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'1') (Obsoleted by RFC 8077) ** Obsolete normative reference: RFC 4379 (ref. '10') (Obsoleted by RFC 8029) == Outdated reference: A later version (-07) exists of draft-ietf-pwe3-vccv-bfd-06 == Outdated reference: A later version (-06) exists of draft-ietf-mpls-tp-oam-requirements-02 == Outdated reference: A later version (-10) exists of draft-ietf-mpls-tp-requirements-09 == Outdated reference: A later version (-12) exists of draft-ietf-mpls-tp-framework-02 Summary: 5 errors (**), 0 flaws (~~), 14 warnings (==), 3 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 MPLS Working Group M. Bocci 3 Internet-Draft Alcatel-Lucent 4 Intended status: Standards Track G. Swallow 5 Expires: January 14, 2010 Cisco 6 July 13, 2009 8 MPLS-TP Identifiers 9 draft-swallow-mpls-tp-identifiers-01 11 Status of this Memo 13 This Internet-Draft is submitted to IETF in full conformance with the 14 provisions of BCP 78 and BCP 79. 16 Internet-Drafts are working documents of the Internet Engineering 17 Task Force (IETF), its areas, and its working groups. Note that 18 other groups may also distribute working documents as Internet- 19 Drafts. 21 Internet-Drafts are draft documents valid for a maximum of six months 22 and may be updated, replaced, or obsoleted by other documents at any 23 time. It is inappropriate to use Internet-Drafts as reference 24 material or to cite them other than as "work in progress." 26 The list of current Internet-Drafts can be accessed at 27 http://www.ietf.org/ietf/1id-abstracts.txt. 29 The list of Internet-Draft Shadow Directories can be accessed at 30 http://www.ietf.org/shadow.html. 32 This Internet-Draft will expire on January 14, 2010. 34 Copyright Notice 36 Copyright (c) 2009 IETF Trust and the persons identified as the 37 document authors. All rights reserved. 39 This document is subject to BCP 78 and the IETF Trust's Legal 40 Provisions Relating to IETF Documents in effect on the date of 41 publication of this document (http://trustee.ietf.org/license-info). 42 Please review these documents carefully, as they describe your rights 43 and restrictions with respect to this document. 45 Abstract 47 This document specifies identifiers for MPLS-TP objects. Included 48 are identifiers conformant to existing ITU conventions and 49 identifiers which are compatible with existing IP, MPLS, GMPLS, and 50 Pseudowire definitions. 52 Table of Contents 54 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 55 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 56 2. Named Entities . . . . . . . . . . . . . . . . . . . . . . . . 4 57 3. Uniquely Identifying an Operator . . . . . . . . . . . . . . . 5 58 3.1. The Global ID . . . . . . . . . . . . . . . . . . . . . . 5 59 3.2. ITU Carrier Code . . . . . . . . . . . . . . . . . . . . . 5 60 4. Node and Interface Identifiers . . . . . . . . . . . . . . . . 6 61 5. Path Identifiers . . . . . . . . . . . . . . . . . . . . . . . 6 62 5.1. MPLS-TP LSP Identifiers . . . . . . . . . . . . . . . . . 7 63 5.2. Pseudowire Identifiers . . . . . . . . . . . . . . . . . . 8 64 6. Maintenance Identifiers . . . . . . . . . . . . . . . . . . . 8 65 6.1. Maintenance Entity Identifiers . . . . . . . . . . . . . . 8 66 6.1.1. IP Compatible ME-IDs . . . . . . . . . . . . . . . . . 9 67 6.1.2. ICC based ME-IDs . . . . . . . . . . . . . . . . . . . 9 68 6.2. Maintenance Points . . . . . . . . . . . . . . . . . . . . 9 69 6.3. MEP_IDs for MPLS-TP LSPs and Tunnels . . . . . . . . . . . 9 70 6.4. MEP_IDs for Pseudowires . . . . . . . . . . . . . . . . . 10 71 6.5. Maintenance Intermediate Point Identifiers . . . . . . . . 10 72 7. Open issues . . . . . . . . . . . . . . . . . . . . . . . . . 10 73 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 12 74 8.1. Normative References . . . . . . . . . . . . . . . . . . . 12 75 8.2. Informative References . . . . . . . . . . . . . . . . . . 