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'6') (Obsoleted by RFC 8550) == Outdated reference: A later version (-16) exists of draft-ietf-bfcpbis-rfc4582bis-04 ** Obsolete normative reference: RFC 4572 (ref. '10') (Obsoleted by RFC 8122) ** Obsolete normative reference: RFC 4566 (ref. '11') (Obsoleted by RFC 8866) ** Obsolete normative reference: RFC 6347 (ref. '12') (Obsoleted by RFC 9147) ** Obsolete normative reference: RFC 4582 (ref. '14') (Obsoleted by RFC 8855) ** Obsolete normative reference: RFC 4583 (ref. '15') (Obsoleted by RFC 8856) Summary: 6 errors (**), 0 flaws (~~), 3 warnings (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 BFCPbis Working Group G. Camarillo 3 Internet-Draft Ericsson 4 Obsoletes: 4583 (if approved) T. Kristensen, Ed. 5 Intended status: Standards Track Cisco 6 Expires: January 15, 2013 July 14, 2012 8 Session Description Protocol (SDP) Format for Binary Floor Control 9 Protocol (BFCP) Streams 10 draft-ietf-bfcpbis-rfc4583bis-02 12 Abstract 14 This document specifies how to describe Binary Floor Control Protocol 15 (BFCP) streams in Session Description Protocol (SDP) descriptions. 16 User agents using the offer/answer model to establish BFCP streams 17 use this format in their offers and answers. 19 This document obsoletes RFC 4583. Changes from RFC 4583 are 20 summarized in section 12. 22 Status of this Memo 24 This Internet-Draft is submitted in full conformance with the 25 provisions of BCP 78 and BCP 79. 27 Internet-Drafts are working documents of the Internet Engineering 28 Task Force (IETF). Note that other groups may also distribute 29 working documents as Internet-Drafts. The list of current Internet- 30 Drafts is at http://datatracker.ietf.org/drafts/current/. 32 Internet-Drafts are draft documents valid for a maximum of six months 33 and may be updated, replaced, or obsoleted by other documents at any 34 time. It is inappropriate to use Internet-Drafts as reference 35 material or to cite them other than as "work in progress." 37 This Internet-Draft will expire on January 15, 2013. 39 Copyright Notice 41 Copyright (c) 2012 IETF Trust and the persons identified as the 42 document authors. All rights reserved. 44 This document is subject to BCP 78 and the IETF Trust's Legal 45 Provisions Relating to IETF Documents 46 (http://trustee.ietf.org/license-info) in effect on the date of 47 publication of this document. Please review these documents 48 carefully, as they describe your rights and restrictions with respect 49 to this document. Code Components extracted from this document must 50 include Simplified BSD License text as described in Section 4.e of 51 the Trust Legal Provisions and are provided without warranty as 52 described in the Simplified BSD License. 54 This document may contain material from IETF Documents or IETF 55 Contributions published or made publicly available before November 56 10, 2008. The person(s) controlling the copyright in some of this 57 material may not have granted the IETF Trust the right to allow 58 modifications of such material outside the IETF Standards Process. 59 Without obtaining an adequate license from the person(s) controlling 60 the copyright in such materials, this document may not be modified 61 outside the IETF Standards Process, and derivative works of it may 62 not be created outside the IETF Standards Process, except to format 63 it for publication as an RFC or to translate it into languages other 64 than English. 66 Table of Contents 68 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 69 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 70 3. Fields in the 'm' Line . . . . . . . . . . . . . . . . . . . . 4 71 4. Floor Control Server Determination . . . . . . . . . . . . . . 5 72 5. The 'confid' and 'userid' SDP Attributes . . . . . . . . . . . 7 73 6. Association between Streams and Floors . . . . . . . . . . . . 7 74 7. TCP Connection Management . . . . . . . . . . . . . . . . . . 8 75 8. Authentication . . . . . . . . . . . . . . . . . . . . . . . . 8 76 9. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 77 10. Security Considerations . . . . . . . . . . . . . . . . . . . 11 78 11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 79 11.1. Registration of SDP 'proto' Values . . . . . . . . . . . 11 80 11.2. Registration of the SDP 'floorctrl' Attribute . . . . . . 