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Checking references for intended status: Informational ---------------------------------------------------------------------------- == Unused Reference: 'RFC3265' is defined on line 607, but no explicit reference was found in the text -- Obsolete informational reference (is this intentional?): RFC 4566 (Obsoleted by RFC 8866) == Outdated reference: A later version (-22) exists of draft-ietf-siprec-metadata-04 == Outdated reference: A later version (-18) exists of draft-ietf-siprec-protocol-00 -- Obsolete informational reference (is this intentional?): RFC 3265 (Obsoleted by RFC 6665) Summary: 0 errors (**), 0 flaws (~~), 4 warnings (==), 3 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 SIPREC A. Hutton, Ed. 3 Internet-Draft Siemens Enterprise 4 Intended status: Informational Communications 5 Expires: April 5, 2012 L. Portman, Ed. 6 Nice Systems 7 R. Jain 8 IPC Systems 9 K. Rehor 10 Cisco Systems, Inc. 11 October 3, 2011 13 An Architecture for Media Recording using the Session Initiation 14 Protocol 15 draft-ietf-siprec-architecture-03 17 Abstract 19 Session recording is a critical requirement in many communications 20 environments such as call centers and financial trading. In some of 21 these environments, all calls must be recorded for regulatory, 22 compliance, and consumer protection reasons. Recording of a session 23 is typically performed by sending a copy of a media stream to a 24 recording device. This document describes architectures for 25 deploying session recording solutions in an environment which is 26 based on the Session Initiation Protocol (SIP). 28 Status of this Memo 30 This Internet-Draft is submitted in full conformance with the 31 provisions of BCP 78 and BCP 79. 33 Internet-Drafts are working documents of the Internet Engineering 34 Task Force (IETF). Note that other groups may also distribute 35 working documents as Internet-Drafts. The list of current Internet- 36 Drafts is at http://datatracker.ietf.org/drafts/current/. 38 Internet-Drafts are draft documents valid for a maximum of six months 39 and may be updated, replaced, or obsoleted by other documents at any 40 time. It is inappropriate to use Internet-Drafts as reference 41 material or to cite them other than as "work in progress." 43 This Internet-Draft will expire on April 5, 2012. 45 Copyright Notice 47 Copyright (c) 2011 IETF Trust and the persons identified as the 48 document authors. All rights reserved. 50 This document is subject to BCP 78 and the IETF Trust's Legal 51 Provisions Relating to IETF Documents 52 (http://trustee.ietf.org/license-info) in effect on the date of 53 publication of this document. Please review these documents 54 carefully, as they describe your rights and restrictions with respect 55 to this document. Code Components extracted from this document must 56 include Simplified BSD License text as described in Section 4.e of 57 the Trust Legal Provisions and are provided without warranty as 58 described in the Simplified BSD License. 60 Table of Contents 62 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 63 2. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . 4 64 3. Session Recording Architecture . . . . . . . . . . . . . . . . 5 65 3.1. Location of the Session Recording Client . . . . . . . . . 5 66 3.1.1. B2BUA acts as a Session Recording Client . . . . . . . 5 67 3.1.2. Endpoint acts as Session Recording Client . . . . . . 7 68 3.1.3. A SIP Proxy cannot be a Session Recording Client . . . 7 69 3.1.4. Interaction with MEDIACTRL . . . . . . . . . . . . . . 8 70 3.1.5. Interaction with Conference Focus . . . . . . . . . . 9 71 3.2. Establishing the Recording Session . . . . . . . . . . . . 10 72 3.2.1. Session Recording Client Initiated Recording . . . . . 11 73 3.2.2. Session Recording Server Initiated Recording . . . . . 11 74 3.2.3. Pause/Resume Recording Session . . . . . . . . . . . . 12 75 3.2.4. Media Stream Mixing . . . . . . . . . . . . . . . . . 12 76 3.2.5. Media Transcoding . . . . . . . . . . . . . . . . . . 12 77 3.3. Media Recording Metadata . . . . . . . . . . . . . . . . . 12 78 3.3.1. Contents of recording metadata . . . . . . . . . . . . 13 79 3.3.2. Mechanisms for delivery of metadata to Session 80 Recording Server . . . . . . . . . . . . . . . . . . . 13 81 3.4. Notifications to the Recorded User Agents . . . . . . . . 13 82 3.5. Preventing the recording of a SIP session . . . . . . . . 13 83 4. IANA considerations . . . . . . . . . . . . . . . . . . . . . 13 84 5. Security considerations . . . . . . . . . . . . . . . . . . . 