13 76 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 13 78 1. Introduction 80 This document specifies identifiers to be used in within the 81 Transport Profile of Multiprotocol Label Switching (MPLS-TP). where 82 compatibility with existing MPLS control plane conventions are 83 necessary. The MPLS-TP requirements [13] require that the elements 84 and objects in an MPLS-TP environment are able to be configured and 85 managed without a control plane. In such an environment many 86 conventions for defining identifiers are possible. In particular, 87 identifiers conformat to existing ITU conventions are defined. It is 88 also anticipated that operational environments where MPLS-TP objects, 89 e.g. Label Switched Paths (LSPs) and Pseudowires (PWs) will be 90 signaled via existing protocols such as the Label Distribution 91 Protocol (RFC 4447) [1] and the Resource Reservation Protocol as it 92 is applied to Generalized Multi-protocol Label Switching (RFCs 3471 & 93 3473) [2][3] (GMPLS). This document defines a set of identifiers for 94 MPLS-TP which are both compatible with those protocols and applicable 95 to MPLS-TP management and OAM functions. 97 1.1. Terminology 99 AII: Attachment Interface Identifier 101 ASN: Autonomous System Number 103 FEC: Forwarding Equivalence Class 105 GMPLS: Generalised Multi-Protocol Label Switching 107 ICC: ITU Carrier Code 109 LSP: Label Switched Path 111 LSR: Label Switching Router 113 ME: Maintenance Entity 115 MEP: Maintenance End Point 117 MIP: Maintenance Intermediate Point 119 MPLS: Multi-Protocol Label Switching 121 OAM: Operations, Administration and Maintenance 123 P2MP: Point to Multi-Point 125 P2P: Point to Point 126 PSC: Protection State Coordination 128 PW: Pseudowire 130 RSVP: Resource Reservation Protocol 132 RSVP-TE: RSVP Traffic Engineering 134 S-PE: Switching Provider Edge 136 T-PE: Terminating Provider Edge 138 Requirements Language 140 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 141 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 142 document are to be interpreted as described in RFC 2119 [4]. 144 2. Named Entities 146 In order to configure, operate and manage a transport network based 147 on the MPLS Transport Profile, a number of entities require 148 identification. Identifiers for the follow entities are defined in 149 this document: 151 o Operator 153 * ICC 155 * Global-ID 157 o LSR 159 o LSP 161 o PW 163 o Interface 165 o MEG 167 o MEP 169 o MIP 171 o Tunnel 172 Note that we have borrowed the term tunnel from RSVP-TE (RFC 3209) 173 [5] where it is used to describe an entity that provides an LSP 174 connection between a source and destination LSR which in turn is 175 instantiated by one or more LSPs, where the additional LSPs are used 176 for protection or re-grooming of the tunnel. 178 3. Uniquely Identifying an Operator 180 Two forms of identification are defined, one that is compatible with 181 IP operational practice called a Global_ID and one compatible with 182 ITU practice, the ICC. An Operator MAY be identified either by its 183 Global_ID or by its ICC. 185 3.1. The Global ID 187 RFC 5003 [6] defines a globally unique Attachment Interface 188 Identifier (AII). That AII is composed of three parts, a Global ID 189 which uniquely identifies a operator, a prefix, and finally and 190 attachment circuit identifier. We have chosen to use that Global ID 191 for MPLS-TP. Quoting from RFC 5003, section 3.2, "The global ID can 192 contain the 2-octet or 4-octet value of the operator's Autonomous 193 System Number (ASN). It is expected that the global ID will be 194 derived from the globally unique ASN of the autonomous system hosting 195 the PEs containing the actual AIIs. The presence of a global ID 196 based on the operator's ASN ensures that the AII will be globally 197 unique." 