idnits 2.17.1 draft-wangl-ccamp-ospf-ext-constraint-flexi-grid-02.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- No issues found here. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document date (July 16, 2012) is 4301 days in the past. 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Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Unused Reference: 'I-D.hussain-ccamp-super-channel-label' is defined on line 901, but no explicit reference was found in the text == Unused Reference: 'I-D.zhang-ccamp-flexible-grid-requirements' is defined on line 925, but no explicit reference was found in the text == Unused Reference: 'I-D.zhang-ccamp-flexible-grid-rsvp-te-ext' is defined on line 930, but no explicit reference was found in the text == Unused Reference: 'I-D.zhangj-ccamp-flexi-grid-ospf-te-ext' is defined on line 935, but no explicit reference was found in the text -- Possible downref: Non-RFC (?) normative reference: ref. 'G.694.1v2' -- Possible downref: Non-RFC (?) normative reference: ref. 'ITU-T WD12R2' ** Downref: Normative reference to an Informational RFC: RFC 6163 -- No information found for draft-li-ccamp-flexible-grid-label - is the name correct? -- No information found for draft-zhangj-ccamp-flexi-grid-ospf-te-ext - is the name correct? Summary: 1 error (**), 0 flaws (~~), 5 warnings (==), 6 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group L. Wang 3 Internet-Draft Y. Li 4 Intended status: Standards Track ZTE 5 Expires: January 17, 2013 GY. Zhang 6 China Academy of Telecom 7 Research, MIIT 8 July 16, 2012 10 OSPF Extensions for Routing Constraint Encoding in Flexible-Grid 11 Networks 12 draft-wangl-ccamp-ospf-ext-constraint-flexi-grid-02 14 Abstract 16 In Flexible-Grid networks, network elements and links may impose 17 additional routing constraints, which cannot be ignored in Routing 18 and Spectrum Assignment (RSA) process. This document describes the 19 requirements of such constraints, and then provides efficient 20 encodings to specify how the information is carried. 22 Status of this Memo 24 This Internet-Draft is submitted in full conformance with the 25 provisions of BCP 78 and BCP 79. 27 Internet-Drafts are working documents of the Internet Engineering 28 Task Force (IETF). Note that other groups may also distribute 29 working documents as Internet-Drafts. The list of current Internet- 30 Drafts is at http://datatracker.ietf.org/drafts/current/. 32 Internet-Drafts are draft documents valid for a maximum of six months 33 and may be updated, replaced, or obsoleted by other documents at any 34 time. It is inappropriate to use Internet-Drafts as reference 35 material or to cite them other than as "work in progress." 37 This Internet-Draft will expire on January 17, 2013. 39 Copyright Notice 41 Copyright (c) 2012 IETF Trust and the persons identified as the 42 document authors. All rights reserved. 44 This document is subject to BCP 78 and the IETF Trust's Legal 45 Provisions Relating to IETF Documents 46 (http://trustee.ietf.org/license-info) in effect on the date of 47 publication of this document. Please review these documents 48 carefully, as they describe your rights and restrictions with respect 49 to this document. Code Components extracted from this document must 50 include Simplified BSD License text as described in Section 4.e of 51 the Trust Legal Provisions and are provided without warranty as 52 described in the Simplified BSD License. 54 Table of Contents 56 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 57 2. Conventions Used in This Document . . . . . . . . . . . . . . 3 58 3. Terminologies . . . . . . . . . . . . . . . . . . . . . . . . 3 59 4. Requirements of Routing Constraint for RSA in 60 Flexible-Grid Networks . . . . . . . . . . . . . . . . . . . . 4 61 4.1. Label set . . . . . . . . . . . . . . . . . . . . . . . . 8 62 4.2. Flexible-Grid Ability Constraint . . . . . . . . . . . . . 8 63 4.3. Optical Signal Compatibility Constraint . . . . . . . . . 9 64 4.4. switching capability . . . . . . . . . . . . . . . . . . . 10 65 5. Encoding . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 66 5.1. Label Set . . . . . . . . . . . . . . . . . . . . . . . . 10 67 5.2. Flexible-Grid Ability and Switching Cpability 68 Constraint . . . . . . . . . . . . . . . . . . . . . . . . 14 69 5.3. Optical Signal Compatibility Constraint . . . . . . . . . 16 70 6. Encoding Example . . . . . . . . . . . . . . . . . . . . . . . 17 71 6.1. Example of Label Set Encoding . . . . . . . . . . . . . . 17 72 6.2. Example of Flexible-Grid Ability Constraint Encoding . . . 20 73 6.3. Example of Signal Compatibility Encoding . . . . . . . . . 20 74 7. Security Considerations . . . . . . . . . . . . . . . . . . . 21 75 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 21 76 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 21 77 9.1. Normative References . . . . . . . . . . . . . . . . . . . 21 78 9.2. Informative References . . . . . . . . . . . . . . . . . . 