13 85 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 14 86 7. Informative References . . . . . . . . . . . . . . . . . . . . 14 87 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15 89 1. Introduction 91 Session recording is a critical requirement in many communications 92 environments such as call centers and financial trading. In some of 93 these environments, all calls must be recorded for regulatory, 94 compliance, and consumer protection reasons. Recording of a session 95 is typically performed by sending a copy of a media stream to a 96 recording device. This document describes architectures for 97 deploying session recording solutions in an environment which is 98 based on the Session Initiation Protocol (SIP) the requirements for 99 which are described in [RFC6341]. 101 This document focuses on how sessions are established between a 102 Session Recording Client (SRC) and the Session Recording Server (SRS) 103 for the purpose of conveying the Replicated Media and Media Recording 104 Metadata (e.g. Identity of parties involved) relating to the 105 Communication Session. 107 Once the Replicated Media and Media Recording Metadata have been 108 received by the Session Recording Server they will typically be 109 archived for retrieval at a later time. The procedures relating to 110 the archiving and retrieval of this information in outside the scope 111 of this document. 113 This document only considers active recording, where the Session 114 Recording Client purposefully streams media to a Session Recording 115 Server. Passive recording, where a recording device detects media 116 directly from the network (E.g. using port mirroring techniques), is 117 outside the scope of this document. In addition, lawful intercept is 118 outside the scope of this document which takes account of the IETF 119 policy on wiretapping [RFC2804]. 121 The Recording Session that is established between the Session 122 Recording Client and the Session Recording Server uses the normal 123 procedures for establishing INVITE initiated dialogs as specified in 124 [RFC3261] and uses SDP for describing the media to be used during the 125 session as specified in [RFC4566]. However it is intended that some 126 extensions to SIP (E.g. Headers, Option Tags, Etc.) will be defined 127 to support the requirements for media recording. The Replicated 128 Media is required to be sent in real-time to the Session Recording 129 Server and is not buffered by the Session Recording Client to allow 130 for real-time analysis of the media by the Session Recording Server. 132 2. Definitions 134 Session Recording Server (SRS): A Session Recording Server (SRS) is 135 a SIP User Agent (UA) that acts as the sink of the recorded media. 136 An SRS is a logical function that typically archives media for 137 extended durations of time and provides interfaces for search and 138 retrieval of the archived media. An SRS is typically implemented as 139 a multi-port device that is capable of receiving media from several 140 sources simultaneously. An SRS is the sink of the recorded session 141 metadata. Note that the term "Server" does not imply the SRS is the 142 server side of a signaling protocol as the SRS may be the initiator 143 of recording requests. 145 Session Recording Client (SRC): A Session Recording Client (SRC) is 146 a SIP User Agent (UA) that acts as the source of the recorded media, 147 sending it to the Session Recording Server. A Session Recording 148 Client is a logical function. Its capabilities may be implemented 149 across one or more physical devices. In practice, a Session 150 Recording Client could be a personal device (such as a SIP phone), a 151 SIP Media Gateway (MG), a Session Border Controller (SBC), Media 152 Server, or an Application Server. The Session Recording Client is 153 also the source of the recorded session metadata. 155 Communication Session (CS): A SIP session created between two or 156 more UA's for the purpose of communication which may be recorded. 158 Recording Session (RS): The session created between an Session 159 Recording Client and Session Recording Server for the purpose of 160 recording a Communication Session. 162 Recording aware UA: A SIP User Agent that is aware of SIP extensions 163 associated with the Communication Session. Such extensions may be 164 used to notify the SIP UA that a session is being recorded or to all 165 the SIP UA to express preferences as to whether a recording should be 166 started, paused, resumed or stopped. 