11 81 11.3. Registration of the SDP 'confid' Attribute . . . . . . . 12 82 11.4. Registration of the SDP 'userid' Attribute . . . . . . . 12 83 11.5. Registration of the SDP 'floorid' Attribute . . . . . . . 13 84 12. Changes from RFC 4583 . . . . . . . . . . . . . . . . . . . . 13 85 13. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 14 86 14. Normative References . . . . . . . . . . . . . . . . . . . . . 14 87 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15 89 1. Introduction 91 As discussed in the BFCP (Binary Floor Control Protocol) 92 specification [8], a given BFCP client needs a set of data in order 93 to establish a BFCP connection to a floor control server. These data 94 include the transport address of the server, the conference 95 identifier, and the user identifier. 97 One way for clients to obtain this information is to use an offer/ 98 answer [4] exchange. This document specifies how to encode this 99 information in the SDP session descriptions that are part of such an 100 offer/answer exchange. 102 User agents typically use the offer/answer model to establish a 103 number of media streams of different types. Following this model, a 104 BFCP connection is described as any other media stream by using an 105 SDP 'm' line, possibly followed by a number of attributes encoded in 106 'a' lines. 108 2. Terminology 110 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 111 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 112 "OPTIONAL" in this document are to be interpreted as described in BCP 113 14, RFC 2119 [1] and indicate requirement levels for compliant 114 implementations. 116 3. Fields in the 'm' Line 118 This section describes how to generate an 'm' line for a BFCP stream. 120 According to the SDP specification [11], the 'm' line format is the 121 following: 123 m= ... 125 The media field MUST have a value of "application". 127 The port field is set following the rules in [7]. Depending on the 128 value of the 'setup' attribute (discussed in Section 7), the port 129 field contains the port to which the remote endpoint will direct BFCP 130 messages or is irrelevant (i.e., the endpoint will initiate the 131 connection towards the remote endpoint) and should be set to a value 132 of 9, which is the discard port. A port field value of zero has the 133 standard SDP meaning (i.e., rejection of the media stream). 135 We define four new values for the transport field: TCP/BFCP, TCP/TLS/ 136 BFCP, UDP/BFCP, and UDP/TLS/BFCP. TCP/BFCP is used when BFCP runs 137 directly on top of TCP, TCP/TLS/BFCP is used when BFCP runs on top of 138 TLS, which in turn runs on top of TCP. Similarly, UDP/BFCP is used 139 when BFCP runs directly on top of UDP, and UDP/TLS/BFCP is used when 140 BFCP runs on top of DTLS [12], which in turn runs on top of UDP. 142 The fmt (format) list is ignored for BFCP. The fmt list of BFCP 'm' 143 lines SHOULD contain a single "*" character. 145 The following is an example of an 'm' line for a BFCP connection: 147 m=application 50000 TCP/TLS/BFCP * 149 4. Floor Control Server Determination 151 When two endpoints establish a BFCP stream, they need to determine 152 which of them acts as a floor control server. In the most common 153 scenario, a client establishes a BFCP stream with a conference server 154 that acts as the floor control server. Floor control server 155 determination is straight forward because one endpoint can only act 156 as a client and the other can only act as a floor control server. 158 However, there are scenarios where both endpoints could act as a 159 floor control server. For example, in a two-party session that 160 involves an audio stream and a shared whiteboard, the endpoints need 161 to decide which party will be acting as the floor control server. 163 Furthermore, there are situations where both the offerer and the 164 answerer act as both clients and floor control servers in the same 165 session. For example, in a two-party session that involves an audio 166 stream and a shared whiteboard, one party acts as the floor control 167 server for the audio stream and the other acts as the floor control 168 server for the shared whiteboard. 