to this specification, including new
commands, new features of existing commands, and other ways of
changing the internal state of the server. However, the server MUST
NOT produce any other responses to a client that does not invoke any
of the additional features. (Therefore a client that restricts itself
to this specification will only receive the responses that are to this specification will only receive the responses that are
listed). listed).
If a client receives an unexpected response, it SHOULD use the If a client receives an unexpected response, it SHOULD use the first
first digit of the response to determine the result. For digit of the response to determine the result. For example, an
example, an unexpected 2xx should be taken as success and an unexpected 2xx should be taken as success and an unexpected 4xx or 5xx
unexpected 4xx or 5xx as failure. as failure.
Response codes not specified in this standard MAY be used for
any installation-specific additional commands also not
specified. These SHOULD be chosen to fit the pattern of x9x
specified above.
Neither this document nor any extension registered with IANA Response codes not specified in this standard MAY be used for any
(see section 12) will specify any response codes of the x9x installation-specific additional commands also not specified. These
pattern. (Implementers of extensions are accordingly cautioned SHOULD be chosen to fit the pattern of x9x specified above.
not to use such responses for extensions that may subsequently Neither this document nor any extension registered with IANA (see
be submitted for registration.) section 12) will specify any response codes of the x9x pattern.
(Implementers of extensions are accordingly cautioned not to use such
responses for extensions that may subsequently be submitted for
registration.)
4.1.1 Generic Response Codes 4.1.1 Generic Response Codes
The server MUST respond to any command with the appropriate The server MUST respond to any command with the appropriate one of the
one of the following generic responses if it represents the following generic responses if it represents the situation.
situation. If the command is not recognized, or it is an optional command or
extension that is not implemented by the server, the response code 500
If the command is not recognized, or it is an optional command MUST be returned.
or extension that is not implemented by the server, the
response code 500 MUST be returned.
If there is a syntax error in the arguments of a recognized If there is a syntax error in the arguments of a recognized command,
command, the response code 501 MUST be returned. Note that the response code 501 MUST be returned. Note that where a command has
where a command has variants depending on a keyword (e.g. LIST variants depending on a keyword (e.g. LIST ACTIVE and LIST
ACTIVE and LIST NEWSGROUPS), then 501 MUST be used when the NEWSGROUPS), then 501 MUST be used when the requested variant is not
requested variant is not implemented but the base command is. implemented but the base command is.
If the client is not authorized to use the specified facility If the client is not authorized to use the specified facility when the
when the server is in its current state, the response code 502 server is in its current state, the response code 502 MUST be
MUST be returned. A different command MIGHT change the server returned. A different command might change the server state and permit
state and permit the command if it is retried. the command if it is retried.
If the server does not provide an optional feature, then the If the server does not provide an optional feature, then the response
response code 403 MUST be returned if the omission is code 403 MUST be returned if the omission is temporary (e.g. because a
temporary (e.g. because a necessary facility is unavailable) necessary facility is unavailable) and the code 503 if it is
and the code 503 if it is permanent (e.g. because the server permanent (e.g. because the server does not store the required
does not store the required information). information).
If the server has to terminate the connection for some reason, If the server has to terminate the connection for some reason, it MUST
it MUST give a 400 response code to the next command and then give a 400 response code to the next command and then immediately
immediately close the TCP connection. It MAY give a 401 close the TCP connection. It MAY give a 401 response code to any
response code to any command to indicate that termination is command to indicate that termination is imminent (following a 401
response, it MUST NOT close the TCP connection immediately).
Barber [Page 6] 5. The WILDMAT format
INTERNET DRAFT S. Barber The WILDMAT format[5] described here is based on the version first
Expires: October 30, 2001 Academ Consulting Services
March 2001
imminent (following a 401 response, it MUST NOT close the TCP
connection immediately).
5. The WILDMAT format Barber Page [4]
The WILDMAT format[5] described here is based on the version INTERNET DRAFT S. Barber
first developed by Rich Salz which was derived from the format Expires: May 15, 2002 Academ Consulting Services
used in the UNIX "find" command to articulate file names. It November 2001
was developed to provide a uniform mechanism for matching developed by Rich Salz which was derived from the format used in the
patterns in the same manner that the UNIX shell matches UNIX "find" command to articulate file names. It was developed to
filenames. Patterns are implicitly anchored at the beginning provide a uniform mechanism for matching patterns in the same manner
and end of each string when testing for a match. There are that the UNIX shell matches filenames. Patterns are implicitly
five pattern-matching operations other than a strict one-to- anchored at the beginning and end of each string when testing for a
one match between the pattern and the source to be checked for match. There are five pattern-matching operations other than a strict
a match. The first is an asterisk (*) to match any sequence of one-to-one match between the pattern and the source to be checked for
zero or more UTF-8 characters. The second is a question mark a match. The first is an asterisk (*) to match any sequence of zero or
(?) to match any single UTF-8 character. The third specifies a more UTF-8 characters. The second is a question mark (?) to match any
specific set of characters. The set is specified as a list of single UTF-8 character. The third specifies a specific set of
characters, or as a range of characters where the beginning characters. The set is specified as a list of characters, or as a
and end of the range are separated by a minus (or dash) range of characters where the beginning and end of the range are
character, or as any combination of lists and ranges. The dash separated by a minus (or dash) character, or as any combination of
can also be included in the set as a character it if is the lists and ranges. The dash can also be included in the set as a
beginning or end of the set. This set is enclosed in square character it if is the beginning or end of the set. This set is
brackets. The close square bracket (]) may be used in a set if enclosed in square brackets. The close square bracket (]) may be used
it is the first character in the set. The fourth operation is in a set if it is the first character in the set. The fourth operation
the same as the logical not of the third operation and is is the same as the logical not of the third operation and is specified
specified the same way as the third with the addition of a the same way as the third with the addition of a caret character (^)
caret character (^) at the beginning of the test string just at the beginning of the test string just inside the open square
inside the open square bracket. The final operation uses the bracket. The final operation uses the backslash character to
backslash character to invalidate the special meaning of the invalidate the special meaning of the open square bracket ([), the
open square bracket ([), the asterisk, backslash, or the asterisk, backslash, or the question mark. Two backslashes in sequence
question mark. Two backslashes in sequence will result in the will result in the evaluation of the backslash as a character with no
evaluation of the backslash as a character with no special special meaning.
meaning.
Implementers must be careful to apply the pattern-matching Implementers must be careful to apply the pattern-matching operators
operators to whole characters encoded in UTF-8, and not to to whole characters encoded in UTF-8, and not to individual octets.
individual octets.
5.1 Negating the wildmat pattern 5.1 Negating the wildmat pattern
The exclamation point can be used at the beginning of a The exclamation point can be used at the beginning of a wildmat to
wildmat to negate it. That is, if the remainder of the pattern negate it. That is, if the remainder of the pattern would match the
would match the string then the negated pattern does not, and string then the negated pattern does not, and vice versa. If it
vice versa. If it appears as any other character other than appears as any other character other than the first one, it has no
the first one, it has no special meaning. special meaning.
Barber [Page 7]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
5.2 Examples 5.2 Examples
a) [^]-] -- matches any single character other than a [^]-] matches any single character other than
close square bracket or a minus sign/dash. a close square bracket or a minus
b) *bdc -- matches any string that ends with the string sign/dash
"bdc" including the string "bdc" (without quotes). *bdc matches any string that ends with the
c) [0-9a-zA-Z] -- matches any single printable string "bdc" including the string "bdc"
alphanumeric ASCII character. (without quotes)
d) a??d -- matches any four character string which [0-9a-zA-Z] matches any single printable
begins with a and ends with d. alphanumeric ASCII character
e)!bc*d -- matches any string that does not start with a??d matches any four character string which
"bc" and end with "d" (without quotes) begins with a and ends with d
f)!\\x -- matches any string that does not start with !bc*d matches any string that does not start
"\x" (without quotes) with "bc" and end with "d" (without
quotes)
!\\x matches any string that does not start
with "\x" (without quotes)
6. Format for Keyword Descriptions 6. Format for Keyword Descriptions
On the following pages are descriptions of each keyword On the following pages are descriptions of each keyword recognized by
recognized by the NNTP server and the responses that will be the NNTP server and the responses that will be returned by those
returned by those commands. These keywords are grouped by the commands. These keywords are grouped by the functional step in which
functional step in which they are used. they are used.
Each keyword is shown in upper case for clarity, although the NNTP
Each keyword is shown in upper case for clarity, although the server ignores case in the interpretation of commands.
NNTP server ignores case in the interpretation of commands.
Parameters are shown as follows: Parameters are shown as follows:
o UPPERCASE indicates literal text to be included in the
. UPPERCASE indicates literal text to be included in the
command; command;
. lowercase indicates a token described elsewhere; o lowercase indicates a token described elsewhere;
. [brackets] indicate that the parameter is optional;
. ellipsis... indicates that the parameter may be repeated Barber Page [5]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
o [brackets] indicate that the parameter is optional;
o ellipsis... indicates that the parameter may be repeated
any number of times (it must occur at least once); any number of times (it must occur at least once);
. vertical|bar indicates a choice of two mutually exclusive o vertical|bar indicates a choice of two mutually exclusive
parameters (exactly one must be provided). parameters (exactly one must be provided).
Parameters are case or language specific only when specified Parameters are case or language specific only when specified (either
(either in this document or in RFC 1036[6]). in this document or in RFC 1036[6]).
The name "wildmat" for a parameter indicates that it is a The name "wildmat" for a parameter indicates that it is a wildmat
wildmat format pattern as defined in section 5. format pattern as defined in section 5.
7. The GREETING Step 7. The GREETING Step
7.1 Initial Connection 7.1 Initial Connection
There is no keyword presented by the client upon initial There is no keyword presented by the client upon initial connection to
connection to the server. The server MUST present an the server. The server MUST present an appropriate response code as a
appropriate response code as a greeting to the client. This greeting to the client. This response informs the client about what
steps the client should take to reach the news exchange step.
If the server will accept further commands from the client including
POST, the server MUST present a 200 greeting code.
Barber [Page 8] If the server will accept further commands from the client, but it is
not authorized to post articles using the POST command, the server
MUST present a 201 greeting code.
INTERNET DRAFT S. Barber Otherwise the server MUST present a 400 or 502 greeting code and then
Expires: October 30, 2001 Academ Consulting Services immediately close the connection. 502 MUST be used if the client is
March 2001 not permitted under any circumstances to interact with the server and
response informs the client about what steps the client should 400 otherwise.
take to reach the news exchange step.
If the server will accept further commands from the client 7.1.1 Responses
including POST, the server MUST present a 200 greeting code.
If the server will accept further commands from the client,
but it is not authorized to post articles using the POST
command, the server MUST present a 201 greeting code.
Otherwise the server MUST present a 400 or 502 greeting code 200 Service available, posting allowed
and then immediately close the connection. 502 MUST be used if 201 Service available, posting prohibited
the client is not permitted under any circumstances to 400 Service temporarily unavailable
interact with the server and 400 otherwise. 502 Service unavailable
7.1.1 Initial Connection Example Following a 400 or 502 response the server MUST immediately close the
connection.
7.1.2 Initial Connection Example
Example of a normal connection from an authorized client Example of a normal connection from an authorized client
[Initial TCP connection setup completed.] [Initial TCP connection setup completed.]
[C] Initial TCP connection completed [C] Initial TCP connection completed
[S] 200 NNTP Service Ready, posting permitted [S] 200 NNTP Service Ready, posting permitted
Client can send commands at this point. In this example, the Client can send commands at this point. In this example, the client
client jumps directly to the conclusion step (See section 10). jumps directly to the conclusion step (See section 10).
[C] QUIT [C] QUIT
[S] 205 NNTP Service exits normally [S] 205 NNTP Service exits normally
[Server closes connection.] [Server closes connection.]
Example of a normal connection from an unauthorized client Example of a normal connection from an unauthorized client
[C] Initial TCP connection completed [C] Initial TCP connection completed
[S] 502 NNTP Service Unavailable [S] 502 NNTP Service Unavailable
[Server closes connection.] [Server closes connection.]
Example of a normal connection from an authorized client that is not
Example of a normal connection from an authorized client that permitted to post
is not permitted to post
[Initial TCP connection setup completed.] [Initial TCP connection setup completed.]
[S] 201 NNTP Service Ready, posting prohibited [S] 201 NNTP Service Ready, posting prohibited
Client can send commands at this point. In this example, the
client jumps directly to the conclusion step (See section 10).
[C] QUIT
[S] 205 NNTP Service exits normally
[Server closes connection.]
Barber [Page 9] Barber Page[6]
INTERNET DRAFT S. Barber INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services Expires: May 15, 2002 Academ Consulting Services
March 2001 November 2001
Example of a connection from any client where the server is
unable to provide service Client can send commands at this point. In this example, the client
jumps directly to the conclusion step (See section 10).
[C] QUIT
[S] 205 NNTP Service exits normally
[Server closes connection.]
Example of a connection from any client where the server is unable to
provide service
[Initial TCP connection setup completed.] [Initial TCP connection setup completed.]
[S] 400 NNTP Service temporarily unavailable [S] 400 NNTP Service temporarily unavailable
[Server closes connection.] [Server closes connection.]
7.2 MODE READER 7.2 MODE READER
MODE READER MODE READER
MODE READER SHOULD be sent by any client that intends to use MODE READER SHOULD be sent by any client that intends to use any
any command other than IHAVE, HEAD, STAT, LIST, LIST command other than IHAVE, HEAD, STAT, LIST, LIST EXTENSIONS, or
EXTENSIONS, or commands advertised by the server as available commands advertised by the server as available via LIST EXTENSIONS.
via LIST EXTENSIONS. Servers MAY require that this command be issued before any other
commands are sent and MAY reject any other commands until after a MODE
Servers MAY require that this command be issued before any READER command has been sent.
other commands are sent and MAY reject any other commands
until after a MODE READER command has been sent.
The server MUST present a response using the same codes as the The server MUST present a response using the same codes as the
initial greeting (as described in section 7.1) to indicate its initial greeting (as described in section 7.1) to indicate its
ability to provide reading service to the client. ability to provide reading service to the client.
Clients SHOULD wait for a response to MODE READER after Clients SHOULD wait for a response to MODE READER after sending this
sending this command and SHOULD NOT send any additional command and SHOULD NOT send any additional commands until that
commands until that response has been received from the response has been received from the server.
server.
Once MODE READER is sent, IHAVE (and any extensions intended Once MODE READER is sent, IHAVE (and any extensions intended for
for peer-to-peer article transfer) MAY no longer be permitted, peer-to-peer article transfer) MAY no longer be permitted, even if it
even if it were permitted before the MODE READER command. The were permitted before the MODE READER command. The results of LIST
results of LIST EXTENSIONS MAY be different following a EXTENSIONS MAY be different following a MODE READER command than prior
MODE READER command than prior to the issuing of that command. to the issuing of that command.
Servers are encouraged to not require this command even though
clients SHOULD send it when appropriate. It is present to Servers are encouraged to not require this command even though clients
support some news architectures that switch between modes SHOULD send it when appropriate. It is present to support some news
based on whether a given connection is a peer-to-peer architectures that switch between modes based on whether a given
connection with another server or a news reading client. connection is a peer-to-peer connection with another server or a news
reading client.
7.2.1 Responses 7.2.1 Responses
200 Posting Permitted 200 Posting permitted
201 Posting Not Permitted 201 Posting prohibited
400 Service temporarily unavailable 400 Service temporarily unavailable
502 Service unavailable 502 Service unavailable
Following a 400 or 502 response the server MUST immediately Following a 400 or 502 response the server MUST immediately close the
close the connection. connection.
Note that the response need not be the same as the one presented
Barber [Page 10] during the initial greeting.
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
Note that the response need not be the same as the one
presented during the initial greeting.
7.2.2 MODE READER Examples 7.2.2 MODE READER Examples
Example of use of the MODE READER command by an authorized Example of use of the MODE READER command by an authorized client
client
[C] MODE READER [C] MODE READER
[S] 200 NNTP Service Ready, posting permitted [S] 200 NNTP Service Ready, posting permitted
Client can send commands at this point. In this example, the Client can send commands at this point. In this example, the client
client jumps directly to the conclusion step (See section 10). jumps directly to the conclusion step (See section 10).
[C] QUIT [C] QUIT
[S] 205 NNTP Service exits normally [S] 205 NNTP Service exits normally
[Server closes connection.] [Server closes connection.]
Example of use of MODE READER by a client not authorized to Barber Page[7]
receive service from the server as a news reader
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
Example of use of MODE READER by a client not authorized to receive
service from the server as a news reader
[C] MODE READER [C] MODE READER
[S] 502 Service Unavailable [S] 502 Service Unavailable
[Server closes connection.] [Server closes connection.]
Example of a normal connection from an authorized client that Example of a normal connection from an authorized client that is not
is not permitted to post permitted to post
[C] MODE READER [C] MODE READER
[S] 201 NNTP Service Ready, posting prohibited [S] 201 NNTP Service Ready, posting prohibited
Client can send commands at this point. In this example, the client
Client can send commands at this point. In this example, the jumps directly to the conclusion step (See section 10).
client jumps directly to the conclusion step (See section 10).
[C] QUIT [C] QUIT
[S] 205 NNTP Service exits normally [S] 205 NNTP Service exits normally
[Server closes connection.] [Server closes connection.]
Example of a connection from any client where the server is Example of a connection from any client where the server is unable to
unable to provide news reader service provide news reader service
[C] MODE READER [C] MODE READER
[S] 400 NNTP Service temporarily unavailable [S] 400 NNTP Service temporarily unavailable
[Server closes connection.] [Server closes connection.]
Barber [Page 11]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
8. The CAPABILITIES DISCOVERY Step 8. The CAPABILITIES DISCOVERY Step
To discover what extensions are available, an NNTP client can To discover what extensions are available, an NNTP client can query
query the server with the LIST EXTENSIONS command. the server with the LIST EXTENSIONS command.
If a particular extension is unavailable, the client can If a particular extension is unavailable, the client can attempt to
attempt to work around it or it may wish to terminate the work around it or it may wish to terminate the session.
session.