199 When the Global_ID is derived from a 2-octet AS number, the two high- 200 order octets of this 4-octet identifier MUST be set to zero. 202 Note that this Global_ID is used solely to provide a globally unique 203 context for other MPLS-TP identifiers. It has nothing to do with the 204 use of the ASN in protocols such as BGP. 206 3.2. ITU Carrier Code 208 M.1400 defines the ITU Carrier Code (ICC) assigned to a network 209 operator/service provider and maintained by the ITU-T 210 Telecommunication Standardization Bureau (TSB): www.itu.int/ITU-T/ 211 inr/icc/index.html. 213 ICCs can be assigned both to ITU-T and non-ITU-T members and the 214 referenced local ICC website may containu ICCs of operators of both 215 kinds. 217 The ICC is a string of one to six characters, each character being 218 either alphabetic (i.e. A-Z) or numeric (i.e. 0-9) characters. 220 Alphabetic characters in the ICC SHOULD be represented with upper 221 case letters. 223 4. Node and Interface Identifiers 225 An LSR requires identification of the node itself and of its 226 interfaces. We call the identifier associated with a node a Node 227 Identifier (Node_ID). Within the context of a particular node, we 228 call the identifier associated with an interface an Logical Interface 229 Handle or LIH. The combination of Node_ID::LIH we call an Network 230 Interface ID or Network_IF_ID. 232 In existing MPLS deployments Node_IDs are IPv4 addresses. Therefore 233 we have chosen the Node_ID to be a 32-bit value assigned by the 234 operator. Where IPv4 addresses are in use the Node_ID can be 235 automatically mapped to the LSR's /32 IPv4 loopback address. Note 236 that, when IP reachability is not needed, the 32-bit Node_ID is not 237 required to have any association with the IPv4 address space used in 238 the operator's IGP or BGP, other that that they be uniquely chosen 239 within the scope of that operator. 241 GMPLS signaling [2] requires interface identification. We have 242 chosen to adopt the conventions of that RFC. GMPLS allows three 243 formats for the Interface_ID. For IP numbered links, it is simply 244 the IPv4 or IPv6 address associated with the interface. The third 245 format consists of an IPv4 Address plus a 32-bit unsigned integer for 246 the specific interface. 248 For MPLS-TP, we have adopted a format consitent with the third format 249 above. In MPLS-TP, each interface is assigned a 32-bit identifier 250 which we call an LIH. The LIH MUST be unique within the context of 251 the Node_ID. We map the Node_ID to the field the field which carries 252 the IP address. That is, a Nework_IF_ID is a 64-bit identifier 253 consisting of the Node_ID followed by the LIH. The LIH in turn is a 254 32-bit unsigned integer unique to the node. 256 In situations where a Node_ID or an Network_IF_ID needs to be 257 globally unique, this is accomplished by prefixing the identifier 258 with the operator's Global_ID. The combination of Global_ID::Node_ID 259 we call an Global Node ID or Global_Node_ID. Likewise, the 260 combination of Global_ID::Node_ID::LIH we call an Global Interface ID 261 or Global_IF_ID. 263 5. Path Identifiers 264 5.1. MPLS-TP LSP Identifiers 266 [Note: See proposed changes to in the issues section] 268 GMPLS signalling [3] uses a 5-tuple to uniquely identify an LSP 269 within a operator's network. This tuple is composed of a Tunnel 270 Endpoint Address, Tunnel_ID, Extended Tunnel ID, and Tunnel Sender 271 Address and LSP_ID. For MPLS-TP we have chosen a 4-tuple to uniquely 272 identify a MPLS-TP LSP. This is composed of a Source Node_ID, 273 Destination Node_ID, Tunnel_Nbr, and LSP_Nbr. The terms Source and 274 Destination in this context are used relative to the direction of the 275 signalling. Note that the Tunnel_ID MUST be unique within the 276 context of the source. 