170 We define the 'floorctrl' SDP media-level attribute to perform floor 171 control determination. Its Augmented BNF syntax [2] is: 173 floor-control-attribute = "a=floorctrl:" role *(SP role) 174 role = "c-only" / "s-only" / "c-s" 176 The offerer includes this attribute to state all the roles it would 177 be willing to perform: 179 c-only: The offerer would be willing to act as a floor control 180 client only. 182 s-only: The offerer would be willing to act as a floor control 183 server only. 185 c-s: The offerer would be willing to act both as a floor control 186 client and as a floor control server. 188 If an SDP media description in an offer contains a 'floorctrl' 189 attribute, the answerer accepting that media MUST include one in the 190 corresponding media description of the answer. The answerer includes 191 this attribute to state which role the answerer will perform. That 192 is, the answerer chooses one of the roles the offerer is willing to 193 perform and generates an answer with the corresponding role for the 194 answerer. Table 1 shows the corresponding roles for an answerer, 195 depending on the offerer's role. 197 +---------+----------+ 198 | Offerer | Answerer | 199 +---------+----------+ 200 | c-only | s-only | 201 | s-only | c-only | 202 | c-s | c-s | 203 +---------+----------+ 205 Table 1: Roles 207 The following are the descriptions of the roles when they are chosen 208 by an answerer: 210 c-only: The answerer will act as a floor control client. 211 Consequently, the offerer will act as a floor control server. 213 s-only: The answerer will act as a floor control server. 214 Consequently, the offerer will act as a floor control client. 216 c-s: The answerer will act both as a floor control client and as a 217 floor control server. Consequently, the offerer will also act 218 both as a floor control client and as a floor control server. 220 Endpoints that use the offer/answer model to establish BFCP 221 connections MUST support the 'floorctrl' attribute. A floor control 222 server acting as an offerer or as an answerer SHOULD include this 223 attribute in its session descriptions. 225 If the 'floorctrl' attribute is not used in an offer/answer exchange, 226 by default the offerer and the answerer will act as a floor control 227 client and as a floor control server, respectively. 229 The following is an example of a 'floorctrl' attribute in an offer. 230 When this attribute appears in an answer, it only carries one role: 232 a=floorctrl:c-only s-only c-s 234 5. The 'confid' and 'userid' SDP Attributes 236 We define the 'confid' and the 'userid' SDP media-level attributes. 237 These attributes are used by a floor control server to provide a 238 client with a conference ID and a user ID, respectively. Their 239 Augmented BNF syntax [2] is: 241 confid-attribute = "a=confid:" conference-id 242 conference-id = token 243 userid-attribute = "a=userid:" user-id 244 user-id = token 246 The 'confid' and the 'userid' attributes carry the decimal integer 247 representation of a conference ID and a user ID, respectively. 249 Endpoints that use the offer/answer model to establish BFCP 250 connections MUST support the 'confid' and the 'userid' attributes. A 251 floor control server acting as an offerer or as an answerer SHOULD 252 include these attributes in its session descriptions. 254 6. Association between Streams and Floors 256 We define the 'floorid' SDP media-level attribute. Its Augmented BNF 257 syntax [2] is: 259 floor-id-attribute = "a=floorid:" token [" mstrm:" token *(SP token)] 261 The 'floorid' attribute is used in the SDP media description for BFCP 262 media. It defines a floor identifier and, possibly, associates it 263 with one or more media streams. The token representing the floor ID 264 is the integer representation of the Floor ID to be used in BFCP. 265 The token representing the media stream is a pointer to the media 266 stream, which is identified by an SDP label attribute [9]. 268 Endpoints that use the offer/answer model to establish BFCP 269 connections MUST support the 'floorid' and the 'label' attributes. A 270 floor control server acting as an offerer or as an answerer SHOULD 271 include these attributes in its session descriptions. 273 Note: In [15] 'm-stream' was erroneously used in Section 9. Although 274 the example was non-normative, it is implemented by some vendors. 275 Therefore, it is RECOMMENDED to support parsing and interpreting 276 'm-stream' the same way as 'mstrm' when receiving. 278 7. TCP Connection Management 280 The management of the TCP connection used to transport BFCP is 281 performed using the 'setup' and 'connection' attributes, as defined 282 in [7]. 