SIPREC                                           Ram Mohan. Ravindranath
Internet-Draft                                       Cisco Systems, Inc.
Intended status: Standards Track                Parthasarathi. Ravindran
Expires: April 25, 2013                           Nokia Siemens Networks
                                                           Paul. Kyzivat
                                                                  Huawei
                                                        October 22, 2012


         Session Initiation Protocol (SIP) Recording Call Flows
                     draft-ram-siprec-callflows-02

Abstract

   Session recording is a critical requirement in many communications
   environments such as call centers and financial trading.  In some of
   these environments, all calls must be recorded for regulatory,
   compliance, and consumer protection reasons.  Recording of a session
   is typically performed by sending a copy of a media stream to a
   recording device.  This document lists call flows that has snapshot
   of metadata sent from SRC to SRS, the metadata format for which is
   described in [I-D.ietf-siprec-metadata] .  This is purely an
   informational document that is written to support the model defined
   the metadata draft.

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on April 25, 2013.

Copyright Notice

   Copyright (c) 2012 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal



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   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
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   described in the Simplified BSD License.


Table of Contents

   1.  Overview . . . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  3
   3.  Metadata XML schema Instances  . . . . . . . . . . . . . . . .  3
     3.1.  Sample Call flow . . . . . . . . . . . . . . . . . . . . .  3
     3.2.  Example 1: Basic Call  . . . . . . . . . . . . . . . . . .  5
     3.3.  Example 2: Hold/resume . . . . . . . . . . . . . . . . . .  7
     3.4.  Example 3: Basic Call with transfer  . . . . . . . . . . . 10
     3.5.  Example 4: Call disconnect . . . . . . . . . . . . . . . . 14
     3.6.  Example 5: Multiple CS into single RS with mixed stream  . 15
   4.  Security Considerations  . . . . . . . . . . . . . . . . . . . 17
   5.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 17
   6.  Acknowledgement  . . . . . . . . . . . . . . . . . . . . . . . 17
   7.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 17
     7.1.  Normative References . . . . . . . . . . . . . . . . . . . 17
     7.2.  Informative References . . . . . . . . . . . . . . . . . . 17
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 17























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1.  Overview

   [I-D.ietf-siprec-metadata] document focuses on the Recording metadata
   which describes the communication session.  The document lists a few
   examples and shows the snapshots of metadata sent from SRC to SRS.
   For the sake of simplicity the entire SIP [RFC3261] messages are not
   shown at various points, instead only a snip of the SIP/SDP message
   and the XML snapshot of metadata is shown.  This document is
   informational and is not normative on any aspect of SIP.


2.  Terminology

   The terms using in this defined are defined in
   [I-D.ietf-siprec-metadata].  No new terms/definitions are introduced
   in this document.


3.  Metadata XML schema Instances

   This section describes the metadata model XML instances for different
   use cases of SIPREC.  For the sake of simplicity the complete SIP
   messages are NOT shown here.

3.1.  Sample Call flow

   The following is a sample call flow that shows the SRC establishing a
   recording session towards the SRS.  The call flow is essentially
   identical when the SRC is a B2BUA or as the endpoint itself.  Note
   that the SRC can choose when to establish the Recording Session
   independent of the Communication Session, even though the following
   call flow suggests that the SRC is establishing the Recording Session
   (message #5) after the Communication Session is established.


















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         UA A           SRC                    UA B                  SRS
         |(1)CS INVITE  |                       |                      |
         |------------->|                       |                      |
         |              |(2)CS INVITE           |                      |
         |              |---------------------->|                      |
         |              |           (3) 200 OK  |                      |
         |              |<----------------------|                      |
         |   (4) 200 OK |                       |                      |
         |<-------------|                       |                      |
         |              |(5)RS INVITE with SDP  |                      |
         |              |--------------------------------------------->|
         |              |                       |  (6) 200 OK with SDP |
         |              |<---------------------------------------------|
         |(7)CS RTP     |                       |                      |
         |=============>|======================>|                      |
         |<=============|<======================|                      |
         |              |(8)RS RTP              |                      |
         |              |=============================================>|
         |              |=============================================>|
         |              |                       |                      |
         |         Mid call updates(hold/resume/re-invite(new offer)   |
         |              |                       |                      |
         |(9)CS BYE     |                       |                      |
         |------------->|                       |                      |
         |              |(10)CS BYE             |                      |
         |              |---------------------->|                      |
         |              |(11)RS BYE             |                      |
         |              |--------------------------------------------->|
         |              |                       |                      |



