draft-ietf-simple-pres-filter-reqs-01.txt   draft-ietf-simple-pres-filter-reqs-02.txt 
SIMPLE WG T. Moran SIMPLE WG H. Khartabil
Internet-Draft Internet-Draft E. Leppanen
Expires: December 17, 2003 S. Addagatla Expires: February 12, 2004 Nokia
E. Leppanen T. Moran
Nokia August 14, 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-01 draft-ietf-simple-pres-filter-reqs-02
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.
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This Internet-Draft will expire on December 17, 2003. This Internet-Draft will expire on February 12, 2004.
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 information 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. Overview of functionality . . . . . . . . . . . . . . . . . 4 3. Requirements for Specification of Filters . . . . . . . . . 4
4. Requirements for Specification of Filters . . . . . . . . . 4 3.1 Package Identification . . . . . . . . . . . . . . . . . . . 4
4.1 Common Syntax . . . . . . . . . . . . . . . . . . . . . . . 4 3.2 Target URI . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.2 Package Identification . . . . . . . . . . . . . . . . . . . 4 3.3 Notification Triggering . . . . . . . . . . . . . . . . . . 4
4.3 Target URI . . . . . . . . . . . . . . . . . . . . . . . . . 4 3.4 Notification Content . . . . . . . . . . . . . . . . . . . . 5
4.4 Notification Triggering . . . . . . . . . . . . . . . . . . 4 4. Requirements for Uploading Filter Criteria (Operational
4.5 Notification Content Limiting . . . . . . . . . . . . . . . 5 Rules) . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.6 Discovery of Items . . . . . . . . . . . . . . . . . . . . . 5 4.1 Subscription . . . . . . . . . . . . . . . . . . . . . . . . 5
5. Requirements for Uploading Filter Criteria (Operational 4.1.1 Maintaining a Filter . . . . . . . . . . . . . . . . . . . . 5
Rules) . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4.1.2 Changing a Filter . . . . . . . . . . . . . . . . . . . . . 6
5.1 SUBSCRIBE Method . . . . . . . . . . . . . . . . . . . . . . 6 4.2 Server Support For Filters . . . . . . . . . . . . . . . . . 6
5.1.1 Retention of Filter Criteria . . . . . . . . . . . . . . . . 6 5. Interaction with Other Features . . . . . . . . . . . . . . 6
5.1.2 Changing Filter Criteria . . . . . . . . . . . . . . . . . . 6 5.1 Resource Lists . . . . . . . . . . . . . . . . . . . . . . . 6
5.2 Server does not Support Filters . . . . . . . . . . . . . . 6 5.2 Partial Notifications . . . . . . . . . . . . . . . . . . . 7
5.3 Server does not Support Filter Criteria . . . . . . . . . . 6 5.3 Authorization . . . . . . . . . . . . . . . . . . . . . . . 7
5.4 Server can no Longer Support Filter Criteria . . . . . . . . 7 6. Security Considerations . . . . . . . . . . . . . . . . . . 7
6. Interaction with Other Features . . . . . . . . . . . . . . 7 7. Example Applications for Notification Filtering . . . . . . 8
6.1 Resource Lists . . . . . . . . . . . . . . . . . . . . . . . 7 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 8
6.2 Partial Notifications . . . . . . . . . . . . . . . . . . . 7 9. Main changes from version 01 . . . . . . . . . . . . . . . . 8
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 10. Main changes from version 00 . . . . . . . . . . . . . . . . 9
References . . . . . . . . . . . . . . . . . . . . . . . . . 9 References . . . . . . . . . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 10 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 10
Intellectual Property and Copyright Statements . . . . . . . 12 Intellectual Property and Copyright Statements . . . . . . . 11
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
describing the availability and willingness of the user (presentity) describing the availability and willingness of the user (presentity)
for communication. The user makes his presence information available for communication. The user makes his presence information available
for other users (watchers). for other users (watchers).
