One document matched: draft-garcia-sipping-file-event-package-01.txt

Differences from draft-garcia-sipping-file-event-package-00.txt




SIPPING Working Group                                   M. Garcia-Martin
Internet-Draft                                    Nokia Siemens Networks
Intended status: Standards Track                          M. Matuszewski
Expires: May 19, 2008                                              Nokia
                                                       November 16, 2007


 A Session Initiation Protocol (SIP) Event Package and Data Format for
                            Describing Files
               draft-garcia-sipping-file-event-package-01

Status of this Memo

   By submitting this Internet-Draft, each author represents that any
   applicable patent or other IPR claims of which he or she is aware
   have been or will be disclosed, and any of which he or she becomes
   aware will be disclosed, in accordance with Section 6 of BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
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   This Internet-Draft will expire on May 19, 2008.

Copyright Notice

   Copyright (C) The IETF Trust (2007).

Abstract

   This document specifies the format and semantics associated to a
   'file' event package that allows SIP endpoints to publish the
   availability of files.  A file can be, for example, images, video
   files, audio files, etc.  The event package reuses the eXtended
   Mark-up Language (XML) 'file-metadata' document to provide file
   descriptions.  This event package also allows SIP endpoints to



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   subscribe to changes in the availability of files, or perform
   searches for the availability and location of a given file.  Support
   for partial notifications and publications is also accomplished by
   using XML patch operations.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  4
   3.  The 'file' Event Package . . . . . . . . . . . . . . . . . . .  4
     3.1.  Package Name . . . . . . . . . . . . . . . . . . . . . . .  4
     3.2.  Event Package Parameters . . . . . . . . . . . . . . . . .  5
     3.3.  SUBSCRIBE Bodies . . . . . . . . . . . . . . . . . . . . .  5
     3.4.  Subscription duration  . . . . . . . . . . . . . . . . . .  5
     3.5.  NOTIFY Bodies  . . . . . . . . . . . . . . . . . . . . . .  5
     3.6.  Notifier processing of SUBSCRIBE requests  . . . . . . . .  6
       3.6.1.  Authentication . . . . . . . . . . . . . . . . . . . .  6
       3.6.2.  Authorization  . . . . . . . . . . . . . . . . . . . .  7
     3.7.  Notifier Generation of NOTIFY Requests . . . . . . . . . .  7
     3.8.  Subscriber Processing of NOTIFY Requests . . . . . . . . .  8
     3.9.  Handling of Forked Requests  . . . . . . . . . . . . . . .  9
     3.10. Rate of Notifications  . . . . . . . . . . . . . . . . . .  9
     3.11. State Agents . . . . . . . . . . . . . . . . . . . . . . .  9
     3.12. Examples . . . . . . . . . . . . . . . . . . . . . . . . . 10
     3.13. Use of URIs to Retrieve State  . . . . . . . . . . . . . . 10
     3.14. PUBLISH bodies . . . . . . . . . . . . . . . . . . . . . . 10
     3.15. PUBLISH Response Bodies  . . . . . . . . . . . . . . . . . 11
     3.16. Multiple Sources for Event State . . . . . . . . . . . . . 11
     3.17. Event State Segmentation . . . . . . . . . . . . . . . . . 11
     3.18. Rate of Publication  . . . . . . . . . . . . . . . . . . . 11
   4.  Security Considerations  . . . . . . . . . . . . . . . . . . . 12
   5.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 12
   6.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 12
     6.1.  Registration of the 'file' Event Package . . . . . . . . . 12
   7.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 12
     7.1.  Normative References . . . . . . . . . . . . . . . . . . . 12
     7.2.  Informative References . . . . . . . . . . . . . . . . . . 13
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 13
   Intellectual Property and Copyright Statements . . . . . . . . . . 15











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1.  Introduction

   There are scenarios where a SIP endpoint has a number of available
   files that can be offered for public disposal or for a limited number
   of authorized users.  One of these cases is, for example, when Alice
   takes some pictures with her camera phone and she wants to share them
   within a community.  This requires a mechanism that allows Alice to
   describe the files she wants to share.