   The above call flow can also apply to the case of a centralized
   conference with a mixer.  For clarity, ACKs to INVITEs and 200 OKs to
   BYEs are not shown.  The conference focus can provide the SRC
   functionality since the conference focus has access to all the media
   from each conference participant.  When a recording is requested, the
   SRC delivers the metadata and the media streams to the SRS.  Since
   the conference focus has access to a mixer, the SRC may choose to mix
   the media streams from all participants as a single mixed media
   stream towards the SRS.

   An SRC can use a single recording session to record multiple
   communication sessions.  Every time the SRC wants to record a new
   call, the SRC updates the recording session with a new SDP offer to
   add new recorded streams to the recording session, and
   correspondingly also update the metadata for the new call.




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3.2.  Example 1: Basic Call



               SRC                                                   SRS
               |                                                     |
               |(1) INVITE (metadata snapshot)   F1                  |
               |---------------------------------------------------->|
               |                            200 OK    F2             |
               |<----------------------------------------------------|
               |(3) ACK         F3                                   |
               |---------------------------------------------------->|
               |(4) RTP                                              |
               |====================================================>|
               |====================================================>|
               |====================================================>|
               |====================================================>|
               |(5) UPDATE/RE-INVITE (metadata update 1)     F4      |
               |---------------------------------------------------->|
               |                      200 OK        F5               |
               |<----------------------------------------------------|
               |====================================================>|
               |====================================================>|
               |(7) UPDATE/RE-INVITE (metadata update 2)       F6    |
               |---------------------------------------------------->|
               |                       200 OK         F7             |
               |<----------------------------------------------------|


   Basic call between two Participants A(Ram) and B(Partha) who are part
   of one session.  In this use case each participant sends two Media
   Streams.  Media Streams sent by each participant is received all
   other participants of that CS in this use-case.  Below is the initial
   snapshot sent by SRC in the INVITE to SRS that has complete metadata.
   For the sake of simplicity snippets of SDP is shown.  Here the RS
   stream is unmixed.



      F1  INVITE SRC --------------> SRS

      Content-Type: application/SDP
      ...
      m=audio 49170 RTP/AVP 0
      a=rtpmap:0 PCMU/8000
      a=label:96
      a=sendonly
      ...



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      m=video 49174 RTP/AVPF 96
      a=rtpmap:96 H.264/90000
      a=label:97
      a=sendonly
      ...
      m=audio 51372 RTP/AVP 0
      a=rtpmap:0 PCMU/8000
      a=label:98
      a=sendonly
      ...
      m=video 49176 RTP/AVPF 96
      a=rtpmap:96 H.264/90000
      a=label:99
      a=sendonly
      ....
   <?xml version="1.0" encoding="UTF-8"?>
       <recording xmlns='urn:ietf:params:xml:ns:recording'>
              <dataMode>complete</dataMode>
         <session session_id="hVpd7YQgRW2nD22h7q60JQ==">
            <start-time>2010-12-16T23:41:07Z</start-time>
         </session>
          <participant
             participant_id="srfBElmCRp2QB23b7Mpk0w==">
            <nameID aor=sip:ram@example.com>
             <name xml:lang="it">RamMohan R</name>
            </nameID>
          </participant>
          <participantsessionassoc
             participant_id="srfBElmCRp2QB23b7Mpk0w=="
             session_id="hVpd7YQgRW2nD22h7q60JQ==">
           <associate-time>2010-12-16T23:41:07Z</associate-time>
          </participantsessionassoc>
          <participantstreamassoc
             participant_id="srfBElmCRp2QB23b7Mpk0w==">
             <send>i1Pz3to5hGk8fuXl+PbwCw==</send>
             <send>UAAMm5GRQKSCMVvLyl4rFw==</send>
             <recv>8zc6e0lYTlWIINA6GR+3ag==</recv>
             <recv>EiXGlc+4TruqqoDaNE76ag==</recv>
          </participantstreamassoc>
          <participant
              participant_id="zSfPoSvdSDCmU3A3TRDxAw==">
              <nameID aor=sip:partha@example.com>
               <name xml:lang="it">Parthasarathi R</name>
            </nameID>
          </participant>
          <participantsessionassoc
              participant="zSfPoSvdSDCmU3A3TRDxAw==">
             <associate-time>2010-12-16T23:41:07Z</associate-time>



