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Ali 11 Cisco 12 October 30, 2017 14 GMPLS Routing and Signaling Framework for B100G 15 draft-merge-ccamp-100g-signalling-00 17 Abstract 19 This document provides extensions to GMPLS signalling to control the 20 B100G OTUCn/ODUCn Network, as a result of the introduction of new 21 beyond 100G OTUCn/ODUCn signals and features in ITU-T Recommendation 22 [ITU-T_G709_2016]. 24 Status of This Memo 26 This Internet-Draft is submitted in full conformance with the 27 provisions of BCP 78 and BCP 79. 29 Internet-Drafts are working documents of the Internet Engineering 30 Task Force (IETF). Note that other groups may also distribute 31 working documents as Internet-Drafts. The list of current Internet- 32 Drafts is at https://datatracker.ietf.org/drafts/current/. 34 Internet-Drafts are draft documents valid for a maximum of six months 35 and may be updated, replaced, or obsoleted by other documents at any 36 time. It is inappropriate to use Internet-Drafts as reference 37 material or to cite them other than as "work in progress." 39 This Internet-Draft will expire on May 3, 2018. 41 Copyright Notice 43 Copyright (c) 2017 IETF Trust and the persons identified as the 44 document authors. All rights reserved. 46 This document is subject to BCP 78 and the IETF Trust's Legal 47 Provisions Relating to IETF Documents 48 (https://trustee.ietf.org/license-info) in effect on the date of 49 publication of this document. Please review these documents 50 carefully, as they describe your rights and restrictions with respect 51 to this document. Code Components extracted from this document must 52 include Simplified BSD License text as described in Section 4.e of 53 the Trust Legal Provisions and are provided without warranty as 54 described in the Simplified BSD License. 56 Table of Contents 58 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 59 2. Requirements Language . . . . . . . . . . . . . . . . . . . . 3 60 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 61 4. Overview of the GMPLS Extensions for Support of OTUCn/ODUCn . 3 62 5. Generalized Label Request . . . . . . . . . . . . . . . . . . 4 63 5.1. LSP Encoding Type . . . . . . . . . . . . . . . . . . . . 5 64 5.2. Generalized-PID . . . . . . . . . . . . . . . . . . . . . 5 65 5.3. Traffic Parameters for OTUCn/ODUCn in G.709 . . . . . . . 6 66 5.4. Unavailable slots collection TLV . . . . . . . . . . . . 7 67 6. Generalized Label . . . . . . . . . . . . . . . . . . . . . . 7 68 6.1. Label Format . . . . . . . . . . . . . . . . . . . . . . 7 69 6.2. Procedures . . . . . . . . . . . . . . . . . . . . . . . 8 70 7. Security Considerations . . . . . . . . . . . . . . . . . . . 10 71 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 72 9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 10 73 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 10 74 10.1. Normative References . . . . . . . . . . . . . . . . . . 10 75 10.2. Informative References . . . . . . . . . . . . . . . . . 11 76 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11 78 1. Introduction 80 The 2016 version of [ITU-T_G709_2016] introduces support for higher 81 rate OTU and ODU signals, termed OTUCn and ODUCn (which have a 82 nominal rate of 100n Gbps). The newly introduced OTUCn and ODUCn 83 represent a powerful extension to the OTN capabilities, and one which 84 naturally scales to transport any newer clients with bit rates in 85 excess of 100G, as they are introduced. 87 B100G framework document [I-D.merge-ccamp-otn-b100g-fwk] provides an 88 overview of the changes and identify the protocol extensions that 89 would be required to support GMPLS control of OTUCn/ODUCn as 90 specified in [ITU-T_G709_2016]. Based on the framework, this 91 document provide Resource Reservation Protocol - Traffic Engineering 92 (RSVP-TE) extensions to support control of OTUCn/ODUCn. 94 Note: according to the description in 95 [I-D.merge-ccamp-otn-b100g-fwk], the setup of ODUk over ODUCn can 96 reuse the extensions defined in [RFC7139]. 98 2. Requirements Language 100 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 101 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 102 document are to be interpreted as described in RFC 2119 [RFC2119]. 