284 The 'setup' attribute indicates which of the endpoints (client or 285 floor control server) initiates the TCP connection. The 'connection' 286 attribute handles TCP connection reestablishment. 288 The BFCP specification [8] describes a number of situations when the 289 TCP connection between a client and the floor control server needs to 290 be reestablished. However, that specification does not describe the 291 reestablishment process because this process depends on how the 292 connection was established in the first place. BFCP entities using 293 the offer/answer model follow the following rules. 295 When the existing TCP connection is reset following the rules in [8], 296 the client SHOULD generate an offer towards the floor control server 297 in order to reestablish the connection. If a TCP connection cannot 298 deliver a BFCP message and times out, the entity that attempted to 299 send the message (i.e., the one that detected the TCP timeout) SHOULD 300 generate an offer in order to reestablish the TCP connection. 302 Endpoints that use the offer/answer model to establish BFCP 303 connections MUST support the 'setup' and 'connection' attributes. 305 8. Authentication 307 When a BFCP connection is established using the offer/answer model, 308 it is assumed that the offerer and the answerer authenticate each 309 other using some mechanism. Once this mutual authentication takes 310 place, all the offerer and the answerer need to ensure is that the 311 entity they are receiving BFCP messages from is the same as the one 312 that generated the previous offer or answer. 314 When SIP is used to perform an offer/answer exchange, the initial 315 mutual authentication takes place at the SIP level. Additionally, 316 SIP uses S/MIME [6] to provide an integrity-protected channel with 317 optional confidentiality for the offer/answer exchange. BFCP takes 318 advantage of this integrity-protected offer/answer exchange to 319 perform authentication. Within the offer/answer exchange, the 320 offerer and answerer exchange the fingerprints of their self-signed 321 certificates. These self-signed certificates are then used to 322 establish the TLS connection that will carry BFCP traffic between the 323 offerer and the answerer. 325 BFCP clients and floor control servers follow the rules in [10] 326 regarding certificate choice and presentation. This implies that 327 unless a 'fingerprint' attribute is included in the session 328 description, the certificate provided at the TLS-level MUST either be 329 directly signed by one of the other party's trust anchors or be 330 validated using a certification path that terminates at one of the 331 other party's trust anchors [5]. Endpoints that use the offer/answer 332 model to establish BFCP connections MUST support the 'fingerprint' 333 attribute and SHOULD include it in their session descriptions. 335 When TLS is used with TCP, once the underlying connection is 336 established, the answerer acts as the TLS server regardless of its 337 role (passive or active) in the TCP establishment procedure. 339 9. Examples 341 For the purpose of brevity, the main portion of the session 342 description is omitted in the examples, which only show 'm' lines and 343 their attributes. 345 The following is an example of an offer sent by a conference server 346 to a client. 348 m=application 50000 TCP/TLS/BFCP * 349 a=setup:passive 350 a=connection:new 351 a=fingerprint:SHA-1 \ 352 4A:AD:B9:B1:3F:82:18:3B:54:02:12:DF:3E:5D:49:6B:19:E5:7C:AB 353 a=floorctrl:s-only 354 a=confid:4321 355 a=userid:1234 356 a=floorid:1 mstrm:10 357 a=floorid:2 mstrm:11 358 m=audio 50002 RTP/AVP 0 359 a=label:10 360 m=video 50004 RTP/AVP 31 361 a=label:11 363 Note that due to RFC formatting conventions, this document splits SDP 364 across lines whose content would exceed 72 characters. A backslash 365 character marks where this line folding has taken place. This 366 backslash and its trailing CRLF and whitespace would not appear in 367 actual SDP content. 369 The following is the answer returned by the client. 371 m=application 9 TCP/TLS/BFCP * 372 a=setup:active 373 a=connection:new 374 a=fingerprint:SHA-1 \ 375 3D:B4:7B:E3:CC:FC:0D:1B:5D:31:33:9E:48:9B:67:FE:68:40:E8:21 376 a=floorctrl:c-only 377 m=audio 55000 RTP/AVP 0 378 m=video 55002 RTP/AVP 31 380 A similar example using unreliable transport and DTLS is shown below, 381 where the offer is sent from a client. 