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          </participantsessionassoc>
          <participantstreamassoc
              participant="zSfPoSvdSDCmU3A3TRDxAw==">
            <send>8zc6e0lYTlWIINA6GR+3ag==</send>
            <send>EiXGlc+4TruqqoDaNE76ag==</send>
            <recv>UAAMm5GRQKSCMVvLyl4rFw==</recv>
            <recv>i1Pz3to5hGk8fuXl+PbwCw==</recv>
          </participantstreamassoc>
          <stream id="UAAMm5GRQKSCMVvLyl4rFw=="
              session="hVpd7YQgRW2nD22h7q60JQ==">
              <label>96</label>
          </stream>
          <stream id="i1Pz3to5hGk8fuXl+PbwCw=="
              session="hVpd7YQgRW2nD22h7q60JQ==">
              <label>97</label>
          </stream>
          <stream id="8zc6e0lYTlWIINA6GR+3ag=="
              session="zSfPoSvdSDCmU3A3TRDxAw==">
              <label>98</label>
          </stream>
          <stream id="EiXGlc+4TruqqoDaNE76ag=="
              session="zSfPoSvdSDCmU3A3TRDxAw==">
              <label>99</label>
          </stream>
     </recording>


3.3.  Example 2: Hold/resume

   Basic call between two Participants A and B. This is the continuation
   of above use-case.  One of the participants(say A) goes on hold and
   then resumes as part of the same session.  The metadata snapshot
   looks as below

   During hold
















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      F4 RE-INVITE SRC-------------------->SRS


      Content-Type: application/SDP
      ...
      m=audio 49170 RTP/AVP 0
      a=rtpmap:0 PCMU/8000
      a=label:96
      a=inactive
      ...
      m=video 49174 RTP/AVPF 96
      a=rtpmap:96 H.264/90000
      a=label:97
      a=inactive
      ...
      m=audio 51372 RTP/AVP 0
      a=rtpmap:0 PCMU/8000
      a=label:98
      a=sendonly
      ...
      m=video 49176 RTP/AVPF 96
      a=rtpmap:96 H.264/90000
      a=label:99
      a=sendonly
      ....

      <?xml version="1.0" encoding="UTF-8"?>
        <recording xmlns='urn:ietf:params:xml:ns:recording'>
          <dataMode>partial</dataMode>
            <participantstreamassoc
             participant="srfBElmCRp2QB23b7Mpk0w=="
             session="hVpd7YQgRW2nD22h7q60JQ==">
             <recv>8zc6e0lYTlWIINA6GR+3ag==</recv>
             <recv>EiXGlc+4TruqqoDaNE76ag==</recv>
            </participantstreamassoc>
            <participantstreamassoc
             participant="zSfPoSvdSDCmU3A3TRDxAw=="
             session="hVpd7YQgRW2nD22h7q60JQ==">
              <send>8zc6e0lYTlWIINA6GR+3ag==</send>
              <send>EiXGlc+4TruqqoDaNE76ag==</send>
             </participantstreamassoc>

           </recording>


   During resume

   The snapshot will look pretty much same as above with just the SDP



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   dir change.



    F5 RE-INVITE SRC-------------------->SRS


      Content-Type: application/SDP
      ...
      m=audio 49170 RTP/AVP 0
      a=rtpmap:0 PCMU/8000
      a=label:96
      a=sendonly
      ...
      m=video 49174 RTP/AVPF 96
      a=rtpmap:96 H.264/90000
      a=label:97
      a=sendonly
      ...
      m=audio 51372 RTP/AVP 0
      a=rtpmap:0 PCMU/8000
      a=label:98
      a=sendonly
      ...
      m=video 49176 RTP/AVPF 96
      a=rtpmap:96 H.264/90000
      a=label:99
      a=sendonly
      ....

