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Checking references for intended status: Informational ---------------------------------------------------------------------------- No issues found here. Summary: 0 errors (**), 0 flaws (~~), 1 warning (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 1 Network Working Group Fatai Zhang, Ed. 2 Internet Draft Dan Li 3 Category: Informational Huawei 4 Han Li 5 CMCC 6 S.Belotti 7 Alcatel-Lucent 8 D. Ceccarelli 9 Ericsson 10 Expires: February 2, 2014 August 2, 2013 12 Framework for GMPLS and PCE Control of 13 G.709 Optical Transport Networks 15 draft-ietf-ccamp-gmpls-g709-framework-14.txt 17 Status of this Memo 19 This Internet-Draft is submitted to IETF in full conformance with 20 the provisions of BCP 78 and BCP 79. 22 Internet-Drafts are working documents of the Internet Engineering 23 Task Force (IETF), its areas, and its working groups. Note that 24 other groups may also distribute working documents as Internet- 25 Drafts. 27 Internet-Drafts are draft documents valid for a maximum of six months 28 and may be updated, replaced, or obsoleted by other documents at any 29 time. It is inappropriate to use Internet-Drafts as reference 30 material or to cite them other than as "work in progress." 32 The list of current Internet-Drafts can be accessed at 33 http://www.ietf.org/ietf/1id-abstracts.txt. 35 The list of Internet-Draft Shadow Directories can be accessed at 36 http://www.ietf.org/shadow.html. 38 This Internet-Draft will expire on February 2, 2014. 40 Abstract 42 This document provides a framework to allow the development of 43 protocol extensions to support Generalized Multi-Protocol Label 44 Switching (GMPLS) and Path Computation Element (PCE) control of 45 Optical Transport Networks (OTN) as specified in ITU-T Recommendation 46 G.709 as published in 2012. 48 Table of Contents 50 1. Introduction .................................................. 2 51 2. Terminology ................................................... 3 52 3. G.709 Optical Transport Network ............................... 4 53 3.1. OTN Layer Network ........................................ 4 54 3.1.1. Client signal mapping ............................... 5 55 3.1.2. Multiplexing ODUj onto Links ........................ 6 56 3.1.2.1. Structure of MSI information ................... 8 57 4. Connection management in OTN .................................. 9 58 4.1. Connection management of the ODU ........................ 10 59 5. GMPLS/PCE Implications ....................................... 12 60 5.1. Implications for Label Switch Path (LSP) Hierarchy ...... 12 61 5.2. Implications for GMPLS Signaling ........................ 13 62 5.3. Implications for GMPLS Routing .......................... 15 63 5.4. Implications for Link Management Protocol ............... 17 64 5.5. Implications for Control Plane Backward Compatibility ... 18 65 5.6. Implications for Path Computation Elements .............. 19 66 5.7. Implications for Management of GMPLS Networks ........... 19 67 6. Data Plane Backward Compatibility Considerations ............. 20 68 7. Security Considerations ...................................... 20 69 8. IANA Considerations .......................................... 21 70 9. Acknowledgments .............................................. 21 71 10. References .................................................. 21 72 10.1. Normative References ................................... 21 73 10.2. Informative References ................................. 23 74 11. Authors' Addresses .......................................... 24 75 12. Contributors ................................................ 25 77 1. Introduction 79 Optical Transport Networks (OTN) has become a mainstream layer 1 80 technology for the transport network. Operators want to introduce 81 control plane capabilities based on GMPLS to OTN, to realize the 82 benefits associated with a high-function control plane (e.g., 83 improved network resiliency, resource usage efficiency, etc.). 