draft-ietf-simple-pres-filter-reqs-00.txt   draft-ietf-simple-pres-filter-reqs-01.txt 
SIMPLE WG T. Moran SIMPLE WG T. Moran
Internet-Draft Internet-Draft
Expires: November 9, 2003 S. Addagatla Expires: December 17, 2003 S. Addagatla
E. Leppanen E. Leppanen
Nokia Nokia
May 11, 2003 A. Allen
June 18, 2003
Requirements for Presence Specific Event Notification Filtering Requirements for Presence Specific Event Notification Filtering
draft-ietf-simple-pres-filter-reqs-00 draft-ietf-simple-pres-filter-reqs-01
Status of this Memo Status of this Memo
This document is an Internet-Draft and is in full conformance with This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026. all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that other Task Force (IETF), its areas, and its working groups. Note that other
groups may also distribute working documents as Internet-Drafts. groups may also distribute working documents as Internet-Drafts.
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and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at http:// The list of current Internet-Drafts can be accessed at http://
www.ietf.org/ietf/1id-abstracts.txt. www.ietf.org/ietf/1id-abstracts.txt.
The list of Internet-Draft Shadow Directories can be accessed at The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html. http://www.ietf.org/shadow.html.
This Internet-Draft will expire on November 9, 2003. This Internet-Draft will expire on December 17, 2003.
Copyright Notice Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved. Copyright (C) The Internet Society (2003). All Rights Reserved.
Abstract Abstract
This document defines a set of structured requirements whereby a This document defines a set of structured requirements whereby a
presence information subscriber may select specific information to be presence information subscriber may select specific information to be
received in the presence infomation notification sent by the received in the presence infomation notification sent by the
notifier. The purpose is to limit the content and frequency of notifier. The purpose is to limit the content and frequency of
notifications so that only essential information on a need basis is notifications so that only essential information on a need basis is
delivered by the server. delivered by the server.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Requirements for Specification of Filters . . . . . . . . . 4 3. Overview of functionality . . . . . . . . . . . . . . . . . 4
3.1 Common Syntax . . . . . . . . . . . . . . . . . . . . . . . 4 4. Requirements for Specification of Filters . . . . . . . . . 4
3.2 Package Identification . . . . . . . . . . . . . . . . . . . 4 4.1 Common Syntax . . . . . . . . . . . . . . . . . . . . . . . 4
3.3 Target URI . . . . . . . . . . . . . . . . . . . . . . . . . 4 4.2 Package Identification . . . . . . . . . . . . . . . . . . . 4
3.4 Notification Triggering . . . . . . . . . . . . . . . . . . 4 4.3 Target URI . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.5 Notification Content Limiting . . . . . . . . . . . . . . . 5 4.4 Notification Triggering . . . . . . . . . . . . . . . . . . 4
4. Requirements for Uploading Rules (Operational Rules) . . . . 5 4.5 Notification Content Limiting . . . . . . . . . . . . . . . 5
4.1 SUBSCRIBE Method . . . . . . . . . . . . . . . . . . . . . . 5 4.6 Discovery of Items . . . . . . . . . . . . . . . . . . . . . 5
4.1.1 Retention of Filter Settings . . . . . . . . . . . . . . . . 5 5. Requirements for Uploading Filter Criteria (Operational
4.1.2 Changing Filter Settings . . . . . . . . . . . . . . . . . . 6 Rules) . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.2 Server does not Support Filters . . . . . . . . . . . . . . 6 5.1 SUBSCRIBE Method . . . . . . . . . . . . . . . . . . . . . . 6
4.3 Server does not Support Filter Settings . . . . . . . . . . 6 5.1.1 Retention of Filter Criteria . . . . . . . . . . . . . . . . 6
4.4 Server can no Longer Support Filter Settings . . . . . . . . 6 5.1.2 Changing Filter Criteria . . . . . . . . . . . . . . . . . . 6
5. Security Considerations . . . . . . . . . . . . . . . . . . 6 5.2 Server does not Support Filters . . . . . . . . . . . . . . 6
6. Example Applications for Notification Filtering . . . . . . 6 5.3 Server does not Support Filter Criteria . . . . . . . . . . 6
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 7 5.4 Server can no Longer Support Filter Criteria . . . . . . . . 7