As the inherent usage of event packages grows, the client needs some As the inherent usage of event packages grows, the client needs some
mechanisms for controlling the event notifications at the source. mechanisms for controlling the event notifications at the source.
Evidence of this need is found in [4]. Evidence of this need is found in [4].
The Internet Draft describing the Presence event package [5] mentions The document describing the Presence event package [5] mentions the
the possibility for a filtering. Accordingly, the SUBSCRIBE request possibility for filtering. Accordingly, the SUBSCRIBE request may
may contain a body for filtering the presence information contain a body for filtering the presence information subscription.
subscription. However, the definition of the filtering has been left However, the definition of filtering was considered out of scope was
out of the scope of the Internet Draft. As an example, the body of left as future work.
the SUBSCRIBE request may include a restriction on the set of data
returned in NOTIFY requests.
These mechanisms are expected to be particularly valuable to users of These mechanisms are expected to be particularly valuable to users of
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 notifications.
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 4 and Section 5 of this draft propose a set of requirements Section 3 and Section 4 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 8 provides a few example applications of notification server. Section 7 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. Overview of functionality 3. Requirements for Specification of Filters
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.
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. The following requirements relate to the creation of filter criteria.
4.1 Common Syntax 3.1 Package Identification
A common set of constructs MUST be defined for the creation of rules. REQ xx: It MUST be possible for the creator of the filter to specify
There MUST be a common set of operations that follow a common syntax. the package the filter applies to.
The user MUST be possible to define different rules for different
purposes using a common filtering mechanism.
4.2 Package Identification 3.2 Target URI
A means is REQUIRED whereby the user may specify the package the REQ xx: It MUST be possible for the watcher to indicate, in the
rules apply to. filter, the target presentity whose presence information a certain
filter is applied to.
4.3 Target URI REQ xx: It MUST be possible for the watcher to indicate, in the
filter criteria, the target presentity list whose presence
information a certain filter is applied to.
It MUST be possible for the watcher in the filter criteria to REQ xx: It MUST be possible for the watcher to indicate, in the
indicate the target presentity, resource list or sub list of the filter criteria, the target presentity sub-list whose presence
resource list to which a certain filter criteria is applied if this information a certain filter is applied to.
is different from the Request-URI in the subscription.
4.4 Notification Triggering REQ xx: It MUST be possible for the watcher to indicate, in the
filter criteria, the target domain that contains presentities whose
presence information a certain filter is applied to.
This chapter presents requirements for specifying the desired 3.3 Notification Triggering
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 This chapter presents requirements for specifying the triggering
to specify such rules for the notification triggering where the conditions that result in notifications to be sent to the client.
criteria is based on the presence information, e.g., the value of the
status element.
The notification triggering criteria would override the default REQ xx: It MUST NOT be possible to break any server side policy
trigger conditions of the server/service as defined in the package constraints when applying the triggering conditions. For example, it
when they are within the server's local policy constraints. must not be possible for a watcher to request a notification when the
<status> element value of a certain presentity has changed from OPEN
to CLOSED when there is a local server policy constraining the
delivery of any tuple with a <status> element value of CLOSED.
It MUST be possible to specify logical expressions based on the value REQ xx: The triggering conditions MUST be based on the presence
of elements defined in the package for the purpose of when to send information. For example, the change of value of the <status>
notifications. This covers expressions (tests) related to the change element.
of an element's value, and reaching a certain value of an element.
It MUST be possible to construct expressions that combine multiple REQ xx: It MUST be possible to specify logical expressions based on
tests. the value of elements defined in the package for the purpose of
triggering. This covers expressions (tests) related to the change of
an element's value, and reaching a certain value of an element.
4.5 Notification Content Limiting REQ xx: It MUST be possible to construct one filter that combine
multiple triggering conditions.
This chapter presents requirements for specifying the content to be 3.4 Notification Content
sent in the notifications.