      <?xml version="1.0" encoding="UTF-8"?>
        <recording xmlns='urn:ietf:params:xml:ns:recording'>
          <dataMode>partial</dataMode>
            <participantstreamassoc
             participant="srfBElmCRp2QB23b7Mpk0w=="
             session="hVpd7YQgRW2nD22h7q60JQ==">
             <recv>8zc6e0lYTlWIINA6GR+3ag==</recv>
             <recv>EiXGlc+4TruqqoDaNE76ag==</recv>
            </participantstreamassoc>
            <participantstreamassoc
             participant="zSfPoSvdSDCmU3A3TRDxAw=="
             session="hVpd7YQgRW2nD22h7q60JQ==">
              <send>8zc6e0lYTlWIINA6GR+3ag==</send>
              <send>EiXGlc+4TruqqoDaNE76ag==</send>
             </participantstreamassoc>

           </recording>




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3.4.  Example 3: Basic Call with transfer

   Basic call between two Participants A and B is connected as in Use-
   case 1.  Transfer is initiated by one of the participants or by other
   entity(3PCC case).  SRC sends a snapshot of the participant changes
   to SRS.  In this instance participant A(Ram) drops out during the
   transfer and Participant C(Paul) joins the session.  There can be two
   cases here, same session continues after transfer or a new session
   (e.g.  REFER based transfer) is created

   Transfer with same session retained - (.e.g.  RE-INVITE based
   transfer).  Participant A drops out and C is added to the same
   session.  No change to session/group element.  C will be new stream
   element which maps to RS SDP using the same labels in this instance.


      Content-Type: application/SDP
      ...
      m=audio 49170 RTP/AVP 0
      a=rtpmap:0 PCMU/8000
      a=label:96
      a=sendonly
      ...
      m=video 49174 RTP/AVPF 96
      a=rtpmap:96 H.264/90000
      a=label:97
      a=sendonly
      ...
      m=audio 51372 RTP/AVP 0
      a=rtpmap:0 PCMU/8000
      a=label:98
      a=sendonly
      ...
      m=video 49176 RTP/AVPF 96
      a=rtpmap:96 H.264/90000
      a=label:99
      a=sendonly
      ....
   <?xml version="1.0" encoding="UTF-8"?>
       <recording xmlns='urn:ietf:params:xml:ns:recording'>
              <dataMode>partial</dataMode>
          <participantstreamassoc
              participant_id="zSfPoSvdSDCmU3A3TRDxAw==">
             <send>8zc6e0lYTlWIINA6GR+3ag==</send>
             <send>EiXGlc+4TruqqoDaNE76ag==</send>
             <recv>60JAJm9UTvik0Ltlih/Gzw==</recv>
             <recv>AcR5FUd3Edi8cACQJy/3JQ==</recv>
          </participantstreamassoc>



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          <participant
             participant_id="Atnm1ZRnOC6Pm5MApkrDzQ==">
             <nameIDaor=sip:paul@example.com>
              <name xml:lang="it">Paul Kyzivat</name>
            </nameID>
          </participant>
          <participantsessionassoc
             participant_id="Atnm1ZRnOC6Pm5MApkrDzQ=="
             session_id="hVpd7YQgRW2nD22h7q60JQ==">
             <associate-time>2010-12-16T23:41:07Z</associate-time>
          </participantsession>
          <participantstreamassoc
             participant_id="Atnm1ZRnOC6Pm5MApkrDzQ==">
            <send>60JAJm9UTvik0Ltlih/Gzw==</send>
            <send>AcR5FUd3Edi8cACQJy/3JQ==</send>
            <recv>8zc6e0lYTlWIINA6GR+3ag==</recv>
            <recv>EiXGlc+4TruqqoDaNE76ag==</recv>
            <associate-time>2010-12-16T23:41:07Z</associate-time>
          </participantstreamassoc>
          <stream stream_id="60JAJm9UTvik0Ltlih/Gzw=="
              session_id="hVpd7YQgRW2nD22h7q60JQ==">
              <label>96</label>
          </stream>
          <stream stream_id="AcR5FUd3Edi8cACQJy/3JQ=="
              session_id="hVpd7YQgRW2nD22h7q60JQ==">
              <label>97</label>
          </stream>
          <stream stream_id="8zc6e0lYTlWIINA6GR+3ag=="
              session_id="zSfPoSvdSDCmU3A3TRDxAw==">
              <label>98</label>
          </stream>
          <stream stream_id="EiXGlc+4TruqqoDaNE76ag=="
              session_id="zSfPoSvdSDCmU3A3TRDxAw==">
              <label>99</label>
          </stream>
     </recording>


