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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 CCAMP Working Group S. Belotti 3 Internet-Draft P. Grandi 4 Intended status: Informational Alcatel-Lucent 5 Expires: April 21, 2011 D. Ceccarelli 6 D. Caviglia 7 Ericsson 8 F. Zhang 9 D. Li 10 Huawei Technologies 11 October 18, 2010 13 Information model for G.709 Optical Transport Networks (OTN) 14 draft-bccg-ccamp-otn-g709-info-model-03 16 Abstract 18 The recent revision of ITU-T recommendation G.709 [G.709-v3] has 19 introduced new fixed and flexible ODU containers in Optical Transport 20 Networks (OTNs), enabling optimized support for an increasingly 21 abundant service mix. 23 This document provides a model of information needed by the routing 24 and signaling process in OTNs to support Generalized Multiprotocol 25 Label Switching (GMPLS) control of all currently defined ODU 26 containers. 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 21, 2011. 45 Copyright Notice 47 Copyright (c) 2010 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 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4 64 2. OSPF-TE requirements overview . . . . . . . . . . . . . . . . 4 65 3. RSVP-TE requirements overview . . . . . . . . . . . . . . . . 5 66 4. G.709 Digital Layer Info Model for Routing and Signaling . . . 5 67 4.1. Tributary Slot type . . . . . . . . . . . . . . . . . . . 8 68 4.1.1. Tributary Slot type and Forwarding Adjacencies . . . . 8 69 4.2. Tributary Port Number . . . . . . . . . . . . . . . . . . 9 70 4.3. Signal type . . . . . . . . . . . . . . . . . . . . . . . 9 71 4.4. Bit rate and tolerance . . . . . . . . . . . . . . . . . . 11 72 4.5. Unreserved Resources . . . . . . . . . . . . . . . . . . . 11 73 4.6. Maximum LSP Bandwidth . . . . . . . . . . . . . . . . . . 11 74 4.7. Distinction between terminating and switching 75 capability . . . . . . . . . . . . . . . . . . . . . . . . 12 76 4.8. Priority Support . . . . . . . . . . . . . . . . . . . . . 13 77 4.9. Multi-stage multiplexing . . . . . . . . . . . . . . . . . 13 78 4.10. Generalized Label . . . . . . . . . . . . . . . . . . . . 13 79 5. Security Considerations . . . . . . . . . . . . . . . . . . . 13 80 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 81 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 13 82 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14 83 8.1. Normative References . . . . . . . . . . . . . . . . . . . 14 84 8.2. Informative References . . . . . . . . . . . . . . . . . . 14 85 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15 87 1. Introduction 89 GMPLS[RFC3945] extends MPLS to include Layer-2 Switching (L2SC), 90 Time-Division Multiplexing (e.g., SONET/SDH, PDH, and OTN), 91 Wavelength (OCh, Lambdas) Switching and Spatial Switching (e.g., 92 incoming port or fiber to outgoing port or fiber). 94 The establishment of LSPs that span only interfaces recognizing 95 packet/cell boundaries is defined in [RFC3036, RFC3212, RFC3209]. 96 [RFC3471] presents a functional description of the extensions to 97 Multi-Protocol Label Switching (MPLS) signaling required to support 98 GMPLS. ReSource reserVation Protocol-Traffic Engineering (RSVP-TE) 99 -specific formats,mechanisms and technology specific details are 100 defined in [RFC3473]. 102 From a routing perspective, Open Shortest Path First-Traffic 103 Engineering (OSPF-TE) generates Link State Advertisements (LSAs) 104 carrying application-specific information and floods them to other 105 nodes as defined in [RFC5250]. Three types of opaque LSA are 106 defined, i.e. type 9 - link-local flooding scope, type 10 - area- 107 local flooding scope, type 11 - AS flooding scope. 109 Type 10 LSAs are composed of a standard LSA header and a payload 110 including one top-level TLV and possible several nested sub-TLVs. 111 [RFC3630] defines two top-level TLVs: Router Address TLV and Link 112 TLV; and nine possible sub-TLVs for the Link TLV, used to carry link 113 related TE information. The Link type sub-TLVs are enhanced by 114 [RFC4203] in order to support GMPLS networks and related specific 115 link information. In GMPLS networks each node generates TE LSAs to 116 advertise its TE information and capabilities (link-specific or node- 117 specific)through the network. The TE information carried in the LSAs 118 are collected by the other nodes of the network and stored into their 119 local Traffic Engineering Databases (TED). 