See section 12 for further discussion of extensions. See section 12 for further discussion of extensions.
8.1 LIST EXTENSIONS 8.1 LIST EXTENSIONS
The LIST EXTENSIONS command allows a client to determine which The LIST EXTENSIONS command allows a client to determine which
extensions are supported by the server. extensions are supported by the server.
To discover what extensions are available, an NNTP client To discover what extensions are available, an NNTP client SHOULD query
SHOULD query the server early in the session for extensions the server early in the session for extensions information by issuing
information by issuing the LIST EXTENSIONS command. This the LIST EXTENSIONS command. This command MAY be issued at anytime
command MAY be issued at anytime during a session. It is not during a session. It is not required that the client issues this
required that the client issues this command before attempting command before attempting to make use of any extension. The response
to make use of any extension. The response generated by this generated by this command MAY change during a session because of other
command MAY change during a session because of other state state information. However, an NNTP client MUST NOT cache (for use in
information. However, an NNTP client MUST NOT cache (for use another session) any information returned if the LIST EXTENSIONS
in another session) any information returned if the LIST command succeeds. That is, an NNTP client is only able to get the
EXTENSIONS command succeeds. That is, an NNTP client is only current and correct information concerning available extensions during
able to get the current and correct information concerning a session by issuing a LIST EXTENSIONS command during that session and
available extensions during a session by issuing a LIST processing that response.
EXTENSIONS command during that session and processing that
response.
A successful response starts with a 202 code and is followed A successful response starts with a 202 code and is followed by a list
by a list of extensions, one per line. Each line MUST begin of extensions, one per line. Each line MUST begin with an
with exactly one space followed by an extension-label and extension-label and optionally one or more parameters (separated by
optionally one or more parameters (separated by single single spaces). The extension-label and the meaning of the parameters
spaces). The extension-label and the meaning of the parameters
are specified as part of the definition of the extension. The are specified as part of the definition of the extension. The
extension-label MUST be in uppercase. extension-label MUST be in uppercase.
The server MUST NOT list the same extension twice in the The server MUST NOT list the same extension twice in the response, and
response, and MUST list all supported extensions. The order in MUST list all supported extensions. The order in which the extensions
which the extensions are listed is not significant. The server are listed is not significant. The server need not even consistently
need not even consistently return the same order. return the same order.
If the server does not support any extensions, it SHOULD
return a 402 failure response but MAY return an empty list
instead.
Barber [Page 12] Barber Page[8]
INTERNET DRAFT S. Barber INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services Expires: May 15, 2002 Academ Consulting Services
March 2001 November 2001
8.1.1 Responses
202 extension list follows (multiline) If the server does not support any extensions, it SHOULD return a 402
400 service about to terminate failure response but MAY return an empty list instead.
402 no extensions available
503 unable to list extensions
Following a 503 response an extension might still be 8.1.1 Responses
available, and the client MAY attempt to use it.
The LIST EXTENSIONS command is optional, and a server MAY 202 Extension list follows (multi-line response)
issue a 500 (unknown command) or 501 (syntax error) response 400 Service temporarily unavailable
to it. 402 Server has no extensions
500 Unknown Command
501 Syntax Error
502 Program error, function not performed
Following a 503 response an extension might still be available, and
the client MAY attempt to use it
The LIST EXTENSIONS command is optional, and a server MAY issue a 500
(unknown command) or 501 (syntax error) response to it.
8.1.1.1 LIST EXTENSIONS Examples 8.1.1.1 LIST EXTENSIONS Examples
Example of a successful response: Example of a successful response:
[C] LIST EXTENSIONS [C] LIST EXTENSIONS
[S] 202 Extensions supported: [S] 202 Extensions supported:
[S] OVER [S] OVER
[S] PAT [S] PAT
[S] LISTGROUP [S] LISTGROUP
[S] . [S] .
The particular extensions shown here are simply examples of The particular extensions shown here are simply examples of what might
what might be defined in other places, and no particular be defined in other places, and no particular meaning should be
meaning should be attributed to them. attributed to them.
Example where no extensions are available, using preferred Example where no extensions are available, using preferred
format: format:
[C] LIST EXTENSIONS [C] LIST EXTENSIONS
[S] 402 Server has no extensions [S] 402 Server has no extensions
Example where no extensions are available, using an empty Example where no extensions are available, using an empty list:
list:
[C] LIST EXTENSIONS [C] LIST EXTENSIONS
[S] 202 Extensions supported: [S] 202 Extensions supported:
[S] . [S] .
Barber [Page 13]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
9. The NEWS EXCHANGE Step 9. The NEWS EXCHANGE Step
During this step, two basic types of transactions occur: During this step, two basic types of transactions occur:
. article retrieval from the server o article retrieval from the server
. article posting to the server o article posting to the server
9.1 Article Retrieval 9.1 Article Retrieval
News reading clients have available a variety of mechanisms to News reading clients have available a variety of mechanisms to
retrieve articles via NNTP. The news articles are stored and retrieve articles via NNTP. The news articles are stored and indexed
indexed using three types of keys. One key is the message id using three types of keys. One key is the message id of an article.
of an article. According to RFC 1036, this identifier should According to RFC 1036, this identifier should be globally unique.
be globally unique. Another key is composed of the newsgroup
name and the article number within that newsgroup. That key
MUST be unique to a particular server (there will be only one
article with that number within a particular newsgroup), but
is not required to be globally unique. Additionally, because
the same article can be cross-posted to multiple newsgroups,
there may be multiple keys that point to the same article on
the same server. The final key is the arrival timestamp,
giving the time that the article arrived at the server.
The server MUST ensure that article numbers are issued in
order of arrival timestamp; that is, articles arriving later
MUST have higher numbers than those that arrive earlier. The
server SHOULD allocate the next sequential unused number to
each new article.
Article numbers MUST lie between 1 and 4,294,967,295 Another key is composed of the newsgroup name and the article number
inclusive. The client and server SHOULD NOT use leading zeroes within that newsgroup. That key MUST be unique to a particular server
in specifying article numbers, and MUST NOT use more than 16 (there will be only one article with that number within a particular
digits. In some situations, the value zero replaces an article newsgroup), but is not required to be globally unique. Additionally,
number to show some special situation. because the same article can be cross-posted to multiple newsgroups,
there may be multiple keys that point to the same article on the same
9.1.1 Article Retrieval by Newsgroup Name and Article Number Barber Page [9]
The following commands are used to set the current newsgroup INTERNET DRAFT S. Barber
name and the "current article pointer" which is used by other Expires: May 15, 2002 Academ Consulting Services
commands for article retrieval. At the start of an NNTP November 2001
session, both of these values are undefined. server. The final key is the arrival timestamp, giving the time that
the article arrived at the server.
9.1.1.1 GROUP The server MUST ensure that article numbers are issued in order of
arrival timestamp; that is, articles arriving later MUST have higher
numbers than those that arrive earlier. The server SHOULD allocate the
next sequential unused number to each new article.
GROUP ggg Article numbers MUST lie between 1 and 4,294,967,295 inclusive. The
client and server SHOULD NOT use leading zeroes in specifying article
numbers, and MUST NOT use more than 16 digits. In some situations, the
value zero replaces an article number to show some special situation.
The required parameter ggg is the name of the newsgroup to be 9.1.1 Article Retrieval by Newsgroup Name and Article Number
selected (e.g. "news.software.b"). A list of valid newsgroups
Barber [Page 14] The following commands are used to set the current newsgroup name and
the "current article pointer" which is used by other commands for
article retrieval. At the start of an NNTP session, both of these
values are undefined.
INTERNET DRAFT S. Barber 9.1.1.1 GROUP
Expires: October 30, 2001 Academ Consulting Services
March 2001
may be obtained by using the LIST keyword. See section 9.4
for more information on the LIST keyword.
The successful selection response will return the article GROUP ggg
numbers of the first and last articles in the group at the The required parameter ggg is the name of the newsgroup to be selected
moment of selection (these numbers are referred to as the (e.g. "news.software.b"). A list of valid newsgroups may be obtained
"reported low water mark" and the "reported high water mark"), by using the LIST keyword. See section 9.4 for more information on
and an estimate of the number of articles on file in the the LIST keyword.
group.
If the group is not empty, the estimate MUST be at least the The successful selection response will return the article numbers of
actual number of articles available, and MUST be no greater the first and last articles in the group at the moment of selection
than one more than the difference between the reported low and (these numbers are referred to as the "reported low water mark" and
high water marks. (Some implementations will actually count the "reported high water mark"), and an estimate of the number of
the number of articles on file. Others will just subtract the articles on file in the group.
low water mark from the high water mark and add one to get an
estimate.)
If the group is empty, one of the following three situations If the group is not empty, the estimate MUST be at least the actual
will occur. Clients MUST accept all three cases; servers MUST number of articles available, and MUST be no greater than one more
NOT represent an empty group in any other way. than the difference between the reported low and high water marks.
(Some implementations will actually count the number of articles on
file. Others will just subtract the low water mark from the high water
mark and add one to get an estimate.)
. The high water mark will be one less than the low water If the group is empty, one of the following three situations will
mark, and the estimated article count will be zero. occur. Clients MUST accept all three cases; servers MUST NOT represent
Servers SHOULD use this method to show an empty group. an empty group in any other way.
This is the only time that the high water mark can be o The high water mark will be one less than the low water
less than the low water mark. mark, and the estimated article count will be zero. Servers
. All three numbers will be zero. SHOULD use this method to show an empty group. This is the only
. The high water mark is greater than or equal to the low time that the high water mark can be less than the low water
mark.
o All three numbers will be zero.
o The high water mark is greater than or equal to the low
water mark; the estimated article count might be zero or water mark; the estimated article count might be zero or
non-zero; if non-zero, the same requirements apply as for non-zero; if non-zero, the same requirements apply as for a
a non-empty group. non-empty group.
The set of articles in a group may change after the GROUP The set of articles in a group may change after the GROUP command is
command is carried out. That is: carried out. That is:
o articles may be removed from the group
o articles may be reinstated in the group with the same
article number, but those articles MUST have numbers no less than
the reported low water mark (note that this is a reinstatement of
the previous article, not a new article reusing the number)
o new articles may be added with article numbers greater than
the reported high water mark (if an article that was the one with
the highest number has been removed, the next new article will
not have the number one greater than the reported high water
mark)
. articles may be removed from the group Except when the group is empty and all three numbers are zero,
. articles may be reinstated in the group with the same whenever a subsequent GROUP command for the same newsgroup is issued,
article number, but those articles MUST have numbers no
less than the reported low water mark (note that this is
a reinstatement of the previous article, not a new
article reusing the number)
. new articles may be added with article numbers greater
than the reported high water mark (if an article that was
the one with the highest number has been removed, the
next new article will not have the number one greater
than the reported high water mark)
Barber [Page 15] Barber Page [10]
INTERNET DRAFT S. Barber INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services Expires: May 15, 2002 Academ Consulting Services
March 2001 November 2001
Except when the group is empty and all three numbers are zero, either by the same client or a different client, the reported low
whenever a subsequent GROUP command for the same newsgroup is water mark in the response MUST be no less than that in any previous
issued, either by the same client or a different client, the response for that newsgroup sent to any client. The client may make
reported low water mark in the response MUST be no less than use of the low water mark to remove all remembered information about
that in any previous response for that newsgroup sent to any articles with lower numbers, as these will never recur. This includes
client. The client may make use of the low water mark to the situation when the high water mark is one less than the low water
remove all remembered information about articles with lower mark.
numbers, as these will never recur. This includes the
situation when the high water mark is one less than the low
water mark.
No similar assumption can be made about the high water mark, No similar assumption can be made about the high water mark, as this
as this can decrease if an article is removed, and then can decrease if an article is removed, and then increase again if it
increase again if it is reinstated or if new articles arrive. is reinstated or if new articles arrive.
When a valid group is selected by means of this command, the When a valid group is selected by means of this command, the
internally maintained "current article pointer" MUST be set to internally maintained "current article pointer" MUST be set to the
the first article in the group and the name of the current first article in the group and the name of the current newsgroup MUST
newsgroup MUST be set to the selected newsgroup name. If an be set to the selected newsgroup name. If an invalid group is
invalid group is specified, the previously selected group, if specified, the previously selected group, if any, and article MUST
any, and article MUST remain selected. If an empty newsgroup remain selected. If an empty newsgroup is selected, the "current
is selected, the "current article pointer" is in an article pointer" is in an indeterminate state and MUST NOT be used.
indeterminate state and MUST NOT be used.
The GROUP keyword (or the LISTGROUP keyword, if implemented) The GROUP keyword (or the LISTGROUP keyword, if implemented) MUST be
MUST be used by a client and a successful response received used by a client and a successful response received before the any
before the any other command is used that depends on having other command is used that depends on having the "current article
the "current article pointer" be valid. pointer" be valid.
If the group specified is not available on the server MUST return a
411 error code.
9.1.1.1.1 Responses 9.1.1.1.1 Responses
211 n f l s group selected 211 n l h ggg Group successfully selected (n =
(n = estimated number of articles in group, f = first estimated number of articles in the
article number in the group, l = last article number group, l = low water mark, h = high
in the group, s = name of the group.) water mark, ggg = name of the group
411 no such newsgroup 411 No such newsgroup
9.1.1.1.2 GROUP Examples 9.1.1.1.2 GROUP Examples
Example for a group known to the server Example for a group known to the server
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
Example for a group unknown to the server Example for a group unknown to the server
[C] GROUP example.is.sob.bradner.or.barber [C] GROUP example.is.sob.bradner.or.barber
Barber [Page 16]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
[S] 411 example.is.sob.bradner.or.barber is unknown [S] 411 example.is.sob.bradner.or.barber is unknown
9.1.1.2 LAST 9.1.1.2 LAST
LAST LAST
If the current newsgroup is valid, the internally maintained If the current newsgroup is valid, the internally maintained "current
"current article pointer" MUST be set to the previous article article pointer" MUST be set to the previous article in the current
in the current newsgroup. If already positioned at the first newsgroup. If already positioned at the first article of the
article of the newsgroup, an error message MUST be returned newsgroup, an error message MUST be returned and the current article
and the current article MUST remain selected. MUST remain selected.
There MAY be no previous article in the group, although the There MAY be no previous article in the group, although the current
current article number is not the reported low water mark. article number is not the reported low water mark. There MUST NOT be a
previous article when the current article number is the reported low
water mark.
There MUST NOT be a previous article when the current article Because articles can be removed and added, the results of multiple
number is the reported low water mark. LAST and NEXT commands MAY not be consistent over the life of a
particular NNTP session.
Because articles can be removed and added, the results of If successful, a response indicating the current article number and a
multiple LAST and NEXT commands MAY not be consistent over the message-id string MUST be returned. No article text is sent in
life of a particular NNTP session.
If successful, a response indicating the current article Barber Page [11]
number and a message-id string MUST be returned. No article
text is sent in response to this command. INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
response to this command.
9.1.1.2.1 Responses 9.1.1.2.1 Responses
223 n a article retrieved - request text separately (n = 223 n a Article found (n = number, a = message-id)
article number, a = unique article id) 412 No newsgroup selected
412 no newsgroup selected 420 Current article pointer is invalid
420 no current article has been selected 422 No previous article in this group
422 no previous article in this group
9.1.1.2.2 LAST Examples 9.1.1.2.2 LAST Examples
Example of a successful article retrieval using LAST Example of a successful article retrieval using LAST
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] NEXT [C] NEXT
[S] 223 3000237 <668929@domain.com> retrieved [S] 223 3000237 <668929@domain.com> retrieved
[C] LAST [C] LAST
[S] 223 3000234 <45223423@to.to> retrieved [S] 223 3000234 <45223423@to.to> retrieved
Barber [Page 17] Example of an attempt to retrieve an article without having selected a
group (via the GROUP command) first
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
Example of an attempt to retrieve an article without having
selected a group (via the GROUP command) first
[S] 200 NNTP Service ready [S] 200 NNTP Service ready
[C] LAST [C] LAST
[S] 412 no newsgroup selected [S] 412 no newsgroup selected
Example of an attempt to retrieve an article using the LAST Example of an attempt to retrieve an article using the LAST command
command when the current article pointer is pointing at the when the current article pointer is pointing at the first article in
first article in the group the group
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] LAST [C] LAST
[S] 422 No previous article to retrieve [S] 422 No previous article to retrieve
Example of an attempt to retrieve an article using the LAST Example of an attempt to retrieve an article using the LAST command
command when the current group selected is empty when the current group selected is empty
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP example.empty.newsgroup [C] GROUP example.empty.newsgroup
[S] 211 0 0 0 example.empty.newsgroup [S] 211 0 0 0 example.empty.newsgroup
[C] LAST [C] LAST
[S] 420 No current article selected [S] 420 No current article selected
9.1.1.3 NEXT 9.1.1.3 NEXT
NEXT NEXT
If the current newsgroup is valid, the internally maintained If the current newsgroup is valid, the internally maintained "current
"current article pointer" MUST be advanced to the next article article pointer" MUST be advanced to the next article in the current
in the current newsgroup. If no more articles remain in the newsgroup. If no more articles remain in the current group, an error
current group, an error message MUST be returned and the message MUST be returned and the current article MUST remain selected.
current article MUST remain selected. If successful, a response indicating the current article number and
the message-id string MUST be returned. No article text is sent in
response to this command.
If successful, a response indicating the current article Barber Page [12]
number and the message-id string MUST be returned. No article
text is sent in response to this command.