References . . . . . . . . . . . . . . . . . . . . . . . . . 7 6. Interaction with Other Features . . . . . . . . . . . . . . 7
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 7 6.1 Resource Lists . . . . . . . . . . . . . . . . . . . . . . . 7
Intellectual Property and Copyright Statements . . . . . . . 9 6.2 Partial Notifications . . . . . . . . . . . . . . . . . . . 7
6.3 Authorization . . . . . . . . . . . . . . . . . . . . . . . 7
7. Security Considerations . . . . . . . . . . . . . . . . . . 7
8. Example Applications for Notification Filtering . . . . . . 8
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 9
10. Main changes from version 00 . . . . . . . . . . . . . . . . 9
References . . . . . . . . . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 10
Intellectual Property and Copyright Statements . . . . . . . 12
1. Introduction 1. Introduction
SIP event notification is described in [6]. It defines a general SIP event notification is described in [6]. It defines a general
framework for subscriptions and notifications for SIP event packages. framework for subscriptions and notifications for SIP event packages.
Concrete applications of the general event framework to a specific Concrete applications of the general event framework to a specific
group of events are described in [5] (user presence) and [7] (watcher group of events are described in [5] (user presence) and [7] (watcher
information). information).
The presence information refers to a set of presence attributes The presence information refers to a set of presence attributes
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wireless devices. The characteristics of these devices typically wireless devices. The characteristics of these devices typically
include low bandwidth, low data processing capabilities, small include low bandwidth, low data processing capabilities, small
display and limited battery power. Such devices can benefit from the display and limited battery power. Such devices can benefit from the
ability to filter the amount of information generated at the source ability to filter the amount of information generated at the source
of the event notification. of the event notification.
However, it is expected that the control mechanisms for event However, it is expected that the control mechanisms for event
notifications add value for all users irrespectively of their device notifications add value for all users irrespectively of their device
or network access characteristics. or network access characteristics.
Section 3 and Section 4 of this draft propose a set of requirements Section 4 and Section 5 of this draft propose a set of requirements
whereby a client may specify which notifications it is interested in. whereby a client may specify which notifications it is interested in.
That is, a means to specify filtering rules to be executed by the That is, a means to specify filtering rules to be executed by the
server. Section 6 provides a few example applications of notification server. Section 8 provides a few example applications of notification
filtering. filtering.
2. Conventions 2. Conventions
In this document, the key words 'MUST', 'MUST NOT', 'REQUIRED', In this document, the key words 'MUST', 'MUST NOT', 'REQUIRED',
'SHALL', 'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'MAY', 'SHALL', 'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'MAY',
and 'OPTIONAL' are to be interpreted as described in RFC 2119 [1] and 'OPTIONAL' are to be interpreted as described in RFC 2119 [1]
and indicate requirement levels for compliant implementations. and indicate requirement levels for compliant implementations.
3. Requirements for Specification of Filters 3. Overview of functionality
The following requirements relate to the creation of filters (rules). Filter Criteria set by a watcher may be set based on some
predetermined knowledge of the structure of the presence information,
or the filtering mechanism may itself be used to first discover the
structure of the presence information thus enabling the setting new
filter criteria to deliver the values of interest.
3.1 Common Syntax The filtering may be performed either by the presence server of the
presentity (the notifier) or by some intermediate server between the
notifier and the watcher. The filtering should be considered as a
post processing operation on the presence document after it has been
modified due the rules of the authorization. As a result the
authorization policy always overides any of the data or notifications
requested by any of the filter criteria.