   In another scenario, Alice might be interested in finding out the
   availability of a given file, defined by a set of parameters.  Think,
   for example, of Alice trying to find pictures of the bowling
   tournament that took place recently in her home town.  This implies a
   mechanism whereby Alice can perform searches of available files.  The
   user who performs the search identifies one or more aspects of the
   file she is searching, but probably she is not able to provide a full
   description of the file.

   SIP [RFC3261] provides an extensible event mechanism [RFC3265] that
   is suitable for our needs.  We enable the above scenarios by defining
   a SIP event package for file metadata publication and search.  We
   reuse the 'file-metadata' document format specified in the XML Data
   Format for describing files [I-D.garcia-app-area-file-data-format].
   All together, they allow an Event Publication Agent (EPA) to provide
   a description of locally available files in a PUBLISH request
   [RFC3903].  In a community, there can be an Event State Compositor
   that aggregates shared files available at different endpoints.  The
   Event State Compositor (ESC) that receives the PUBLISH request
   processes 'file-metadata' documents according to a well defined
   strategy (which is outside the scope of this document).  For example,
   the ESC can be a centralized intermediary facilitator for a given
   community, or it can be a super-node of a SIP Peer-to-Peer (P2P)
   network.

   A user that searches for one or more files issues a SUBSCRIBE request
   (either a subscription or a fetch of state, see RFC 3265 [RFC3265])
   to the 'file' event package.  Because a subscription to all of the
   files published in the community is likely to contain a large amount
   of data, the subscriber will typically attach a filter [RFC4661] that
   describes the files under search.  This will result in the generation
   of one or more NOTIFY requests that contains the searched items.
   Once the information on files is retrieved, the subscriber can use
   any suitable mechanism (such as the one defined in "Session
   Description Protocol (SDP) Offer/Answer Mechanism to Enable File
   Transfer" [I-D.ietf-mmusic-file-transfer-mech]) to actually download
   the file.  Such file transfer mechanisms are outside the scope of
   this memo.




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   In the file descriptor, sometimes the URI points to the file itself
   itself (such as an HTTP URI that points to an image file).  In other
   cases the URI merely resolves to a host where the content is
   available (for example, the SIP URI of a camera phone that stores
   images).


2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in BCP 14, RFC 2119
   [RFC2119] and indicate requirement levels for compliant
   implementations.


3.  The 'file' Event Package

   RFC 3265 [RFC3265] defines a SIP extension for subscribing to, and
   receiving notifications of changes (events) in the state of remote
   nodes.  It leaves the definition of many aspects of these events to
   concrete extensions, known as event packages.  This document
   qualifies as an event package.  This section fills in the information
   required for all event packages by RFC 3265 [RFC3265].

   Additionally, RFC 3903 [RFC3903] defines an extension that allows SIP
   User Agents to publish event state.  According to RFC 3903 [RFC3903]
   any event package intended to be used in conjunction with the SIP
   PUBLISH method has to include a considerations section.  This section
   also fills the information for all event packages to be used with
   PUBLISH requests.

   We define a new 'file' event package.  Event Publication Agents (EPA)
   use PUBLISH requests to inform an Event State Compositor (ESC) of
   changes in the 'file' event package.  The ESC, acting as a notifier,
   notifies subscribers to the 'file' event package when changes occur.

3.1.  Package Name

   The name of this package is 'file'.  As specified in RFC 3265
   [RFC3265], this value appears in the Event header field present in
   SUBSCRIBE and NOTIFY requests.  As specified in the RFC 3903
   [RFC3903], this value appears as well in the Event header field
   present in PUBLISH requests.







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3.2.  Event Package Parameters

   RFC 3265 [RFC3265] allows event packages to define additional
   parameters carried in the Event header field.  This event package,
   'file', does not define additional parameters.

3.3.  SUBSCRIBE Bodies

   According to RFC 3265 [RFC3265], a SUBSCRIBE request can contain a
   body.  The purpose of the body depends on its type.  Subscriptions to
   the 'file' event package MAY contain a filter body according to the
   format specified in [RFC4661].  Filters are used to reduce the number
   of results during searches.