85 GMPLS extends Multi-Protocol Label Switching (MPLS) to encompass time 86 division multiplexing (TDM) networks (e.g., Synchronous Optical 87 NETwork (SONET)/ Synchronous Digital Hierarchy (SDH), Plesiochronous 88 Digital Hierarchy (PDH), and G.709 sub-lambda), lambda switching 89 optical networks, and spatial switching (e.g., incoming port or fiber 90 to outgoing port or fiber). The GMPLS architecture is provided in 91 [RFC3945], signaling function and Resource ReserVation Protocol- 92 Traffic Engineering (RSVP-TE) extensions are described in [RFC3471] 93 and [RFC3473], routing and Open Shortest Path First (OSPF) extensions 94 are described in [RFC4202] and [RFC4203], and the Link Management 95 Protocol (LMP) is described in [RFC4204]. 97 The GMPLS signaling extensions defined in [RFC4328] provide the 98 mechanisms for basic GMPLS control of OTN based on the 2001 revision 99 of the G.709 specification. The 2012 revision of the G.709 100 specification, [G709-2012], includes new features, for example, 101 various multiplexing structures, two types of Tributary Slots (TSs) 102 (i.e., 1.25Gbps and 2.5Gbps), and extension of the Optical channel 103 Data Unit-j (ODUj) definition to include the ODUflex function. 105 This document reviews relevant aspects of OTN technology evolution 106 that affect the GMPLS control plane protocols and examines why and 107 how to update the mechanisms described in [RFC4328]. This document 108 additionally provides a framework for the GMPLS control of OTN and 109 includes a discussion of the implication for the use of the PCE 110 [RFC4655]. 112 For the purposes of the control plane the OTN can be considered as 113 being comprised of ODU and wavelength (Optical Channel (OCh)) layers. 114 This document focuses on the control of the ODU layer, with control 115 of the wavelength layer considered out of the scope. Please refer to 116 [RFC6163] for further information about the wavelength layer. 118 2. Terminology 120 OTN: Optical Transport Network 122 OPU: Optical channel Payload Unit 124 ODU: Optical channel Data Unit 126 OTU: Optical channel Transport Unit 128 OMS: Optical multiplex section 130 MSI: Multiplex Structure Identifier 132 TPN: Tributary Port Number 133 LO ODU: Lower Order ODU. The LO ODUj (j can be 0, 1, 2, 2e, 3, 4, 134 flex.) represents the container transporting a client of the OTN that 135 is either directly mapped into an OTUk (k = j) or multiplexed into a 136 server HO ODUk (k > j) container. 138 HO ODU: Higher Order ODU. The HO ODUk (k can be 1, 2, 2e, 3, 4.) 139 represents the entity transporting a multiplex of LO ODUj tributary 140 signals in its OPUk area. 142 ODUflex: Flexible ODU. A flexible ODUk can have any bit rate and a 143 bit rate tolerance of +/-100 ppm (parts per million). 145 3. G.709 Optical Transport Network 147 This section provides an informative overview of those aspects of the 148 OTN impacting control plane protocols. This overview is based on the 149 ITU-T Recommendations that contain the normative definition of the 150 OTN. Technical details regarding OTN architecture and interfaces are 151 provided in the relevant ITU-T Recommendations. 153 Specifically, [G872-2012] describes the functional architecture of 154 optical transport networks providing optical signal transmission, 155 multiplexing, routing, supervision, performance assessment, and 156 network survivability. The legacy OTN referenced by [RFC4328] defines 157 the interfaces of the optical transport network to be used within and 158 between subnetworks of the optical network. With the evolution and 159 deployment of OTN technology many new features have been specified in 160 ITU-T recommendations, including for example, new ODU0, ODU2e, ODU4 161 and ODUflex containers as described in [G709-2012]. 163 3.1. OTN Layer Network 165 The simplified signal hierarchy of OTN is shown in Figure 1, which 166 illustrates the layers that are of interest to the control plane. 167 Other layers below OCh (e.g. Optical Transmission Section (OTS)) are 168 not included in this Figure. The full signal hierarchy is provided in 169 [G709-2012]. 