104 3. Terminology 106 a. OPUCn: Optical Payload Unit -Cn. 108 b. ODUCn: Optical Data Unit - Cn. 110 c. OTUCn: Fully standardized Optical Transport Unit - Cn. 112 d. OTUCn-M: This signal is an extension of the OTUCn signal 113 introduced above. This signal contains the same amount of 114 overhead as the OTUCn signal, but contains a reduced amount of 115 payload area. Specifically the payload area consists of M 5G 116 tributary slots (where M is strictly less than 20*n). 118 4. Overview of the GMPLS Extensions for Support of OTUCn/ODUCn 120 As the new OTUCn/ODUCn signal and features are introduced in 121 [ITU-T_G709_2016], corresponding new Signal Types are defined below 122 as required: 124 completely standardized Optical Transport Unit-Cn (OTUCn) 126 Optical Transport Unit-Cn with n OxUC overhead instances and M 5G 127 tributary slots (OTUCn-M) 129 Optical Data Unit-Cn (ODUCn) 131 A new tributary slot granularity (i.e., 5Gbps) is defined in 132 [ITU-T_G709_2016]. This granularity is specially used to support 133 OPUCn/ODUCn/OTUCn in B100G OTN networks. Tributary slot is defined 134 with a bandwidth of approximately 5 Gbit/s; an OPUCn/ODUCn/OTUCn 135 contains 20n tributary slots, numbered 1.1 to n.20. Legacy OTN 136 interfaces will continue to use 2.5Gbps/1.25Gbps tributary slot 137 granularity. 139 The OTUCn/ODUCn/OPUCn consists of n OTUC/ODUC/OPUC. Each of them 140 contains 20 tributary slots (TS) and these tributary slots are 141 interleaved within the payload area. Each OTUCn/ODUCn/OPUCn includes 142 a part of the OH area and a part of the payload area. An ODUCn 143 carries n instances of the ODUC overhead, OPUC overhead and OPUC 144 payload. An OTUCn carries n instances of the OTUC overhead, ODUC 145 overhead and ODUC payload. ODUk frame are mapped into the OPUCn 146 tributary slots. The main difference between OTUCn/ODUCn/OPUCn 147 signal and legacy ODUk signal defined in [ITU-T_G709_2012] is how to 148 transfer these signals. As described in 149 [I-D.merge-ccamp-otn-b100g-fwk], an OTUCn can be transported over a 150 bunch of interfaces, with each OTUC instances maybe distributed over 151 different interfaces. These interfaces are bonded together as a 152 single group. The ODUCn / OTUCn connection does not exist at the 153 time the network is deployed. Signalling is neede to finish the 154 setup of ODUCn / OTUCn connection. 156 The implementation of the OTUCn/ODUCn Signal which has been briefly 157 described in [I-D.merge-ccamp-otn-b100g-fwk], which may be achieved 158 through the bonding of FlexO interfaces referred to as PHYs. Higher 159 rate OTUCn is split into n instances of OTUC at the FlexO source 160 nodes. One or more OTUC instances are associated with one FlexO 161 interface. Several end-to-end FlexO connections (PHYs) are bonded 162 together as one FlexO group to carry the OTUCn. The Ethernet PHYs 163 are used as the server layer of the OTUCn signal. The OTU layer 164 views FlexO (even if there are some digital sub-layers involved in 165 the adaptation) and other OTUCn transport mechanisms as "lower 166 layers", and are therefore considered out-of-scope. GMPLS extensions 167 in this draft only consider the use of signalling to set up ODUCn/ 168 OTUCn connection. 170 The OTUCn-M signal is derived from the OTUCn signal by retaining all 171 the n instances of overhead (one per OTUC slice) and crunching the 172 OPUC tributary slots marked as "unavailable". Signalling should be 173 able to set up OTUCn-M connection by discarding the unavailable slots 174 at the source node and restoring the unavailable slots at the sink 175 node. 177 Virtual Concatenation (VCAT) of Optical channel Payload Unit-k (OPUk) 178 and ODUCn is not supported by [ITU-T_G709_2016] any more.New traffic 179 parameters for ODUCn/OTUCn are redefined in this draft to reflect the 180 changes. 182 5. Generalized Label Request 184 As defined in [RFC3471], the Generalized Label Request includes a 185 common part (i.e., used for any switching technology) and a 186 technology dependent part (i.e., the traffic parameters). Both of 187 these two parts are extended in [RFC4328] and [RFC7139] to 188 accommodate GMPLS Signalling to the G.709 transport plane technology 189 as a result of the introduction of new signal and features. 