278 In situations where a mapping to the GMPLS 5-tuple is required, the 279 following mapping is used. 281 o Tunnel Endpoint Address = Destination Node_ID 283 o Tunnel_ID = Tunnel_Nbr 285 o Extended Tunnel_ID = Source Node_ID 287 o Tunnel Sender Address = Source Node_ID 289 o LSP_ID = LSP_Nbr 291 A important construct within MPLS_TP is a connection which is 292 provided across a working and a protect LSP. Note that RFC 4872 [7], 293 "RSVP-TE Extensions for E2E GMPLS Recovery", requires that the 294 working and protect LSP have the same identification except for the 295 LSP_ID, which must be unique. Within this document we will use the 296 term Tunnel for the connection provided by the working and protect 297 LSPs. 299 Thus, a Protected MPLS-TP LSP within a single operator is uniquely 300 identified by the 3-tuple, Source Node_ID, Destination Node_ID and 301 Tunnel_Nbr. Similarly, an MPLS-TP LSP is uniquely identified by the 302 4-tuple, Source Node_ID, Destination Node_ID, Tunnel_Nbr and LSP_Nbr. 304 In situations where a tunnel or an LSP needs to be globally unique, 305 this is accomplished by prefixing each of the source and destination 306 Node_IDs with a operator's Global_ID. 308 When an MPLS-TP LSP is configured, it MUST be assigned a unique 309 Network_IF_ID at both the source and destination endpoints. Further 310 when a MPLS-TP Tunnel is configured, it too must be assigned a unique 311 Network_IF_ID. Thus a point-to-point tunnel with working and protect 312 LSPs will have a total of three Network_IF_IDs assigned at each of 313 the source and destination. 315 5.2. Pseudowire Identifiers 317 Pseudowire signalling (RFC 4447 [1]) defines two FECs used to signal 318 pseudowires. Of these, FEC Type 129 along with AII Type 2 as defined 319 in RFC 5003 [6] fits the identification requirements of MPLS-TP. 321 In an MPLS-TP environment, a PW is identified by a set of identifiers 322 which can be mapped directly to the elements required by FEC 129 and 323 AII Type 2. The AII is composed of three fields. These are the 324 Global_ID, the Prefix, and the AC_ID. The Global_ID used in this 325 document is identical to the Global_ID defined in RFC 5003. The 326 Node_ID is used as the Prefix. The AC_ID is as defined in RFC 5003. 328 To complete the FEC 129, all that is required is a Attachment Group 329 Identifier (AGI). That field is exactly as specified in RFC 4447. 330 FEC 129 has a notion of Source AII (SAII) and Target AII (TAII). 331 These terms are used relative to the direction of the signalling. In 332 a purely configured environment when referring to the entire PW, this 333 distinction is not critical. That is a FEC 129 of AGIa::AIIb::AIIc 334 is equivalent to AGIa::AIIc::AIIb. We note that in a signalled 335 environment, the required convention in RFC 4447 is that at a 336 particular endpoint, the AII associated with that endpoint comes 337 first. 339 6. Maintenance Identifiers 341 In MPLS-TP a Maintenance Entity (ME) represents an Entity that 342 requires management and defines a relationship between a set of 343 maintenance points. A maintenance point is either Maintenance End- 344 point (MEP) or a Maintenance Intermediate Point (MIP). This section 345 defines a means of uniquely identifying Maintenance Entities and 346 uniquely defining MEPs and MIPs within the context of a Maintenance 347 Entity. 349 6.1. Maintenance Entity Identifiers 351 Maintenance Entity Identifiers (ME-IDs) are required for MPLS-TP 352 Paths and Pseudowires. Two classes of ME-IDs are defined, one that 353 follows the IP compatible identifier defined above as well as the 354 ICC-format. 356 A Maintenance Entity and an MPLS-TP Path are closely related by 357 separate concepts. A MPLS-TP Path is a transport entity. It exists 358 with or without an associated maintenance entity, e.g. when the LSP 359 is not monitored. 361 6.1.1. IP Compatible ME-IDs 363 In order to automatically generate MEP_IDs for MPLS-TP LSPs and 364 Pseudowires we simply use the corresponding Path identifier. 365 However, when encoded in a protocol such as in a TLV, a different 366 type needs to be defined as the two identifiers are semantically 367 different. 369 6.1.2. ICC based ME-IDs 371 ME ID for MPLS-TP LSPs and Pseudowires MAY use the globally unique 372 ICC-based format. 