171 Client signal 172 | 173 ODUj 174 | 175 OTU/OCh 176 OMS 178 Figure 1 - Basic OTN signal hierarchy 180 Client signals are mapped into ODUj containers. These ODUj containers 181 are multiplexed onto the OTU/OCh. The individual OTU/OCh signals are 182 combined in the OMS using Wavelength Division Multiplexing (WDM), and 183 this aggregated signal provides the link between the nodes. 185 3.1.1. Client signal mapping 187 The client signals are mapped into a LO ODUj. The current values of j 188 defined in [G709-2012] are: 0, 1, 2, 2e, 3, 4, Flex. The approximate 189 bit rates of these signals are defined in [G709-2012] and are 190 reproduced in Tables 1 and 2. 192 Table 1 - ODU types and bit rates 193 +-----------------------+-----------------------------------+ 194 | ODU Type | ODU nominal bit rate | 195 +-----------------------+-----------------------------------+ 196 | ODU0 | 1,244,160 Kbps | 197 | ODU1 | 239/238 x 2,488,320 Kbps | 198 | ODU2 | 239/237 x 9,953,280 Kbps | 199 | ODU3 | 239/236 x 39,813,120 Kbps | 200 | ODU4 | 239/227 x 99,532,800 Kbps | 201 | ODU2e | 239/237 x 10,312,500 Kbps | 202 | | | 203 | ODUflex for | | 204 |Constant Bit Rate (CBR)| 239/238 x client signal bit rate | 205 | Client signals | | 206 | | | 207 | ODUflex for Generic | | 208 | Framing Procedure | Configured bit rate | 209 | - Framed (GFP-F) | | 210 | Mapped client signal | | 211 +-----------------------+-----------------------------------+ 213 NOTE - The nominal ODUk rates are approximately: 2,498,775.126 Kbps 214 (ODU1), 10,037,273.924 Kbps (ODU2), 40,319,218.983 Kbps (ODU3), 215 104,794,445.815 Kbps (ODU4) and 10,399,525.316 Kbps (ODU2e). 217 Table 2 - ODU types and tolerance 218 +-----------------------+-----------------------------------+ 219 | ODU Type | ODU bit-rate tolerance | 220 +-----------------------+-----------------------------------+ 221 | ODU0 | +/-20 ppm | 222 | ODU1 | +/-20 ppm | 223 | ODU2 | +/-20 ppm | 224 | ODU3 | +/-20 ppm | 225 | ODU4 | +/-20 ppm | 226 | ODU2e | +/-100 ppm | 227 | | | 228 | ODUflex for CBR | | 229 | Client signals | +/-100 ppm | 230 | | | 231 | ODUflex for GFP-F | | 232 | Mapped client signal | +/-100 ppm | 233 +-----------------------+-----------------------------------+ 235 One of two options is for mapping client signals into ODUflex 236 depending on the client signal type: 238 - Circuit clients are proportionally wrapped. Thus the bit rate is 239 defined by the client signal and the tolerance is fixed to +/-100 240 ppm. 242 - Packet clients are mapped using the Generic Framing Procedure 243 (GFP). [G709-2012] recommends that the ODUflex(GFP) will fill an 244 integral number of tributary slots of the smallest HO ODUk path 245 over which the ODUflex(GFP) may be carried, and the tolerance 246 should be +/-100 ppm. 248 Note that additional information on G.709 client mapping can be found 249 in [G7041]. 251 3.1.2. Multiplexing ODUj onto Links 253 The links between the switching nodes are provided by one or more 254 wavelengths. Each wavelength carries one OCh, which carries one OTU, 255 which carries one ODU. Since all of these signals have a 1:1:1 256 relationship, we only refer to the OTU for clarity. The ODUjs are 257 mapped into the TSs (Tributary Slots) of the OPUk. Note that in the 258 case where j=k the ODUj is mapped into the OTU/OCh without 259 multiplexing. 261 The initial versions of G.709 referenced by [RFC4328] only provided a 262 single TS granularity, nominally 2.5Gbps. [G709-2012] added an 263 additional TS granularity, nominally 1.25Gbps. The number and type of 264 TSs provided by each of the currently identified OTUk is provided 265 below: 267 Tributary Slot Granularity 268 2.5Gbps 1.25Gbps Nominal Bit rate 269 OTU1 1 2 2.5Gbps 270 OTU2 4 8 10Gbps 271 OTU3 16 32 40Gbps 272 OTU4 -- 80 100Gbps 274 To maintain backwards compatibility while providing the ability to 275 interconnect nodes that support 1.25Gbps TS at one end of a link and 276 2.5Gbps TS at the other, [G709-2012] requires 'new' equipment fall 277 back to the use of a 2.5Gbps TS when connected to legacy equipment. 