168 Media Recording Metadata (MRM): The metadata describing the 169 communication session that is required by the Session Recording 170 Server. This will include for example the identity of users that 171 participate in the Communication Session and dialog state. Typically 172 this metadata is archived with the replicated media at the Session 173 Recording Server. The media recording metadata is delivered in real- 174 time to the Session Recording Server. 176 Replicated Media: A copy of the media associated with the 177 Communication Session created by the Session Recording Client and 178 sent to the Session Recording Server. It may contain all the media 179 associated with the communication session (E.g. Audio and Video) or 180 just a subset (E.g. Audio). 182 3. Session Recording Architecture 184 3.1. Location of the Session Recording Client 186 This section contains some example session recording architectures 187 showing how the Session Recording Client is a logical function that 188 can be located in or split between various physical components. 190 3.1.1. B2BUA acts as a Session Recording Client 192 A SIP B2BUA which has access to the media that is to be recorded may 193 act as a Session Recording Client. The B2BUA may already be aware 194 that a session needs to be recorded before the initial establishment 195 of the communication session or the decision to record the session 196 may occur after the session has been established. 198 If the B2BUA/SRC makes the decision to initiate the Recording Session 199 (RS) then it will initiate the establishment of a SIP Session by 200 sending an INVITE to the Session Recording Server. 202 If the Session Recording Server makes the decision to initiate the 203 recording session then it will initiate the establishment of a SIP 204 Session by sending an INVITE to the B2BUA/Session Recording Client. 206 The RS INVITE will need to contain information which identifies the 207 session as being established for the purposes of recording and 208 prevents the session from being accidently rerouted to a UA which is 209 not a SRS. 211 The B2BUA/SRC is responsible for notifying the UA's involved in the 212 communication session that the session is being recorded. 214 The B2BUA/SRC is responsible for honoring any indication from 215 recording aware UA's or through some configured policies that the 216 communication session must not be recorded. 218 +-----------+ 219 (Recording Session) | Session | 220 +------SIP------>| Recording | 221 | | Server | 222 | +--RTP/RTCP-->| (SRS) | 223 | | +-----------+ 224 V | ^ 225 +-------------+ | 226 | | | 227 | |-- MetaData -+ 228 | | 229 | B2BUA | 230 | | 231 | Session | 232 +--------+ | Recording | +---------+ 233 | |<- SIP ->| Client |<- SIP ->| | 234 | UA-A | | (SRC) | | UA-B | 235 | |<- RTP ->| |<- RTP ->| | 236 +--------+ | | +---------+ 237 +-------------+ 238 |____________________________________________________| 239 (Communication Session) 241 Figure 1: B2BUA Acts as the Session Recording Client. 243 3.1.2. Endpoint acts as Session Recording Client 245 A SIP Endpoint / User Agent may act as a Session Recording Client in 246 which case the endpoint sends the Replicated Media to the Session 247 Recording Server 249 If the endpoint makes the decision to initiate the Recording Session 250 then it will initiate the establishment of a SIP Session by sending 251 an INVITE to the Session Recording Server. 253 If the Session Recording Server makes the decision to initiate the 254 Recording Session then it will initiate the establishment of a SIP 255 Session by sending an INVITE to the endpoint. 257 (Recording Session) +-----------+ 258 +----------SIP------>| | 259 | +----RTP/RTCP---->| Session | 260 | | | Recording | 261 | | | Server | 262 | | +-- Metadata -->| (SRS) | 263 | | | | | 264 | | | +-----------+ 265 | | | 266 | | | 267 | | | 268 | | | 269 V | | (Communication Session) 270 +--+------+ +---------+ 271 | |<-------SIP--------->| | 272 | UA-A | | UA-B | 273 | (SRC) |<-----RTP/RTCP------>| | 274 +---------+ +---------+ 276 Figure 2: SIP Endpoint acts as the Session Recording Client 278 3.1.3. A SIP Proxy cannot be a Session Recording Client 280 A SIP Proxy is unable to act as an SRC because it does not have 281 access to the media and therefore has no way of enabling the delivery 282 of the replicated media to the SRS 284 3.1.4. Interaction with MEDIACTRL 286 The mediactrl architecture [RFC5567] describes an architecure in 287 which an application server (AS) controls a Media Server (MS) which 288 may be used for purposes such as conferencing and recording media 289 streams. In the [RFC5567] architecure the AS typically uses SIP 290 Third Party Call Control (3PCC) to instruct the SIP UA's to direct 291 their media to the Media Server. 