374 In this case, the ME ID is a string of up to thirteen characters, 375 each character being either alphabetic (i.e. A-Z) or numeric (i.e. 376 0-9) characters. It consists of two subfields: the ICC (as defined 377 in section 3) followed by a unique ME ID code (UMC). 379 The UMC MUST be unique within the organization identified by the ICC. 381 Note that when encoded in a protocol such as in a TLV, a different 382 type needs to be defined for LSP and PWs as the OAM capabilities may 383 be different. 385 6.2. Maintenance Points 387 Maintenance points are uniquely associated with a maintenance entity. 388 Within the context of a ME, MEPs and MIPs must be uniquely 389 identified. This section describes how MIPs and MEPs are identified. 391 Note that depending on the requirements of a particular OAM 392 interaction, the MPLS-TP maintenance entity context may be provided 393 either explicitly using the ME-IDs described above or implicitly by 394 the label of the received OAM message. 396 6.3. MEP_IDs for MPLS-TP LSPs and Tunnels 398 [Note: See proposed changes to in the issues section] 400 In order to automatically generate MEP_IDs for MPLS-TP Tunnels and 401 LSPs, we simply use the Network_IF_ID assigned when they are 402 configured. This ensures that MEP_IDs are unique for all Tunnels and 403 LSPs within a operator. When Tunnels or LSPs cross operator 404 boundaries, these are made unique by pre-pending them with the 405 operator's Global_ID. [Question: do we want two ACH TLV formats or 406 do we just spend the extra 4 octets on all OAM] 408 6.4. MEP_IDs for Pseudowires 410 In order to automatically generate MEP_IDs for PWs, we simply use the 411 AII associated with that end of the PW. 413 6.5. Maintenance Intermediate Point Identifiers 415 At a cross connect point, in order to automatically generate MIP_IDs 416 for MPLS-TP LSPs, we simply use the MEP_IDs of the two interfaces 417 which are cross connected via the label bindings of the MPLS-TP LSP. 418 Note that although by this mapping, the MEP and the MIP will 419 syntactically identical, the semantics will be made clear by both the 420 TLV encoding and the scoping of the identifier to its MPLS-TP Path. 421 If only one MIP is configured, then the lower value MEP_ID is chosen. 422 This ensures that MIP_IDs are unique within the scope of an ME-ID 423 within a single operator. When Tunnels, LSPs or PWs cross operator 424 boundaries, MIP_IDs are made unique by pre-pending them with the 425 operator's Global_ID. [Question: do we want two formats or do we 426 just spend the extra 4+ octets on all OAM]. 428 [Note: Note - it has been proposed that when there is just one MIP to 429 use the Node-ID only - need to discuss encoding for this] 431 7. Open issues 433 1. The lack of symmetry between the configuration of the "head" and 434 "Tail" ends of an MPLS-TP LSP makes for difficulties in 435 configuration and operational intuitiveness. Further it leads to 436 interoperability issues with other possible implementations of 437 protection. Finally there are issues with odd configurations 438 with P2MP / MP2MP (2 endpoints on the same node) I've decided 439 that the tunnel ID I previously proposed really should be 440 changed. I propose to make it more like the PW-ID 442 So instead of 444 [Src-Global-ID]::Src-Node-ID::[Dst-Global-ID]:: Dst-Node- 445 ID::Tunnel-nbr 447 It would be 449 [Src-Global-ID]::Src-Node-ID::Src-Tunnel-nbr:: [Dst-Global- 450 ID]::Dst-Node-ID::Dst-Tunnel-nbr 452 Likewise the Path-ID would go from 454 [Src-Global-ID]::Src-Node-ID::[Dst-Global-ID]:: Dst-Node- 455 ID::Tunnel-nbr::LSP-nbr 457 to 459 [Src-Global-ID]::Src-Node-ID::Src-Tunnel-nbr::Src-LSP-nbr:: 460 [Dst-Global-ID]::Dst-Node-ID::Dst-Tunnel-nbr::Dst-LSP-nbr 462 I would also change the IF-IDs and MEPs to 464 Tunnel 466 [Src-Global-ID]::Src-Node-ID::Src-Tunnel-nbr 468 Path 470 [Src-Global-ID]::Src-Node-ID::Src-Tunnel-nbr::Src-LSP-nbr 472 2. Can we do away with tunnel IDs all together and just use the IDs 473 of the Working Path instead (irrespective of whether it is active 474 or not) 476 3. We have two means of identifying operators. Should either be 477 allowed in all cases or can we constain this. I.e. when there 478 are both IP compatible and ITU compatible IDs for an Object can 479 we constrain the operator ID to the corresponding format? 