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
9.1.1.3.1 Responses 9.1.1.3.1 Responses
Barber [Page 18] 223 n a Article found (n = number, a = message-id)
412 No newsgroup selected
INTERNET DRAFT S. Barber 420 Current article pointer is invalid
Expires: October 30, 2001 Academ Consulting Services 421 No next article in this group
March 2001
223 n a article retrieved - request text separately (n =
article number, a = unique article id)
412 no newsgroup selected
420 no current article has been selected
421 no next article in this group
9.1.1.3.2 NEXT Examples 9.1.1.3.2 NEXT Examples
Example of a successful article retrieval using NEXT Example of a successful article retrieval using NEXT
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] NEXT [C] NEXT
[S] 223 3000237 <668929@domain.com> retrieved [S] 223 3000237 <668929@domain.com> retrieved
Example of an attempt to retrieve an article without having Example of an attempt to retrieve an article without having selected a
selected a group (via the GROUP command) first group (via the GROUP command) first
[S] 200 NNTP Service ready [S] 200 NNTP Service ready
[C] NEXT [C] NEXT
[S] 412 no newsgroup selected [S] 412 no newsgroup selected
Example of an attempt to retrieve an article using the NEXT Example of an attempt to retrieve an article using the NEXT command
command when the current article pointer is pointing at the when the current article pointer is pointing at the last article in
last article in the group the group
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] ARTICLE 3002322 [C] ARTICLE 3002322
[S] 220 3002322 <411@whitehouse.gov> retrieved [S] 220 3002322 <411@whitehouse.gov> retrieved
[S] Path: pathost!demo!whitehouse!not-for-mail [S] Path: pathost!demo!whitehouse!not-for-mail
[S] From: nobody@whitehouse.gov(Demo User) [S] From: nobody@whitehouse.gov(Demo User)
[S] Newsgroups: misc.test [S] Newsgroups: misc.test
[S] Subject: I am just a test article [S] Subject: I am just a test article
[S] Date: 6 Oct 1998 04:38:40 -0500 [S] Date: 6 Oct 1998 04:38:40 -0500
[S] Organization: The White House, Washington, DC [S] Organization: The White House, Washington, DC
[S] Message-ID: <411@whitehouse.gov> [S] Message-ID: <411@whitehouse.gov>
Barber [Page 19]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
[S] [S]
[S] This is just a test article. [S] This is just a test article.
[S] . [S] .
[C] NEXT [C] NEXT
[S] 422 No next article to retrieve [S] 421 No next article to retrieve
Example of an attempt to retrieve an article using the NEXT Example of an attempt to retrieve an article using the NEXT command
command when the current group selected is empty when the current group selected is empty
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP example.empty.newsgroup [C] GROUP example.empty.newsgroup
[S] 211 0 0 0 example.empty.newsgroup [S] 211 0 0 0 example.empty.newsgroup
Barber Page [13]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
[C] NEXT [C] NEXT
[S] 420 No current article selected [S] 420 No current article selected
9.2 Retrieval of Articles and Article Sections 9.2 Retrieval of Articles and Article Sections
The ARTICLE, BODY, HEAD, and STAT commands are very similar. The ARTICLE, BODY, HEAD, and STAT commands are very similar. They
They differ only in the parts of the article that are differ only in the parts of the article that are presented to the
presented to the client and in the successful response code. client and in the successful response code. The ARTICLE command is
described here in full, while the other commands are described in
The ARTICLE command is described here in full, while the other terms of the differences.
commands are described in terms of the differences.
An article, as defined by RFC 1036, consists of two parts: the An article, as defined by RFC 1036, consists of two parts: the article
article headers and the article body. When responding to one headers and the article body. When responding to one of these
of these commands, the server presents the entire article or commands, the server presents the entire article or appropriate part
appropriate part and does not attempt to alter or translate it and does not attempt to alter or translate it in any way.
in any way.
9.2.1 ARTICLE 9.2.1 ARTICLE
ARTICLE <message-id> ARTICLE <message-id>
ARTICLE [number] ARTICLE [number]
The ARTICLE command selects an article based on the arguments The ARTICLE command selects an article based on the arguments and
and presents the header, a blank line, and the body of that presents the header, a blank line, and the body of that article. The
article. The command has two forms. command has two forms.
In the first form, a message-id is specified (including the
angle brackets), and the server presents the article with that
message-id in its headers. In this case, the server MUST NOT
alter the "current article pointer". This is both to
Barber [Page 20]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
facilitate the presentation of articles that may be referenced
within another article being read, and because of the semantic
difficulties of determining the proper sequence and membership
of an article which may have been posted to more than one
newsgroup.
In the second form, an article number may be specified. If so,
and if there is an article with that number in the currently
selected group, the server MUST set the current article
pointer to that number.
Then, whether or not a number was specified, the article In the first form, a message-id is specified (including the angle
indicated by the current article pointer is presented to the brackets), and the server presents the article with that message-id in
client. its headers. In this case, the server MUST NOT alter the "current
article pointer". This is both to facilitate the presentation of
articles that may be referenced within another article being read, and
because of the semantic difficulties of determining the proper
sequence and membership of an article which may have been posted to
more than one newsgroup.
Note that a previously valid article number MAY become invalid In the second form, an article number may be specified. If so, and if
if the article has been removed. A previously invalid article there is an article with that number in the currently selected group,
number MAY become valid if the article has been reinstated, the server MUST set the current article pointer to that number.
but such an article number MUST be no less than the reported Then, whether or not a number was specified, the article indicated by
low water mark for that group. the current article pointer is presented to the client.
Note that a previously valid article number MAY become invalid if the
article has been removed. A previously invalid article number MAY
become valid if the article has been reinstated, but such an article
number MUST be no less than the reported low water mark for that
group.
The server MUST NOT change the currently selected group as a The server MUST NOT change the currently selected group as a result of
result of this command. The server MUST NOT change the current this command. The server MUST NOT change the current selected article
selected article except when an article number argument was except when an article number argument was provided and the article
provided and the article exists; in particular, it MUST NOT exists; in particular, it MUST NOT change it following an unsuccessful
change it following an unsuccessful response. response.
9.2.1.1 Responses 9.2.1.1 Responses
First form (message-id specified): First form (message-id specified):
220 0 a article retrieved and follows (multiline, a = 220 0 a Article follows (multi-line response, a =
unique article id) message-id)
430 no such article 430 No article found with that message-id
502 service unavailable 502 Program error, function not performed
Second form (optional article number specified): Second form (optional article number specified):
220 n a article retrieved and follows (multiline, n = 220 n a Article follows (multi-line response, n =
article number, a = unique article id) article number, a = message-id)
412 no newsgroup selected 412 No newsgroup selected
420 no current article selected 420 No current article selected
423 no such article number in this group 423 No such article in this newsgroup
502 service unavailable 502 Program error, function no performed
The 420 response only occurs if no article number has been
specified.
In the 220 response, the first parameter is 0 for the first
form and the article number (within the current group) for the
Barber [Page 21] Barber Page [14]
INTERNET DRAFT S. Barber INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services Expires: May 15, 2002 Academ Consulting Services
March 2001 November 2001
second form. The second parameter is the message-id of the
article (within angle brackets). This is taken from the
message-id header line of the article (required by RFC 1036).
If there is no such line, the message-id "<0>" MUST be used
instead (without the double quotes).
Since the message-id field is unique for each article, it may
be used by a client to skip duplicate displays of articles
that have been posted more than once, or to more than one
newsgroup.
The article headers and body are returned as a multiline The 420 response only occurs if no article number has been specified.
response following the initial response line. In the 220 response, the first parameter is 0 for the first form and
the article number (within the current group) for the second form. The
second parameter is the message-id of the article (within angle
brackets). This is taken from the message-id header line of the
article (required by RFC 1036). If there is no such line, the
message-id "<0>" MUST be used instead (without the double quotes).
Since the message-id field is unique for each article, it may be used
by a client to skip duplicate displays of articles that have been
posted more than once, or to more than one newsgroup.
The article headers and body are returned as a multilane response
following the initial response line.
9.2.1.2 Examples 9.2.1.2 Examples
Example of a successful retrieval of an article (using no article
Example of a successful retrieval of an article (using no number)
article number)
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] ARTICLE [C] ARTICLE
[S] 220 3000234 <45223423@to.to> [S] 220 3000234 <45223423@to.to>
[S] Path: pathost!demo!somewhere!not-for-mail [S] Path: pathost!demo!somewhere!not-for-mail
[S] From: nobody@nowhere.to (Demo User) [S] From: nobody@nowhere.to (Demo User)
[S] Newsgroups: misc.test [S] Newsgroups: misc.test
[S] Subject: I am just a test article [S] Subject: I am just a test article
[S] Date: 6 Oct 1998 04:38:40 -0500 [S] Date: 6 Oct 1998 04:38:40 -0500
skipping to change at line 1124 skipping to change at line 1040
[S] [S]
[S] This is just a test article. [S] This is just a test article.
[S] . [S] .
Example of a successful retrieval of an article by message-id Example of a successful retrieval of an article by message-id
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] ARTICLE <45223423@to.to> [C] ARTICLE <45223423@to.to>
[S] 220 0 <45223423@to.to> [S] 220 0 <45223423@to.to>
[S] Path: pathost!demo!somewhere!not-for-mail [S] Path: pathost!demo!somewhere!not-for-mail
[S] From: nobody@nowhere.to (Demo User) [S] From: nobody@nowhere.to (Demo User)
Barber [Page 22]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
[S] Newsgroups: misc.test [S] Newsgroups: misc.test
[S] Subject: I am just a test article [S] Subject: I am just a test article
[S] Date: 6 Oct 1998 04:38:40 -0500 [S] Date: 6 Oct 1998 04:38:40 -0500
[S] Organization: Nowhere, To [S] Organization: Nowhere, To
[S] Message-ID: <45223423@to.to> [S] Message-ID: <45223423@to.to>
[S] [S]
[S] This is just a test article. [S] This is just a test article.
[S] . [S] .
Example of an unsuccessful retrieval of an article by message- Example of an unsuccessful retrieval of an article by message-id
id
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] ARTICLE <i.am.not.there@nowhere.to> [C] ARTICLE <i.am.not.there@nowhere.to>
[S] 430 No Such Article Found [S] 430 No Such Article Found
Barber Page [15]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
Example of an unsuccessful retrieval of an article by number Example of an unsuccessful retrieval of an article by number
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 news.groups [S] 211 1234 3000234 3002322 news.groups
[C] ARTICLE 300256 [C] ARTICLE 300256
[S] 423 No such article number in this group [S] 423 No such article number in this group
Example of an unsuccessful retrieval of an article by number Example of an unsuccessful retrieval of an article by number because
because no newsgroup was selected first no newsgroup was selected first
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] ARTICLE 300256 [C] ARTICLE 300256
[S] 412 No newsgroup selected [S] 412 No newsgroup selected
Example of an attempt to retrieve an article when the current Example of an attempt to retrieve an article when the current group
group selected is empty selected is empty
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP example.empty.newsgroup [C] GROUP example.empty.newsgroup
[S] 211 0 0 0 example.empty.newsgroup [S] 211 0 0 0 example.empty.newsgroup
[C] ARTICLE [C] ARTICLE
[S] 420 No current article selected [S] 420 No current article selected
Example of a failure due to the service being unavailable Example of a failure due to the service being unavailable
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] ARTICLE <i.am.a.test.article@nowhere.to> [C] ARTICLE <i.am.a.test.article@nowhere.to>
Barber [Page 23]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
[S] 502 Service unavailable [S] 502 Service unavailable
9.2.2 HEAD 9.2.2 HEAD
HEAD <message-id> HEAD <message-id>
HEAD [number] HEAD [number]
The HEAD command behaves identically to the ARTICLE command The HEAD command behaves identically to the ARTICLE command except
except that, if the article exists, only the headers are that, if the article exists, only the headers are presented (the blank
presented (the blank line separating the headers and body MUST line separating the headers and body MUST NOT be included).
NOT be included).
9.2.2.1 Responses 9.2.2.1 Responses
First form (message-id specified): First form (message-id specified):
221 0 a article retrieved, headers follow (multiline) 221 0 a Article follows (multi-line response, a =
430 no such article message-id)
502 service unavailable 430 No article found with that message-id
502 Program error, function not performed
Second form (optional article number specified): Second form (optional article number specified):
221 n a article retrieved, headers follow (multiline) 221 n a Article follows (multi-line response, n =
412 no newsgroup selected article number, a = message-id)
420 no current article selected 412 No newsgroup selected
423 no such article number in this group 420 No current article selected
502 service unavailable 423 No such article in this newsgroup
502 Program error, function no performed
Except that only the headers are included in the response, the Except that only the headers are included in the response, the 221
221 response behaves identically to the 220 response of the response behaves identically to the 220 response of the ARTICLE
ARTICLE command. command.
9.2.2.2 Examples 9.2.2.2 Examples
Example of a successful retrieval of the headers in an article Example of a successful retrieval of the headers in an article (using
(using no article number) no article number)
Barber Page [16]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] HEAD [C] HEAD
[S] 220 3000234 <45223423@to.to> [S] 221 3000234 <45223423@to.to>
[S] Path: pathost!demo!somewhere!not-for-mail [S] Path: pathost!demo!somewhere!not-for-mail
[S] From: nobody@nowhere.to (Demo User) [S] From: nobody@nowhere.to (Demo User)
Barber [Page 24]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
[S] Newsgroups: misc.test [S] Newsgroups: misc.test
[S] Subject: I am just a test article [S] Subject: I am just a test article
[S] Date: 6 Oct 1998 04:38:40 -0500 [S] Date: 6 Oct 1998 04:38:40 -0500
[S] Organization: Nowhere, To [S] Organization: Nowhere, To
[S] Message-ID: <45223423@to.to> [S] Message-ID: <45223423@to.to>
[S] . [S] .
Example of a successful retrieval of the headers in an article Example of a successful retrieval of the headers in an article by
by message-id message-id
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] HEAD <45223423@to.to> [C] HEAD <45223423@to.to>
[S] 220 0 <45223423@to.to> [S] 221 0 <45223423@to.to>
[S] Path: pathost!demo!somewhere!not-for-mail [S] Path: pathost!demo!somewhere!not-for-mail
[S] From: nobody@nowhere.to (Demo User) [S] From: nobody@nowhere.to (Demo User)
[S] Newsgroups: misc.test [S] Newsgroups: misc.test
[S] Subject: I am just a test article [S] Subject: I am just a test article
[S] Date: 6 Oct 1998 04:38:40 -0500 [S] Date: 6 Oct 1998 04:38:40 -0500
[S] Organization: Nowhere, To [S] Organization: Nowhere, To
[S] Message-ID: <45223423@to.to> [S] Message-ID: <45223423@to.to>
[S] . [S] .
Example of an unsuccessful retrieval of the header of an Example of an unsuccessful retrieval of the header of an article by
article by message-id message-id
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] HEAD <i.am.not.there@nowhere.to> [C] HEAD <i.am.not.there@nowhere.to>
[S] 430 No Such Article Found [S] 430 No Such Article Found
Example of an unsuccessful retrieval of the header of an Example of an unsuccessful retrieval of the header of an article by
article by number number
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] HEAD 300256 [C] HEAD 300256
[S] 423 No such article number in this group [S] 423 No such article number in this group
Example of an unsuccessful retrieval the header of an article Example of an unsuccessful retrieval the header of an article by
by number because no newsgroup was selected first number because no newsgroup was selected first
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
Barber [Page 25]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
[C] HEAD 300256 [C] HEAD 300256
[S] 412 No newsgroup selected [S] 412 No newsgroup selected
Example of an attempt to retrieve the header of an article Example of an attempt to retrieve the header of an article when the
when the current group selected is empty current group selected is empty
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP example.empty.newsgroup [C] GROUP example.empty.newsgroup
Barber Page [17]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
[S] 211 0 0 0 example.empty.newsgroup [S] 211 0 0 0 example.empty.newsgroup
[C] HEAD [C] HEAD
[S] 420 No current article selected [S] 420 No current article selected
Example of a failure due to the service being unavailable Example of a failure due to the service being unavailable
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] HEAD <i.am.a.test.article@nowhere.to> [C] HEAD <i.am.a.test.article@nowhere.to>
[S] 502 Service unavailable [S] 502 Service unavailable
9.2.3 BODY 9.2.3 BODY
skipping to change at line 1288 skipping to change at line 1195
[S] 420 No current article selected [S] 420 No current article selected
Example of a failure due to the service being unavailable Example of a failure due to the service being unavailable
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] HEAD <i.am.a.test.article@nowhere.to> [C] HEAD <i.am.a.test.article@nowhere.to>
[S] 502 Service unavailable [S] 502 Service unavailable
9.2.3 BODY 9.2.3 BODY
BODY <message-id> BODY <message-id>
BODY [number] BODY [number]
The BODY command behaves identically to the ARTICLE command The BODY command behaves identically to the ARTICLE command except
except that, if the article exists, only the body is presented that, if the article exists, only the body is presented (the blank
(the blank line separating the headers and body MUST NOT be line separating the headers and body MUST NOT be included).
included).
9.2.3.1 Responses 9.2.3.1 Responses
First form (message-id specified): First form (message-id specified):
222 0 a article retrieved, body follows (multiline) 222 0 a Article follows (multi-line response, a =
430 no such article message-id)
502 service unavailable 430 No article found with that message-id
502 Program error, function not performed
Second form (optional article number specified): Second form (optional article number specified):
222 n a article retrieved, body follows (multiline) 222 n a Article follows (multi-line response, n =
412 no newsgroup selected article number, a = message-id)
420 no current article selected 412 No newsgroup selected
423 no such article number in this group 420 No current article selected
502 service unavailable 423 No such article in this newsgroup
502 Program error, function no performed
Barber [Page 26]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
Except that only the body is included in the response, the 222 Except that only the body is included in the response, the 222
response behaves identically to the 220 response of the response behaves identically to the 220 response of the ARTICLE
ARTICLE command. command.
9.2.3.2 Examples 9.2.3.2 Examples
Example of a successful retrieval of the body of an article Example of a successful retrieval of the body of an article (using no
(using no article number) article number)
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] BODY [C] BODY
[S] 222 3000234 <45223423@to.to> [S] 222 3000234 <45223423@to.to>
[S] This is just a test article. [S] This is just a test article.
[S] . [S] .
Example of a successful retrieval of the body of an article by Example of a successful retrieval of the body of an article by
message-id message-id
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] BODY <45223423@to.to> [C] BODY <45223423@to.to>
[S] 222 0 <45223423@to.to> [S] 222 0 <45223423@to.to>
[S] This is just a test article. [S] This is just a test article.