191 In this document, the LSP Encoding Type in the common part and the 192 traffic parameter in the technology dependent part are extended/ 193 refined to accommodate the G.709 Recommendation [ITU-T_G709_2016]. 195 5.1. LSP Encoding Type 197 In [ITU-T_G709_2016], the ODUCn is used as a high-order signal only. 198 Only lower-rate (i.e. low-order) ODUs can be multiplexed onto an 199 ODUCn signal; In other words, non-OTN client signals can not be 200 directly mapped to an ODUCn signal.It must first be mapped on the 201 ODUk signal and then traversed through the ODUCn network. 203 Additionally, [RFC4328] introduces two new code-points for the LSP 204 encoding type, one of them is G.709 ODUk digital path. This encoding 205 type can not be used to describe ODUCn , as ODUCn is not switchable 206 and it can only perform digital section layer role. This is 207 different from ODUk.Based on these analysis, a new code-points for 208 the LSP Encoding Type is defined in Figure 1. When signalling is 209 used to set up ODUCn/OTUCn LSP, this encoding type can be used to 210 represent the nature of the LSP. 212 ================================================= 214 Value Type 215 ----- ---- 216 XX G.709 ODUCn (Digital section) 218 ================================================= 220 Figure 1: ODUCn Encoding Type 222 5.2. Generalized-PID 224 This document follows the these extensions defined in [RFC4328] and 225 [RFC7139]. New G-PID values are described as follows according to 226 update defined in Table 15-8 of [ITU-T_G709_2016]. One thing should 227 be noted is the new G-PIDs introduced in this section are just used 228 to update [RFC4328] and [RFC7139], as ODUCn can only be used to carry 229 ODUk or ODUflex signals, non-OTN client signals must first be mapped 230 onto ODUk or ODUflex, then over ODUCn. 232 ================================================= 234 Value G-PID Type 235 ----- ---------- 236 TBA New type added to indicate the transportation of "G.709 ODUk" digital Paths over "ODUCn" via 5 Gbps TS granularity. 237 TBA New Type field added to indicate the transportation of FC-3200 over ODUflex. 238 TBA New Type field added to indicate the transportation of FlexE client signal over ODUflex. 239 TBA New Type field added to indicate the transportation of FlexE aware signal over ODUflex. 241 ================================================= 243 Figure 2: G-PID 245 The full list of payload types defined in [ITU-T_G709_2016] and their 246 mapping to existing and new G-PID types are as follows: 248 [Editor Note: to be added later.] 250 5.3. Traffic Parameters for OTUCn/ODUCn in G.709 252 Section 3.2 of [RFC4328] is the first place to define the traffic 253 parameters of OTN, and [RFC7139] extends the format by adding the 254 Bit_Rate field and deleting the NMC (Number of Multiplexed 255 Components).ODUCn specific technology traffic parameters are needed 256 when requesting the OTUCn/ODUCn LSP. 258 This document refine the Traffic Parameter format defined in section 259 5 of [RFC7139] to carry ODUCn specific parameters. Based on the 260 description in [ITU-T_G709_2016], this document removes the NVC 261 (Number of Virtual Components), as ODUCn is not able to support 262 virtual concatenation and multiplication.This Traffic Parameters for 263 the ODUCn/OTUCn are carried in the SENDER_TSPEC object in the Path 264 message and the FLOWSPEC object in the Resv message. New C-Type for 265 SENDER_TSPEC and FLOWSPEC are defined in this document. 267 SENDER_TSPEC object for ODUCn/OTUCn: Class = 12, C-Type = TBD 269 FLOWSPEC object for ODUCn/OTUCn: Class = 9, C-Type = TBD 270 0 1 2 3 271 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 272 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 273 | Signal Type | n | Multiplier (MT) | 274 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 275 | Bit_Rate | 276 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 278 Figure 3: Traffic Parameters 280 Signal Type: three new signal types (i.e., OTUCn, OTUCn-M, ODUCn) are 281 defined in this document. 283 n (8 bits): "n" is an positive integer and contained in "OTUCn/OTUCn- 284 M/ODUCn", and it can used to represent the bandwidth resource being 285 requested. Also "n" is equal to the number of the OTUC/ODUC/OPUC 286 instances. 