293 The Session Recording Client and Session Recording Server described 294 in this document may act as an application server as described in 295 [RFC5567] and therefore may when further decomposed be made up of an 296 application server which uses a mediactrl interface to control a 297 media server for the purpose of recording the media streams however 298 this interface is considered outside the scope of this document. 300 In addition, any appropriate control protocols such as RTC-Web can be 301 used for such decomposition. 303 Session Recording Server (SRS) 304 +----------------------------------------+ 305 | | 306 (Recording Session) | +-----------+ +------------+ | 307 +------------SIP----|->| | | | | 308 | | | MediaCtrl |MEDIACTRL | Media | | 309 | | |Application|<-------->| Server | | 310 | +-----Metadata--->| Server | | (Recorder)| | 311 | | | | | | | | 312 | | | +-----------+ +------------+ | 313 | | | ^ | 314 | | +------------------------------|---------+ 315 | | +--------------- RTP/RTCP -----------------+ 316 | | | 317 V | V 318 +---+------+ +---------+ 319 | |<-------SIP-------------->| | 320 | UA-A | (Communication Session) | UA-B | 321 | (SRC) |<-------RTP/RTCP--------->| | 322 +----------+ +---------+ 324 Figure 3: Example of Session Recording Server using MEDIACTRL 325 +----------+ 326 (Recording Session) | Session | 327 +-----------SIP------------------------->|Recording | 328 | | Server | 329 | | (SRS) | 330 | UA-A Session Recording Client (SRC) +----------+ 331 +----------------------------------------+ | 332 | | | 333 | +-----------+ +------------+ | | 334 | | | Control | |<----RTP---+ +---------+ 335 | | UA | Protocol | Media | | | | 336 | |Application|<-------->| Server | |<----SIP----->| UA-B | 337 | | Server | | |<-----RTP------>| | 338 | | | | | | +---------+ 339 | +-----------+ +------------+ | 340 | | 341 +----------------------------------------+ 342 Figure 4: Example of Session Recording Client decomposition 344 3.1.5. Interaction with Conference Focus 346 In the case of a centralised conference a combination of the 347 conference focus and mixer [RFC4353] may act as a SRC and therefore 348 provide the SRS with the replicated media and associated media 349 recording metadata. In this arrangement the SRC is able to provide 350 media and metadata relating to each of the participants, including, 351 for example, any side conversations where the media passes through 352 the mixer 354 The conference focus may also act as a Recording Aware UA in the case 355 when one of the participants acts as a SRC. 357 In an alternative arrangement a SIP endpoint which is a conference 358 participant can act as an SRC. The SRC will in this case have access 359 to the media and metadata relating to that particular participant and 360 may be able to obtain additional metadata from the conference focus. 361 The SRC may for example use the conference event package as described 362 in [RFC4575] to obtain information about other participants which it 363 provides to the SRS within the media recording metadata. 365 The SRC may be involved in the conference from the very beginning or 366 may join at some later point of time. 368 User 1 369 +-----------+ 370 | | 371 | | 372 |Participant| 373 | 1 | 374 | | 375 +-----------+ 376 |SIP 377 |Dialog 378 |1 379 User 2 | Recording 380 +-----------+ +-----------+ Session ************* 381 | | | |--------------* * 382 | | | |----RTP 1 --->* * 383 |Participant|-----------| Focus/SRC |----RTP 2 --->* SRS * 384 | 2 | SIP | |----RTP 3 --->* * 385 | | Dialog | | * * 386 +-----------+ 2 +-----------+ ************* 387 | 388 |SIP 389 |Dialog 390 |3 391 | 392 +-----------+ 393 | | 394 | | 395 |Participant| 396 | 3 | 397 | | 398 +-----------+ 399 User 3 401 Figure 5: Conference Focus acting as an SRC. 403 3.2. Establishing the Recording Session 405 The Session Recording Client or the Session Recording Server may 406 initiate the Recording Session. 408 It should be noted that the Recording Session is independent from the 409 Communication Session that is being recorded at both the SIP dialog 410 level and at the session level. 412 Concerning media negotiation, regular SIP/SDP capabilities should be 413 used, and existing transcoding capabilities should not be precluded 415 3.2.1. Session Recording Client Initiated Recording 417 When the Session Recording Client initiates the Recording Session for 418 the purpose of conveying media to the Session Recording Server it 419 performs the following actions. 421 o The SRC is provisioned with a URI for the SRS, which is resolved 422 through normal [RFC3263] procedures. 