It MUST be possible for the watcher to specify the presence This chapter presents requirements for specifying the filter for
information elements [2] (XML elements and/or attributes) to be choosing content to be sent in the notifications.
delivered in the notification. The specified elements MUST be
possible to cover also extensions to PIDF formated presence
information, see for example [3].
E.g. the following two cases must be possible: REQ xx: It MUST NOT be possible to break any server side policy
constraints when applying the content filter. For example, it must
not be possible for a watcher to request a notification to contain
the <contact> element of a certain presentity when there is a local
server policy constraining the delivery of the <contact> element.
o It MUST be possible for the watcher to define a criteria which REQ xx: It MUST be possible for the watcher to specify the presence
allows the complete tuple and all information within a tuple to be information elements (XML elements and/or attributes) in [2] to be
transmitted. delivered in the notification.
o It MUST be possible for the watcher to define a criteria which REQ xx: It MUST be possible for the watcher to specify presence
result notifies to contain values only for defined attributes. information in any extension to PIDF to be delivered in the
notifications, based on XML elements and/or attributes. See for
example [3].
It MUST be possible to specify logical expressions based on the value REQ xx: It MUST be possible for the watcher to specify presence
of elements defined in the package for the purpose of determining information in any extension to be delivered in the notifications,
what to send in the notification. The existence of an element SHOULD based on namespaces.
be considered as a criterion.
It MUST be possible to construct expressions that combine multiple REQ xx: It MUST be possible to construct one filter that combine
tests. multiple elements and attributes to be included the notifications.
4.6 Discovery of Items 4. Requirements for Uploading Filter Criteria (Operational Rules)
It MUST be possible for the watcher to request to learn new items of REQ xx: It MUST be possible for the watcher to upload filter criteria
the presence information that the notifier may make available to the to the server (notifier) and know the status - accepted or rejected.
watcher. E.g., to discover additions of new tuples and/or other new
presence information items.
It MUST be possible for the watcher using the filter criteria to 4.1 Subscription
determine what presence information is available before subscribing
to presence information with the actual values.
5. Requirements for Uploading Filter Criteria (Operational Rules) REQ xx: It MUST be possible to place a filter in the body of the
SUBSCRIBE request.
It MUST be possible for the watcher to upload filter criteria to the REQ xx: It MAY be possible to deliver a filter to a server using
server (notifier) and know the status - accepted or rejected. other means. For example, it may be possible for the filter to be
(permanently) stored in the server.
5.1 SUBSCRIBE Method 4.1.1 Maintaining a Filter
Placing filter criteria in the body of the subscription MUST be REQ xx: The watcher MUST NOT be required to re-set a filter at any
supported. Other means of delivering the filter criteria to the time during the subscription, once the filter has been set.
server MAY be supported. E.g. it should be possible for the rules to
be (permanently) stored in the server, as in a resource list case.
5.1.1 Retention of Filter Criteria REQ xx: The watcher SHOULD NOT be required to re-set a filter when
refreshing a subscription, once the filter has been set.
The server MUST retain the filter criteria through the lifetime of REQ xx: Maintaining a filter across subscription refreshes SHOULD be
the subscription dialog until there is a modification to the filter bandwidth efficient.
settings.
5.1.2 Changing Filter Criteria 4.1.2 Changing a Filter
It MUST be possible to change the filter settings during a REQ xx: It MUST be possible to change the filter during a
subscription. subscription.
It MUST be possible for the watcher to reset the filter settings to REQ xx: It MUST be possible for the watcher to remove a set filter,
the service (server) defined default. reverting back to a server defined default.
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 4.2 Server Support For Filters
MUST be possible to indicate so in a response.
5.3 Server does not Support Filter Criteria REQ xx: It MUST be possible for a server not supporting filtering to
inform the watcher of the failure.