121 In a GMPLS enabled G.709 Optical Transport Networks (OTN), routing 122 and signaling are fundamental in order to allow automatic calculation 123 and establishment of routes for ODUk LSPs. The recent revision of 124 ITU-T Recommendation G.709 [G709-V3] has introduced new fixed and 125 flexible ODU containers that augment those specified in foundation 126 OTN. As a result, it is necessary to provide OSPF-TE and RSVP-TE 127 extensions to allow GMPLS control of all currently defined ODU 128 containers. 130 This document provides the information model needed by the routing 131 and signaling processses in OTNs to allow GMPLS control of all 132 currently defined ODU containers. 134 OSPF-TE and RSVP-tE requirements are defined in [OTN-FWK], while 135 protocol extensions are defined in [OTN-OSPF] and [OTN-RSVP]. 137 1.1. Terminology 139 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 140 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 141 document are to be interpreted as described in [RFC2119]. 143 2. OSPF-TE requirements overview 145 [OTN-FWK] provides a set of functional routing requirements 146 summarized below : 148 - Support for link multiplexing capability advertisement: The 149 routing protocol has to be able to carry information regarding the 150 capability of an OTU link to support different type of ODUs 152 - Support for TS granularity advertisement: Each ODUj can be 153 multiplexed into an OTUk using different TS granularities. For 154 example, ODU1 can be multiplexed into ODU2 with either 2.5Gbps TS 155 granularity or 1.25G TS granularity. The routing protocol should 156 be capable of carrying the TS granularity supported by the ODU 157 interface. 159 - Support of any ODUk and ODUflex: The routing protocol must be 160 capable of carrying the required link bandwidth information for 161 performing accurate route computation for any of the fixed rate 162 ODUs as well as ODUflex. 164 - Support for differentiation between switching and terminating 165 capacity 167 - Support different priorities for resource reservation. How many 168 priorities levels should be supported depends on operator 169 policies. Therefore, the routing protocol should be capable of 170 supporting either no priorities or up to 8 priority levels as 171 defined in [RFC4202]. 173 - Support link bundling either at the same line rate or different 174 line rates (e.g. 40G and 10G). Bundling links at different rates 175 makes the control plane more scalable and permits better 176 networking flexibility. 178 3. RSVP-TE requirements overview 180 [OTN-FWK] also provides a set of functional signaling requirements 181 summarized below : 183 - Support for LSP setup of new ODUk/ODUflex containers with 184 related mapping and multiplexing capabilities 186 - Support for LSP setup using different Tributary Slot granularity 188 - Support for Tributary Port Number allocation and negoziation 190 - Support for constraint signaling 192 4. G.709 Digital Layer Info Model for Routing and Signaling 194 The digital OTN layered structure is comprised of digital path layer 195 networks (ODU) and digital section layer networks (OTU). An OTU 196 section layer supports one ODU path layer as client and provides 197 monitoring capability for the OCh. An ODU path layer may transport a 198 heterogeneous assembly of ODU clients. Some types of ODUs (i.e., 199 ODU1, ODU2, ODU3, ODU4) may assume either a client or server role 200 within the context of a particular networking domain. ITU-T G.872 201 amendment 2 provides two tables defining mapping and multiplexing 202 capabilities of OTNs, which are reproduced below. 