   Transfer with new session - (.e.g.  REFER based transfer).  In this
   case new session is part of same grouping (done by SRC).

   SRC may send an optional snapshot indicating stop for the old
   session.








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          <?xml version="1.0" encoding="UTF-8"?>
      <recording xmlns='urn:ietf:params:xml:ns:recording'>
             <dataMode>Partial</dataMode>
         <session session_id="hVpd7YQgRW2nD22h7q60JQ==">
           <stop-time>2010-12-16T23:41:07Z</stop-time>
         </session>
         <participantsessionassoc
            participant_id="srfBElmCRp2QB23b7Mpk0w=="
            session_id="hVpd7YQgRW2nD22h7q60JQ==">
             <disassociate-time>2010-12-16T23:41:07Z</disassociate-time>
          </participantsessionassoc>
         <participantsessionassoc
            participant_id="zSfPoSvdSDCmU3A3TRDxAw=="
            session_id="hVpd7YQgRW2nD22h7q60JQ==">
            <disasociate-time>2010-12-16T23:41:07Z</disassociate-time>
          </participantsessionassoc>
    </recording>


   SRC sends a snapshot to indicate the participant change and new
   session information after transfer.  In this example the same RS is
   used.


     Content-Type: application/SDP
      ...
      m=audio 49170 RTP/AVP 0
      a=rtpmap:0 PCMU/8000
      a=label:96
      a=sendonly
      ...
      m=video 49174 RTP/AVPF 96
      a=rtpmap:96 H.264/90000
      a=label:97
      a=sendonly
      ...
      m=audio 51372 RTP/AVP 0
      a=rtpmap:0 PCMU/8000
      a=label:98
      a=sendonly
      ...
      m=video 49176 RTP/AVPF 96
      a=rtpmap:96 H.264/90000
      a=label:99
      a=sendonly
      ....
   <?xml version="1.0" encoding="UTF-8"?>
       <recording xmlns='urn:ietf:params:xml:ns:recording'>



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              <dataMode>partial</dataMode>
          <session session_id="bfLZ+NTFEeCNxQTuRyQBmw==">
            <start-time>2010-12-16T23:41:07Z</start-time>
          </session>
          <participant
              participant_id="zSfPoSvdSDCmU3A3TRDxAw==">
              <nameID aor=sip:partha@example.com/>
           </participant>
          <participantsessionassoc
              participant_id="zSfPoSvdSDCmU3A3TRDxAw=="
              session_id="bfLZ+NTFEeCNxQTuRyQBmw==">
              <associate-time>2010-12-16T23:32:03Z</associate-time>
           </participantsessionassoc>
          <participantstreamassoc
              participant_id="zSfPoSvdSDCmU3A3TRDxAw==">
            <send>8zc6e0lYTlWIINA6GR+3ag==</send>
            <send>EiXGlc+4TruqqoDaNE76ag==</send>
            <recv>60JAJm9UTvik0Ltlih/Gzw==</recv>
            <recv>AcR5FUd3Edi8cACQJy/3JQ==</recv>
          </participantstreamassoc>
          <participant
             participant_id="Atnm1ZRnOC6Pm5MApkrDzQ==">
             <nameID aor=sip:paul@example.com/>
          </participant>
          <participantsessionassoc
             participant_id="Atnm1ZRnOC6Pm5MApkrDzQ=="
             session_id="bfLZ+NTFEeCNxQTuRyQBmw==">
           <associate-time>2010-12-16T23:41:07Z</associate-time>
          </participantsessionassoc>
          <participantstreamassoc
             participant_id="Atnm1ZRnOC6Pm5MApkrDzQ==">
           <send>60JAJm9UTvik0Ltlih/Gzw==</send>
           <send>AcR5FUd3Edi8cACQJy/3JQ==</send>
           <recv>8zc6e0lYTlWIINA6GR+3ag==</recv>
           <recv>EiXGlc+4TruqqoDaNE76ag==</recv>
           </participantstreamassoc>
          <stream stream_id="60JAJm9UTvik0Ltlih/Gzw=="
              session_id="bfLZ+NTFEeCNxQTuRyQBmw==">
              <label>96</label>
          </stream>
          <stream stream_id="AcR5FUd3Edi8cACQJy/3JQ=="
              session_id="bfLZ+NTFEeCNxQTuRyQBmw==">
              <label>97</label>
          </stream>
          <stream stream_id="8zc6e0lYTlWIINA6GR+3ag=="
              session_id="bfLZ+NTFEeCNxQTuRyQBmw==">
              <label>98</label>
          </stream>