278 This information is carried in band by the payload type. 280 The actual bit rate of the TS in an OTUk depends on the value of k. 281 Thus the number of TSs occupied by an ODUj may vary depending on the 282 values of j and k. For example an ODU2e uses 9 TSs in an OTU3 but 283 only 8 in an OTU4. Examples of the number of TSs used for various 284 cases are provided below (Referring to Table 7-9 of [G709-2012]): 286 - ODU0 into ODU1, ODU2, ODU3 or ODU4 multiplexing with 1,25Gbps TS 287 granularity 288 o ODU0 occupies 1 of the 2, 8, 32 or 80 TSs for ODU1, ODU2, ODU3 289 or ODU4 291 - ODU1 into ODU2, ODU3 or ODU4 multiplexing with 1,25Gbps TS 292 granularity 293 o ODU1 occupies 2 of the 8, 32 or 80 TSs for ODU2, ODU3 or ODU4 295 - ODU1 into ODU2, ODU3 multiplexing with 2.5Gbps TS granularity 296 o ODU1 occupies 1 of the 4 or 16 TSs for ODU2 or ODU3 298 - ODU2 into ODU3 or ODU4 multiplexing with 1.25Gbps TS granularity 299 o ODU2 occupies 8 of the 32 or 80 TSs for ODU3 or ODU4 301 - ODU2 into ODU3 multiplexing with 2.5Gbps TS granularity 302 o ODU2 occupies 4 of the 16 TSs for ODU3 304 - ODU3 into ODU4 multiplexing with 1.25Gbps TS granularity 305 o ODU3 occupies 31 of the 80 TSs for ODU4 307 - ODUflex into ODU2, ODU3 or ODU4 multiplexing with 1.25Gbps TS 308 granularity 309 o ODUflex occupies n of the 8, 32 or 80 TSs for ODU2, ODU3 or 310 ODU4 (n <= Total TS number of ODUk) 312 - ODU2e into ODU3 or ODU4 multiplexing with 1.25Gbps TS granularity 313 o ODU2e occupies 9 of the 32 TSs for ODU3 or 8 of the 80 TSs for 314 ODU4 316 In general the mapping of an ODUj (including ODUflex) into a specific 317 OTUk TS is determined locally, and it can also be explicitly 318 controlled by a specific entity (e.g., head end, Network Management 319 System (NMS)) through Explicit Label Control [RFC3473]. 321 3.1.2.1. Structure of MSI information 323 When multiplexing an ODUj into a HO ODUk (k>j), G.709 specifies the 324 information that has to be transported in-band in order to allow for 325 correct demultiplexing. This information, known as MSI, is 326 transported in the OPUk overhead and is local to each link. In case 327 of bidirectional paths the association between TPN and TS must be the 328 same in both directions. 330 The MSI information is organized as a set of entries, with one entry 331 for each HO ODUj TS. The information carried by each entry is: 333 - Payload Type: the type of the transported payload. 335 - TPN: the port number of the ODUj transported by the HO ODUk. The 336 TPN is the same for all the TSs assigned to the transport of the 337 same ODUj instance. 339 For example, an ODU2 carried by a HO ODU3 is described by 4 entries 340 in the OPU3 overhead when the TS granularity is 2.5Gbps, and by 8 341 entries when the TS granularity is 1.25Gbps. 343 On each node and on every link, two MSI values have to be provisioned 344 (Referring to [G798-V4]): 346 - The Transmitted MSI (TxMSI) information inserted in OPU (e.g., 347 OPU3) overhead by the source of the HO ODUk trail. 349 - The expected MSI (ExMSI) information that is used to check the 350 accepted MSI (AcMSI) information. The AcMSI information is the MSI 351 valued received in-band, after a three-frame integration. 353 As described in [G798-V4], the sink of the HO ODU trail checks the 354 complete content of the AcMSI information against the ExMSI. If the 355 AcMSI is different from the ExMSI, then the traffic is dropped and a 356 payload mismatch alarm is generated. 358 Provisioning of TPN can be performed either by network management 359 system or control plane. In the last case, control plane is also 360 responsible for negotiating the provisioned values on a link by link 361 base. 363 4. Connection management in OTN 365 OTN-based connection management is concerned with controlling the 366 connectivity of ODU paths and OCh. This document focuses on the 367 connection management of ODU paths. The management of OCh paths is 368 described in [RFC6163]. 370 While [G872-2001] considered the ODU as a set of layers in the same 371 way as SDH has been modeled, recent ITU-T OTN architecture progress 372 [G872-2012] includes an agreement to model the ODU as a single layer 373 network with the bit rate as a parameter of links and connections. 