424 o Initiates the dialog by sending an INVITE request to the Session 425 Recording Server. The dialog is established according to the 426 normal procedures for establishing an INVITE initiated dialog as 427 specified in [RFC3261]. 429 o Include in the INVITE an indication that the session is 430 established for the purpose of recording the associated media. 431 Possible mechanisms for this include using the Require header 432 and/or a new media feature tag similar to the use of "isfocus" as 433 defined in [RFC3840] 435 o If the Replicated Media is to be started immediately then the 436 Session Recording Client will include an SDP attribute of 437 "a=sendonly" for each media line or "a=inactive" if it is not 438 ready to transmit the media. 440 o The Recording Session may replicate all media associated with the 441 Communication Session or only a subset. 443 o Replicate the media streams that are to be recorded and transmit 444 the media to the Session Recording Server. 446 3.2.2. Session Recording Server Initiated Recording 448 When the Session Recording Server initiates the media recording 449 session with the Session Recording Client it performs the following 450 actions. 452 o Send an INVITE request to the Session Recording Client 454 o Include in the INVITE an indication that the session is 455 established for the purpose of recording the associated media. 456 Possible mechanisms for this include using the Require header or a 457 media feature tag similar to the use of "isfocus" as defined in 458 [RFC3840] 460 o Identify the session that is to be recorded - Possibly using the 461 Join header [RFC3911] 463 o If the Recording Session is to be started immediately then the 464 Session Recording Client will include an SDP attribute of 465 "a=recvonly" for each media line or "a=inactive" if it is not 466 ready to receive the media 468 If the Session Recording Server does not have prior knowledge of what 469 media streams are available to be recorded it can make use of an 470 offerless INVITE which allows the Session Recording Client to make 471 the initial SDP offer. 473 3.2.3. Pause/Resume Recording Session 475 The Session Recording Server or the Session Recording Client may 476 pause the recording by changing the SDP direction attribute to 477 "inactive" and resume the recording by changing the direction back to 478 "recvonly" or "sendonly". 480 3.2.4. Media Stream Mixing 482 In a basic session involving only audio there are typically two 483 audio/RTP streams between the two UA's involved transporting media in 484 each direction. When recording this media the two streams may be 485 mixed at the SRC before being transmitted to the SRS or it may be a 486 requirement of the recording server that the media streams are not 487 mixed and are sent to the SRS as two separate streams. The case when 488 media is mixed at the SRC is simple as only a single media stream is 489 required to be sent to the SRS. However in the case when the media 490 streams are not mixed then the SDP offer sent to the SRS must 491 describe two separate media streams. 493 3.2.5. Media Transcoding 495 The communication session (CS) and the recording session (RS) are 496 negotiated separately using a standard SDP offer/answer exchange 497 which may result in the SRC having to perform media transcoding 498 between the two sessions. If the SRC is not capable of performing 499 media transcoding it may limit the media formats in the offer to the 500 SRS depending on what media is negotiated on the CS or may limit what 501 it includes in the offer on the CS if it has prior knowledge of the 502 media formats supported by the SRS. However typically the SRS will 503 be the more capable device which can provide a wide range of media 504 format options to the SRC and may also be able to make use of a media 505 transcoder as detailed in [RFC5369]. 507 3.3. Media Recording Metadata 508 3.3.1. Contents of recording metadata 510 The metadata model is defined in [I-D.ietf-siprec-metadata]. 512 3.3.2. Mechanisms for delivery of metadata to Session Recording Server 514 The SRS obtains session recording metadata from the SRC. The 515 metadata is transported via SIP based mechanisms as specified in 516 [I-D.ietf-siprec-protocol] 518 It is also possible that metadata is transported via non SIP based 519 mechanisms but these are considered out of scope. 521 3.4. Notifications to the Recorded User Agents 523 Typically a user that is involved in a session that is to be recorded 524 is notified by an announcement at the beginning of the session or may 525 receive some warning tones within the media. However the 526 standardization of media recording protocols when using SIP enable an 527 indication that the call is being recorded to be included in the SIP 528 requests and responses associated with that communication session. 