[S] . [S] .
Example of an unsuccessful retrieval of the body of an article Example of an unsuccessful retrieval of the body of an article by
by message-id
Barber Page [18]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
message-id
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] BODY <i.am.not.there@nowhere.to> [C] BODY <i.am.not.there@nowhere.to>
[S] 430 No Such Article Found [S] 430 No Such Article Found
Example of an unsuccessful retrieval of the body of an article Example of an unsuccessful retrieval of the body of an article by
by number number
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] BODY 300256 [C] BODY 300256
[S] 423 No such article number in this group [S] 423 No such article number in this group
Example of an unsuccessful retrieval of the body of an article Example of an unsuccessful retrieval of the body of an article by
by number because no newsgroup was selected first number because no newsgroup was selected first
Barber [Page 27]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] BODY 300256 [C] BODY 300256
[S] 412 No newsgroup selected [S] 412 No newsgroup selected
Example of an attempt to retrieve the body of an article when Example of an attempt to retrieve the body of an article when the
the current group selected is empty current group selected is empty
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP example.empty.newsgroup [C] GROUP example.empty.newsgroup
[S] 211 0 0 0 example.empty.newsgroup [S] 211 0 0 0 example.empty.newsgroup
[C] BODY [C] BODY
[S] 420 No current article selected [S] 420 No current article selected
Example of a failure due to the service being unavailable Example of a failure due to the service being unavailable
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] BODY <i.am.a.test.article@nowhere.to> [C] BODY <i.am.a.test.article@nowhere.to>
[S] 502 Service unavailable [S] 502 Service unavailable
skipping to change at line 1381 skipping to change at line 1284
[S] 211 0 0 0 example.empty.newsgroup [S] 211 0 0 0 example.empty.newsgroup
[C] BODY [C] BODY
[S] 420 No current article selected [S] 420 No current article selected
Example of a failure due to the service being unavailable Example of a failure due to the service being unavailable
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] BODY <i.am.a.test.article@nowhere.to> [C] BODY <i.am.a.test.article@nowhere.to>
[S] 502 Service unavailable [S] 502 Service unavailable
9.2.4 STAT 9.2.4 STAT
STAT <message-id> STAT <message-id>
STAT [number] STAT [number]
The STAT command behaves identically to the ARTICLE command The STAT command behaves identically to the ARTICLE command except
except that, if the article exists, it is NOT presented to the that, if the article exists, it is NOT presented to the client.
client. This command allows the client to determine whether an article exists,
This command allows the client to determine whether an article and in the second form what its message-id is, without having to
exists, and in the second form what its message-id is, without process an arbitrary amount of text.
having to process an arbitrary amount of text.
9.2.4.1 Responses 9.2.4.1 Responses
First form (message-id specified): First form (message-id specified):
223 0 a article exists 223 0 a Article follows (a = message-id)
430 no such article 430 No article found with that message-id
502 service unavailable 502 Program error, function not performed
Second form (optional article number specified): Second form (optional article number specified):
223 n a article exists 223 n a Article follows (n = article number, a =
412 no newsgroup selected message-id)
420 no current article selected 412 No newsgroup selected
423 no such article number in this group 420 No current article selected
502 service unavailable 423 No such article in this newsgroup
502 Program error, function no performed
Barber [Page 28] The parameters of the 223 response are identical to those that would
Barber Page [19]
INTERNET DRAFT S. Barber INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services Expires: May 15, 2002 Academ Consulting Services
March 2001 November 2001
The parameters of the 223 response are identical to those that have been given in a 220 response to the equivalent ARTICLE command.
would have been given in a 220 response to the equivalent However, the response is NOT multi-line.
ARTICLE command. However, the response is NOT multiline.
9.2.4.2 Examples 9.2.4.2 Examples
Example of STAT on an existing article (using no article Example of STAT on an existing article (using no article number)
number)
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] STAT [C] STAT
[S] 223 3000234 <45223423@to.to> [S] 223 3000234 <45223423@to.to>
Example of a STAT of an existing article by message-id Example of a STAT of an existing article by message-id
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] STAT <45223423@to.to> [C] STAT <45223423@to.to>
[S] 223 0 <45223423@to.to> [S] 223 0 <45223423@to.to>
Example of an STAT of an article not on the server by message- Example of an STAT of an article not on the server by message-id
id
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] STAT <i.am.not.there@nowhere.to> [C] STAT <i.am.not.there@nowhere.to>
[S] 430 No Such Article Found [S] 430 No Such Article Found
Example of STAT of an article not in the server by number Example of STAT of an article not in the server by number
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] STAT 300256 [C] STAT 300256
[S] 423 No such article number in this group [S] 423 No such article number in this group
Example of STAT of an article by number when no newsgroup was Example of STAT of an article by number when no newsgroup was selected
selected first first
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] STAT 300256 [C] STAT 300256
[S] 412 No newsgroup selected [S] 412 No newsgroup selected
Barber [Page 29] Example of STAT of an article when the current group selected is empty
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
Example of STAT of an article when the current group selected
is empty
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP example.empty.newsgroup [C] GROUP example.empty.newsgroup
[S] 211 0 0 0 example.empty.newsgroup [S] 211 0 0 0 example.empty.newsgroup
[C] STAT [C] STAT
[S] 420 No current article selected [S] 420 No current article selected
Example of a failure due to the service being unavailable Example of a failure due to the service being unavailable
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] STAT <i.am.a.test.article@nowhere.to> [C] STAT <i.am.a.test.article@nowhere.to>
[S] 502 Service unavailable [S] 502 Service unavailable
9.3 Article Posting 9.3 Article Posting
Article posting is done in one of two modes: individual Article posting is done in one of two modes: individual article
article posting from news reading clients and article transfer posting from news reading clients and article transfer from other news
from other news servers. servers.
9.3.1 POST 9.3.1 POST
Barber Page [20]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
POST POST
If posting is allowed, response code 340 MUST be returned to If posting is allowed, response code 340 MUST be returned to indicate
indicate that the article to be posted should be sent. that the article to be posted should be sent. Response code 440 MUST
Response code 440 MUST be sent if that posting is prohibited be sent if that posting is prohibited for some installation-dependent
for some installation-dependent reason. reason.
If posting is permitted, the article MUST be presented to the If posting is permitted, the article MUST be presented to the server
server by the client in the format specified by RFC 1036. The by the client in the format specified by RFC 1036 (or by any of its
text forming the header and body of the message to be posted successors or extensions). The text forming the header and body of the
MUST be sent by the client using the conventions for text message to be posted MUST be sent by the client in the format defined
received from the news server: A single period (".") on a line above (section 4) for multi-line responses (except that there is no
indicates the end of the text, with lines starting with a initial line containing a response code). Thus a single period (".")
period in the original text having that period doubled during on a line indicates the end of the text, and lines starting with a
period in the original text have that period doubled during
transmission. transmission.
Following the presentation of the termination sequence by the Following the presentation of the termination sequence by the client,
client, the server MUST return a response code indicating the server MUST return a response code indicating success or failure
success or failure of the article transfer. Note that response of the article transfer. Note that response codes 340 and 440 are used
codes 340 and 440 are used in direct response to the POST in direct response to the POST command. Others are returned following
command. Others are returned following the sending of the the sending of the article.
article.
Barber [Page 30] No attempt shall be made by the server to filter characters, fold or
limit lines, or otherwise process incoming text. The intent is that
the server just passes the incoming message to be posted to the server
installation's news posting software, which is not part of this
specification.
INTERNET DRAFT S. Barber The client SHOULD NOT assume that the article has been successfully
Expires: October 30, 2001 Academ Consulting Services transferred unless it receives an affirmative response from the
March 2001 server. Since, however, the affirmative response may have been sent
No attempt shall be made by the server to filter characters, and lost, the client SHOULD use the same message-id in the article
fold or limit lines, or otherwise process incoming text. The when resending it or check whether the article was successfully posted
intent is that the server just passes the incoming message to before resending it to ensure that the resend will not result in a
be posted to the server installation's news posting software, duplicate article.
which is not part of this specification.
9.3.1.1 Responses 9.3.1.1 Responses
240 article received ok 240 Article received ok
340 send article to be posted. End with <CR-LF>.<CR-LF> 340 Send article to be posted
440 posting not allowed 440 Posting not permitted
441 posting failed 441 Posting failed
9.3.1.2 Examples 9.3.1.2 Examples
Example of a successful posting Example of a successful posting
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] POST [C] POST
[S] 340 Input article. End with <CR-LF>.<CR-LF> [S] 340 Input article. End with <CR-LF>.<CR-LF>
[C] From: demo@testdomain.com(Demo User) [C] From: demo@testdomain.com(Demo User)
[C] Newsgroups: misc.test [C] Newsgroups: misc.test
[C] Subject: I am just a test article [C] Subject: I am just a test article
skipping to change at line 1539 skipping to change at line 1442
[C] [C]
[C] This is just a test article. [C] This is just a test article.
[C] . [C] .
[S] 240 Article received ok [S] 240 Article received ok
Example of an unsuccessful posting Example of an unsuccessful posting
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] POST [C] POST
[S] 340 Input article. End with <CR-LF>.<CR-LF> [S] 340 Input article. End with <CR-LF>.<CR-LF>
[C] From: demo@testdomain.com(Demo User) [C] From: demo@testdomain.com(Demo User)
Barber Page [21]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
[C] Newsgroups: misc.test [C] Newsgroups: misc.test
[C] Subject: I am just a test article [C] Subject: I am just a test article
[C] Organization: Testdomain, USA [C] Organization: Testdomain, USA
[C] [C]
Barber [Page 31]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
[C] This is just a test article. [C] This is just a test article.
[C] . [C] .
[S] 441 Posting failed [S] 441 Posting failed
Example of an attempt to posting when posting is not allowed Example of an attempt to posting when posting is not allowed
[S] 201 NNTP Service Ready, read-only [S] 201 NNTP Service Ready, read-only
[C] POST [C] POST
[S] 440 Posting not permitted [S] 440 Posting not permitted
9.3.2 IHAVE 9.3.2 IHAVE
IHAVE <message-id> IHAVE <message-id>
The IHAVE command informs the server that the client has an The IHAVE command informs the server that the client has an article
article whose id is <message-id>. If the server desires a copy whose id is <message-id>. If the server desires a copy of that
of that article, it MUST return a response instructing the article, it MUST return response code 335 instructing the client to
client to send the entire article. If the server does not want send the entire article. If the server does not want the article (if,
the article (if, for example, the server already has a copy of for example, the server already has a copy of it), response code 435
it), a response indicating that the article is not wanted MUST indicating that the article is not wanted MUST be returned. Finally,
be returned. if the article isn't wanted immediately but the client should retry
later if possible (if, for example, another client is in the process
of sending the same article to the server), response code 436 MUST be
returned.
If transmission of the article is requested, the client MUST If transmission of the article is requested, the client MUST send the
send the entire article, including header and body, in the entire article, including header and body, in the format defined above
manner specified for text transmission from the server. The (section 4) for multi-line responses (except that there is no initial
server MUST return a response code indicating success or line containing a response code). Thus a single period (".") on a line
failure of the transferal of the article. indicates the end of the text, and lines starting with a period in the
original text have that period doubled during transmission. The server
MUST then return a response code indicating success or failure of the
transferal of the article.
This function differs from the POST command in that it is This function differs from the POST command in that it is intended for
intended for use in transferring already-posted articles use in transferring already-posted articles between hosts. It SHOULD
between hosts. It SHOULD NOT be used when the client is a NOT be used when the client is a personal news reading program, since
personal news reading program. In particular, this function this command indicates that the forthcoming article has already been
will invoke the server's news posting program with the posted at another site and is being forwarded from another host.
appropriate settings (flags, options, etc.) to indicate that However, the server MAY elect not to post or forward the article if
the forthcoming article is being forwarded from another host. after further examination of the article it deems it inappropriate to
However, the server MAY elect not to post or forward the do so. Reasons for such subsequent rejection of an article may include
article if after further examination of the article it deems such problems as inappropriate newsgroups or distributions, disk space
it inappropriate to do so. Reasons for such subsequent limitations, article lengths, garbled headers, and the like. These are
rejection of an article may include such problems as typically restrictions enforced by the server host's news software and
inappropriate newsgroups or distributions, disk space not necessarily the NNTP server itself.
limitations, article lengths, garbled headers, and the like.
These are typically restrictions enforced by the server host's The client SHOULD NOT assume that the article has been successfully
news software and not necessarily the NNTP server itself. transferred unless it receives an affirmative response from the
server. A lack of response (such as a dropped network connection or a
network timeout) SHOULD be treated the same as a 436 error response.
Because some news server software may not be able to immediately
determine whether or not an article is suitable for posting or
forwarding, an NNTP server MAY acknowledge the successful transfer of
the article (with a 235 response) but later silently discard it.
9.3.2.1 Responses 9.3.2.1 Responses
Barber [Page 32] 235 Article transferred ok
335 Send article to be transferred
435 Article not wanted, please don't send it.
Barber Page [22]
INTERNET DRAFT S. Barber INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services Expires: May 15, 2002 Academ Consulting Services
March 2001 November 2001
235 article transferred ok
335 send article to be transferred. End with <CR-
LF>.<CR-LF>
435 article not wanted - do not send it
436 transfer failed - try again later
437 article rejected - do not try again
Because some host news posting software may not be able to 436 Transfer failed, try again later.
immediately render status on the whether an article is 437 Article rejected, please don't sent it again.
inappropriate for posting or forwarding, an NNTP server MAY
acknowledge the successful transfer of the article and later
silently discard it. Thus, an NNTP server MAY return the 235
acknowledgment code and later discard the received article.
9.3.2.2 Examples 9.3.2.2 Examples
Example of successfully sending an article to another site Example of successfully sending an article to another site
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] IHAVE <i.am.an.article.you.will.want@nowhere.to> [C] IHAVE <i.am.an.article.you.will.want@nowhere.to>
[S] 335 Send it. End with <CR-LF>.<CR-LF> [S] 335 Send it. End with <CR-LF>.<CR-LF>
[C] Path: pathost!demo!somewhere!not-for-mail [C] Path: pathost!demo!somewhere!not-for-mail
[C] From: nobody@nowhere.to (Demo User) [C] From: nobody@nowhere.to (Demo User)
[C] Newsgroups: misc.test [C] Newsgroups: misc.test
skipping to change at line 1636 skipping to change at line 1546
[C] [C]
[C] This is just a test article. [C] This is just a test article.
[C] . [C] .
[S] 235 Article transferred ok [S] 235 Article transferred ok
Example of sending an article to another site that rejects it Example of sending an article to another site that rejects it
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] IHAVE <i.am.an.article.you.will.want@nowhere.to> [C] IHAVE <i.am.an.article.you.will.want@nowhere.to>
[S] 335 Send it. End with <CR-LF>.<CR-LF> [S] 335 Send it. End with <CR-LF>.<CR-LF>
[C] Path: pathost!demo!somewhere!not-for-mail [C] Path: pathost!demo!somewhere!not-for-mail
Barber [Page 33]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
[C] From: nobody@nowhere.to (Demo User) [C] From: nobody@nowhere.to (Demo User)
[C] Newsgroups: misc.test [C] Newsgroups: misc.test
[C] Subject: I am just a test article [C] Subject: I am just a test article
[C] Date: 6 Oct 1998 04:38:40 -0500 [C] Date: 6 Oct 1998 04:38:40 -0500
[C] Organization: Nowhere, To [C] Organization: Nowhere, To
[C] Message-ID: <i.am.a.test.article@nowhere.to> [C] Message-ID: <i.am.a.test.article@nowhere.to>
[C] [C]
[C] This is just a test article. [C] This is just a test article.
[C] . [C] .
[S] 437 Article rejected. Don't send again [S] 437 Article rejected. Don't send again
Example of sending an article to another site where the Example of sending an article to another site where the transfer fails
transfer fails
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] IHAVE <i.am.an.article.you.will.want@nowhere.to> [C] IHAVE <i.am.an.article.you.will.want@nowhere.to>
[S] 335 Send it. End with <CR-LF>.<CR-LF> [S] 335 Send it. End with <CR-LF>.<CR-LF>
[C] Path: pathost!demo!somewhere!not-for-mail [C] Path: pathost!demo!somewhere!not-for-mail
[C] From: nobody@nowhere.to (Demo User) [C] From: nobody@nowhere.to (Demo User)
[C] Newsgroups: misc.test [C] Newsgroups: misc.test
[C] Subject: I am just a test article [C] Subject: I am just a test article
[C] Date: 6 Oct 1998 04:38:40 -0500 [C] Date: 6 Oct 1998 04:38:40 -0500
Barber Page [23]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
[C] Organization: Nowhere, To [C] Organization: Nowhere, To
[C] Message-ID: <i.am.a.test.article@nowhere.to> [C] Message-ID: <i.am.a.test.article@nowhere.to>
[C] [C]
[C] This is just a test article. [C] This is just a test article.
[C] . [C] .
[S] 436 Transfer failed [S] 436 Transfer failed
Example of sending an article to another site that rejects it Example of sending an article to a site that already has it
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] IHAVE <i.am.an.article.you.will.want@nowhere.to> [C] IHAVE <i.am.an.article.you.have@nowhere.to>
[S] 335 Send it. End with <CR-LF>.<CR-LF> [S] 435 Duplicate
[C] Path: pathost!demo!somewhere!not-for-mail
Barber [Page 34]
INTERNET DRAFT S. Barber Example of sending an article to a site that requests the article be
Expires: October 30, 2001 Academ Consulting Services tried again later
March 2001 [S] 200 NNTP Service Ready
[C] From: nobody@nowhere.to (Demo User) [C] IHAVE <i.am.an.article.you.defer@nowhere.to>
[C] Newsgroups: misc.test [S] 436 Retry later
[C] Subject: I am just a test article
[C] Date: 6 Oct 1998 04:38:40 -0500
[C] Organization: Nowhere, To
[C] Message-ID: <i.am.a.test.article@nowhere.to>
[C]
[C] This is just a test article.
[C] .