204 +--------------------+--------------------+ 205 | ODU client | OTU server | 206 +--------------------+--------------------+ 207 | ODU 0 | - | 208 +--------------------+--------------------+ 209 | ODU 1 | OTU 1 | 210 +--------------------+--------------------+ 211 | ODU 2 | OTU 2 | 212 +--------------------+--------------------+ 213 | ODU 2e | - | 214 +--------------------+--------------------+ 215 | ODU 3 | OTU 3 | 216 +--------------------+--------------------+ 217 | ODU 4 | OTU 4 | 218 +--------------------+--------------------+ 219 | ODU flex | - | 220 +--------------------+--------------------+ 222 Figure 1: OTN mapping capability 224 +=================================+=========================+ 225 | ODU client | ODU server | 226 +---------------------------------+-------------------------+ 227 | 1,25 Gbps client | | 228 +---------------------------------+ ODU 0 | 229 | - | | 230 +=================================+=========================+ 231 | 2,5 Gbps client | | 232 +---------------------------------+ ODU 1 | 233 | ODU 0 | | 234 +=================================+=========================+ 235 | 10 Gbps client | | 236 +---------------------------------+ ODU 2 | 237 | ODU0,ODU1,ODUflex | | 238 +=================================+=========================+ 239 | 10,3125 Gbps client | | 240 +---------------------------------+ ODU 2e | 241 | - | | 242 +=================================+=========================+ 243 | 40 Gbps client | | 244 +---------------------------------+ ODU 3 | 245 | ODU0,ODU1,ODU2,ODU2e,ODUflex | | 246 +=================================+=========================+ 247 | 100 Gbps client | | 248 +---------------------------------+ ODU 4 | 249 |ODU0,ODU1,ODU2,ODU2e,ODU3,ODUflex| | 250 +=================================+=========================+ 252 Figure 2: OTN multiplexing capability 254 How an ODUk connection service is transported within an operator 255 network is governed by operator policy. For example, the ODUk 256 connection service might be transported over an ODUk path over an 257 OTUk section, with the path and section being at the same rate as 258 that of the connection service (see Table 1). In this case, an 259 entire lambda of capacity is consumed in transporting the ODUk 260 connection service. On the other hand, the operator might exploit 261 different multiplexing capabilities in the network to improve 262 infrastructure efficiencies within any given networking domain. In 263 this case, ODUk multiplexing may be performed prior to transport over 264 various rate ODU servers (as per Table 2) over associated OTU 265 sections. 267 From the perspective of multiplexing relationships, a given ODUk may 268 play different roles as it traverses various networking domains. 270 As detailed in [OTN-FWK], client ODUk connection services can be 271 transported over: 273 o Case A) one or more wavelength sub-networks connected by optical 274 links or 276 o Case B) one or more ODU links (having sub-lambda and/or lambda 277 bandwidth granularity) 279 o Case C) a mix of ODU links and wavelength sub-networks. 281 This document considers the TE information needed for ODU path 282 computation and parameters needed to be signaled for LSP setup. 284 The following sections list and analyze each type of data that needs 285 to be advertised and signaled in order to support path computation 286 and LSP setup. 288 4.1. Tributary Slot type 290 ITU-T recommendations define two types of TS but each link can only 291 support a single type at a given time. The rules to be followed when 292 selecting the TS to be used are: 294 - If both ends of a link can support both 2.5Gbps TS and 1.25Gbps 295 TS, then the link will work with 1.25Gbps TS. 297 - If one end can support the 1.25Gbps TS, and another end the 298 2.5Gbps TS, the link will work with 2.5Gbps TS. 300 In case the bandwidth accounting is provided in number of TSs, the 301 type of TS is needed to perform correct routing operations. 302 Currently such information is not provided by the routing protocol 303 and not taken into account during LSP signaling. 305 The tributary slot type information is one of the parameters needed 306 to correctly configure physical interfaces, therefore it has to be 307 signaled via RSVP-TE. 309 4.1.1. Tributary Slot type and Forwarding Adjacencies 311 TS granularity is a TE link type information and is defined as 312 depicted in Section 4.1. The TS granularity information has to be 313 advertised when setting up a Forwarding Adjacency (FA) by end points 314 of the FA. With reference to Figure3 the FA between node A and D has 315 to be advertised by both nodes A and D. The nodes A and D have to be 316 aware of the TS granularity associated to the interfaces A1 and D1 in 317 order to produce consistent advertisement. 