Subscriptions containing filter criteria may either be accepted or
rejected by the notifier based on the presence of filter criteria.
4. Requirements for Specification of Filters
The following requirements relate to the creation of filter criteria.
4.1 Common Syntax
A common set of constructs MUST be defined for the creation of rules. A common set of constructs MUST be defined for the creation of rules.
There MUST be a common set of operations that follow a common syntax. There MUST be a common set of operations that follow a common syntax.
The user MUST be possible to define different rules for different The user MUST be possible to define different rules for different
purposes using a common filtering mechanism. purposes using a common filtering mechanism.
3.2 Package Identification 4.2 Package Identification
A means is REQUIRED whereby the user may specify the package the A means is REQUIRED whereby the user may specify the package the
rules apply to. rules apply to.
3.3 Target URI 4.3 Target URI
It MUST be possible for the watcher to indicate the target presentity
or presentity list to which a certain filter criteria is applied.
It MUST be possible to support filtering also in presence list
subscriptions.
Is MUST be possible to specify different filter criteria for It MUST be possible for the watcher in the filter criteria to
individual presentities than the other presence list members in a indicate the target presentity, resource list or sub list of the
presence list subscription case. resource list to which a certain filter criteria is applied if this
is different from the Request-URI in the subscription.
3.4 Notification Triggering 4.4 Notification Triggering
This chapter presents requirements for specifying the desired This chapter presents requirements for specifying the desired
conditions for when notifications are to be sent to the client. conditions for when notifications are to be sent to the client.
The scope of the 'when' part is to allow a possibility for the user The scope of the 'when' part is to allow a possibility for the user
to specify such rules for the notification triggering where the to specify such rules for the notification triggering where the
criteria is based on the presence information, e.g., the value of the criteria is based on the presence information, e.g., the value of the
status element. status element.
The notification triggering criteria would override the default The notification triggering criteria would override the default
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when they are within the server's local policy constraints. when they are within the server's local policy constraints.
It MUST be possible to specify logical expressions based on the value It MUST be possible to specify logical expressions based on the value
of elements defined in the package for the purpose of when to send of elements defined in the package for the purpose of when to send
notifications. This covers expressions (tests) related to the change notifications. This covers expressions (tests) related to the change
of an element's value, and reaching a certain value of an element. of an element's value, and reaching a certain value of an element.
It MUST be possible to construct expressions that combine multiple It MUST be possible to construct expressions that combine multiple
tests. tests.
3.5 Notification Content Limiting 4.5 Notification Content Limiting
This chapter presents requirements for specifying the content to be This chapter presents requirements for specifying the content to be
sent in the notifications. sent in the notifications.
It MUST be possible for the watcher to specify the presence It MUST be possible for the watcher to specify the presence
information elements [2] (XML elements and/or attributes) to be information elements [2] (XML elements and/or attributes) to be
delivered in the notification. The specified elements MUST be able to delivered in the notification. The specified elements MUST be
cover also extensions to PIDF formated presence information, see for possible to cover also extensions to PIDF formated presence
example [3]. information, see for example [3].
E.g. the following two cases must be possible: E.g. the following two cases must be possible:
o The watcher MUST be able to define a criteria which allows the o It MUST be possible for the watcher to define a criteria which
complete tuple and all information within a tuple to be allows the complete tuple and all information within a tuple to be
transmitted. transmitted.
o The watcher MUST be able to define a criteria which result o It MUST be possible for the watcher to define a criteria which
notifies to contain values only for defined attributes. result notifies to contain values only for defined attributes.
It MUST be possible to specify logical expressions based on the value It MUST be possible to specify logical expressions based on the value
of elements defined in the package for the purpose of determining of elements defined in the package for the purpose of determining
what to send in the notification. The existence of an element SHOULD what to send in the notification. The existence of an element SHOULD
be considered as a criterion. be considered as a criterion.
It MUST be possible to construct expressions that combine multiple It MUST be possible to construct expressions that combine multiple
tests. tests.