374 This allows the links and nodes to be viewed in a single topology as 375 a common set of resources that are available to provide ODUj 376 connections independent of the value of j. Note that when the bit 377 rate of ODUj is less than the server bit rate, ODUj connections are 378 supported by HO ODU (which has a one-to-one relationship with the 379 OTU). 381 From an ITU-T perspective, the ODU connection topology is represented 382 by that of the OTU link layer, which has the same topology as that of 383 the OCh layer (independent of whether the OTU supports HO ODU, where 384 multiplexing is utilized, or LO ODU in the case of direct mapping). 385 Thus, the OTU and OCh layers should be visible in a single 386 topological representation of the network, and from a logical 387 perspective, the OTU and OCh may be considered as the same logical, 388 switchable entity. 390 Note that the OTU link layer topology may be provided via various 391 infrastructure alternatives, including point-to-point optical 392 connections, optical connections fully in the optical domain and 393 optical connections involving hybrid sub-lambda/lambda nodes 394 involving 3R, etc, see [RFC6163] for additional information. 396 4.1. Connection management of the ODU 398 LO ODUj can be either mapped into the OTUk signal (j = k), or 399 multiplexed with other LO ODUjs into an OTUk (j < k), and the OTUk is 400 mapped into an OCh. 402 From the perspective of control plane, there are two kinds of network 403 topology to be considered. 405 (1) ODU layer 407 In this case, the ODU links are presented between adjacent OTN nodes, 408 as illustrated in Figure 2. In this layer there are ODU links with a 409 variety of TSs available, and nodes that are Optical Digital Cross 410 Connects (ODXCs). Lo ODU connections can be setup based on the 411 network topology. 413 Link #5 +--+---+--+ Link #4 414 +--------------------------| |--------------------------+ 415 | | ODXC | | 416 | +---------+ | 417 | Node E | 418 | | 419 +-++---+--+ +--+---+--+ +--+---+--+ +--+---+-++ 420 | |Link #1 | |Link #2 | |Link #3 | | 421 | |--------| |--------| |--------| | 422 | ODXC | | ODXC | | ODXC | | ODXC | 423 +---------+ +---------+ +---------+ +---------+ 424 Node A Node B Node C Node D 426 Figure 2 - Example Topology for LO ODU connection management 428 If an ODUj connection is requested between Node C and Node E 429 routing/path computation must select a path that has the required 430 number of TS available and that offers the lowest cost. Signaling is 431 then invoked to set up the path and to provide the information (e.g., 432 selected TSs) required by each transit node to allow the 433 configuration of the ODUj to OTUk mapping (j = k) or multiplexing (j 434 < k), and demapping (j = k) or demultiplexing (j < k). 436 (2) ODU layer with OCh switching capability 438 In this case, the OTN nodes interconnect with wavelength switched 439 node (e.g., Reconfiguration Optical Add/Drop Multiplexer (ROADM), 440 Optical Cross-Connect (OXC)) that are capable of OCh switching, which 441 is illustrated in Figure 3 and Figure 4. There are ODU layer and OCh 442 layer, so it is simply a Multi-Layer Networks (MLN) (see [RFC6001]). 444 OCh connections may be created on demand, which is described in 445 section 5.1. 447 In this case, an operator may choose to allow the underlined OCh 448 layer to be visible to the ODU routing/path computation process in 449 which case the topology would be as shown in Figure 4. In Figure 3 450 below, instead, a cloud representing OCh capable switching nodes is 451 represented. In Figure 3, the operator choice is to hide the real OCh 452 layer network topology. 