480 Clearly when only one identifier is defined the both must be 481 allowed. 483 4. Details on MEP and MIP identifiers need discussion. 485 5. Additional ICC identifiers for other entities may be required 487 6. Do we need IPv6 identifiers as well? 489 7. Identifiers for P2MP entities 491 8. Tandem connection Identification - the identification should be 492 exactly the same as any other MPLS-TP LSP. However, in the ACH 493 TLV draft we could have a different TLV with the same format as 494 an MPLS-TP LSP, if there are places where the distinction becomes 495 important. 497 9. Are there additional identifiers required for NMS functions? 499 8. References 500 8.1. Normative References 502 [1] Martini, L., Rosen, E., El-Aawar, N., Smith, T., and G. Heron, 503 "Pseudowire Setup and Maintenance Using the Label Distribution 504 Protocol (LDP)", RFC 4447, April 2006. 506 [2] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) 507 Signaling Functional Description", RFC 3471, January 2003. 509 [3] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) 510 Signaling Resource ReserVation Protocol-Traffic Engineering 511 (RSVP-TE) Extensions", RFC 3473, January 2003. 513 [4] Bradner, S., "Key words for use in RFCs to Indicate Requirement 514 Levels", BCP 14, RFC 2119, March 1997. 516 [5] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., and 517 G. Swallow, "RSVP-TE: Extensions to RSVP for LSP Tunnels", 518 RFC 3209, December 2001. 520 [6] Metz, C., Martini, L., Balus, F., and J. Sugimoto, "Attachment 521 Individual Identifier (AII) Types for Aggregation", RFC 5003, 522 September 2007. 524 [7] Lang, J., Rekhter, Y., and D. Papadimitriou, "RSVP-TE 525 Extensions in Support of End-to-End Generalized Multi-Protocol 526 Label Switching (GMPLS) Recovery", RFC 4872, May 2007. 528 [8] Kompella, K., Rekhter, Y., and A. Kullberg, "Signalling 529 Unnumbered Links in CR-LDP (Constraint-Routing Label 530 Distribution Protocol)", RFC 3480, February 2003. 532 [9] Kompella, K., Rekhter, Y., and L. Berger, "Link Bundling in 533 MPLS Traffic Engineering (TE)", RFC 4201, October 2005. 535 [10] Kompella, K. and G. Swallow, "Detecting Multi-Protocol Label 536 Switched (MPLS) Data Plane Failures", RFC 4379, February 2006. 538 [11] Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow, "BFD 539 For MPLS LSPs", draft-ietf-bfd-mpls-07 (work in progress), 540 June 2008. 542 [12] Nadeau, T. and C. Pignataro, "Bidirectional Forwarding 543 Detection (BFD) for the Pseudowire Virtual Circuit 544 Connectivity Verification (VCCV)", draft-ietf-pwe3-vccv-bfd-06 545 (work in progress), July 2009. 547 8.2. Informative References 549 [13] Vigoureux, M., Ward, D., and M. Betts, "Requirements for OAM in 550 MPLS Transport Networks", 551 draft-ietf-mpls-tp-oam-requirements-02 (work in progress), 552 June 2009. 554 [14] Ohta, H., "Assignment of the 'OAM Alert Label' for 555 Multiprotocol Label Switching Architecture (MPLS) Operation and 556 Maintenance (OAM) Functions", RFC 3429, November 2002. 558 [15] Niven-Jenkins, B., Brungard, D., Betts, M., Sprecher, N., and 559 S. Ueno, "MPLS-TP Requirements", 560 draft-ietf-mpls-tp-requirements-09 (work in progress), 561 June 2009. 563 [16] Bocci, M., Bryant, S., and L. Levrau, "A Framework for MPLS in 564 Transport Networks", draft-ietf-mpls-tp-framework-02 (work in 565 progress), July 2009. 567 Authors' Addresses 569 Matthew Bocci 570 Alcatel-Lucent 571 Voyager Place, Shoppenhangers Road 572 Maidenhead, Berks SL6 2PJ 573 UK 575 Email: matthew.bocci@alcatel-lucent.com 577 George Swallow 578 Cisco 580 Email: swallow@cisco.com