383 m=application 50000 UDP/DTLS/BFCP * 384 a=setup:actpass 385 a=fingerprint:SHA-1 \ 386 4A:AD:B9:B1:3F:82:18:3B:54:02:12:DF:3E:5D:49:6B:19:E5:7C:AB 387 a=floorctrl:c-only, s-only 388 a=confid:4321 389 a=userid:1234 390 a=floorid:1 mstrm:10 391 a=floorid:2 mstrm:11 392 m=audio 50002 RTP/AVP 0 393 a=label:10 394 m=video 50004 RTP/AVP 31 395 a=label:11 397 The following is the answer returned by the server. 399 m=application 9 UDP/DTLS/BFCP * 400 a=setup:active 401 a=fingerprint:SHA-1 \ 402 3D:B4:7B:E3:CC:FC:0D:1B:5D:31:33:9E:48:9B:67:FE:68:40:E8:21 403 a=floorctrl:s-only 404 a=confid:4321 405 a=userid:1234 406 a=floorid:1 mstrm:10 407 a=floorid:2 mstrm:11 408 m=audio 55000 RTP/AVP 0 409 m=video 55002 RTP/AVP 31 411 10. Security Considerations 413 The BFCP [8], SDP [11], and offer/answer [4] specifications discuss 414 security issues related to BFCP, SDP, and offer/answer, respectively. 415 In addition, [7] and [10] discuss security issues related to the 416 establishment of TCP and TLS connections using an offer/answer model. 417 Furthermore, when using DTLS over UDP, considerations for its use 418 with RTP and RTCP are presented in [13]. The requirements for the 419 offer/answer exchange, as listed in Section 5 of that document, MUST 420 be followed. 422 BFCP assumes that an initial integrity-protected channel is used to 423 exchange self-signed certificates between a client and the floor 424 control server. For session descriptions carried in SIP [3], S/MIME 425 [6] is the natural choice to provide such a channel. 427 11. IANA Considerations 429 [Editorial note: The changes in Section 11.1 instruct the IANA to 430 register the two new values UDP/BFCP and UDP/TLS/BFCP for the SDP 431 'proto' field, the rest is unchanged from [14].] 433 11.1. Registration of SDP 'proto' Values 435 The IANA has registered the following values for the SDP 'proto' 436 field under the Session Description Protocol (SDP) Parameters 437 registry: 439 +--------------+------------+ 440 | Value | Reference | 441 +--------------+------------+ 442 | TCP/BFCP | [RFC XXXX] | 443 | TCP/TLS/BFCP | [RFC XXXX] | 444 | UDP/BFCP | [RFC XXXX] | 445 | UDP/TLS/BFCP | [RFC XXXX] | 446 +--------------+------------+ 448 Table 2: Values for the SDP 'proto' field 450 11.2. Registration of the SDP 'floorctrl' Attribute 452 The IANA has registered the following SDP att-field under the Session 453 Description Protocol (SDP) Parameters registry: 455 Contact name: Gonzalo.Camarillo@ericsson.com 457 Attribute name: floorctrl 459 Long-form attribute name: Floor Control 461 Type of attribute: Media level 463 Subject to charset: No 465 Purpose of attribute: The 'floorctrl' attribute is used to perform 466 floor control server determination. 468 Allowed attribute values: 1*("c-only" / "s-only" / "c-s") 470 11.3. Registration of the SDP 'confid' Attribute 472 The IANA has registered the following SDP att-field under the Session 473 Description Protocol (SDP) Parameters registry: 475 Contact name: Gonzalo.Camarillo@ericsson.com 477 Attribute name: confid 479 Long-form attribute name: Conference Identifier 481 Type of attribute: Media level 483 Subject to charset: No 485 Purpose of attribute: The 'confid' attribute carries the integer 486 representation of a Conference ID. 488 Allowed attribute values: A token 490 11.4. Registration of the SDP 'userid' Attribute 492 The IANA has registered the following SDP att-field under the Session 493 Description Protocol (SDP) Parameters registry: 495 Contact name: Gonzalo.Camarillo@ericsson.com 497 Attribute name: userid 499 Long-form attribute name: User Identifier 500 Type of attribute: Media level 502 Subject to charset: No 504 Purpose of attribute: The 'userid' attribute carries the integer 505 representation of a User ID. 507 Allowed attribute values: A token 509 11.5. Registration of the SDP 'floorid' Attribute 511 The IANA has registered the following SDP att-field under the Session 512 Description Protocol (SDP) Parameters registry: 514 Contact name: Gonzalo.Camarillo@ericsson.com 516 Attribute name: floorid 518 Long-form attribute name: Floor Identifier 520 Type of attribute: Media level 522 Subject to charset: No 524 Purpose of attribute: The 'floorid' attribute associates a floor 525 with one or more media streams. 