4. Requirements for Uploading Rules (Operational Rules) 4.6 Discovery of Items
It MUST be possible for the watcher to upload the rules to the server It MUST be possible for the watcher to request to learn new items of
(notifier) and know the status - accepted or rejected. the presence information that the notifier may make available to the
watcher. E.g., to discover additions of new tuples and/or other new
presence information items.
4.1 SUBSCRIBE Method It MUST be possible for the watcher using the filter criteria to
determine what presence information is available before subscribing
to presence information with the actual values.
Placing filtering rules in the body of the subscription MUST be 5. Requirements for Uploading Filter Criteria (Operational Rules)
supported. Other means of delivering the filtering rules to the event
It MUST be possible for the watcher to upload filter criteria to the
server (notifier) and know the status - accepted or rejected.
5.1 SUBSCRIBE Method
Placing filter criteria in the body of the subscription MUST be
supported. Other means of delivering the filter criteria to the
server MAY be supported. E.g. it should be possible for the rules to server MAY be supported. E.g. it should be possible for the rules to
be (permanently) stored in the server, as in a presence list case. be (permanently) stored in the server, as in a resource list case.
4.1.1 Retention of Filter Settings 5.1.1 Retention of Filter Criteria
The server MUST retain the uploaded filter setting for the duration The server MUST retain the filter criteria through the lifetime of
of the subscription. the subscription dialog until there is a modification to the filter
settings.
4.1.2 Changing Filter Settings 5.1.2 Changing Filter Criteria
It MUST be possible to change the filter settings during a It MUST be possible to change the filter settings during a
subscription. subscription.
It MUST be possible for the watcher to reset the filter settings to It MUST be possible for the watcher to reset the filter settings to
the service (server) defined default. the service (server) defined default.
4.2 Server does not Support Filters Changing filter criteria SHOULD be bandwidth efficient.
5.2 Server does not Support Filters
If the server does not support filters (the content type) then it If the server does not support filters (the content type) then it
MUST be able to indicate so in a response. MUST be possible to indicate so in a response.
4.3 Server does not Support Filter Settings 5.3 Server does not Support Filter Criteria
It MUST be possible for the server to explicitly indicate that it It MUST be possible for the server to explicitly indicate that it
does not support or understand the filter settings. This indication does not support or understand the filter criteria. This indication
MAY include a reason about the refusal of the filter settings. MAY include a reason about the refusal of the subscription.
4.4 Server can no Longer Support Filter Settings 5.4 Server can no Longer Support Filter Criteria
The server MUST be able to terminate the subscription if the active The server MUST be able to terminate the subscription if the any of
filter is no longer applicable due to a policy in the server. the active filters are no longer applicable due to a policy in the
server.
5. Security Considerations 6. Interaction with Other Features
Further security requirements over [5] have not yet been identified. 6.1 Resource Lists
6. Example Applications for Notification Filtering It MUST be possible to support filtering for subscriptions to
resource lists [8].
It MUST be possible for a watcher to specify filter criteria for a
resource list and/or any nested sub list of the resource list.
It MUST be possible for a watcher to specify different filter for any
individual member of a resource list in a resource list subscription.
It MUST be possible for a watcher to specify different filter
criteria for individual members of any of nested sub lists of a
resource list in a resource list subscription. Any of the nested sub
lists may be located in a different domain from the parent list.
It MUST be possible for each watcher to define own filter criteria
within resource list subscription if there are several simultaneous
watchers using the same list.
6.2 Partial Notifications
It MUST be possible to use filtering along with the partial
notification [9] within the same subscription.
6.3 Authorization
Authorization SHOULD occur irrespective of the filtering.
7. Security Considerations
Security requirements specified for [5] also applies to the presence
filtering. Additional security considerations related to the presence
filtering are described as follows.
The filter criteria should not be rejected based on the authorization
policy since this would enable the watcher by experimentation with
the use of filter criteria to determine the authorization policy the
presentity has set for him and thus discover what the presentity
wants to hide from him.