454 Node E 455 Link #5 +--------+ Link #4 456 +------------------------| |------------------------+ 457 | ------ | 458 | // \\ | 459 | || || | 460 | | OCh domain | | 461 +-+-----+ +------ || || ------+ +-----+-+ 462 | | | \\ // | | | 463 | |Link #1 | -------- |Link #3 | | 464 | +--------+ | | +--------+ + 465 | ODXC | | ODXC +--------+ ODXC | | ODXC | 466 +-------+ +---------+Link #2 +---------+ +-------+ 467 Node A Node B Node C Node D 469 Figure 3 - OCh Hidden Topology for LO ODU connection management 471 Link #5 +---------+ Link #4 472 +------------------------| |-----------------------+ 473 | +----| ODXC |----+ | 474 | +-++ +---------+ ++-+ | 475 | Node f | | Node E | | Node g | 476 | +-++ ++-+ | 477 | | +--+ | | 478 +-+-----+ +----+----+--| |--+-----+---+ +-----+-+ 479 | |Link #1 | | +--+ | |Link #3 | | 480 | +--------+ | Node h | +--------+ | 481 | ODXC | | ODXC +--------+ ODXC | | ODXC | 482 +-------+ +---------+ Link #2+---------+ +-------+ 483 Node A Node B Node C Node D 485 Figure 4 - OCh Visible Topology for LO ODUj connection management 487 In Figure 4, the cloud of previous figure is substitute by the real 488 topology. The nodes f, g, h are nodes with OCh switching capability. 490 In the examples (i.e., Figure 3 and Figure 4), we have considered the 491 case in which LO ODUj connections are supported by OCh connection, 492 and the case in which the supporting underlying connection can be 493 also made by a combination of HO ODU/OCh connections. 495 In this case, the ODU routing/path selection process will request an 496 HO ODU/OCh connection between node C and node E from the OCh domain. 497 The connection will appear at ODU level as a Forwarding Adjacency, 498 which will be used to create the ODU connection. 500 5. GMPLS/PCE Implications 502 The purpose of this section is to provide a set of requirements to be 503 evaluated for extensions of the current GMPLS protocol suite and the 504 PCE applications and protocols to encompass OTN enhancements and 505 connection management. 507 5.1. Implications for Label Switch Path (LSP) Hierarchy 509 The path computation for ODU connection request is based on the 510 topology of ODU layer. 512 The OTN path computation can be divided into two layers. One layer is 513 OCh/OTUk, the other is ODUj. [RFC4206] and [RFC6107] define the 514 mechanisms to accomplish creating the hierarchy of LSPs. The LSP 515 management of multiple layers in OTN can follow the procedures 516 defined in [RFC4206], [RFC6001] and [RFC6107], etc. 518 As discussed in section 4, the route path computation for OCh is in 519 the scope of Wavelength Switched Optical Network (WSON) [RFC6163]. 520 Therefore, this document only considers ODU layer for ODU connection 521 request. 523 LSP hierarchy can also be applied within the ODU layers. One of the 524 typical scenarios for ODU layer hierarchy is to maintain 525 compatibility with introducing new [G709-2012] services (e.g., ODU0, 526 ODUflex) into a legacy network configuration (i.e., the legacy OTN 527 referenced by [RFC4328]). In this scenario, it may be needed to 528 consider introducing hierarchical multiplexing capability in specific 529 network transition scenarios. One method for enabling multiplexing 530 hierarchy is by introducing dedicated boards in a few specific places 531 in the network and tunneling these new services through the legacy 532 containers (ODU1, ODU2, ODU3), thus postponing the need to upgrade 533 every network element to [G709-2012] capabilities. 535 In such case, one ODUj connection can be nested into another ODUk 536 (j +----------+ 873 | TS1==|===========\--------+--TS1 | 874 | TS2==|=========\--\-------+--TS2 | 875 | TS3==|=======\--\--\------+--TS3 | 876 | TS4==|=====\--\--\--\-----+--TS4 | 877 | | \ \ \ \----+--TS5 | 878 | | \ \ \------+--TS6 | 879 | | \ \--------+--TS7 | 880 | | \----------+--TS8 | 881 +----------+ <------------ +----------+ 882 node A Resv node B 884 Figure 5 - Interworking between 1.25Gbps TS and 2.5Gbps TS 886 Take Figure 5 as an example. Assume that there is an ODU2 link 887 between node A and B, where node A only supports the 2.5Gbps TS while 888 node B supports the 1.25Gbps TS. In this case, the TS#i and TS#i+4 889 (where i<=4) of node B are combined together. When creating an ODU1 890 service in this ODU2 link, node B reserves the TS#i and TS#i+4 with 891 the granularity of 1.25Gbps. But in the label sent from B to A, it is 892 indicated that the TS#i with the granularity of 2.5Gbps is reserved. 