It MUST be possible for the server to explicitly indicate that it REQ xx: It MUST be possible for a server not understanding a
does not support or understand the filter criteria. This indication filtering to inform the watcher of the failure.
MAY include a reason about the refusal of the subscription.
5.4 Server can no Longer Support Filter Criteria REQ xx: It MUST be possible for a server not accepting a filter to
inform the watcher of the reasons for not accepting the filter.
The server MUST be able to terminate the subscription if the any of REQ xx: It MUST be possible for a server to terminate a subscription
the active filters are no longer applicable due to a policy in the based on a filter becoming invalid due to sever local policy change.
server. (How do I word this in a requirement text?)
6. Interaction with Other Features 5. Interaction with Other Features
6.1 Resource Lists 5.1 Resource Lists
It MUST be possible to support filtering for subscriptions to REQ xx: It MUST be possible to support filtering for subscriptions to
resource lists [8]. resource lists [8].
It MUST be possible for a watcher to specify filter criteria for a REQ xx: It MUST be possible for a watcher to specify filter criteria
resource list and/or any nested sub list of the resource list. 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 REQ xx: It MUST be possible for a watcher to specify different filter
individual member of a resource list in a resource list subscription. for any individual member of a resource list in a resource list
subscription.
It MUST be possible for a watcher to specify different filter REQ xx: It MUST be possible for a watcher to specify different filter
criteria for individual members of any of nested sub lists of a criteria for individual members of any of nested sub lists of a
resource list in a resource list subscription. Any of the nested sub resource list in a resource list subscription. Any of the nested sub
lists may be located in a different domain from the parent list. lists may be located in a different domain from the parent list.
It MUST be possible for each watcher to define own filter criteria REQ xx: It MUST be possible for each watcher to define own filter
within resource list subscription if there are several simultaneous criteria within resource list subscription if there are several
watchers using the same list. simultaneous watchers using the same list.
6.2 Partial Notifications 5.2 Partial Notifications
It MUST be possible to use filtering along with the partial REQ xx: It MUST be possible to use filtering along with the partial
notification [9] within the same subscription. notification [9] within the same subscription.
6.3 Authorization 5.3 Authorization
Authorization SHOULD occur irrespective of the filtering. REQ xx: Authorization SHOULD occur irrespective of the filtering.
7. Security Considerations 6. Security Considerations
Security requirements specified for [5] also applies to the presence Security requirements specified for [5] also applies to the presence
filtering. Additional security considerations related to the presence filtering. Additional security considerations related to the presence
filtering are described as follows. filtering are described as follows.
The filter criteria should not be rejected based on the authorization REQ xx: It SHOULD be possible for the server to hide the fact that a
policy since this would enable the watcher by experimentation with filter was not acceptable.
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 REQ xx: The presence of filter criteria in the body in a SIP message
significant effect on the way in which the request is handled at a has a significant effect on the way in which the request is handled
server. As a result, it is especially important that messages at a server. As a result, it is especially important that messages
containing filter criteria are authenticated and authorized. containing filter criteria are authenticated and authorized.
Modification to the Filter Criteria by an intermediary could also REQ xx: Modification to the Filter Criteria by an intermediary could
result in the watcher either not receiving notifications of presence also result in the watcher either not receiving notifications of
information they are interested in or receiving a very large presence presence information they are interested in or receiving a very large
document. Therefore the filter criteria should be integrity protected presence document. Therefore the filter criteria SHOULD be integrity
between those nodes that are authorised to modify it (e.g., the protected between those nodes that are authorised to modify it (e.g.,
resource list servers). the resource list servers).
Processing of requests and looking up filter criteria requires some REQ xx: Processing of requests and looking up filter criteria
amount of computation. This enables a DoS attack whereby a user can requires some amount of computation. This enables a DoS attack
send requests with substantial numbers messages with large contents, whereby a user can send requests with substantial numbers messages
in the hopes of overloading the server. To prevent this the number of with large contents, in the hopes of overloading the server. To
filter criteria allowed in a request should be limited. prevent this the number of filter criteria allowed in a request
should be limited.