The presence of filter criteria in the body in a SIP message has a
significant effect on the way in which the request is handled at a
server. As a result, it is especially important that messages
containing filter criteria are authenticated and authorized.
Modification to the Filter Criteria by an intermediary could also
result in the watcher either not receiving notifications of presence
information they are interested in or receiving a very large presence
document. Therefore the filter criteria should be integrity protected
between those nodes that are authorised to modify it (e.g., the
resource list servers).
Processing of requests and looking up filter criteria requires some
amount of computation. This enables a DoS attack whereby a user can
send requests with substantial numbers messages with large contents,
in the hopes of overloading the server. To prevent this the number of
filter criteria allowed in a request should be limited.
Requests containing filter criteria can reveal sensitive information
about a UA's capabilities. If this information is sensitive, it
SHOULD be encrypted using methods that allow it to be read by those
nodes that need to do so (e.g., the resource list servers).
The resource list servers should convey only those parts of filter
information targetted to the same destination as the fanned out
individual subscriptions, if the filter information is conveyed
further within the subscription.
8. Example Applications for Notification Filtering
1. A watcher wishes to get to know presentity's availability and 1. A watcher wishes to get to know presentity's availability and
willingness for messaging (e.g. IM and MMS). willingness for messaging (e.g. IM and MMS).
2. A watcher is interested in getting information about the 2. A watcher is interested in getting information about the
communication means and contact addresses the presentity is communication means and contact addresses the presentity is
currently available for communication. currently available for communication.
3. A watcher requires a notification if the state of a buddy has 3. A watcher requires a notification if the state of a buddy has
changed to 'open'. changed to 'open'.
4. A Subscriber only wants to be notified when the presentity's 4. A Subscriber only wants to be notified when the presentity's
location is Dallas or Fort Worth. The notification should include location is Dallas or Fort Worth. The notification should include
the vehicle license, driver name, and city. the vehicle license, driver name, and city.
5. A Basic location tracking service requires notification when the 5. A Basic location tracking service requires notification when the
presentity's cell id changes. The notification should include the presentity's cell id changes. The notification should include the
cell id. cell id.
7. Acknowledgements 6. A watcher is intrested in being notified when a presentity gains
a new communication capability such as a new networked
multi-player game.
9. Acknowledgements
The authors would like to thank Hisham Khartabil, Mikko Lonnfors, The authors would like to thank Hisham Khartabil, Mikko Lonnfors,
Juha Kalliokulju, Aki Niemi, Jose Costa-Requena and Markus Isomaki Juha Kalliokulju, Aki Niemi, Jose Costa-Requena and Markus Isomaki
for their valuable input. for their valuable input.
10. Main changes from version 00
o Overview of functionality chapter added.
o More specific requirements for supporting filtering with the
resource lists, and nested lists.
o Interaction with other features chapter added.
o More specific requirements to support getting information about
the structure of presence document, and changes in it.
o Several filter specific additions to security considerations.
o Several editorial changes, e.g., reference and terminology
updates.
References References
[1] Bradner, S., "Key words for use in RFCs to Indicate Requirement [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997. Levels", BCP 14, RFC 2119, March 1997.
[2] Sugano, H., "CPIM Presence Information Data Format", [2] Sugano, H., "CPIM Presence Information Data Format",
draft-ietf-impp-cpim-pidf-07.txt, December 2002. draft-ietf-impp-cpim-pidf-08.txt, May 2003.
[3] Schulzrinne, H., "RPIDS -- Rich Presence Information Data Format [3] Schulzrinne, H., "RPIDS -- Rich Presence Information Data Format
for Presence Based on the Session Initiation Protocol (SIP)", for Presence Based on the Session Initiation Protocol (SIP)",
draft-schulzrinne-simple-rpids-01.txt, February 2003. draft-schulzrinne-simple-rpids-01.txt, February 2003.