530 It is the Session Recording Client that provides the notification to 531 all SIP UA's for which it is replicating received media for the 532 purpose of recording including the local user if the Session 533 Recording Client is a SIP endpoint. 535 3.5. Preventing the recording of a SIP session 537 A Recording Aware UA may during the initial session establishment or 538 during an established session provide an indication of their 539 preference with regard to recording the media in the communication 540 session. The mechanism for this are specified in 541 [I-D.ietf-siprec-protocol] 543 4. IANA considerations 545 None. 547 5. Security considerations 549 The Recording Session is fundamentally a standard SIP dialog and 550 media session and therefore make use of existing SIP security 551 mechanisms for securing the Recording Session and Media Recording 552 Metadata. 554 The intended use of this architecture is only for the case where the 555 users are aware of that they are being recorded and the architecture 556 provides the means for the Session Recording Client to notify users 557 that they are being recorded. 559 This architectural solution is not intended to support lawful 560 intercept which in contrast requires that users are not informed. 562 It is the responsibility of the Session Recording Server to protect 563 the Replicated Media and Media Recording Metadata once it has been 564 received and archived. 566 6. Acknowledgements 568 Thanks to John Elwell, Alan Johnson, Cullen Jennings, Hadriel Kaplan, 569 Henry Lum, Paul Kyzivat, Parthasarathi R, Ram Mohan R, and Charles 570 Eckel for their significant contributions and assistance with this 571 document and Working Group, and to all the members of the SIPREC WG 572 mailing list for providing valuable input to this work. 574 7. Informative References 576 [RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, 577 A., Peterson, J., Sparks, R., Handley, M., and E. 578 Schooler, "SIP: Session Initiation Protocol", RFC 3261, 579 June 2002. 581 [RFC3263] Rosenberg, J. and H. Schulzrinne, "Session Initiation 582 Protocol (SIP): Locating SIP Servers", RFC 3263, 583 June 2002. 585 [RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session 586 Description Protocol", RFC 4566, July 2006. 588 [RFC3911] Mahy, R. and D. Petrie, "The Session Initiation Protocol 589 (SIP) "Join" Header", RFC 3911, October 2004. 591 [RFC6341] Rehor, K., Portman, L., Hutton, A., and R. Jain, "Use 592 Cases and Requirements for SIP-Based Media Recording 593 (SIPREC)", RFC 6341, August 2011. 595 [I-D.ietf-siprec-metadata] 596 R, R., Ravindran, P., and P. Kyzivat, "Session Initiation 597 Protocol (SIP) Recording Metadata", 598 draft-ietf-siprec-metadata-04 (work in progress), 599 September 2011. 601 [I-D.ietf-siprec-protocol] 602 Portman, L., Lum, H., Johnston, A., and A. Hutton, 603 "Session Recording Protocol", 604 draft-ietf-siprec-protocol-00 (work in progress), 605 August 2011. 607 [RFC3265] Roach, A., "Session Initiation Protocol (SIP)-Specific 608 Event Notification", RFC 3265, June 2002. 610 [RFC3840] Rosenberg, J., Schulzrinne, H., and P. Kyzivat, 611 "Indicating User Agent Capabilities in the Session 612 Initiation Protocol (SIP)", RFC 3840, August 2004. 614 [RFC4353] Rosenberg, J., "A Framework for Conferencing with the 615 Session Initiation Protocol (SIP)", RFC 4353, 616 February 2006. 618 [RFC4575] Rosenberg, J., Schulzrinne, H., and O. Levin, "A Session 619 Initiation Protocol (SIP) Event Package for Conference 620 State", RFC 4575, August 2006. 622 [RFC5567] Melanchuk, T., "An Architectural Framework for Media 623 Server Control", RFC 5567, June 2009. 625 [RFC5369] Camarillo, G., "Framework for Transcoding with the Session 626 Initiation Protocol (SIP)", RFC 5369, October 2008. 628 [RFC2804] IAB and IESG, "IETF Policy on Wiretapping", RFC 2804, 629 May 2000. 631 Authors' Addresses 633 Andrew Hutton (editor) 634 Siemens Enterprise Communications 635 Hofmannstrasse 51 636 Munich D-81379 637 Germany 639 Email: andrew.hutton@siemens-enterprise.com 640 Leon Portman (editor) 641 Nice Systems 642 8 Hapnina 643 Ra'anana 43017 644 Israel 646 Email: leon.portman@nice.com 648 Rajnish Jain 649 IPC Systems 650 777 Commerce Drive 651 Fairfield, CT 06825 652 USA 654 Email: rajnish.jain@ipc.com 656 Ken Rehor 657 Cisco Systems, Inc. 658 170 West Tasman Drive 659 San Jose, CA 95134-1706 660 USA 662 Email: krehor@cisco.com