[S] 435 Don't send it again
9.4 The LIST Keyword 9.4 The LIST Keyword
9.4.1 LIST 9.4.1 LIST
LIST [ACTIVE [wildmat]] LIST [ACTIVE [wildmat]]
The response to the LIST keyword with no parameters returns a The response to the LIST keyword with no parameters returns a list of
list of valid newsgroups and associated information. Each valid newsgroups and associated information. Each newsgroup is sent
newsgroup is sent as a line of text in the following format: as a line of text in the following format:
group first last status group first last status
where <group> is the name of the newsgroup, <last> is the
number of the last known article currently in that newsgroup,
<first> is the number of the first article currently in the
newsgroup, and <status> indicates the current status of the
group on this server. Typically, the <status> will be consist
of the US-ASCII character 'y' where posting is permitted, 'n'
where posting is not permitted and 'm' where postings will be
forwarded to the newsgroup moderator by the news server. Other
status strings may exist. The definition of these other values
and the circumstances under which they are returned is covered
in other specifications.
The <first> and <last> fields will always be numeric. They where <group> is the name of the newsgroup, <last> is the number of
may have leading zeros. The <first> field corresponds to the the last known article currently in that newsgroup, <first> is the
"reported low water mark" and the <last> field corresponds to number of the first article currently in the newsgroup, and <status>
the "reported high water mark" described in the GROUP command indicates the current status of the group on this server. Typically,
(see Section 9.1.1.1). the <status> will be consist of the US-ASCII character 'y' where
posting is permitted, 'n' where posting is not permitted and 'm' where
postings will be forwarded to the newsgroup moderator by the news
server. Other status strings may exist. The definition of these other
values and the circumstances under which they are returned is covered
in other specifications. Each field in the line is separated from its
neighboring fields by one or more US-ASCII spaces.
The status of a newsgroup only indicates how posts to that The <first> and <last> fields will always be numeric. They may have
newsgroup are processed. It does not indicate if the current leading zeros. The <first> field corresponds to the "reported low
client is permitted to post. That is indicated by the status water mark" and the <last> field corresponds to the "reported high
code returned as part of the greeting. water mark" described in the GROUP command (see Section 9.1.1.1).
Barber [Page 35] The status of a newsgroup only indicates how posts to that newsgroup
are processed. It does not indicate if the current client is permitted
to post. That is indicated by the status code returned as part of the
greeting.
INTERNET DRAFT S. Barber Please note that an empty list (i.e., the text body returned by this
Expires: October 30, 2001 Academ Consulting Services command consists only of the terminating period) is a possible valid
March 2001 response, and indicates that there are currently no valid newsgroups.
Please note that an empty list (i.e., the text body returned
by this command consists only of the terminating period) is a
possible valid response, and indicates that there are
currently no valid newsgroups.
If the optional wildmat parameter is specified, the list is If the optional wildmat parameter is specified, the list is limited to
limited to only the groups that match the pattern. only the groups that match the pattern.
Specifying a single group is usually very efficient for the Specifying a single group is usually very efficient for the server.
server. Multiple groups may be specified by using wildmat Multiple groups may be specified by using wildmat patterns (described
patterns (described in section 5). in section 5).
9.4.1.1 Responses 9.4.1.1 Responses
215 list of newsgroups follows 215 Information Follows (multi-line response)
Barber Page [24]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
9.4.1.2 Examples 9.4.1.2 Examples
Example of LIST returning a list of newsgroups Example of LIST returning a list of newsgroups
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LIST [C] LIST
[S] 215 list of newsgroups follows [S] 215 list of newsgroups follows
[S] misc.test 3000234 3002322 y [S] misc.test 3000234 3002322 y
[S] alt.fc-writers.recovery 1 4 y [S] alt.fc-writers.recovery 1 4 y
[S] tx.natives.recovery 56 89 y [S] tx.natives.recovery 56 89 y
[S] . [S] .
Example of LIST returning no newsgroups Example of LIST returning no newsgroups
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LIST [C] LIST
[S] 215 list of newsgroups follows [S] 215 list of newsgroups follows
[S] . [S] .
9.4.2 LIST ACTIVE.TIMES 9.4.2 LIST ACTIVE.TIMES
LIST ACTIVE.TIMES [wildmat] LIST ACTIVE.TIMES [wildmat]
The active.times file is maintained by some news transport systems to
contain information about who created a particular newsgroup and when.
The active.times file is maintained by some news transport The format of this file includes three fields separated from each
systems to contain information about who created a particular other by one or more US-ASCII space characters. The first field is the
newsgroup and when. The format of this file includes three name of the newsgroup. The second is the time when this group was
fields. The first field is the name of the newsgroup. The created on this news server measured in seconds since the start of
second is the time when this group was created on this news January 1, 1970. The third is the email address of the entity that
server measured in seconds since the start of January 1, 1970. created the newsgroup and must be a mailbox as defined in RFC 2822.
The third is the email address of the entity that created the
newsgroup. When executed, the information is displayed
Barber [Page 36]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
following the 215 response. When display is completed, the
server will send a period on a line by itself. If the
information is not available, the server will return the 503
error response. If the server does not recognize the command,
it SHOULD return the 501 error response.
If the optional wildmat parameter is specified, the list is When executed, the information is displayed following the 215
limited to only the groups that match the pattern. response. When display is completed, the server will send a period on
a line by itself. If the information is not available, the server will
return the 503 error response. If the server does not recognize the
command, it SHOULD return the 501 error response.
Specifying a single group is usually very efficient for the If the optional wildmat parameter is specified, the list is limited to
server. Multiple groups may be specified by using wildmat only the groups that match the pattern.
patterns (described in section 5). Multiple groups may be specified by using wildmat patterns(described
in section 5).
9.4.2.1 Responses 9.4.2.1 Responses
215 information follows 215 Information Follows (multi-line response)
501 Syntax error 501 Syntax error
503 program error, function not performed 503 Program error, function not performed
9.4.2.2 Examples 9.4.2.2 Examples
Example of LIST ACTIVE.TIMES returning a list of newsgroups Example of LIST ACTIVE.TIMES returning a list of newsgroups
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LIST ACTIVE.TIMES [C] LIST ACTIVE.TIMES
[S] 215 information follows [S] 215 information follows
[S] misc.test 930445408 <creatme@isc.org> [S] misc.test 930445408 <creatme@isc.org>
[S] alt.rfc-writers.recovery 930562309 <m@nowhere.to> [S] alt.rfc-writers.recovery 930562309 <m@nowhere.to>
[S] tx.natives.recovery 930678923 <sob@academ.com> [S] tx.natives.recovery 930678923 <sob@academ.com>
[S] . [S] .
Example of LIST ACTIVE.TIMES returning an error (The server Barber Page [25]
software is not configured to maintain this information, but
does recognize the command as valid.) INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
Example of LIST ACTIVE.TIMES returning an error (The server software is
not configured to maintain this information, but does recognize the
command as valid.)
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LIST ACTIVE.TIMES [C] LIST ACTIVE.TIMES
[S] 503 program error, function not performed [S] 503 program error, function not performed
Example of LIST ACTIVE.TIMES sent to a server that does not Example of LIST ACTIVE.TIMES sent to a server that does not recognize
recognize this argument (e.g. The software does not maintain this argument (e.g. The software does not maintain this information.)
this information.)
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
Barber [Page 37]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
[C] LIST ACTIVE.TIMES [C] LIST ACTIVE.TIMES
[S] 501 Syntax Error [S] 501 Syntax Error
9.4.3 LIST DISTRIBUTIONS 9.4.3 LIST DISTRIBUTIONS
LIST DISTRIBUTIONS LIST DISTRIBUTIONS
The distributions file is maintained by some news transport systems to
The distributions file is maintained by some news transport contain information about valid values for the Distribution: line in a
systems to contain information about valid values for the news article header and about what the values mean. Each line contains
Distribution: line in a news article header and about what the two fields, the value and a short explanation on the meaning of the
values mean. Each line contains two fields, the value and a value. The first field is separated from the second field by one or
short explanation on the meaning of the value. When executed, more US-ASCII spaces. When executed, the information is displayed
the information is displayed following the 215 response. When following the 215 response. When display is completed, the server will
display is completed, the server will send a period on a line send a period on a line by itself. If the information is not
by itself. If the information is not available, the server available, the server will return the 503 error response. If the
will return the 503 error response. If the server does not server does not recognize this command, it SHOULD return the 501 error
recognize this command, it SHOULD return the 501 error
response. response.
9.4.3.1 Responses 9.4.3.1 Responses
215 information follows 215 Information Follows (multi-line response)
501 Syntax error 501 Syntax error
503 program error, function not performed 503 Program error, function not performed
9.4.3.2 Examples 9.4.3.2 Examples
Example of LIST DISTRIBUTIONS returning a list of newsgroups Example of LIST DISTRIBUTIONS returning a list of newsgroups
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LIST DISTRIBUTIONS [C] LIST DISTRIBUTIONS
[S] 215 information follows [S] 215 information follows
[S] usa United States of America [S] usa United States of America
[S] na North America [S] na North America
[S] world All over the World [S] world All over the World
[S] . [S] .
Example of LIST DISTRIBUTIONS returning an error (e.g. The Example of LIST DISTRIBUTIONS returning an error (e.g. The server
server software is not configured to maintain this software is not configured to maintain this information, but does
information, but does recognize the command as valid.) recognize the command as valid.)
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LIST DISTRIBUTIONS [C] LIST DISTRIBUTIONS
[S] 503 program error, function not performed [S] 503 program error, function not performed
Barber [Page 38] Example of LIST DISTRIBUTIONS sent to a server that does not recognize
the command (e.g. The server does not maintain this information
INTERNET DRAFT S. Barber regardless of configuration.)
Expires: October 30, 2001 Academ Consulting Services
March 2001
Example of LIST DISTRIBUTIONS sent to a server that does not
recognize the command (e.g. The server does not maintain this
information regardless of configuration.)
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LIST DISTRIBUTIONS [C] LIST DISTRIBUTIONS
Barber Page [26]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
[S] 501 Syntax Error [S] 501 Syntax Error
9.4.4 LIST DISTRIB.PATS 9.4.4 LIST DISTRIB.PATS
LIST DISTRIB.PATS LIST DISTRIB.PATS
The distrib.pats file is maintained by some news transport systems to
The distrib.pats file is maintained by some news transport allow clients to choose a value for the Distribution: line in the
systems to allow clients to choose a value for the header of a news article being posted. The information returned
Distribution: line in the header of a news article being consists of lines, in no particular order, each of which contains
posted. The information returned consists of lines, in no three fields separated by colons. These fields are a weight, a group
particular order, each of which contains three fields name or wildmat pattern, and a Distribution: value, in that order.
separated by colons. These fields are a weight, a group name The client MAY use this information to select a Distribution: value
or wildmat pattern, and a Distribution: value, in that order. based on the name of a newsgroup. To do so, it should determine the
lines whose second field matches the newsgroup name, select that line
The client MAY use this information to select a Distribution: with the highest weight (with 0 being the lowest), and use the
value based on the name of a newsgroup. To do so, it should Distribution: field from that line.
determine the lines whose second field matches the newsgroup
name, select that line with the highest weight (with 0 being
the lowest), and use the Distribution: field from that line.
When executed, the information is displayed following the 215 When executed, the information is displayed following the 215
response. When display is completed, the server will send a response. When display is completed, the server will send a period on
period on a line by itself. If the information is not a line by itself. If the information is not available, the server will
available, the server will return the 503 error response. If return the 503 error response. If this command is not recognized, the
this command is not recognized, the server SHOULD return the server SHOULD return the 501 error response.
501 error response.
9.4.4.1 Responses 9.4.4.1 Responses
215 information follows 215 Information Follows (multi-line response)
501 Syntax error 501 Syntax error
503 program error, function not performed 503 Program error, function not performed
9.4.4.2 Examples 9.4.4.2 Examples
Example of LIST DISTRIB.PATS returning a list of newsgroups Example of LIST DISTRIB.PATS returning a list of newsgroups
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LIST DISTRIB.PATS [C] LIST DISTRIB.PATS
[S] 215 information follows [S] 215 information follows
[S] 10:local.*:local [S] 10:local.*:local
Barber [Page 39]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
[S] . [S] .
Example of LIST DISTRIB.PATS returning an error (e.g. The Example of LIST DISTRIB.PATS returning an error (e.g. The server software
server software is not configured to maintain this is not configured to maintain this information, but does recognize the
information, but does recognize the command as valid.) command as valid.)
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LIST DISTRIB.PATS [C] LIST DISTRIB.PATS
[S] 503 program error, function not performed [S] 503 program error, function not performed
Example of LIST DISTRIB.PATS sent to a server that does not Example of LIST DISTRIB.PATS sent to a server that does not recognize the
recognize the command (e.g. The software does not maintain command (e.g. The software does not maintain this information regardless
this information regardless of configuration.) of configuration.)
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LIST DISTRIB.PATS [C] LIST DISTRIB.PATS
[S] 501 Syntax Error [S] 501 Syntax Error
9.4.5 LIST NEWSGROUPS 9.4.5 LIST NEWSGROUPS
LIST NEWSGROUPS [wildmat] LIST NEWSGROUPS [wildmat]
The newsgroups file is maintained by some news transport systems to
contain the name of each newsgroup that is active on the server and
a short description about the purpose of each newsgroup. Each line
in the file contains two fields, the newsgroup name and a short
explanation of the purpose of that newsgroup. The first field is
separated from the second field by one or more US-ASCII spaces. When
The newsgroups file is maintained by some news transport Barber Page [27]
systems to contain the name of each newsgroup that is
active on the server and a short description about the INTERNET DRAFT S. Barber
purpose of each newsgroup. Each line in the file contains Expires: May 15, 2002 Academ Consulting Services
two fields, the newsgroup name and a short explanation of November 2001
the purpose of that newsgroup. When executed, the executed, the information is displayed following the 215 response.
information is displayed following the 215 response. When When display is completed, the server will send a period on a line
display is completed, the server will send a period on a by itself. If the information is not available, the server will
line by itself. If the information is not available, the return the 503 response. If the server does not recognize the
server will return the 503 response. If the server does not command it should return a 501 response. If the optional matching
recognize the command it should return a 501 response. If parameter is specified, the list is limited to only the groups that
the optional matching parameter is specified, the list is match the pattern (no matching is done on the group descriptions).
limited to only the groups that match the pattern (no Multiple groups may be specified by using a wildmat(see section 5),
matching is done on the group descriptions). Specifying a not regular expressions. If nothing is matched an empty list is
single group is usually very efficient for the server, and returned, not an error.
multiple groups may be specified by using a wildmat(see
section 5), not regular expressions. If nothing is matched
an empty list is returned, not an error.
9.4.5.1 Responses 9.4.5.1 Responses
215 information follows 215 Information Follows (multi-line response)
501 Syntax error 501 Syntax error
503 program error, function not performed 503 Program error, function not performed
Barber [Page 40]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
9.4.5.2 Examples 9.4.5.2 Examples
Example of LIST NEWSGROUPS returning a list of newsgroups Example of LIST NEWSGROUPS returning a list of newsgroups
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LIST NEWSGROUPS [C] LIST NEWSGROUPS
[S] 215 information follows [S] 215 information follows
[S] misc.test General Usenet testing [S] misc.test General Usenet testing
[S] alt.rfc-writers.recovery RFC Writers Recovery [S] alt.rfc-writers.recovery RFC Writers Recovery
[S] tx.natives.recovery Texas Natives Recovery [S] tx.natives.recovery Texas Natives Recovery
[S] . [S] .
Example of LIST NEWSGROUPS returning an error (e.g. The server Example of LIST NEWSGROUPS returning an error (e.g. The server
software recognizes the command as valid, but the information software recognizes the command as valid, but the information is not
is not available.) available.)
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LIST NEWSGROUPS [C] LIST NEWSGROUPS
[S] 503 program error, function not performed [S] 503 program error, function not performed
9.5 Standard extensions 9.5 Standard extensions
Each of the following sections describes an extension that a Each of the following sections describes an extension that a server
server MAY provide. If the server provides the extension, it MAY provide. If the server provides the extension, it MUST include the
MUST include the appropriate extension label in the response appropriate extension label in the response to LIST EXTENSIONS. If it
to LIST EXTENSIONS. If it does not provide it, it MUST NOT does not provide it, it MUST NOT include the appropriate extension
include the appropriate extension label. The descriptions of label. The descriptions of facilities in each section are written as
facilities in each section are written as if the extension is if the extension is provided. If it is not provided, the entire
provided. If it is not provided, the entire section should be section should be ignored.
ignored.
9.5.1 LISTGROUP extension 9.5.1 LISTGROUP extension
This extension provides one command and has the extension This extension provides one command and has the extension label
label LISTGROUP. LISTGROUP.
9.5.1.1 The LISTGROUP Command 9.5.1.1 The LISTGROUP Command
LISTGROUP [ggg] LISTGROUP [ggg]
The LISTGROUP command is used to get a listing of all the article
numbers in a particular newsgroup.
The optional parameter ggg is the name of the newsgroup to be
selected (e.g. "news.software.b"). A list of valid newsgroups may
be obtained from the LIST command. If no group is specified, the
current group is used as the default argument.
The LISTGROUP command is used to get a listing of all the Barber Page [28]
article numbers in a particular newsgroup.
Barber [Page 41]
INTERNET DRAFT S. Barber INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services Expires: May 15, 2002 Academ Consulting Services
March 2001 November 2001
The optional parameter ggg is the name of the newsgroup to
be selected (e.g. "news.software.b"). A list of valid
newsgroups may be obtained from the LIST command. If no
group is specified, the current group is used as the
default argument.
The successful selection response will be a list of the The successful selection response will be a list of the article
article numbers in the group followed by a period on a line numbers in the group followed by a period on a line by itself. The
by itself. The list starts on the next line following the list starts on the next line following the 211 response code.
211 response code.