527 Allowed attribute values: Tokens 529 12. Changes from RFC 4583 531 Following is the list of technical changes and other fixes from [15]. 533 Main purpose of this work was to add signaling support necessary to 534 support BFCP over unreliable transport, as described in [8], 535 resulting in the following changes: 537 Fields in the 'm' Line (Section 3): 538 The section is re-written to remove reference to the 539 exclusivity of TCP as a transport for BFCP streams. The 540 transport field values UDP/BFCP and UDP/TLS/BFCP added. 542 Authentication (Section 8): 543 In last paragraph, made clear that a TCP connection was 544 described. 546 Security Considerations (Section 10): 547 For the DTLS over UDP case, mention existing considerations and 548 requirements for the offer/answer exchange in [13]. 550 Registration of SDP 'proto' Values (Section 11.1): 551 Register the two new values UDP/BFCP and UDP/TLS/BFCP in the 552 SDP parameters registry. 554 The clarification and bug fixes: 556 Errata ID: 712 (Section 4 and Section 6): 557 Language clarification. Don't use terms like an SDP attribute is 558 "used in an 'm' line", instead make clear that the attribute is a 559 media-level attribute. 561 Fix typo in example (Section 9): 562 Do not use 'm-stream' in the SDP example, use the correct 'mstrm' 563 as specified in Section 9. Recommend interpreting 'm-stream' if 564 it is received, since it is present in some implementations. 566 13. Acknowledgements 568 Joerg Ott, Keith Drage, Alan Johnston, Eric Rescorla, Roni Even, and 569 Oscar Novo provided useful ideas for the original [15]. The authors 570 also acknowledge contributions to the revision of BFCP for use over 571 an unreliable transport from Geir Arne Sandbakken, Charles Eckel, 572 Eoin McLeod and Mark Thompson. 574 14. Normative References 576 [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement 577 Levels", BCP 14, RFC 2119, March 1997. 579 [2] Crocker, D. and P. Overell, "Augmented BNF for Syntax 580 Specifications: ABNF", STD 68, RFC 5234, January 2008. 582 [3] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., 583 Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP: 584 Session Initiation Protocol", RFC 3261, June 2002. 586 [4] Rosenberg, J. and H. Schulzrinne, "An Offer/Answer Model with 587 Session Description Protocol (SDP)", RFC 3264, June 2002. 589 [5] Cooper, D., Santesson, S., Farrell, S., Boeyen, S., Housley, 590 R., and W. Polk, "Internet X.509 Public Key Infrastructure 591 Certificate and Certificate Revocation List (CRL) Profile", 592 RFC 5280, May 2008. 594 [6] Ramsdell, B. and S. Turner, "Secure/Multipurpose Internet Mail 595 Extensions (S/MIME) Version 3.2 Certificate Handling", 596 RFC 5750, January 2010. 598 [7] Yon, D. and G. Camarillo, "TCP-Based Media Transport in the 599 Session Description Protocol (SDP)", RFC 4145, September 2005. 601 [8] Camarillo, G., Drage, K., Kristensen, T., Ed., Ott, J., and C. 602 Eckel, "The Binary Floor Control Protocol (BFCP)", 603 draft-ietf-bfcpbis-rfc4582bis-04 (work in progress), July 2012. 605 [9] Levin, O. and G. Camarillo, "The Session Description Protocol 606 (SDP) Label Attribute", RFC 4574, August 2006. 608 [10] Lennox, J., "Connection-Oriented Media Transport over the 609 Transport Layer Security (TLS) Protocol in the Session 610 Description Protocol (SDP)", RFC 4572, July 2006. 612 [11] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session 613 Description Protocol", RFC 4566, July 2006. 615 [12] Rescorla, E. and N. Modadugu, "Datagram Transport Layer 616 Security Version 1.2", RFC 6347, January 2012. 618 [13] Fischl, J., Tschofenig, H., and E. Rescorla, "Framework for 619 Establishing a Secure Real-time Transport Protocol (SRTP) 620 Security Context Using Datagram Transport Layer Security 621 (DTLS)", RFC 5763, May 2010. 623 [14] Camarillo, G., Ott, J., and K. Drage, "The Binary Floor Control 624 Protocol (BFCP)", RFC 4582, November 2006. 626 [15] Camarillo, G., "Session Description Protocol (SDP) Format for 627 Binary Floor Control Protocol (BFCP) Streams", RFC 4583, 628 November 2006. 630 Authors' Addresses 632 Gonzalo Camarillo 633 Ericsson 634 Hirsalantie 11 635 Jorvas 02420 636 Finland 638 Email: Gonzalo.Camarillo@ericsson.com 640 Tom Kristensen (editor) 641 Cisco 642 Philip Pedersens vei 22 643 N-1366 Lysaker 644 Norway 646 Email: tomkrist@cisco.com, tomkri@ifi.uio.no