319 In line with what described in [HIER-BIS] RSVP-TE is in charge of 320 providing all the information needed to allow automatic FA setup. As 321 a consequence the TS granularity information will have to be signaled 322 via RSVP-TE. 324 forwarding adjacency 325 ________________________________________ 326 | | 327 +--------+ +--------+ +--------+ +--------+ 328 | | | | | | | | 329 | Node |A1 B1| Node |B2 C1| Node |C2 D1| Node | 330 | A +------+ B +------+ C +------+ D | 331 | | otu3 | | otu3 | | otu3 | | 332 +--------+ 1.25 +--------+ 1.25 +--------+ 2.5 +--------+ 334 Figure 3: FA in mixed TS granularity 336 4.2. Tributary Port Number 338 [RFC4328] supports only the deprecated auto-MSI mode which assumes 339 that the Tributary Port Number is automatically assigned in the 340 transmit direction and not checked in the receive direction. 342 As described in [G709-V3] and [G798-V3], the OPUk overhead in an OTUk 343 frame contains n (n = the total number of TSs of the ODUk) MSI 344 (Multiplex Structure Identifier) bytes (in the form of multi-frame), 345 each of which is used to indicate the association between tributary 346 port number and tributary slot of the ODUk. 348 The association between TPN and TS has to be configured by the 349 control plane and checked by the data plane on each side of the link. 350 (Please refer to [OTN-FWK] for further details). As a consequence, 351 the RSVP-TE signaling needs to be extended to support the TPN 352 assignment function. 354 4.3. Signal type 356 From a routing perspetive, [RFC 4203] allows advertising foundation 357 G.709 (single TS type) without the capability of providing precise 358 information about bandwidth specific allocation. For example, in 359 case of link bundling, dividing the unreserved bandwidth by the MAX 360 LSP bandwidth it is not possible to know the exact number of LSPs at 361 MAX LSP bandwidth size that can be set up. (see example fig. 3) 363 The lack of spatial allocation heavily impacts the restoration 364 process, because the lack of information of free resources highly 365 increases the number of crank-backs affecting network convergence 366 time. 368 Moreover actual tools provided by OSPF-TE only allow advertising 369 signal types with fixed bandwidth and implicit hierarchy (e.g. SDH/ 370 SONET networks) or variable bandwidth with no hierarchy (e.g. packet 371 switching networks) but do not provide the means for advertising 372 networks with mixed approach (e.g. ODUflex CBR and ODUflex packet). 374 For example, advertising ODU0 as MIN LSP bandwidth and ODU4 as MAX 375 LSP bandwidth it is not possible to state whether the advertised link 376 supports ODU4 and ODUflex or ODU4, ODU3, ODU2, ODU1, ODU0 and 377 ODUflex. Such ambiguity is not present in SDH networks where the 378 hierarchy is implicit and flexible containers like ODUFlex do not 379 exist. The issue could be resolved by declaring 1 ISCD for each 380 signal type actually supported by the link. 382 Supposing for example to have an equivalent ODU2 unreserved bandwidth 383 in a TE-link (with bundling capability) distributed on 4 ODU1, it 384 would be advertised via the ISCD in this way: 386 MAX LSP Bw: ODU1 388 MIN LSP Bw: ODU1 390 - Maximum Reservable Bandwidth (of the bundle) set to ODU2 392 - Unreserved Bandwidth (of the bundle) set to ODU2 394 Moreover with the current IETF solutions, ([RFC4202], [RFC4203]) as 395 soon as no bandwidth is available for a certain signal type it is not 396 advertised into the related ISCD, losing also the related capability 397 until bandwidth is freed. 399 In conclusion, the OSPF-TE extensions defined in [RFC4203] require a 400 different ISCD per signal type in order to advertise each supported 401 container. This motivates attempting to look for a more optimized 402 solution, without proliferations of the number of ISCD advertised. 403 With respect to link bundling, the utilization of the ISCD as it is, 404 would not allow precise advertising of spatial bandwidth allocation 405 information unless using only one component link per TE link. 407 On the other hand, from a singaling point of view, [RFC4328] 408 describes GMPLS signaling extensions to support the control for G.709 409 OTNs [G709-V1]. However,[RFC4328] needs to be updated because it 410 does not provide the means to signal all the new signal types and 411 related mapping and multiplexing functionalities. 