When a valid group is selected by means of this command, When a valid group is selected by means of this command, the
the internally maintained "current article pointer" MUST be internally maintained "current article pointer" MUST be set to the
set to the first article in the group and the name of the first article in the group and the name of the current newsgroup
current newsgroup MUST be set to the selected newsgroup MUST be set to the selected newsgroup name. If an invalid group is
name. If an invalid group is specified, the previously specified, the previously selected group and article remain
selected group and article remain selected. If an empty selected. If an empty newsgroup is selected, the "current article
newsgroup is selected, the "current article pointer" may be pointer" may be in an indeterminate state and should not be used.
in an indeterminate state and should not be used.
The LISTGROUP keyword MAY be used by a client as a The LISTGROUP keyword MAY be used by a client as a replacement for
replacement for the GROUP command in establishing a valid the GROUP command in establishing a valid "current article pointer."
"current article pointer." After a successful response is After a successful response is received, any other command may be
received, any other command may be used that depends on used that depends on having the "current article pointer" be valid.
having the "current article pointer" be valid.
The group name MUST match a newsgroup obtained from the If a group name is specified and that group is not available on that
LIST command or an error will result, else the server will server, the server MUST respond with the 411 error code.
respond with the 411 error code.
A server that does not implement this command SHOULD return A server that does not implement this command SHOULD return a 500
a 500 error response. error response.
9.5.1.1.1 Responses 9.5.1.1.1 Responses
211 list of article numbers follow 211 List of article numbers follow (multi-line
response)
411 No such group 411 No such group
412 Not currently in newsgroup 412 No newsgroup currently selected
500 Command not recognized 500 Command not recognized
9.5.1.1.2 Examples 9.5.1.1.2 Examples
Example of a successful execution with a group that exists on Example of LISTGROUP on an empty group:
the server
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LISTGROUP misc.test [C] LISTGROUP example.empty.newsgroup
[S] 211 list of article numbers follow [S] 211 list of article numbers follows
[S] .
Barber [Page 42]
INTERNET DRAFT S. Barber Example of LISTGROUP on a valid current group:
Expires: October 30, 2001 Academ Consulting Services [S] 200 NNTP Service Ready
March 2001 [C] GROUP misc.test
[S] 211 2000 3000234 3002322 misc.test selected
[C] LISTGROUP
[S] 211 list follows
[S] 3000234 [S] 3000234
[S] 3000237 [S] 3000237
[S] 3000238 [S] 3000238
[S] 3000239 [S] 3000239
[S] 3002322 [S] 3002322
[S] . [S] .
Example of an unsuccessful execution with a group that does Example of LISTGROUP failing because no group has been selected:
not exist on the server
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LISTGROUP this.group.is.not.here [C] LISTGROUP
[S] 411 no such group [S] 412 no current group
[C] GROUP example.is.sob.bradner.or.barber
Example of an attempt to retrieve an article when the current Barber Page [29]
group selected is empty
[S] 200 NNTP Service Ready INTERNET DRAFT S. Barber
[C] LISTGROUP example.empty.newsgroup Expires: May 15, 2002 Academ Consulting Services
[S] 412 No current article selected November 2001
[S] 411 no such group
[C] LISTGROUP
[S] 412 no current group
9.5.2 The OVER Extension 9.5.2 The OVER Extension
This extension provides two commands, OVER and LIST This extension provides two commands, OVER and LIST OVERVIEW.FMT. The
OVERVIEW.FMT. The label for this extension is OVER. label for this extension is OVER.
9.5.2.1 LIST OVERVIEW.FMT 9.5.2.1 LIST OVERVIEW.FMT
LIST OVERVIEW.FMT LIST OVERVIEW.FMT
The overview.fmt file is maintained by some news transport The overview.fmt file is maintained by some news transport systems to
systems to contain the order in which header information is contain the order in which header information is stored in the
stored in the overview databases for each newsgroup. When overview databases for each newsgroup. When executed, news article
executed, news article header fields are displayed one line at header fields are displayed one line at a time in the order in which
a time in the order in which they are stored in the overview they are stored in the overview database[6] following the 215
database[6] following the 215 response. When display is response. When display is completed, the server will send a period on
completed, the server will send a period on a line by itself. a line by itself. If the information is not available, the server will
return the 503 response.
If the information is not available, the server will return
the 503 response.
If the header has the word "full" (without quotes) after the
colon, the header's name is prepended to its field in the
output returned by the server.
This is command is part of the optional OVER extension which
includes the OVER command defined in section . If the OVER
Barber [Page 43] If the header has the word "full" (without quotes) after the colon,
the header's name is prepended to its field in the output returned by
the server.
INTERNET DRAFT S. Barber This is command is part of the optional OVER extension which includes
Expires: October 30, 2001 Academ Consulting Services the OVER command defined in section . If the OVER extension is not
March 2001 implemented, then this command MUST NOT be implemented. If that case,
extension is not implemented, then this command MUST NOT be the server MUST return a 501 error response when this command is
implemented. If that case, the server MUST return a 501 error presented by the client.
response when this command is presented by the client.
9.5.2.1.1 Responses 9.5.2.1.1 Responses
215 information follows 215 Information follows (multi-line response)
501 Syntax Error 501 Syntax Error
503 program error, function not performed 503 Program error, function not performed
9.5.2.1.2 Examples 9.5.2.1.2 Examples
Example of LIST OVERVIEW.FMT returning a list of newsgroups Example of LIST OVERVIEW.FMT returning a list of newsgroups
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LIST OVERVIEW.FMT [C] LIST OVERVIEW.FMT
[S] 215 Order of fields in overview database. [S] 215 Order of fields in overview database.
[S] Subject: [S] Subject:
[S] From: [S] From:
[S] Date: [S] Date:
skipping to change at line 2155 skipping to change at line 2024
[S] . [S] .
Example of LIST OVERVIEW.FMT returning an error Example of LIST OVERVIEW.FMT returning an error
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] LIST OVERVIEW.FMT [C] LIST OVERVIEW.FMT
[S] 503 program error, function not performed [S] 503 program error, function not performed
9.5.2.2 OVER 9.5.2.2 OVER
OVER [range] OVER [range]
The OVER command returns specific header information for the The OVER command returns specific header information for the
article(s) specified from the current selected group. The article(s) specified from the current selected group. The information
information returned in the response to this command can be
used by clients to follow discussion threads.
The optional range argument may be any of the following:
. an article number
. an article number followed by a dash to indicate all
following
Barber [Page 44] Barber Page [30]
INTERNET DRAFT S. Barber INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services Expires: May 15, 2002 Academ Consulting Services
March 2001 November 2001
. an article number followed by a dash followed by another
returned in the response to this command can be used by clients to
follow discussion threads.
The optional range argument may be any of the following:
o an article number
o an article number followed by a dash to indicate all
following
o an article number followed by a dash followed by another
article number article number
If no argument is specified, then information from the current If no argument is specified, then information from the current article
article is displayed. Successful responses start with a 224 is displayed. Successful responses start with a 224 response followed
response followed by the overview information for all matched by the overview information for all matched messages. Once the output
messages. Once the output is complete, a period is sent on a is complete, a period is sent on a line by itself. If no argument is
line by itself. If no argument is specified, the information specified, the information for the current article is returned. A
for the current article is returned. A newsgroup must have newsgroup must have been selected earlier, else a 412 error response
been selected earlier, else a 412 error response is returned. is returned. If no articles are in the range specified, the server
If no articles are in the range specified, the server returns returns a 420 error response. A 502 response will be returned if the
a 420 error response. A 502 response will be returned if the client only has permission to transfer articles. A 500 response SHOULD
client only has permission to transfer articles. A 500 be returned by servers do not implement this command.
response SHOULD be returned by servers do not implement this
command. The output consists of one line per article, sorted in numerical order
of article number. Each line consists of a number of fields separated
by an US-ASCII TAB character. The first 8 fields MUST be the
following, in order:
The output consists of one line per article, sorted in
numerical order of article number. Each line consists of a
number of fields separated by an US-ASCII TAB character. The
first 8 fields MUST be the following, in order:
article number, subject, author, date, message-ID, references, article number, subject, author, date, message-ID, references,
byte count, line count byte count, line count.
The content of any subsequent field is given by the response The content of each field is formed by taking the original content
to the LIST OVERVIEW.FMT command. A field may be empty (in (such as the raw subject line from the article), removing all US-ASCII
which case there will be two adjacent US-ASCII tabs, and a CRLF pairs, and then replacing each remaining US-ASCII NUL, TAB, CR,
sequence of trailing US-ASCII tabs may be omitted). Any or LF character with a single US-ASCII space.
sequence of US-ASCII space or non-printing characters in a
field MUST be replaced by a single US-ASCII space.
The server SHOULD not produce output for articles that no The content of any subsequent field is given by the response to the
longer exist. LIST OVERVIEW.FMT command. A field may be empty (in which case there
will be two adjacent US-ASCII tabs, and a sequence of trailing
US-ASCII tabs may be omitted).
The server SHOULD not produce output for articles that no longer
exist.
9.5.2.2.1 Responses 9.5.2.2.1 Responses
224 Overview information follows 224 Overview information follows (multi-line
412 No newsgroup current selected response)
412 No newsgroup currently selected
420 No article(s) selected 420 No article(s) selected
500 Command not recognized 500 Command not recognized
502 Service Unavailable 502 Program error, functions no performed
9.5.2.2.2 Examples 9.5.2.2.2 Examples
Example of a successful retrieval of overview information for Example of a successful retrieval of overview information for an article
an article (using no article number) (using no article number)
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
Barber [Page 45]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] OVER [C] OVER
[S] 224 Overview information follows [S] 224 Overview information follows
300234|I am just a test article|nobody@nowhere.to 300234|I am just a test article|nobody@nowhere.to
(Demo User)|6 Oct 1998 04:38:40 -0500| (Demo User)|6 Oct 1998 04:38:40 -0500|
<45223423@to.to> <45223423@to.to>
[S] . [S] .
[Please note that the line that begins with 300234 is all one [Please note that the line that begins with 300234 is all one line that
line that has been wrapped for readability. A vertical bar has has been wrapped for readability. A vertical bar has been inserted to
been inserted to show where the US-ASCII TAB should actually
be.]
Example of an unsuccessful retrieval of overview information Barber Page [31]
on an article by number
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
show where the US-ASCII TAB should actually be.]
Example of an unsuccessful retrieval of overview information on an
article by number
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] OVER 300256 [C] OVER 300256
[S] 420 No such article in this group [S] 420 No such article in this group
Example of an unsuccessful retrieval of overview information Example of an unsuccessful retrieval of overview information by number
by number because no newsgroup was selected first because no newsgroup was selected first
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] OVER [C] OVER
[S] 412 No newsgroup selected [S] 412 No newsgroup selected
Example of an attempt to retrieve an article when the current Example of an attempt to retrieve an article when the current group
group selected is empty selected is empty
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP example.empty.newsgroup [C] GROUP example.empty.newsgroup
[S] 211 0 0 0 example.empty.newsgroup [S] 211 0 0 0 example.empty.newsgroup
[C] OVER [C] OVER
[S] 420 No current article selected [S] 420 No current article selected
9.5.3 The HDR Extension 9.5.3 The HDR Extension
This extension provides one new command, HDR. The label for
this extension is PAT.
Barber [Page 46] This extension provides one new command, HDR. The label for this
extension is PAT.
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
9.5.3.1 HDR 9.5.3.1 HDR
HDR range|<message-id> HDR range|<message-id>
The HDR command is used to retrieve specific headers from The HDR command is used to retrieve specific headers from specific
specific articles in the currently selected group. articles in the currently selected group.
The required header parameter is the name of a header line (e.g.
The required header parameter is the name of a header line "subject") in a newsgroup article. See RFC-1036 for a list of valid
(e.g. "subject") in a newsgroup article. See RFC-1036 for a header lines. The required range argument may be any of the following:
list of valid header lines. The required range argument may be o an article number
any of the following: o an article number followed by a dash to indicate all
. an article number
. an article number followed by a dash to indicate all
following following
. an article number followed by a dash followed by another o an article number followed by a dash followed by another
article number. article number.
The required message-id argument indicates a specific article. The required message-id argument indicates a specific article. The
The range and message-id arguments are mutually exclusive. range and message-id arguments are mutually exclusive.
A successful response consists of a 221 code followed by the A successful response consists of a 221 code followed by the output
output from the command. The output consists of one line for from the command. The output consists of one line for each article
each article where the relevant header line exists. The line where the relevant header line exists. The line consists of the
consists of the article number, a US-ASCII space, and then the article number, a US-ASCII space, and then the contents of the header
contents of the header (without the header name). A valid (without the header name). A valid response includes an empty list
response includes an empty list (indicating that there were no (indicating that there were no matches). Once the output is complete,
matches). Once the output is complete, a period is sent on a a period is sent on a line by itself. If the optional argument is a
line by itself. If the optional argument is a message-id and message-id and no such article exists, a 430 error response shall be
no such article exists, a 430 error response shall be returned. A 502 response shall be returned if the client only has
returned. A 502 response shall be returned if the client only permission to transfer articles. A 500 response SHOULD be issued by
has permission to transfer articles. A 500 response SHOULD be all servers that do not recognize this command.
issued by all servers that do not recognize this command.
9.5.3.1.1 Responses 9.5.3.1.1 Responses
221 Header follows 221 Header follows (multi-line response)
412 no newsgroup selected 412 No newsgroup selected
430 no such article
500 Command not recognized
502 Service Unavailable
9.5.3.1.2 Examples Barber Page [32]
Example of a successful retrieval of subject lines from a INTERNET DRAFT S. Barber
range of articles Expires: May 15, 2002 Academ Consulting Services
November 2001
430 No such article
500 Command not recognized
502 Program error, function not performed
Barber [Page 47] 9.5.3.1.2 Examples
INTERNET DRAFT S. Barber Example of a successful retrieval of subject lines from a range of
Expires: October 30, 2001 Academ Consulting Services articles
March 2001
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] HDR Subject 3000234-300238 [C] HDR Subject 3000234-300238
[S] 221 Header Follows [S] 221 Header Follows
[S] 3000234 I am just a test article [S] 3000234 I am just a test article
[S] 3000237 Re: I am just a test article [S] 3000237 Re: I am just a test article
[S] 3000238 Ditto [S] 3000238 Ditto
[S] . [S] .
Example of a successful retrieval of header from an article by Example of a successful retrieval of header from an article by message-id
message-id
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP misc.test [C] GROUP misc.test
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] HDR subject <i.am.a.test.article@nowhere.to> [C] HDR subject <i.am.a.test.article@nowhere.to>
[S] 221 Header information follows [S] 221 Header information follows
[S] 3000345 I am just a test article [S] 3000345 I am just a test article
[S] . [S] .
Example of an unsuccessful retrieval of a header from an Example of an unsuccessful retrieval of a header from an article by
article by message-id message-id
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] HDR subject <i.am.not.there@nowhere.to> [C] HDR subject <i.am.not.there@nowhere.to>
[S] 430 No Such Article Found [S] 430 No Such Article Found
Example of an unsuccessful retrieval of headers from articles Example of an unsuccessful retrieval of headers from articles by number
by number because no newsgroup was selected first because no newsgroup was selected first
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] HDR subject 300256- [C] HDR subject 300256-
[S] 412 No newsgroup selected [S] 412 No newsgroup selected
Example of an unsuccessful retrieval of headers from articles Example of an unsuccessful retrieval of headers from articles by
by message-id because no newsgroup was selected first message-id because no newsgroup was selected first
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] HDR subject <i.am.a.test.article@nowhere.to> [C] HDR subject <i.am.a.test.article@nowhere.to>
[S] 412 No newsgroup selected [S] 412 No newsgroup selected
Barber [Page 48] Example of retrieving header information when the current group selected
is empty
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
Example of retrieving header information when the current
group selected is empty
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP example.empty.newsgroup [C] GROUP example.empty.newsgroup
[S] 211 0 0 0 example.empty.newsgroup [S] 211 0 0 0 example.empty.newsgroup
[C] HDR subject 0- [C] HDR subject 0-
[S] 221 Headers follow [S] 221 Headers follow
. .
Example of a failure due to restrictions configured into the Barber Page [33]
server
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
Example of a failure due to restrictions configured into the server
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] GROUP news.group [C] GROUP news.group
[S] 211 1234 3000234 3002322 misc.test [S] 211 1234 3000234 3002322 misc.test
[C] HDR Subject 3000234-300238 [C] HDR Subject 3000234-300238
[S] 502 Service Unavailable [S] 502 Service Unavailable
10. The CONCLUSION Step 10. The CONCLUSION Step
10.1 QUIT 10.1 QUIT
QUIT QUIT
The server process MUST acknowledge the QUIT command and then The server process MUST acknowledge the QUIT command and then close
close the connection to the client. This is the preferred the connection to the client. This is the preferred method for a
method for a client to indicate that it has finished all its client to indicate that it has finished all its transactions with the
transactions with the NNTP server. NNTP server.
If a client simply disconnects (or the connection times out or If a client simply disconnects (or the connection times out or some
some other fault occurs), the server MUST gracefully cease its other fault occurs), the server MUST gracefully cease its attempts to
attempts to service the client, disconnecting from its end if service the client, disconnecting from its end if necessary.
necessary.
10.1.1 Responses 10.1.1 Responses
205 closing connection - goodbye! 250 Connection closing
10.1.2 Example 10.1.2 Example
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] QUIT [C] QUIT
[S] 205 closing connection [S] 205 closing connection
Barber [Page 49]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
[Server closes connection.] [Server closes connection.]
11. Other Keywords 11. Other Keywords
There are other keywords that may be used at any time between There are other keywords that may be used at any time between the
the beginning of a session and its termination. Using these beginning of a session and its termination. Using these keywords does
keywords does not alter any state information, but the not alter any state information, but the response generated from the
response generated from the use of these keywords may provide use of these keywords may provide useful information to clients that
useful information to clients that use them. use them.
11.1 DATE 11.1 DATE
DATE DATE
This command exists to help clients find out the current Coordinated
Universal Time[7] from the server's perspective. This command
SHOULD NOT be used as a substitute for NTP[8], but to provide
information that might be useful when using the NEWNEWS command (see
section 11.4). A system providing NNTP service SHOULD implement NTP
for the purposes of keeping the system clock as accurate as possible.