[4] Kiss, K., "Requirements for Presence Service based on 3GPP [4] Kiss, K., "Requirements for Presence Service based on 3GPP
specifications and wireless environment characteristics", specifications and wireless environment characteristics",
draft-kiss-simple-presence-wireless-reqs-02, February 2003. draft-kiss-simple-presence-wireless-reqs-02, February 2003.
[5] Rosenberg, J., "Session Initiation Protocol (SIP) Extensions for [5] Rosenberg, J., "Session Initiation Protocol (SIP) Extensions for
Presence", draft-ietf-simple-presence-10.txt, January 2003. Presence", draft-ietf-simple-presence-10.txt, January 2003.
[6] Roach, A., "Session Initiation Protocol (SIP)-Specific Event [6] Roach, A., "Session Initiation Protocol (SIP)-Specific Event
Notification", RFC 3265, June 2002. Notification", RFC 3265, June 2002.
[7] Rosenberg, J., "A Watcher Information Event Template-Package for [7] Rosenberg, J., "A Watcher Information Event Template-Package for
the Session Initiation Protocol (SIP)", the Session Initiation Protocol (SIP)",
draft-ietf-simple-winfo-package-05.txt, January 2003. draft-ietf-simple-winfo-package-05.txt, January 2003.
[8] Rosenberg, J., "A Session Initiation Protocol (SIP) Event
Notification Extension for Resource Lists",
draft-ietf-simple-event-list-03.txt, May 2003.
[9] Lonnfors, M., "Partial Notification of Presence Information",
draft-lonnfors-simple-partial-notify-01.txt, May 2003.
Authors' Addresses Authors' Addresses
Tim Moran Tim Moran
2800 Britt Drive 2800 Britt Drive
Argyle, Texas 76226 Argyle, Texas 76226
USA USA
Phone: +1 972 849 8821 Phone: +1 972 849 8821
EMail: tl_moran@att.net EMail: tl_moran@att.net
Sreenivas Addagatla Sreenivas Addagatla
Nokia Nokia
6000 Connection Drive 6000 Connection Drive
Irving, Texas 75039 Irving, Texas 75039
USA USA
Phone: +1 972 374 1917 Phone: +1 972 374 1917
EMail: sreenivas.addagatla@nokia.com EMail: sreenivas.addagatla@nokia.com
Eva Leppanen Eva Leppanen
skipping to change at page 9, line 4 skipping to change at page 11, line 4
EMail: sreenivas.addagatla@nokia.com EMail: sreenivas.addagatla@nokia.com
Eva Leppanen Eva Leppanen
Nokia Nokia
P.O BOX 785 P.O BOX 785
Tampere Tampere
Finland Finland
Phone: +358 7180 77066 Phone: +358 7180 77066
EMail: eva-maria.leppanen@nokia.com EMail: eva-maria.leppanen@nokia.com
Andrew Allen
1937 McRae Lane
Mundelein, Illinois 60060
USA
EMail: AndrewAllen007@aol.com
Intellectual Property Statement Intellectual Property Statement
The IETF takes no position regarding the validity or scope of any The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to intellectual property or other rights that might be claimed to
pertain to the implementation or use of the technology described in pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights this document or the extent to which any license under such rights
might or might not be available; neither does it represent that it might or might not be available; neither does it represent that it
has made any effort to identify any such rights. Information on the has made any effort to identify any such rights. Information on the
IETF's procedures with respect to rights in standards-track and IETF's procedures with respect to rights in standards-track and
skipping to change at page 10, line 7 skipping to change at page 13, line 7
The limited permissions granted above are perpetual and will not be The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assignees. revoked by the Internet Society or its successors or assignees.
This document and the information contained herein is provided on an This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgement Acknowledgment
Funding for the RFC Editor function is currently provided by the Funding for the RFC Editor function is currently provided by the
Internet Society. Internet Society.
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