894 In the opposite direction, when receiving a label from node A 895 indicating that the TS#i with the granularity of 2.5Gbps is reserved, 896 node B will reserved the TS#i and TS#i+4 with the granularity of 897 1.25Gbps in its data plane. 899 7. Security Considerations 901 The use of control plane protocols for signaling, routing and path 902 computation opens an OTN to security threats through attacks on those 903 protocols. Although, this is not greater than the risks presented by 904 the existing OTN control plane as defined by [RFC4203] and [RFC4328]. 905 Meanwhile, the Data Communication Network (DCN) for OTN GMPLS control 906 plane protocols is likely to be in the in-fiber overhead, which 907 together with access lists at the network edges, provides a 908 significant security feature. For further details of the specific 909 security measures refer to the documents that define the protocols 910 ([RFC3473], [RFC4203], [RFC5307], [RFC4204] and [RFC5440]). [RFC5920] 911 provides an overview of security vulnerabilities and protection 912 mechanisms for the GMPLS control plane. 914 8. IANA Considerations 916 This document makes not requests for IANA action. 918 9. Acknowledgments 920 We would like to thank Maarten Vissers and Lou Berger for their 921 review and useful comments. 923 10. References 925 10.1. Normative References 927 [RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V. 928 and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP 929 Tunnels", RFC 3209, December 2001. 931 [RFC3471] Berger, L., Editor, "Generalized Multi-Protocol Label 932 Switching (GMPLS) Signaling Functional Description", RFC 933 3471, January 2003. 935 [RFC3473] L. Berger, Ed., "Generalized Multi-Protocol Label 936 Switching (GMPLS) Signaling Resource ReserVation 937 Protocol-Traffic Engineering (RSVP-TE) Extensions", RFC 938 3473, January 2003. 940 [RFC4201] K. Kompella, Y. Rekhter, Ed., "Link Bundling in MPLS 941 Traffic Engineering (TE)", RFC 4201, October 2005. 943 [RFC4202] K. Kompella, Y. Rekhter, Ed., "Routing Extensions in 944 Support of Generalized Multi-Protocol Label Switching 945 (GMPLS)", RFC 4202, October 2005. 947 [RFC4203] K. Kompella, Y. Rekhter, Ed., "OSPF Extensions in Support 948 of Generalized Multi-Protocol Label Switching (GMPLS)", 949 RFC 4203, October 2005. 951 [RFC4204] Lang, J., Ed., "Link Management Protocol (LMP)", RFC 952 4204, October 2005. 954 [RFC4206] K. Kompella, Y. Rekhter, Ed., "Label Switched Paths (LSP) 955 Hierarchy with Generalized Multi-Protocol Label Switching 956 (GMPLS) Traffic Engineering (TE)", RFC 4206, October 957 2005. 959 [RFC4328] D. Papadimitriou, Ed. "Generalized Multi-Protocol 960 LabelSwitching (GMPLS) Signaling Extensions for G.709 961 Optical Transport Networks Control", RFC 4328, Jan 2006. 963 [RFC5307] K. Kompella, Y. Rekhter, Ed., "IS-IS Extensions in 964 Support of Generalized Multi-Protocol Label Switching 965 (GMPLS)", RFC 5307, October 2008. 967 [RFC5440] JP. Vasseur, JL. Le Roux, Ed.," Path Computation Element 968 (PCE) Communication Protocol (PCEP)", RFC 5440, March 969 2009. 971 [RFC6001] Dimitri Papadimitriou et al, "Generalized Multi-Protocol 972 Label Switching (GMPLS) Protocol Extensions for Multi- 973 Layer and Multi-Region Networks (MLN/MRN)", RFC6001, 974 February 21, 2010. 976 [RFC6107] K. Shiomoto, A. Farrel, "Procedures for Dynamically 977 Signaled Hierarchical Label Switched Paths", RFC6107, 978 February 2011. 980 [RFC6344] G. Bernstein et al, "Operating Virtual Concatenation 981 (VCAT) and the Link Capacity Adjustment Scheme (LCAS) 982 with Generalized Multi-Protocol Label Switching (GMPLS)", 983 RFC6344, August, 2011. 985 [G709-2012] ITU-T, "Interface for the Optical Transport Network 986 (OTN)", G.709/Y.1331 Recommendation, February 2012. 988 10.2. Informative References 990 [G798-V4] ITU-T, "Characteristics of optical transport network 991 hierarchy equipment functional blocks", G.798 992 Recommendation, October 2010. 994 [G7042] ITU-T, "Link capacity adjustment scheme (LCAS) for 995 virtual concatenated signals", G.7042/Y.1305, March 2006. 