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          <stream stream_id="EiXGlc+4TruqqoDaNE76ag=="
              session_id="bfLZ+NTFEeCNxQTuRyQBmw==">
              <label>99</label>
          </stream>
     </recording>


3.5.  Example 4: Call disconnect

   This example shows a snapshot of metadata sent by an SRC at CS
   disconnect where the participants of CS are Ram and Partha




           SRC                                                   SRS
               |                                                     |
               |(1) BYE (metadata snapshot)   F1                     |
               |---------------------------------------------------->|
               |                            200 OK    F2             |
               |<----------------------------------------------------|


   F1  BYE SRC  -----------> SRS

   <?xml version="1.0" encoding="UTF-8"?>
       <recording xmlns='urn:ietf:params:xml:ns:recording'>
              <dataMode>Partial</dataMode>
          <session session_id="hVpd7YQgRW2nD22h7q60JQ==">
             <stop-time>2010-12-16T23:41:07Z</stop-time>
          </session>
          <participantsessionassoc
             participant_id="srfBElmCRp2QB23b7Mpk0w=="
             session_id="hVpd7YQgRW2nD22h7q60JQ==">
            <disassociate-time>2010-12-16T23:41:07Z</disassociate-time>
           </participantsessionassoc>

          <participantsessionassoc
             participant_id="zSfPoSvdSDCmU3A3TRDxAw=="
            session_id="hVpd7YQgRW2nD22h7q60JQ==">
             <disasociate-time>2010-12-16T23:41:07Z</disassociate-time>
           </participantsessionassoc>
      </recording>








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3.6.  Example 5: Multiple CS into single RS with mixed stream

   In trading turret, audio mixing is done locally before forwarding to
   the recording server.  Sender and receiver audio is mixed for each
   communication session.  The audio from multiple communication
   sessions is also mixed, or multiplexed, in a single RTP session to
   the recording server.



      F1  INVITE SRC --------------> SRS

      Content-Type: application/SDP
      ...
      m=audio 49170 RTP/AVP 0
      a=rtpmap:0 PCMU/8000
      a=label:96
      a=sendonly
      ...
   <?xml version="1.0" encoding="UTF-8"?>
       <recording xmlns='urn:ietf:params:xml:ns:recording'>
              <dataMode>complete</dataMode>
           <group group_id="7+OTCyoxTmqmqyA/1weDAg==">
                  <associate-time>2010-12-16T23:41:07Z</associate-time>
          </group>
          <session session_id="hVpd7YQgRW2nD22h7q60JQ==">
             <group-ref>7+OTCyoxTmqmqyA/1weDAg==</group-ref>
            <start-time>2010-12-16T23:41:07Z</start-time>
          </session>
         <session session_id="zzlafnvvjlCHllaHF6mn8kkSS==">
             <group-ref>7+OTCyoxTmqmqyA/1weDAg==</group-ref>
            <start-time>2010-12-16T23:43:07Z</start-time>
          </session>
          <participant
             participant_id="srfBElmCRp2QB23b7Mpk0w==">
            <nameID aor=sip:ram@example.com>
             <name xml:lang="it">RamMohan R</name>
            </nameID>
          </participant>
          <participantsessionassoc
             participant_id="srfBElmCRp2QB23b7Mpk0w=="
             session_id="hVpd7YQgRW2nD22h7q60JQ==">
           <associate-time>2010-12-16T23:41:07Z</associate-time>
          </participantsessionassoc>
          <participantstreamassoc
             participant_id="srfBElmCRp2QB23b7Mpk0w==">
             <send>UAAMm5GRQKSCMVvLyl4rFw==</send>
             <recv>UAAMm5GRQKSCMVvLyl4rFw==</recv>