413 4.4. Bit rate and tolerance 415 In the current traffic parameters signaling, bit rate and tolerance 416 are implicitly defined by the signal type. ODUflex CBR and Packet 417 can have variable bit rates and tolerances (please refer to [OTN-FWK] 418 table 2); it is thus needed to upgrade the signaling traffic 419 patameters so to specify requested bit rates and tolerance values 420 during LSP setup. 422 4.5. Unreserved Resources 424 Unreserved resources need to be advertised per priority and per 425 signal type in order to allow the correct functioning of the 426 restoration process. [RFC4203] only allows advertising unreserved 427 resources per priority, this leads not to know how many LSPs of a 428 specific signal type can be restored. As example it is possible to 429 consider the scenario depicted in the following figure. 431 +------+ component link 1 +------+ 432 | +------------------+ | 433 | | component link 2 | | 434 | N1 +------------------+ N2 | 435 | | component link 3 | | 436 | +------------------+ | 437 +------+ +---+--+ 439 Figure 4: Concurrent path computation 441 Suppose to have a TE link comprising 3 ODU3 component links with 442 32TSs available on the first one, 24TSs on the second, 24TSs on the 443 third and supporting ODU2 and ODU3 signal types. The node would 444 advertise a TE link unreserved bandwidth equal to 80 TSs and a MAX 445 LSP bandwidth equal to 32 TSs. In case of restoration the network 446 could try to restore 2 ODU3 (64TSs) in such TE-link while only a 447 single ODU3 can be set up and a crank-back would be originated. In 448 more complex network scenarios the number of crank-backs can be much 449 higher. 451 4.6. Maximum LSP Bandwidth 453 Maximum LSP bandwidth is currently advertised in the common part of 454 the ISCD and advertised per priority, while in OTN networks it is 455 only required for ODUflex advertising. This leads to a significant 456 waste of bits inside each LSA. 458 4.7. Distinction between terminating and switching capability 460 The capability advertised by an interface needs further distinction 461 in order to separate termination and switching capabilities. Due to 462 internal constraints and/or limitations, the type of signal being 463 advertised by an interface could be just switched (i.e. forwarded to 464 switching matrix without multiplexing/demultiplexing actions), just 465 terminated (demuxed) or both of them. The following figures help 466 explainig the switching and terminating capabilities. 468 MATRIX LINE INTERFACE 469 +-----------------+ +-----------------+ 470 | +-------+ | ODU2 | | 471 ----->| ODU-2 |----|----------|--------\ | 472 | +-------+ | | +----+ | 473 | | | \__/ | 474 | | | \/ | 475 | +-------+ | ODU3 | | ODU3 | 476 ----->| ODU-3 |----|----------|------\ | | 477 | +-------+ | | \ | | 478 | | | \| | 479 | | | +----+ | 480 | | | \__/ | 481 | | | \/ | 482 | | | ---------> OTU-3 483 +-----------------+ +-----------------+ 485 Figure 5: Switching and Terminating capabilities 487 The figure in the example shows a line interface able to: 489 - Multiplex an ODU2 coming from the switching matrix into and ODU3 490 and map it into an OTU3 492 - Map an ODU3 coming from the switching matrix into an OTU3 494 In this case the interface bandwidth advertised is ODU2 with 495 switching capability and ODU3 with both switching and terminating 496 capabilities. 498 This piece of information needs to be advertised together with the 499 related unreserved bandwidth and signal type. As a consequence 500 signaling must have the possibility to setup an LSP allowing the 501 local selection of resources consistent with the limitations 502 considered during the path computation. 504 4.8. Priority Support 506 The IETF foresees that up to eight priorities must be supported and 507 that all of them have to be advertised independently on the number of 508 priorities supported by the implementation. Considering that the 509 advertisement of all the different supported signal types will 510 originate large LSAs, it is advised to advertise only the information 511 related to the really supported priorities. 513 4.9. Multi-stage multiplexing 515 With reference to the [OTN-FWK], introduction of multi-stage 516 multiplexing implies the advertisement of cascaded adaptation 517 capabilities together with the matrix access constraints. The 518 structure defined by IETF for the advertisement of adaptation 519 capabilities is ISCD/IACD as in [RFC4202] and [RFC5339]. 