997 [G872-2001] ITU-T, "Architecture of optical transport networks", 998 G.872 Recommendation, November 2001. 1000 [G872-2012] ITU-T, "Architecture of optical transport networks", 1001 G.872 Recommendation, October 2012. 1003 [G7044] ITU-T, "Hitless adjustment of ODUflex", G.7044/Y.1347, 1004 October 2011. 1006 [G7041] ITU-T, "Generic framing procedure", G.7041/Y.1303, April 1007 2011. 1009 [RFC3945] Mannie, E., "Generalized Multi-Protocol Label Switching 1010 (GMPLS) Architecture", RFC 3945, October 2004. 1012 [RFC4655] Farrel, A., Vasseur, J., and J. Ash, "A Path 1013 Computation Element (PCE)-Based Architecture", 1014 RFC 4655, August 2006. 1016 [RFC6163] Y. Lee, G. Bernstein, W. Imajuku, "Framework for GMPLS 1017 and PCE Control of Wavelength Switched Optical Networks 1018 (WSON)", RFC6163, April 2011. 1020 [PCE-APS] Tomohiro Otani, Kenichi Ogaki, Diego Caviglia, and Fatai 1021 Zhang, "Requirements for GMPLS applications of PCE", 1022 draft-ietf-pce-gmpls-aps-req, Work in Progress. 1024 [RFC5920] Fang, L., Ed., "Security Framework for MPLS and GMPLS 1025 Networks", RFC5920, July 2010. 1027 [TDM-OAM] A. Kern, A. Takacs, "GMPLS RSVP-TE Extensions for 1028 SONET/SDH and OTN OAM Configuration", draft-ietf-ccamp- 1029 rsvp-te-sdh-otn-oam-ext, Work in Progress. 1031 11. Authors' Addresses 1033 Fatai Zhang (editor) 1034 Huawei Technologies 1035 F3-5-B R&D Center, Huawei Base 1036 Bantian, Longgang District 1037 Shenzhen 518129 P.R.China 1039 Phone: +86-755-28972912 1040 Email: zhangfatai@huawei.com 1042 Dan Li 1043 Huawei Technologies Co., Ltd. 1044 F3-5-B R&D Center, Huawei Base 1045 Bantian, Longgang District 1046 Shenzhen 518129 P.R.China 1048 Phone: +86-755-28973237 1049 Email: huawei.danli@huawei.com 1051 Han Li 1052 China Mobile Communications Corporation 1053 53 A Xibianmennei Ave. Xuanwu District 1054 Beijing 100053 P.R. China 1056 Phone: +86-10-66006688 1057 Email: lihan@chinamobile.com 1059 Sergio Belotti 1060 Alcatel-Lucent 1061 Optics CTO 1062 Via Trento 30 20059 Vimercate (Milano) Italy 1063 +39 039 6863033 1065 Email: sergio.belotti@alcatel-lucent.it 1067 Daniele Ceccarelli 1068 Ericsson 1069 Via A. Negrone 1/A 1070 Genova - Sestri Ponente 1071 Italy 1072 Email: daniele.ceccarelli@ericsson.com 1074 12. Contributors 1076 Jianrui Han 1077 Huawei Technologies Co., Ltd. 1078 F3-5-B R&D Center, Huawei Base 1079 Bantian, Longgang District 1080 Shenzhen 518129 P.R.China 1082 Phone: +86-755-28972913 1083 Email: hanjianrui@huawei.com 1085 Malcolm Betts 1086 Huawei Technologies Co., Ltd. 1088 Email: malcolm.betts@huawei.com 1089 Pietro Grandi 1090 Alcatel-Lucent 1091 Optics CTO 1092 Via Trento 30 20059 Vimercate (Milano) Italy 1093 +39 039 6864930 1095 Email: pietro_vittorio.grandi@alcatel-lucent.it 1097 Eve Varma 1098 Alcatel-Lucent 1099 1A-261, 600-700 Mountain Av 1100 PO Box 636 1101 Murray Hill, NJ 07974-0636 1102 USA 1103 Email: eve.varma@alcatel-lucent.com 1105 Intellectual Property 1107 The IETF Trust takes no position regarding the validity or scope of 1108 any Intellectual Property Rights or other rights that might be 1109 claimed to pertain to the implementation or use of the technology 1110 described in any IETF Document or the extent to which any license 1111 under such rights might or might not be available; nor does it 1112 represent that it has made any independent effort to identify any 1113 such rights. 1115 Copies of Intellectual Property disclosures made to the IETF 1116 Secretariat and any assurances of licenses to be made available, or 1117 the result of an attempt made to obtain a general license or 1118 permission for the use of such proprietary rights by implementers or 1119 users of this specification can be obtained from the IETF on-line IPR 1120 repository at http://www.ietf.org/ipr 1122 The IETF invites any interested party to bring to its attention any 1123 copyrights, patents or patent applications, or other proprietary 1124 rights that may cover technology that may be required to implement 1125 any standard or specification contained in an IETF Document. 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