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          </participantstreamassoc>
          <participant
              participant_id="zSfPoSvdSDCmU3A3TRDxAw==">
              <nameID aor=sip:partha@example.com>
               <name xml:lang="it">Parthasarathi R</name>
            </nameID>
          </participant>
          <participantsessionassoc
              participant="zSfPoSvdSDCmU3A3TRDxAw=="
              session="hVpd7YQgRW2nD22h7q60JQ==">
             <associate-time>2010-12-16T23:41:07Z</associate-time>
          </participantsessionassoc>
          <participantsessionassoc
              participant="zSfPoSvdSDCmU3A3TRDxAw=="
              session="zzlafnvvjlCHllaHF6mn8kkSS==">
             <associate-time>2010-12-16T23:43:07Z</associate-time>
          </participantsessionassoc>
          <participantstreamassoc
              participant="zSfPoSvdSDCmU3A3TRDxAw==">
            <send>UAAMm5GRQKSCMVvLyl4rFw==</send>
            <recv>UAAMm5GRQKSCMVvLyl4rFw==</recv>
          </participantstreamassoc>
          <participant
             participant_id="EiXGlc+4TruqqoDaNE76ag==">
            <nameID aor=sip:paul@example.com>
             <name xml:lang="it">Paul</name>
            </nameID>
          </participant>
          <participantsessionassoc
              participant="EiXGlc+4TruqqoDaNE76ag=="
              session="zzlafnvvjlCHllaHF6mn8kkSS==">
             <associate-time>2010-12-16T23:43:07Z</associate-time>
          </participantsessionassoc>
          <participantstreamassoc
              participant="EiXGlc+4TruqqoDaNE76ag==">
            <send>UAAMm5GRQKSCMVvLyl4rFw==</send>
            <recv>UAAMm5GRQKSCMVvLyl4rFw==</recv>
          </participantstreamassoc>

          <stream id="UAAMm5GRQKSCMVvLyl4rFw=="
              session="hVpd7YQgRW2nD22h7q60JQ==">
              <label>96</label>
          </stream>
          <stream id="EiXGlc+4TruqqoDaNE76ag=="
              session="zzlafnvvjlCHllaHF6mn8kkSS==">
              <label>96</label>
          </stream>
     </recording>



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4.  Security Considerations

   There is no security consideration as it is informatioal callflow
   document.


5.  IANA Considerations

   This document has no IANA considerations


6.  Acknowledgement

   Thanks to Ofir Rath for his review comments.


7.  References

7.1.  Normative References

   [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.

7.2.  Informative References

   [I-D.ietf-siprec-metadata]
              R, R., Ravindran, P., and P. Kyzivat, "Session Initiation
              Protocol (SIP) Recording Metadata",
              draft-ietf-siprec-metadata-08 (work in progress),
              October 2012.


Authors' Addresses

   Ram Mohan Ravindranath
   Cisco Systems, Inc.
   Cessna Business Park,
   Kadabeesanahalli Village, Varthur Hobli,
   Sarjapur-Marathahalli Outer Ring Road
   Bangalore, Karnataka  560103
   India

   Email: rmohanr@cisco.com






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   Parthasarathi Ravindran
   Nokia Siemens Networks
   Bangalore, Karnataka
   India

   Email: partha@parthasarathi.co.in


   Paul Kyzivat
   Huawei
   Hudson, MA
   USA

   Email: pkyzivat@alum.mit.edu





































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