288 MT (Multiplexer): defined in section 3.2.4 of [RFC4328]. 290 Bit_Rate: defined in section 5 of [RFC7139]. In this draft, this 291 filed is extended to indicate the nominal bit rate of ODUCn expressed 292 in bytes per second, encoded as a 32-bit IEEE single-precision 293 floating-point number (referring to [RFC4506] and [IEEE]). 295 5.4. Unavailable slots collection TLV 297 When signalling is used to set up OTUCn-M LSP, a new LSP_ATTRIBUTE 298 TLV may be needed to negotiate the number and position of the 299 unavailable slots at two ends of each ODUC link in the LSP to be set 300 up, so the destination node can compute a proper label. This value 301 part of this TLV has the same format as the GMPLS label for setting 302 up ODUCn LSP. 304 6. Generalized Label 306 The generalized label defined in this section can be used to indicate 307 how the OTUCn/OTUCn-M/ODUCn LSP is created, how each ODUC/OTUC 308 instances are bonded together, which can be treated as a link for the 309 client ODUk signal. 311 6.1. Label Format 313 Following is the GENERALIZED_LABEL object format for OTUCn/OTUCn-M/ 314 ODUCn.The label contains one or more OTUC/ODUC instances which are 315 bonded together as a single ODUCn/OTUCn signal. ODUCn LSP can be 316 used as a link for client ODUk signal.The label is mainly used to 317 indicate how to distribute ODUC instances over different interfaces 318 and these ODUC instances are bonded together as one group. 320 0 1 2 3 321 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 322 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 323 | Instance ID | BitMap Length | NUS | Reserved | 324 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 325 | Slots BitMap | 326 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 327 | | 328 ~ slots assignment information ~ 329 | | 330 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 331 | Instance ID | BitMap Length | NUS | Reserved | 332 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 333 | Slots BitMap | 334 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 336 Figure 4: Label 338 Instance ID: the indication of the ODUC. 340 BitMap Length: indicate the length of the slots BitMap. 342 Slot BitMap: when the label is used to set up OTUCn-M path, this 343 field is used to represent the position of unavailable slots. When 344 the label is used to set up OTUCn/ODUCn path, the bitmap field can be 345 set to 0, as there is no indication for allocating slots. When the 346 label is used to set up ODUk path, this field is used to represent 347 the ODUCn slots resource allocated for ODUk signal. 349 NUS (Number of Unavailable Slots): indicate the number of unavailable 350 slots. 352 This GENERALIZED_LABEL object contains several label blocks, with 353 each block correspond to one OTUC/ODUC instance. 355 6.2. Procedures 357 This section does not change the procedure of RSVP-TE protocol 358 described in section 6.2 of [RFC7139], like birdirectional LSP, 359 LABEL_SET object. 361 When the source node receives the command from EMS or trigger from 362 upper layer, and then decide to set up an ODUCn LSP.The path 363 computation module is first used to compute an available path for 364 ODUCn LSP, after the computation, how many and which ODUC instances 365 would be involved can be known, then the Path message containing a 366 traffic parameters in the SENDER_TSPEC object for ODUCn LSP is 367 created according to the computation result.Unavailable slots 368 collection TLV must be carried to collect the number and position of 369 the unavailable slots if there exist OTUC instances with unavailable 370 slots between the ODUCn source and sink terminating nodes. 372 Before the sending of the ODUCn path message, an OTUCn LSP or OTUCn-M 373 LSP needs to be set up first to carry the ODUCn signal.The 374 information of OTUC instances involved would be notified to OTUCn 375 path setup module by ODUCn path setup module. An OTUCn or OTUCn-M 376 path message with traffic parameters and is created at the source 377 OTUCn or OTUCn-M terminating node and sent to the sink OTUCn or 378 OTUCn-M terminating node.Unavailable slots collection TLV may not be 379 neede, as even there are unavailable slots on this OTUCn link, they 380 can be configured by manual or dynamic negotiation. Upon receiving 381 the Path message, OTUCn or OTUCn-M sink terminating node then replies 382 with a resv message towards the source terminating node and finish 383 the bonding of n OTUC instances. The bitMap Length field of label 384 would be set to 0. 