3.4.  Subscription duration

   From the functional point of view, there are two kinds of
   subscriptions to the 'file' even package.  In one, the user may want
   to either perform a single search operation on the existing files.
   In the other, the user may want to monitor the changes in the state
   information of files.  These functionalities can be controlled by the
   duration of the subscription.

   A search on existing files can be implemented with a single fetch
   operation (where the Expires header field is set to zero) or by a
   subscription of a short duration (typically on the order of a few
   minutes).  The other functionality, where a user wants to monitor the
   changes of a state, is typically implemented as a lengthy
   subscription, on the order of hours, as the user needs to be notified
   whenever a change in the file has occurred.

   Due to the lack of congruence in the two types of subscriptions, it
   is hard to select a default expiration value.  We have decided to
   select a mean default value that accommodate both types of
   subscriptions: 1800 seconds.  As per RFC 3265 [RFC3265], the
   subscriber MAY specify an alternate expiration in the Expires header
   field.  It is RECOMMENDED that UACs always include an explicit
   Expires header field with the desired subscription value.

3.5.  NOTIFY Bodies

   As described in RFC 3265 [RFC3265], the NOTIFY message can contain a
   body describing the state of the subscribed resources.  This body is
   either in a format listed in the Accept header field of the SUBSCRIBE
   request, or in a package-specific default format, if the Accept
   header field was omitted from the SUBSCRIBE request.

   In this event package, the body of the notification contains a 'file-



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   metadata' document, specified in the XML Data Format for describing
   files [I-D.garcia-app-area-file-data-format].  A 'file-metadata'
   document can be expressed as a full or partial document.  An ESC can
   receive 'file-metadata' documents from different EPAs or other
   sources.  The ESC applies a composition policy, and composes a 'file-
   metadata' document that contains all the available known files to the
   EPA.  If the ESC is not able to resolve a conflict, due to
   contradictory information provided by two different EPAs, the ESC
   provides a comprehensive information for that file, so that the
   subscriber can resolve the conflict.

   All subscribers and notifiers of 'file' event package MUST support
   the "application/file+xml" data format described in XML Data Format
   for describing files [I-D.garcia-app-area-file-data-format].  The
   SUBSCRIBE request MAY contain an Accept header field.  If no such
   header field is present, it has a default value of "application/
   file+xml" (assuming that the Event header field contains a value of
   'file').  If the Accept header field is present, it MUST include
   "application/file+xml", and MAY include any other types capable of
   representing 'file-metadata' documents.

   When composing a 'file-metadata' document, the ESC MAY include
   several <instance> elements per <file> element.  This would be the
   case when the ESC has acquired information concerning the same file,
   for example, through publications from different EPAs.

3.6.  Notifier processing of SUBSCRIBE requests

   The contents of a 'file-metadata' document can contain sensitive
   information that can reveal some privacy information.  For example,
   it can contain a list of valuable files and the address (SIP URI) of
   the SIP User Agent where those are stored.  While this information
   itself is not very useful, it can be used by malicious agents, e.g.,
   to mount an attack to avoid other users to retrieve such a file.
   Therefore, 'file-metadata' documents MUST only be sent to authorized
   subscribers.  In order to determine if a subscription originates in
   an authorized user, the user MUST be authenticated as described in
   Section 3.6.1 and then he MUST be authorized to be a subscriber as
   described in Section 3.6.2.

3.6.1.  Authentication

   Notifiers SHOULD authenticate all subscription requests.  This
   authentication can be done using any of the mechanisms defined in RFC
   3261 [RFC3261] and other authentication extensions.






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3.6.2.  Authorization

   Once authenticated, the notifier makes an authorization decision.  A
   notifier MUST NOT accept a subscription unless authorization has been
   provided by the user.  The means by which authorization are provided
   are outside the scope of this document.  Authorization may have been
   provided ahead of time through access lists, perhaps specified in a
   web page, or provided with the Common Policy Framework [RFC4745].