This command returns a one-line response code of 111 followed by the
date and time on the server in the form YYYYMMDDhhmmss.
This command exists to help clients find out the current 11.1.1 Response
Coordinated Universal Time[7] from the server's perspective.
This command SHOULD NOT be used as a substitute for NTP[8],
but to provide information that might be useful when using the
NEWNEWS command (see section 11.4). A system providing NNTP
service SHOULD implement NTP for the purposes of keeping the
system clock as accurate as possible.
This command returns a one-line response code of 111 followed
by the date and time on the server in the form YYYYMMDDhhmmss.
11.1.1 Responses
111 YYYYMMDDhhmmss 111 YYYYMMDDhhmmss Local date on server
11.1.2 Example 11.1.2 Example
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] DATE [C] DATE
Barber Page[34]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
[S] 111 19990623135624 [S] 111 19990623135624
11.2 The HELP Command 11.2 The HELP Command
HELP HELP
This command provides a short summary of commands that are understood
by this implementation of the server. The help text will be presented
as a textual response terminated by a single period on a line by
itself.
This command provides a short summary of commands that are This text is not guaranteed to be in any particular format and SHALL
understood by this implementation of the server. The help text NOT be used by clients as a replacement for the LIST EXTENSIONS
will be presented as a textual response terminated by a single command described in section 8.1.
period on a line by itself.
This text is not guaranteed to be in any particular format and
SHALL NOT be used by clients as a replacement for the LIST
EXTENSIONS command described in section 8.1.
Barber [Page 50]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
11.2.1 Responses 11.2.1 Responses
100 help text follows 100 Help text follows (multi-line response)
11.2.2 Example 11.2.2 Example
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] HELP [C] HELP
[S] 100 Help text follows [S] 100 Help text follows
[S] This is some help text. There is no specific [S] This is some help text. There is no specific
[S] formatting requirement for this test, though [S] formatting requirement for this test, though
[S] it is customary for it to list the valid commands [S] it is customary for it to list the valid commands
[S] and give a brief definition of what they do [S] and give a brief definition of what they do
[S] . [S] .
11.3 NEWGROUPS 11.3 NEWGROUPS
NEWGROUPS date time [GMT] NEWGROUPS date time [GMT]
A list of newsgroups created since <date and time> MUST be A list of newsgroups created since <date and time> MUST be listed in
listed in the same format as the LIST command. the same format as the LIST command.
The date is sent as 6 or 8 digits in the format [XX]YYMMDD, where XX
is the first two digits of the year, YY is the last two digits of the
year, MM is the two digits of the month (with leading zero, if
appropriate), and DD is the day of the month (with leading zero, if
appropriate). If the first two digits of the year are not specified,
the year is to be taken from the current century if YY is smaller than
or equal to the current year, otherwise the year is from the previous
century.
The date is sent as 6 or 8 digits in the format [XX]YYMMDD, Time must also be specified. It must be as 6 digits HHMMSS with HH
where XX is the first two digits of the year, YY is the last being hours in the 24-hour clock 00-23, MM minutes 00-59, and SS
two digits of the year, MM is the two digits of the month seconds 00-60, which allows for leap seconds. The token "GMT"
(with leading zero, if appropriate), and DD is the day of the specifies that the date and time are given in Coordinated Universal
month (with leading zero, if appropriate). If the first two Time. If the token "GMT" is omitted then the date and time are
digits of the year are not specified, the year is to be taken specified in the server's local timezone. Note that there is no way
from the current century if YY is smaller than or equal to the within this specification of NNTP to establish the server's local
current year, otherwise the year is from the previous century. timezone.
Time must also be specified. It must be as 6 digits HHMMSS Note that an empty list (i.e., the text body returned by this command
with HH being hours in the 24-hour clock 00-23, MM minutes 00- consists only of the terminating period) is a possible valid response,
59, and SS seconds 00-60, which allows for leap seconds. The and indicates that there are currently no new newsgroups.
token "GMT" specifies that the date and time are given in
Coordinated Universal Time. If the token "GMT" is omitted then
the date and time are specified in the server's local
timezone. Note that there is no way within this specification
of NNTP to establish the server's local timezone.
Note that an empty list (i.e., the text body returned by this Clients SHOULD make all queries using Coordinated Universal Time when
command consists only of the terminating period) is a possible possible.
valid response, and indicates that there are currently no new
newsgroups.
Barber [Page 51] 11.3.1 Responses
INTERNET DRAFT S. Barber 231 List of new newsgroups follows (multi-line
Expires: October 30, 2001 Academ Consulting Services response)
March 2001
Clients SHOULD make all queries using Coordinated Universal
Time when possible.
11.3.1 Responses Barber Page [35]
231 list of new newsgroups follows INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
11.3.2 Examples 11.3.2 Examples
Example where there are new groups Example where there are new groups
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] NEWGROUPS 19990624 000000 GMT [C] NEWGROUPS 19990624 000000 GMT
[S] 230 list of new newsgroups follows [S] 231 list of new newsgroups follows
[S] alt.rfc-writers.recovery [S] alt.rfc-writers.recovery
[S] tx.natives.recovery [S] tx.natives.recovery
[S] . [S] .
Example where there are no new groups Example where there are no new groups
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] NEWGROUPS 19990624 000000 GMT [C] NEWGROUPS 19990624 000000 GMT
[S] 230 list of new newsgroups follows [S] 231 list of new newsgroups follows
[S] . [S] .
11.4 NEWNEWS 11.4 NEWNEWS
NEWNEWS newsgroups date time [GMT] NEWNEWS newsgroups date time [GMT]
A list of message-ids of articles posted or received to the A list of message-ids of articles posted or received to the specified
specified newsgroup or groups since "date" will be listed. The newsgroup or groups since "date" will be listed. The format of the
format of the listing will be one message-id per line, as listing will be one message-id per line, as though text were being
though text were being sent. Each message-id SHALL appear only sent. Each message-id SHALL appear only once in a response. The order
once in a response. The order of the response has no specific of the response has no specific significance and may vary from
significance and may vary from response to response in the response to response in the same session. A single line consisting
same session. A single line consisting solely of one period solely of one period followed by CR-LF will terminate the list.
followed by CR-LF will terminate the list.
Date and time are in the same format as the NEWGROUPS command.
The newsgroups parameter MUST be in wildmat format and MAY
consist of multiple wildmat constructs separated by an US-
ASCII comma character.
Note that an empty list (i.e., the text body returned by this Date and time are in the same format as the NEWGROUPS command. The
command consists only of the terminating period) is a possible newsgroups parameter MUST be in wildmat format and MAY consist of
valid response, and indicates that there is currently no new multiple wildmat constructs separated by an US-ASCII comma character.
news.
Barber [Page 52] Note that an empty list (i.e., the text body returned by this command
consists only of the terminating period) is a possible valid response,
and indicates that there is currently no new news.
INTERNET DRAFT S. Barber Clients SHOULD make all queries in Coordinated Universal Time when
Expires: October 30, 2001 Academ Consulting Services possible.
March 2001
Clients SHOULD make all queries in Coordinated Universal Time
when possible.
11.4.1 Responses 11.4.1 Responses
230 list of new articles by message-id follows 230 List of new articles by message-id follows (may be a
multi-line response)
11.4.2 Examples 11.4.2 Examples
Example where there are new articles Example where there are new articles
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] NEWNEWS news.*,sci.* 19990624 000000 [C] NEWNEWS news.*,sci.* 19990624 000000
[S] 230 list of new articles by message-id follows [S] 230 list of new articles by message-id follows
[S] <i.am.a.new.article@nowhere.to> [S] <i.am.a.new.article@nowhere.to>
[S] <i.am.another.new.article@nowhere.to> [S] <i.am.another.new.article@nowhere.to>
Example where there are no new articles Example where there are no new articles
[S] 200 NNTP Service Ready [S] 200 NNTP Service Ready
[C] NEWNEWS alt.* 19990624 000000 [C] NEWNEWS alt.* 19990624 000000
[S] 230 list of new articles by message-id follows [S] 230 list of new articles by message-id follows
Barber Page [36]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
[S] . [S] .
12. Framework for NNTP Extensions 12. Framework for NNTP Extensions
Although NNTP is widely and robustly deployed, some parts of Although NNTP is widely and robustly deployed, some parts of the
the Internet community might wish to extend the NNTP service. Internet community might wish to extend the NNTP service. This memo
This memo defines a means whereby an extended NNTP client may defines a means whereby an extended NNTP client may query the server
query the server to determine the service extensions that it to determine the service extensions that it supports.
supports.
It must be emphasized that any extension to the NNTP service It must be emphasized that any extension to the NNTP service should
should not be considered lightly. NNTP's strength comes not be considered lightly. NNTP's strength comes primarily from its
primarily from its simplicity. Experience with many protocols simplicity. Experience with many protocols has shown that:
has shown that:
Protocols with few options tend towards ubiquity, whilst Protocols with few options tend towards ubiquity, whilst protocols
protocols with many options tend towards obscurity. with many options tend towards obscurity.
This means that each and every extension, regardless of its This means that each and every extension, regardless of its benefits,
benefits, must be carefully scrutinized with respect to its must be carefully scrutinized with respect to its implementation,
implementation, deployment, and interoperability costs. In deployment, and interoperability costs. In many cases, the cost of
many cases, the cost of extending the NNTP service will likely extending the NNTP service will likely outweigh the benefit.
outweigh the benefit.
Barber [Page 53] Given this environment, the framework for the extensions described in
this memo consists of:
INTERNET DRAFT S. Barber a)a mechanism for clients to determine a server's available extensions
Expires: October 30, 2001 Academ Consulting Services
March 2001
Given this environment, the framework for the extensions
described in this memo consists of:
a)a mechanism for clients to determine a server's available
extensions
b)a registry of NNTP service extensions b)a registry of NNTP service extensions
The LIST EXTENSIONS command is described in section 8.1 of The LIST EXTENSIONS command is described in section 8.1 of this memo
this memo and is the mechanism for clients to use to determine and is the mechanism for clients to use to determine what extensions
what extensions are available for client use. are available for client use.
The IANA shall maintain a registry of NNTP service extensions. The IANA shall maintain a registry of NNTP service extensions.
An extension is identified by a unique extension-label, which
is a string of 1 to 12 uppercase letters. The extension-label
will often be the name of a new command that the extension
adds. However this is not a requirement: an extension might
not add any new commands or keywords.
An extension is either a private extension or else it is An extension is identified by a unique extension-label, which is a
included in the IANA registry and is defined in an RFC. Such string of 1 to 12 uppercase letters. The extension-label will often be
RFCs either must be on the standards-track or must define an the name of a new command that the extension adds. However this is not
IESG-approved experimental protocol. a requirement: an extension might not add any new commands or
keywords.
An extension is either a private extension or else it is included in
the IANA registry and is defined in an RFC. Such RFCs either must be
on the standards-track or must define an IESG-approved experimental
protocol.
The definition of an extension must include: The definition of an extension must include:
. a descriptive name for the extension o a descriptive name for the extension
. the extension-label (which is returned by LIST EXTENSIONS o the extension-label (which is returned by LIST EXTENSIONS
to indicate to the client that the server supports this to indicate to the client that the server supports this
particular extension) particular extension)
. the syntax, values, and meanings of any parameters o the syntax, values, and meanings of any parameters
following the extension-label in the output of LIST following the extension-label in the output of LIST EXTENSIONS
EXTENSIONS o any new NNTP keywords associated with the extension
. any new NNTP keywords associated with the extension o the syntax and possible values of parameters associated
. the syntax and possible values of parameters associated
with the new NNTP keywords with the new NNTP keywords
. any new parameters the extension associates with any o any new parameters the extension associates with any other
other pre-existing NNTP keywords pre-existing NNTP keywords
. how support for the extension affects the behavior of a o how support for the extension affects the behavior of a
server and NNTP client server and NNTP client
. any increase in the maximum length of commands over the o any increase in the maximum length of commands over the
value specified in this memo value specified in this memo
The extension-label of private extensions MUST begin with "X". The extension-label of private extensions MUST begin with "X". The
The extension-label of registered extensions MUST NOT begin extension-label of registered extensions MUST NOT begin with "X".
with "X".
Any keyword values presented in the NNTP response that do not Any keyword values presented in the NNTP response that do not begin
begin with "X" MUST correspond to a standard, standards-track, with "X" MUST correspond to a standard, standards-track, or
IESG-approved experimental NNTP service extension registered with
IANA. A conforming server MUST NOT offer non "X" prefixed keyword
values that are not described in a registered extension.
Barber [Page 54] Except where stated otherwise, the commands in this document are
understood (even if not supported) by all servers and are not
described in the list of features returned by the LIST EXTENSIONS
command.
INTERNET DRAFT S. Barber Barber Page [37]
Expires: October 30, 2001 Academ Consulting Services
March 2001
or IESG-approved experimental NNTP service extension
registered with IANA. A conforming server MUST NOT offer non
"X" prefixed keyword values that are not described in a
registered extension.
Except where stated otherwise, the commands in this document INTERNET DRAFT S. Barber
are understood (even if not supported) by all servers and are Expires: May 15, 2002 Academ Consulting Services
not described in the list of features returned by the LIST November 2001
EXTENSIONS command. A server MAY provide additional keywords - either new commands or new
parameters to existing commands - as part of a private extension.
A server MAY provide additional keywords - either new commands These new keywords MUST begin with "X".
or new parameters to existing commands - as part of a private
extension. These new keywords MUST begin with "X".
A server MUST NOT send different response codes to basic NNTP A server MUST NOT send different response codes to basic NNTP commands
commands documented here or commands documented in registered documented here or commands documented in registered extensions in
extensions in response to the availability or use of a private response to the availability or use of a private extension.
extension.
12.1 Initial IANA Registry 12.1 Initial IANA Registry
The IANA's initial registry of NNTP service extensions The IANA's initial registry of NNTP service extensions consists of
consists of these entries: these entries:
Service Extension NNTP Extension Label Added Behavior Service Extension NNTP Extension Label Added Behavior
Overview Support OVER Defined in this Overview OVER Defined
Support in this
document
Specific Article Numbers LISTGROUP Defined
in this
document
Header Pattern Matching HDR Defined
in this
document document
Specific Article LISTGROUP Defined in this
Numbers document
Header Pattern HDR Defined in this
Matching document
13. Augmented BNF[9] Syntax for NNTP Commands 13. Augmented BNF[9] Syntax for NNTP Commands
This syntax defines the non-terminal "command". The non-terminal This syntax defines the non-terminal "command". The non-terminal
"parameter" is used for command parameters whose syntax is "parameter" is used for command parameters whose syntax is specified
specified elsewhere. The syntax is in alphabetical order. Note elsewhere. The syntax is in alphabetical order. Note that ABNF strings
that ABNF strings are case insensitive. are case insensitive.
article-command = "ARTICLE" [1*WSP (msg-id / article-number)] *WSP
article-command = "ARTICLE" [1*WSP (msg-id / article-number)] CRLF
*WSP CRLF
article-number = 1*16DIGIT article-number = 1*16DIGIT
argument = parameter ; excluding sequence ".." argument = parameter ; excluding sequence ".."