520 Modifications to ISCD/IACD , if needed, are FFS. 522 4.10. Generalized Label 524 The ODUk label format defined in [RFC4328] could be updated to 525 support new signal types defined in [G709-V3] but would hardly be 526 further enhanced to support possible new signal types. 528 Furthermore such label format may have scalability issues due to the 529 high number of labels needed when signaling large LSPs. For example, 530 when an ODU3 is mapped into an ODU4 with 1.25G tributary slots, it 531 would require the utilization of thirty-one labels (31*4*8=992 bits) 532 to be allocated while an ODUflex into an ODU4 may need up to eighty 533 labels (80*4*8=2560 bits). 535 A new flexible and scalable ODUk label format needs to be defined. 537 5. Security Considerations 539 TBD 541 6. IANA Considerations 543 TBD 545 7. Acknowledgements 547 The authors would like to thank Eve Varma and Sergio Lanzone for 548 their precious collaboration and review. 550 8. References 552 8.1. Normative References 554 [HIER-BIS] 555 K.Shiomoto, A.Farrel, "Procedure for Dynamically Signaled 556 Hierarchical Label Switched Paths", work in 557 progress draft-ietf-lsp-hierarchy-bis-08, February 2010. 559 [OTN-OSPF] 560 D.Ceccarelli,D.Caviglia,F.Zhang,D.Li,Y.Xu,P.Grandi,S.Belot 561 ti, "Traffic Engineering Extensions to OSPF for 562 Generalized MPLS (GMPLS) Control of Evolutive G.709 OTN 563 Networks", work in 564 progress draft-ceccarelli-ccamp-gmpls-ospf-g709-03, August 565 2010. 567 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 568 Requirement Levels", BCP 14, RFC 2119, March 1997. 570 [RFC3630] Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering 571 (TE) Extensions to OSPF Version 2", RFC 3630, 572 September 2003. 574 [RFC4202] Kompella, K. and Y. Rekhter, "Routing Extensions in 575 Support of Generalized Multi-Protocol Label Switching 576 (GMPLS)", RFC 4202, October 2005. 578 [RFC4203] Kompella, K. and Y. Rekhter, "OSPF Extensions in Support 579 of Generalized Multi-Protocol Label Switching (GMPLS)", 580 RFC 4203, October 2005. 582 [RFC4328] Papadimitriou, D., "Generalized Multi-Protocol Label 583 Switching (GMPLS) Signaling Extensions for G.709 Optical 584 Transport Networks Control", RFC 4328, January 2006. 586 [RFC5250] Berger, L., Bryskin, I., Zinin, A., and R. Coltun, "The 587 OSPF Opaque LSA Option", RFC 5250, July 2008. 589 [RFC5339] Le Roux, JL. and D. Papadimitriou, "Evaluation of Existing 590 GMPLS Protocols against Multi-Layer and Multi-Region 591 Networks (MLN/MRN)", RFC 5339, September 2008. 593 8.2. Informative References 595 [G.709-v1] 596 ITU-T, "Interface for the Optical Transport Network 597 (OTN)", G.709 Recommendation (and Amendment 1), 598 February 2001. 600 [G.709-v2] 601 ITU-T, "Interface for the Optical Transport Network 602 (OTN)", G.709 Recommendation (and Amendment 1), 603 March 2003. 605 [G.709-v3] 606 ITU-T, "Rec G.709, version 3", approved by ITU-T on 607 December 2009. 609 [G.872-am2] 610 ITU-T, "Amendment 2 of G.872 Architecture of optical 611 transport networks for consent", consented by ITU-T on 612 June 2010. 614 [OTN-FWK] F.Zhang, D.Li, H.Li, S.Belotti, "Framework for GMPLS and 615 PCE Control of G.709 Optical Transport Networks", work in 616 progress draft-ietf-ccamp-gmpls-g709-framework-00, April 617 2010. 619 Authors' Addresses 621 Sergio Belotti 622 Alcatel-Lucent 623 Via Trento, 30 624 Vimercate 625 Italy 627 Email: sergio.belotti@alcatel-lucent.com 629 Pietro Vittorio Grandi 630 Alcatel-Lucent 631 Via Trento, 30 632 Vimercate 633 Italy 635 Email: pietro_vittorio.grandi@alcatel-lucent.com 636 Daniele Ceccarelli 637 Ericsson 638 Via A. Negrone 1/A 639 Genova - Sestri Ponente 640 Italy 642 Email: daniele.ceccarelli@ericsson.com 644 Diego Caviglia 645 Ericsson 646 Via A. Negrone 1/A 647 Genova - Sestri Ponente 648 Italy 650 Email: diego.caviglia@ericsson.com 652 Fatai Zhang 653 Huawei Technologies 654 F3-5-B R&D Center, Huawei Base 655 Shenzhen 518129 P.R.China Bantian, Longgang District 656 Phone: +86-755-28972912 658 Email: zhangfatai@huawei.com 660 Dan Li 661 Huawei Technologies 662 F3-5-B R&D Center, Huawei Base 663 Shenzhen 518129 P.R.China Bantian, Longgang District 664 Phone: +86-755-28973237 666 Email: danli@huawei.com