3.7.  Notifier Generation of NOTIFY Requests

   RFC 3265 [RFC3265] details the formatting and structure of NOTIFY
   messages.  However, packages are mandated to provide detailed
   information on when to send a NOTIFY request, how to compute the
   state of the resource, how to generate neutral or fake state
   information, and whether state information is complete or partial.
   This section describes those details for the 'file' event package.

   A notifier MAY send a NOTIFY at any time.  The NOTIFY request MAY
   contain a body containing a 'file-metadata' document or any other
   type indicated by the subscriber in the Accept header field of the
   SUBSCRIBE request.  The times at which the NOTIFY is sent to a
   particular subscriber, and the contents of the body within that
   notification, are subject to any rules specified by the authorization
   policy that governs the subscription, but typically will contain an
   indication of those known files for which a change has occurred.

   Since 'file-metadata' documents can contain full or partial state,
   the first 'file-metadata' document that a notifier sends to
   subscriber MUST contain be a full 'file-metadata' document.
   Subsequent documents sent to the same subscriber MAY contain full
   'file-metadata' documents or partial 'file-metadata' documents (the
   XML Data Format for describing files
   [I-D.garcia-app-area-file-data-format] provides further discussion
   about full and partial 'file-metadata' documents).

   In the case of a pending subscription, when final authorization is
   determined, a NOTIFY request can be sent.  If the result of the
   authorization decision was success, a NOTIFY SHOULD be sent and
   SHOULD contain a full 'file-metadata' document with the current state
   of the files known by the notifier at that moment.  If the
   subscription is rejected, a NOTIFY MAY be sent.  As described in RFC
   3265 [RFC3265], the Subscription-State header field indicates the
   state of the subscription.

   Frequently, the notifier will have a incomplete view of the available
   files described in a 'file-metadata' document.  For the duration of
   the subscription, the notifier can be running searches for the



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   availability of the searched files.  When new state information is
   made available to the notifier, the notifier SHOULD provide this
   information to the subscribers, typically as notifications that
   contain a partial 'file-metadata' document.

   The body of the NOTIFY MUST be sent using one of the types listed in
   the Accept header field in the most recent SUBSCRIBE request, or
   using the type "application/file+xml" if no Accept header field was
   present.

   Notifiers will typically act as Event State Compositors (ESC) and
   thus, will learn the 'file' event state via PUBLISH requests sent
   from the user's Event Publication Agent (EPA) when the user makes one
   or more files available or via subscriptions passed further to other
   ESCs.

   For reasons of privacy, it will frequently be necessary to encrypt
   the contents of the notifications.  This can be accomplished using
   S/MIME [RFC3851].  The encryption can be performed using the key of
   the subscriber as identified in the From field of the SUBSCRIBE
   request.  Similarly, integrity of the notifications is important to
   subscribers.  As such, the contents of the notifications MAY provide
   authentication and message integrity using S/MIME [RFC3851].  This
   will require the notifier to sign the content of the notification
   with the notifier's private key.

3.8.  Subscriber Processing of NOTIFY Requests

   RFC 3265 [RFC3265] leaves it to event packages to describe the
   process followed by the subscriber upon receipt of a NOTIFY request,
   including any logic required to form a coherent resource state.

   In this specification, each NOTIFY request contains either no 'file-
   metadata' document, a full 'file-metadata' document representing
   files which are available at one or more SIP User Agents, or a
   partial 'file-metadata' document that represent changes with respect
   a previously notified 'file-metadata' document.  Within a dialog,
   when a 'file-metadata' document is received in a NOTIFY request with
   a higher CSeq header field value than a previously received NOTIFY,
   and when the 'version' attribute value of the <patch> element is
   increased by one it contains a partial 'file-metadata' document that
   updates a previously received 'file-metadata' document (see the XML
   Data Format for describing files
   [I-D.garcia-app-area-file-data-format] for more details).







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3.9.  Handling of Forked Requests

   RFC 3265 [RFC3265] requires each package to describe handling of
   forked SUBSCRIBE requests.