386 The ODUCn Path message is then sent to the next hop which is actually 387 the OTUCn or OTUCn-M sink terminating node. As one ODUCn LSP may be 388 carried over several different OTUCn LSPs or OTUCn-M LSPs, this hop 389 maybe an intermediate ODUCn hop or sink terminating node. If it is 390 an ODUCn sink terminating node, Resv message is then created and sent 391 to the source, finish the bonding of n ODUC instances. If it is an 392 intemediate hop, then the above procedure would be repeat until the 393 ODUCn sink terminating node. 395 The IF_ID RSVP_HOP object must be used in Resv message, and it 396 contains several TLVs with each of them has an one-to-one 397 relationship to the instance in the label.In another word, which 398 component interface is used to carry a specific OTUC/ODUC instance 399 needs to be explicitly specified. 401 In the case of setup of OTUCn, which means there does not exist any 402 unavailable slot between ODUCn source and sink terminating node, bit 403 Map information is not required and MUST NOT be included, so the 404 Length field MUST be set to 0 as well. The NUS field should be set 405 to 0. 407 In the case of setup of OTUCn-M, the NUS field is set to indicate the 408 number of unavailable in this connection, and the postions of these 409 slots are indicated by the Bit map field. Unavailable slots can not 410 be assigned to client signal and this information should be aware of 411 by ODUCn layer. 413 ERO can be used to indicate the nodes and Ports which would be passed 414 through in the Path message after path computation in according to 415 the resource information at each nodes and ports. 417 7. Security Considerations 419 8. IANA Considerations 421 9. Contributors 423 Iftekhar Hussain, Infinera Corp, IHussain@infinera.com 425 Zheyu Fan, Huawei, fanzheyu2@huawei.com 427 Yunbin Xu, CAICT, xuyunbin@ritt.cn 429 Sergio Belotti, NOKIA, Sergio Belotti@nokia.com 431 10. References 433 10.1. Normative References 435 [ITU-T_G709.1] 436 ITU-T, "ITU-T G.709.1: Flexible OTN short-reach interface; 437 2016", , 2016. 439 [ITU-T_G709_2012] 440 ITU-T, "ITU-T G.709: Optical Transport Network Interfaces; 441 02/2012", http://www.itu.int/rec/T-REC- 442 G..709-201202-S/en, February 2012. 444 [ITU-T_G709_2016] 445 ITU-T, "ITU-T G.709: Optical Transport Network Interfaces; 446 07/2016", http://www.itu.int/rec/T-REC- 447 G..709-201606-P/en, July 2016. 449 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 450 Requirement Levels", BCP 14, RFC 2119, 451 DOI 10.17487/RFC2119, March 1997, 452 . 454 [RFC3471] Berger, L., Ed., "Generalized Multi-Protocol Label 455 Switching (GMPLS) Signaling Functional Description", 456 RFC 3471, DOI 10.17487/RFC3471, January 2003, 457 . 459 [RFC4328] Papadimitriou, D., Ed., "Generalized Multi-Protocol Label 460 Switching (GMPLS) Signaling Extensions for G.709 Optical 461 Transport Networks Control", RFC 4328, 462 DOI 10.17487/RFC4328, January 2006, 463 . 465 [RFC4506] Eisler, M., Ed., "XDR: External Data Representation 466 Standard", STD 67, RFC 4506, DOI 10.17487/RFC4506, May 467 2006, . 469 [RFC7139] Zhang, F., Ed., Zhang, G., Belotti, S., Ceccarelli, D., 470 and K. Pithewan, "GMPLS Signaling Extensions for Control 471 of Evolving G.709 Optical Transport Networks", RFC 7139, 472 DOI 10.17487/RFC7139, March 2014, 473 . 475 10.2. Informative References 477 [I-D.merge-ccamp-otn-b100g-fwk] 478 Wang, Q., Valiveti, R., zhenghaomian@huawei.com, z., 479 Helvoort, H., and S. Belotti, "GMPLS Routing and Signaling 480 Framework for B100G", draft-merge-ccamp-otn-b100g-fwk-01 481 (work in progress), July 2017. 483 Authors' Addresses 485 Qilei Wang 486 ZTE 487 Nanjing 488 CN 490 Email: wang.qilei@zte.com.cn 492 Haomian Zheng 493 Huawei 494 CN 496 Email: zhenghaomian@huawei.com 498 Radha Valiveti 499 Infinera Corp 500 Sunnyvale 501 USA 503 Email: rvaliveti@infinera.com 504 Huub van Helvoort 505 Hai Gaoming B.V 507 Email: huubatwork@gmail.com 509 Zafar Ali 510 Cisco 512 Email: zali@cisco.com