Requests containing filter criteria can reveal sensitive information REQ xx: Requests containing filter criteria can reveal sensitive
about a UA's capabilities. If this information is sensitive, it information about a UA's capabilities. If this information is
SHOULD be encrypted using methods that allow it to be read by those sensitive, it SHOULD be encrypted using methods that allow it to be
nodes that need to do so (e.g., the resource list servers). 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 REQ xx: The resource list servers SHOULD convey only those parts of
information targetted to the same destination as the fanned out filter information targeted to the same destination as the fanned out
individual subscriptions, if the filter information is conveyed individual subscriptions, if the filter information is conveyed
further within the subscription. further within the subscription.
8. Example Applications for Notification Filtering 7. 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 watcher 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.
6. A watcher is intrested in being notified when a presentity gains 6. A watcher is interested in being notified when a presentity gains
a new communication capability such as a new networked a new communication capability such as a new networked
multi-player game. multi-player game.
9. Acknowledgements 8. Acknowledgements
The authors would like to thank Hisham Khartabil, Mikko Lonnfors, The authors would like to thank Andrew Allen, Sreenivas Addagatla,
Juha Kalliokulju, Aki Niemi, Jose Costa-Requena and Markus Isomaki Mikko Lonnfors, Juha Kalliokulju, Aki Niemi, Jose Costa-Requena and
for their valuable input. Markus Isomaki for their valuable input.
9. Main changes from version 01
o "Overview of Operation" section removed .
o "Common Syntax" section removed.
o "Discovery of Items" section removed as agreed in IETF 57
o Added requirement about filtering using namespaces.
o Added requirement about filtering using domain name.
o Clarified and split larger requirements into smaller more concrete
requirements.
o Updated the Authors of this ID
10. Main changes from version 00 10. Main changes from version 00
o Overview of functionality chapter added. o Overview of functionality chapter added.
o More specific requirements for supporting filtering with the o More specific requirements for supporting filtering with the
resource lists, and nested lists. resource lists, and nested lists.
o Interaction with other features chapter added. o Interaction with other features chapter added.
skipping to change at page 10, line 18 skipping to change at page 10, line 11
[8] Rosenberg, J., "A Session Initiation Protocol (SIP) Event [8] Rosenberg, J., "A Session Initiation Protocol (SIP) Event
Notification Extension for Resource Lists", Notification Extension for Resource Lists",
draft-ietf-simple-event-list-03.txt, May 2003. draft-ietf-simple-event-list-03.txt, May 2003.
[9] Lonnfors, M., "Partial Notification of Presence Information", [9] Lonnfors, M., "Partial Notification of Presence Information",
draft-lonnfors-simple-partial-notify-01.txt, May 2003. draft-lonnfors-simple-partial-notify-01.txt, May 2003.
Authors' Addresses Authors' Addresses
Tim Moran Hisham Khartabil
2800 Britt Drive
Argyle, Texas 76226
USA
Phone: +1 972 849 8821
EMail: tl_moran@att.net
Sreenivas Addagatla
Nokia Nokia
6000 Connection Drive P.O BOX 321
Irving, Texas 75039 Helsinki
USA Finland
Phone: +1 972 374 1917 Phone: +358 7180 76161
EMail: sreenivas.addagatla@nokia.com EMail: hisham.khartabil@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 Tim Moran
Mundelein, Illinois 60060 2800 Britt Drive
Argyle, Texas 76226
USA USA
EMail: AndrewAllen007@aol.com Phone: +1 972 849 8821
EMail: tl_moran@att.net
Intellectual Property Statement Intellectual Property Statement
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IETF's procedures with respect to rights in standards-track and IETF's procedures with respect to rights in standards-track and
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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.
Acknowledgment Acknowledgement
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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