   This specification allows several dialogs to be constructed as a
   result of emitting an initial SUBSCRIBE request, i.e., in cases where
   the SUBSCRIBE request forked to several notifiers.  In this case, the
   subscriber will keep several simultaneous dialogs.  The subscriber
   SHOULD merge the several 'file-metadata' documents received in NOTIFY
   requests.  It might be possible that new <file> elements are received
   in forked 'file-metadata' documents, or it might be possible that
   existing <file> elements are updated with new information (e.g., a
   new <gruu> element).  In both cases the merge should provide a
   logical OR operation of all the available information such as new
   entries and added information to existing entries.

3.10.  Rate of Notifications

   RFC 3265 [RFC3265] requires each package to specify the maximum rate
   at which notifications can be sent.

   Notifiers of 'file-metadata' documents SHOULD NOT generate
   notifications for a single user at a higher rate than once every
   second.

3.11.  State Agents

   RFC 3265 [RFC3265] requires each package to consider the role of
   state agents in the package, and if they are used, to specify how
   authentication and authorization are done.

   This specification allows state agents to be located in the network.
   A given file might be available at different SIP User Agents in the
   network.  ESCs can act as state agents by compiling and aggregating
   state towards, e.g., subscribers, other networks or communities.
   State agents MUST use any of the mechanism specified in RFC 3261
   [RFC3261] or any other SIP extension to authenticate and authorize
   users prior to accepting publications.

   If the state agent acts as an aggregator, the state agent SHOULD
   aggregate all the information related to the same available file.  In
   this case, it is expected that, because the same file is available in
   different endpoints, there might be different URIs for a given
   available file.






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3.12.  Examples

   Examples of 'file-metadata' documents are provided in the XML Data
   Format for describing files [I-D.garcia-app-area-file-data-format].

3.13.  Use of URIs to Retrieve State

   RFC 3265 [RFC3265] allows packages to use URIs to retrieve large
   state documents.

   A 'file-metadata' document can be of any arbitrary length, and can
   also become too large to be reasonably sent in a SIP request.  To
   avoid the burden of transmitting large documents through SIP proxies
   and to avoid potential congestion scenarios, it is possible that the
   notifier instead includes a URI that points to the contents, rather
   than the actual contents.  For example, the notifier can include an
   HTTP [RFC2616] URI that points to the notifier itself.  Since HTTP
   requests are transferred via a congestion controlled protocol (such
   as TCP [RFC0793]), the inclusion of a URI to retrieve state mitigates
   the problem of large 'file-metadata' documents.

3.14.  PUBLISH bodies

   RFC 3903 [RFC3903] requires event packages to define the content
   types expected in PUBLISH requests.

   In this event package, the body of a PUBLISH request contains a
   'file-metadata' document (see the XML Data Format for describing
   files [I-D.garcia-app-area-file-data-format]).  This 'file-metadata'
   document describes the availability of one or more files (typically,
   but not necessarily, stored at the EPA).  EPAs SHOULD only publish
   the description of locally available files, i.e., the URI of the file
   SHOULD resolve to the EPA itself.

   All EPAs and ESCs MUST support the "application/file+xml" data format
   described in the XML Data Format for describing files
   [I-D.garcia-app-area-file-data-format]. and MAY support other
   formats.

   When the EPA is composing a 'file-metadata' document, the EPA SHOULD
   include only one <instance> element per <file> element, and the data
   SHOULD include only the local description of the file.

      Allowing EPAs to provide a description of non-locally stored files
      could be maliciously used for creating, e.g., denial of service
      attacks.

   EPAs MUST NOT publish non-local URIs in the <uri> element, although



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   they MAY publish several URIs for a single file, e.g., if the file is
   available through several protocols and URIs.

   EPAs MUST NOT include <user-aor> containing addresses-of-record that
   point to other users than the one whose file EPA is publishing.  ESCs
   MUST verify that a <user-aor> element received in a PUBLISH request
   belongs to the same user who published the request; this requires the
   ESC to first authenticate the publisher.

3.15.  PUBLISH Response Bodies

   This specification does not associate semantics to a body in a
   PUBLISH response.

3.16.  Multiple Sources for Event State

   RFC 3903 [RFC3903] requires event packages to specify whether
   multiple sources can contribute to the event state view at the ESC.