body-command = "BODY" [1*WSP (msg-id / article-number)] *WSP body-command = "BODY" [1*WSP (msg-id / article-number)] *WSP CRLF
CRLF
command = article-command / command = article-command /
body-command / body-command /
Barber [Page 55]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
date-command / date-command /
group-command / group-command /
head-command / head-command /
help-command / help-command /
ihave-command / ihave-command /
last-command / last-command /
list-active-times-command / list-active-times-command /
list-distrib-pats-command / list-distrib-pats-command /
list-distributions-command / list-distributions-command /
list-extensions-command / list-extensions-command /
skipping to change at line 2746 skipping to change at line 2583
hdr-command / hdr-command /
post-command / post-command /
quit-command / quit-command /
stat-command stat-command
CR = %x0D CR = %x0D
CRLF = CR LF CRLF = CR LF
date-command = "DATE" *WSP CRLF date-command = "DATE" *WSP CRLF
date = 6*8DIGIT date = 6*8DIGIT
DIGIT = %x30-39 DIGIT = %x30-39
group-command = "GROUP" 1*WSP newsgroup *WSP CRLF group-command = "GROUP" 1*WSP newsgroup *WSP CRLF
hdr-command = "PAT" 1*WSP header 1*WSP (range / msg-id) *WSP hdr-command = "PAT" 1*WSP header 1*WSP (range / msg-id) *WSP CRLF
CRLF head-command = "HEAD" [1*WSP (msg-id / article-number)] *WSP CRLF
head-command = "HEAD" [1*WSP (msg-id / article-number)] *WSP
CRLF Barber Page[38]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
header = parameter header = parameter
help-command = "HELP" *WSP CRLF help-command = "HELP" *WSP CRLF
HT = %x09 HT = %x09
ihave-command = "IHAVE" 1*WSP msg-id *WSP CRLF ihave-command = "IHAVE" 1*WSP msg-id *WSP CRLF
last-command = "LAST" *WSP CRLF last-command = "LAST" *WSP CRLF
LF = %x0A LF = %x0A
list-active-times-command = "LIST" 1*WSP "ACTIVE.TIMES" list-active-times-command = "LIST" 1*WSP "ACTIVE.TIMES"
[1*WSP wildmat] *WSP CRLF [1*WSP wildmat] *WSP CRLF
list-command = "LIST" [1*WSP "ACTIVE" [1*WSP wildmat]] *WSP list-command = "LIST" [1*WSP "ACTIVE" [1*WSP wildmat] *WSP CRLF
CRLF list-distrib-pats-command = "LIST" 1*WSP "DISTRIB.PATS" *WSP CRLF
list-distrib-pats-command = "LIST" 1*WSP "DISTRIB.PATS" *WSP list-distributions-command = "LIST" 1*WSP "DISTRIBUTIONS" *WSP CRLF
CRLF
list-distributions-command = "LIST" 1*WSP "DISTRIBUTIONS" *WSP
CRLF
Barber [Page 56]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
list-extensions-command = "LIST" 1*WSP "EXTENSIONS" *WSP CRLF list-extensions-command = "LIST" 1*WSP "EXTENSIONS" *WSP CRLF
list-newsgroups-command = "LIST" 1*WSP "NEWSGROUPS" [1*WSP list-newsgroups-command = "LIST" 1*WSP "NEWSGROUPS" [1*WSP wildmat]
wildmat]
*WSP CRLF *WSP CRLF
list-overview-fmt-command = "LIST" 1*WSP "OVERVIEW.FMT" *WSP list-overview-fmt-command = "LIST" 1*WSP "OVERVIEW.FMT" *WSP CRLF
CRLF
listgroup-command = "LISTGROUP" [1*WSP newsgroup] *WSP CRLF listgroup-command = "LISTGROUP" [1*WSP newsgroup] *WSP CRLF
mode-reader-command = "MODE" 1*WSP "READER" *WSP CRLF mode-reader-command = "MODE" 1*WSP "READER" *WSP CRLF
msg-id = <defined in RFC822> msg-id = <defined in RFC2822>
newgroups-command = "NEWGROUPS" 1*WSP date 1*WSP time [1*WSP newgroups-command = "NEWGROUPS" 1*WSP date 1*WSP time [1*WSP
"GMT"] *WSP CRLF "GMT"/"UTC"] *WSP CRLF
newnews-command = "NEWNEWS" 1*WSP newsgroup *("," newsgroup) newnews-command = "NEWNEWS" 1*WSP newsgroup *("," newsgroup)
1*WSP date 1*WSP time [1*WSP "GMT"] 1*WSP date 1*WSP time [1*WSP "GMT"/"UTC"]
*WSP CRLF *WSP CRLF
newsgroup = parameter newsgroup = parameter
next-command = "NEXT" *WSP CRLF next-command = "NEXT" *WSP CRLF
over-command = "OVER" [1*WSP range] *WSP CRLF over-command = "OVER" [1*WSP range] *WSP CRLF
parameter = 1*(%x21-FF) ; generic command parameter parameter = 1*(%x21-FF) ; generic command parameter
post-command = "POST" *WSP CRLF post-command = "POST" *WSP CRLF
quit-command = "QUIT" *WSP CRLF quit-command = "QUIT" *WSP CRLF
range = article-number ["-" [article-number]] range = article-number ["-" [article-number]]
SP = %x20 SP = %x20
stat-command = "STAT" [1*WSP (msg-id / article-number)] *WSP stat-command = "STAT" [1*WSP (msg-id / article-number)] *WSP CRLF
CRLF
time = 6DIGIT time = 6DIGIT
UTF-8-non-ascii = UTF8-2 / UTF8-3 / UTF8-4 / UTF8-5 / UTF8-6 UTF-8-non-ascii = UTF8-2 / UTF8-3 / UTF8-4 / UTF8-5 / UTF8-6
UTF8-1 = %x80-BF UTF8-1 = %x80-BF
UTF8-2 = %xC0-DF UTF8-1 UTF8-2 = %xC0-DF UTF8-1
UTF8-3 = %xE0-EF 2UTF8-1 UTF8-3 = %xE0-EF 2UTF8-1
UTF8-4 = %xF0-F7 3UTF8-1 UTF8-4 = %xF0-F7 3UTF8-1
UTF8-5 = %xF8-FB 4UTF8-1 UTF8-5 = %xF8-FB 4UTF8-1
UTF8-6 = %xFC-FD 5UTF8-1 UTF8-6 = %xFC-FD 5UTF8-1
wildmat = ["!"]1*("*" / "?" / wildmat-exact / wildmat-set / wildmat = ["!"]1*("*" / "?" / wildmat-exact / wildmat-set /
"\" (%x22-7F / UTF-8-non-ascii)) "\" (%x22-7F / UTF-8-non-ascii))
wildmat-exact = %x22-29 / %x2B-3E / %x40-5A / %x5D-7F / UTF-8- wildmat-exact = %x22-29 / %x2B-3E / %x40-5A / %x5D-7F /
non-ascii ; exclude space ! * ? [ \ UTF-8-non-ascii ; exclude space ! * ? [ \
wildmat-non-hyphen = %x21-2C / %x2E-7F / UTF-8-non-ascii ; wildmat-non-hyphen = %x21-2C / %x2E-7F / UTF-8-non-ascii ; exclude
exclude space - space -
wildmat-set = "[" ["^"] ["]" / "-"] *(wildmat-non-hyphen"["-" wildmat-set = "[" ["^"] ["]" / "-"] *(wildmat-non-hyphen"["-"
wildmat-non-hyphen]) ["-"] wildmat-non-hyphen]) ["-"]
WSP = SP / HT WSP = SP / HT
14. Security Considerations 14. Security Considerations
This section is meant to inform application developers, This section is meant to inform application developers, information
information providers, and users of the security limitations providers, and users of the security limitations in NNTP as described
in NNTP as described by this document. The discussion does not by this document. The discussion does not include definitive solutions
to the problems revealed, though it does make some suggestions for
Barber [Page 57] reducing security risks.
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
include definitive solutions to the problems revealed, though
it does make some suggestions for reducing security risks.
14.1 Personal and Proprietary Information 14.1 Personal and Proprietary Information
NNTP, because it was created to distribute network news NNTP, because it was created to distribute network news articles, will
articles, will forward whatever information is stored in those forward whatever information is stored in those articles.
articles. Specification of that information is outside this Specification of that information is outside this scope of this
scope of this document, but it is likely that some personal document, but it is likely that some personal and/or proprietary
and/or proprietary information is available in some of those information is available in some of those articles. It is very
articles. It is very important that designers and implementers important that designers and implementers provide informative warnings
provide informative warnings to users so personal and/or to users so personal and/or proprietary information is not disclosed
proprietary information is not disclosed inadvertently. inadvertently. Additionally, effective and easily understood
mechanisms to manage the distribution of news articles must be
Additionally, effective and easily understood mechanisms to provided to NNTP Server administrators, so that they are able to
manage the distribution of news articles must be provided to report with confidence what information is and is not being forwarded
NNTP Server administrators, so that they are able to report
with confidence what information is and is not being forwarded
in news articles passing though their servers. in news articles passing though their servers.
Barber Page [39]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
14.2 Abuse of Server Log Information 14.2 Abuse of Server Log Information
A server is in the position to save session data about a A server is in the position to save session data about a user's
user's requests that might identify their reading patterns or requests that might identify their reading patterns or subjects of
subjects of interest. This information is clearly confidential interest. This information is clearly confidential in nature and its
in nature and its handling can be constrained by law in handling can be constrained by law in certain countries. People using
certain countries. People using the NNTP protocol to provide the NNTP protocol to provide data are responsible for ensuring that
data are responsible for ensuring that such material is not such material is not distributed without the permission of any
distributed without the permission of any individuals that are individuals that are identifiable by the published results.
identifiable by the published results.
14.3 DNS Spoofing 14.3 Weak Authentication and Access Control
Clients and Servers using NNTP rely heavily on the Domain Name There is no user-based or token-based authentication in the basic NNTP
Service, and are thus generally prone to security attacks specification. Access is normally controlled by server configuration
based on the deliberate misassociation of IP addresses and DNS files. Those files specify access by using domain names or IP
names. Clients and Servers need to be cautious in assuming the addresses. However, this specification does permit the creation of
continuing validity of an IP number/DNS name association. extensions to the NNTP protocol itself for such purposes. While
including such mechanisms is optional, doing so is strongly
encouraged.
In particular, NNTP clients and servers SHOULD rely on their Other mechanisms are also available. For example, a proxy server could
name resolver for confirmation of an IP number/DNS name be put in place that requires authentication before connecting via the
association, rather than caching the result of previous host proxy to the NNTP server.
name lookups. Many platforms already can cache host name
lookups locally when appropriate, and they SHOULD be
configured to do so. It is proper for these lookups to be
cached, however, only when the TTL (Time To Live) information
reported by the name server makes it likely that the cached
information will remain useful.
Barber [Page 58] 14.4 DNS Spoofing
INTERNET DRAFT S. Barber Many existing NNTP implementations authorize incoming connections by
Expires: October 30, 2001 Academ Consulting Services checking the IP address of that connection against the IP addresses
March 2001 obtained via DNS lookups of lists of domain names given in local
If NNTP clients or servers cache the results of host name configuration files. Servers that use this type of authentication,
lookups in order to achieve a performance improvement, they and clients that find a server by doing a DNS lookup of the server
MUST observe the TTL information reported by DNS. name, rely very heavily on the Domain Name Service, and are thus
generally prone to security attacks based on the deliberate
misassociation of IP addresses and DNS names. Clients and servers
need to be cautious in assuming the continuing validity of an IP
number/DNS name association.
If NNTP clients or servers do not observe this rule, they In particular, NNTP clients and servers SHOULD rely on their name
could be spoofed when a previously accessed server's IP resolver for confirmation of an IP number/DNS name association, rather
address changes. As network renumbering is expected to become than caching the result of previous host name lookups. Many platforms
increasingly common, the possibility of this form of attack already can cache host name lookups locally when appropriate, and they
will grow. Observing this requirement thus reduces this SHOULD be configured to do so. It is proper for these lookups to be
potential security vulnerability. cached, however, only when the TTL (Time To Live) information reported
by the name server makes it likely that the cached information will
remain useful.
This requirement also improves the load-balancing behavior of If NNTP clients or servers cache the results of host name lookups in
clients for replicated servers using the same DNS name and order to achieve a performance improvement, they MUST observe the TTL
reduces the likelihood of a user's experiencing failure in information reported by DNS.
accessing sites that use that strategy.
14.4 Weak Authentication and Access Control If NNTP clients or servers do not observe this rule, they could be
spoofed when a previously accessed server's IP address changes. As
network renumbering is expected to become increasingly common, the
possibility of this form of attack will grow. Observing this
requirement thus reduces this potential security vulnerability.
There is no user-based or token-based authentication in the This requirement also improves the load-balancing behavior of clients
basic NNTP specification. Access is normally controlled by for replicated servers using the same DNS name and reduces the
server configuration files. Those files specify access by likelihood of a user's experiencing failure in accessing sites that
using domain names or IP addresses. However, this use that strategy.
specification does permit the creation of extensions to the
NNTP protocol itself for such purposes. While including such
mechanisms is optional, doing so is strongly encouraged.
Other mechanisms are also available. For example, a proxy
server could be put in place that requires authentication
before connecting via the proxy to the NNTP server.
15. References 15. References
[1] Kantor, B and P. Lapsley, "Network News Transfer Protocol", [1] Kantor, B and P. Lapsley, "Network News Transfer Protocol",
RFC-977, U.C. San Diego and U.C. Berkeley. RFC-977, U.C. San Diego and U.C. Berkeley.
[2] Yergeau, F., "UTF-8, a transformation format of ISO 10646", [2] Yergeau, F., "UTF-8, a transformation format of ISO 10646", RFC
RFC 2279, Alis Technologies. 2279, Alis Technologies.
[3] Coded Character Set-7-bit American Standard Code for [3] Coded Character Set-7-bit American Standard Code for Information
Information Interchange, ANSI x3.4-1986. Interchange, ANSI x3.4-1986.
[4]Bradner, Scott, "Keywords for use in RFCs to Indicate [4] Bradner, Scott, "Keywords for use in RFCs to Indicate Requirement
Requirement Levels", RFC-2119, Harvard University.
40]
INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
November 2001
Levels", RFC-2119, Harvard University.
[5] Salz, Rich, Manual Page for wildmat(3) from the INN 1.4 [5] Salz, Rich, Manual Page for wildmat(3) from the INN 1.4
distribution, UUNET Technologies, Revision 1.10, April, 1992. distribution, UUNET Technologies, Revision 1.10, April, 1992.
[6] Robertson, Rob, "FAQ: Overview database / NOV General [6] Robertson, Rob, "FAQ: Overview database / NOV General
Information", ftp://ftp.uu.net/networking/news/nntp/inn/faq- Information", ftp://ftp.uu.net/networking/news/nntp/inn/faq-nov.Z,
nov.Z, January, 1995. January, 1995.
[7] International Telecommunications Union-Radio, "Glossary", [7] International Telecommunications Union-Radio, "Glossary", ITU-R
ITU-R Recommendation TF.686-1, October, 1997. Recommendation TF.686-1, October, 1997.
[8] Mills, David L., "Network Time Protocol (Version 3), [8] Mills, David L., "Network Time Protocol (Version 3),
Specification, Implementation and Analysis", RFC-1305, Specification, Implementation and Analysis", RFC-1305, University of
University of Delaware, March 1992. Delaware, March 1992.
Barber [Page 59]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
[9] Crocker, D. and Overell, P., "Augmented BNF for Syntax [9] Crocker, D. and Overell, P., "Augmented BNF for Syntax
Specifications: ABNF", RFC-2234, Internet Mail Consortium and Specifications: ABNF", RFC-2234, Internet Mail Consortium and Demon
Demon Internet, Ltd. Internet, Ltd.
16. Notes 16. Notes
UNIX is a registered trademark of the X/Open Consortium. UNIX is a registered trademark of the X/Open Consortium.
17. Acknowledgments 17. Acknowledgments
The author acknowledges the original authors of NNTP as The author acknowledges the original authors of NNTP as documented in
documented in RFC 977: Brian Kantor and Phil Lapsey. RFC 977: Brian Kantor and Phil Lapsey.
The author gratefully acknowledges the work of the NNTP The author gratefully acknowledges the work of the NNTP committee
committee chaired by Eliot Lear. The organization of this chaired by Eliot Lear. The organization of this document was
document was influenced by the last available draft from this influenced by the last available draft from this working group. A
working group. A special thanks to Eliot for generously special thanks to Eliot for generously providing the original
providing the original machine-readable sources for that machine-readable sources for that document.
document.
The author gratefully acknowledges the work of the Marshall Rose &
John G. Meyers in RFC 1939 and the work of the DRUMS working group,
specifically RFC 1869, which is the basis of the NNTP extensions
mechanism detailed in this document.
The author gratefully acknowledges the work of the Marshall
Rose & John G. Meyers in RFC 1939 and the work of the DRUMS
working group, specifically RFC 1869, which is the basis of
the NNTP extensions mechanism detailed in this document.
The author gratefully acknowledges the authors of RFC 2616 for The author gratefully acknowledges the authors of RFC 2616 for
providing specific and relevant examples of security issues providing specific and relevant examples of security issues that
that should be considered for HTTP. Since many of the same should be considered for HTTP. Since many of the same considerations
considerations exist for NNTP, those examples that are exist for NNTP, those examples that are relevant have been included
relevant have been included here with some minor rewrites. here with some minor rewrites.
The author gratefully acknowledges the comments and additional The author gratefully acknowledges the comments and additional
information provided by the following individuals in preparing information provided by the following individuals in preparing one of
one of the progenitors of this document: the progenitors of this document:
o Russ Allbery <rra@stanford.edu>
. Russ Allbery <rra@stanford.edu> o Wayne Davison <davison@armory.com>
. Wayne Davison <davison@armory.com> o Clive D.W. Feather <clive@demon.net>
. Clive D.W. Feather <clive@demon.net> o Chris Lewis <clewis@bnr.ca>
. Chris Lewis <clewis@bnr.ca> o Tom Limoncelli <tal@mars.superlink.net>
. Tom Limoncelli <tal@mars.superlink.net> o Eric Schnoebelen <eric@egsner.cirr.com>
. Eric Schnoebelen <eric@egsner.cirr.com> o Rich Salz <rsalz@osf.org>
. Rich Salz <rsalz@osf.org>
Barber [Page 60]
INTERNET DRAFT S. Barber
Expires: October 30, 2001 Academ Consulting Services
March 2001
This work was motivated by the work of various news reader
authors and news server authors, which includes those listed
below:
. Rick Adams-Original author of the NNTP extensions to the This work was motivated by the work of various news reader authors and
RN news reader and last maintainer of Bnews news server authors, which includes those listed below:
. Stan Barber-Original author of the NNTP extensions to the o Rick Adams-Original author of the NNTP extensions to the RN
news reader and last maintainer of Bnews
o Stan Barber-Original author of the NNTP extensions to the
news readers that are part of Bnews. news readers that are part of Bnews.
. Geoff Collyer-Original author of the OVERVIEW database o Geoff Collyer-Original author of the OVERVIEW database
proposal and one of the original authors of CNEWS proposal and one of the original authors of CNEWS
. Dan Curry-Original author of the xvnews news reader o Dan Curry-Original author of the xvnews news reader
. Wayne Davison-Author of the first threading extensions to o Wayne Davison-Author of the first threading extensions to
the RN news reader (commonly called TRN). the RN news reader (commonly called TRN).
. Geoff Huston-Original author of ANU NEWS o Geoff Huston-Original author of ANU NEWS
. Phil Lapsey-Original author of the UNIX reference o Phil Lapsey-Original author of the UNIX reference
implementation for NNTP implementation for NNTP
. Iain Lea-Original maintainer of the TIN news reader o Iain Lea-Original maintainer of the TIN news reader
. Chris Lewis-First known implementer of the AUTHINFO o Chris Lewis-First known implementer of the AUTHINFO GENERIC
GENERIC extension
. Rich Salz-Original author of INN Barber Page [41]
. Henry Spencer-One of the original authors of CNEWS
. Kim Storm-Original author of the NN news reader INTERNET DRAFT S. Barber
Expires: May 15, 2002 Academ Consulting Services
extension
o Rich Salz-Original author of INN
o Henry Spencer-One of the original authors of CNEWS
o Kim Storm-Original author of the NN news reader
18. Author's Address 18. Author's Address
Stan Barber Stan Barber
P.O. Box 300481 P.O. Box 300481
Houston, Texas 77230 Houston, Texas 77230
Email: sob@academ.com Email: sob@academ.com
This document expires October 30, 2001. This document expires May 15, 2002.
Barber [Page 61] Barber Page [42]
 End of changes. 

This html diff was produced by rfcdiff 1.23, available from http://www.levkowetz.com/ietf/tools/rfcdiff/