   This event package allows different EPAs to publish the availability
   of the same file.  For the same file, each EPA publishes data that is
   invariant with the instance of the file, and data that is specific
   with each instance.  The ESC SHOULD merge the data pertaining to the
   same file according to a composition policy.  This policy can, e.g.,
   list all the difference instances where each file is available.

3.17.  Event State Segmentation

   RFC 3903 [RFC3903] defines segments within a state document.  Each
   segment is defined as one of potentially many identifiable sections
   in the published event state.

   In this 'file' event package, each <file> element composes a segment.

3.18.  Rate of Publication

   RFC 3903 [RFC3903] allows event packages to define their own rate of
   publication.

   There are no rate limiting recommendations for 'file' publication.
   It is expected that new files are added at the time of creation
   (e.g., a new image is taken with a camera phone), and that they are
   not changed often.  Thus, a typical rate of publication does not
   exist and there is no foreseen need to limit the rate of
   publications.






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4.  Security Considerations

   TBD


5.  Acknowledgements

   The authors would like to thank Nicklas Beijar and Juuso Lehtinen
   held fruitful discussions with the authors that lead to the design of
   this event package.  Pekka Kuure and Arto Leppisaari provided helpful
   comments during the initial review.


6.  IANA Considerations

6.1.  Registration of the 'file' Event Package

   This specification registers an event package, based on the
   registration procedures defined in RFC 3265 [RFC3265].  The following
   is the information required for such a registration:

      Package Name: file

      Package or Template-Package: This is a package.

      Published Document: RFC XXX [Replace by the RFC number of this
      specification].

      Person to Contact: Miguel A. Garcia-Martin, miguel.garcia@nsn.com


7.  References

7.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC3261]  Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston,
              A., Peterson, J., Sparks, R., Handley, M., and E.
              Schooler, "SIP: Session Initiation Protocol", RFC 3261,
              June 2002.

   [RFC3265]  Roach, A., "Session Initiation Protocol (SIP)-Specific
              Event Notification", RFC 3265, June 2002.

   [RFC3851]  Ramsdell, B., "Secure/Multipurpose Internet Mail
              Extensions (S/MIME) Version 3.1 Message Specification",



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              RFC 3851, July 2004.

   [RFC3903]  Niemi, A., "Session Initiation Protocol (SIP) Extension
              for Event State Publication", RFC 3903, October 2004.

   [I-D.garcia-app-area-file-data-format]
              Garcia-Martin, M. and M. Matuszewski, "An Extensible Data
              Format (XML) for Describing Files",
              draft-garcia-app-area-file-data-format-00 (work in
              progress), November 2007.

7.2.  Informative References

   [I-D.ietf-mmusic-file-transfer-mech]
              Garcia-Martin, M., Isomaki, M., Camarillo, G., and S.
              Loreto, "A Session Description Protocol (SDP) Offer/Answer
              Mechanism to Enable File  Transfer",
              draft-ietf-mmusic-file-transfer-mech-04 (work in
              progress), October 2007.

   [RFC0793]  Postel, J., "Transmission Control Protocol", STD 7,
              RFC 793, September 1981.

   [RFC2616]  Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
              Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
              Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.

   [RFC4661]  Khartabil, H., Leppanen, E., Lonnfors, M., and J. Costa-
              Requena, "An Extensible Markup Language (XML)-Based Format
              for Event Notification Filtering", RFC 4661,
              September 2006.

   [RFC4745]  Schulzrinne, H., Tschofenig, H., Morris, J., Cuellar, J.,
              Polk, J., and J. Rosenberg, "Common Policy: A Document
              Format for Expressing Privacy Preferences", RFC 4745,
              February 2007.


Authors' Addresses

   Miguel A. Garcia-Martin
   Nokia Siemens Networks
   P.O.Box 6
   Nokia Siemens Networks, FIN  02022
   Finland

   Email: miguel.garcia@nsn.com




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   Marcin Matuszewski
   Nokia
   P.O.Box 407
   NOKIA GROUP, FIN  00045
   Finland

   Email: marcin.matuszewski@nokia.com












































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PAFTECH AB 2003-20262026-04-23 06:09:56