21 79 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 22 81 1. Introduction 83 Flexible-Grid technique breaks the rigid nature of traditional DWDM 84 wavelength Grid, and enables flexible allocation of optical spectrum 85 resources to accommodate ultra-high data rate traffic. In such 86 environments, Network elements (such as nodes and Optical-to- 87 Electronic/Electronic-to-Optical sub-systems) and links may impose 88 additional routing constraints such as available frequency range, 89 flexible-grid ability and slot width range on ports/links, asymmetric 90 switch connectivity, signal processing limitations of each OE/EO 91 system, and so on. Without considering these constraints, it cannot 92 be guaranteed to obtain available results in RSA process especially 93 for network scenarios with various Flexible-Grid and Fixed-Grid 94 elements, which leads to inefficient routing and high blocking 95 probability of end-to-end paths. 97 This document describes the requirments of RSA, and then encodes the 98 constraints imposed by network elements and links, which could be 99 carried in OSPF Messages to flood to each node for efficient RSA. In 100 addition, such information could be conveyed by other mechanisms to a 101 Path Computation Element (PCE). Note that, impairment-related 102 constraints are not considered here. 104 2. Conventions Used in This Document 106 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 107 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 108 document are to be interpreted as described in [RFC2119]. 110 3. Terminologies 112 Center Frequency Granularity (CFG): The minimum step by which the 113 center frequency of optical bandwidth can be increased or decreased. 114 . 116 frequency grid: A frequency grid is a reference set of frequencies 117 used to denote allowed nominal central frequencies that may be used 118 for defining applications. 120 Frequency slot: The frequency range allocated to a slot and 121 unavailable to other slots within a flexible grid. A frequency slot 122 is defined by its nominal central frequency and its slot width 123 [G.694.1v2]. 125 [Editor's note: according to ITU-T WP3 Q12 interim meeting [ITU-T 126 WD12R2], one or multiple Optical Channels may be transported over a 127 single frequency slot. If this viewpoint is accepted, the following 128 definitions are needed: 130 Single-Channel Frequency Slot: a frequency slot associated with a 131 single optical channel signal (that carries a single OCh payload). 133 Multi-Channel Frequency Slot: a frequency slot associated with 134 multiple optical channel signals (i.e. multiple OChs).] 136 Frequency Slot Channel: a topological construct that represents a 137 piece of spectrum supported by a concatenation of media elements 138 (fiber, amplifiers, filters..). This term is used to identify the 139 end-to-end physical layer entity with its corresponding (one or more) 140 frequency slots local at each link. 142 GMPLS: Generalized Multi-Protocol Label Switching. 144 Lowest/Highest frequency: the lowest/highest frequency of a frequency 145 slot. 147 OCH: Optical Channel 149 ROADM: Reconfigurable Optical Add-Drop Multiplexer. 151 RSA: Routing and spectrum assignment. 153 Slice: the basic slot unit, and the slot width of one slice is equal 154 to slot width granularity. 156 Slot width: The full width of a frequency slot in a flexible grid 157 [G.694.1v2]. 159 Slot Width Granularity (SWG): the minimum step by which the optical 160 filter bandwidth of ROADM can be increased or decreased. 161 Accordingly, SWG (GHz) = 2 * CFG (GHz). 163 WSON: Wavelength Switched Optical Networks [RFC6163]. 165 WSS: Wavelength Selective Switch. 167 4. Requirements of Routing Constraint for RSA in Flexible-Grid Networks 169 In Flexible-Grid network, there is one key problem: how to route and 170 allocate spectrum resources for each end-to-end optical channel, so 171 to fulfill their requirements in an efficient way? To address this 172 problem, some constraints must be taken into consideration, which are 173 listed as follows. 175 -Spectrum availability constraint. 177 -Flexible-Grid ability constraint. 179 -Asymmetric switch connectivity constraint. 181 -Optical signal compatibility constraint. 183 -Other constraints. 185 The asymmetric switch connectivity constraint in Flexible-Grid 186 network could be well addressed by Connectivity matrix sub-TLV used 187 in Wavelength Switched Optical Networks (WSON) 188 [I-D.ietf-ccamp-general-constraint-encode]. The spectrum 189 availability constraint is studied in several drafts 190 [I-D.li-ccamp-flexible-grid-label] 191 [I-D.zhang-ccamp-flexible-grid-ospf-ext][I-D.dhillon-ccamp-super-chan 192 nel-ospfte-ext], and could be represented by Label-set extensions. 193 However, these extensions are not complete, so we reorganize the 194 Flexible-Grid label-set according to WSON definition. In addition, 195 Flexible-Grid ability constraint (icluding grid type and slot width 196 granularity/range) and optical signal conpatibility constraint are 197 also necessary for efficient RSA, but few document takes these into 198 account. we will describe the requirements and encodings of such 199 constraints in this draft. 201 Here a general scenario of Flexible-Grid Network is given in order to 202 illustrate these requirements. 204 +----+A-E2 B-I1+----+B-E2 C-I1+----+ 205 | A |----------->| B |----------->| C | 206 | |<-----------| |<-----------| | 207 +----+A-I2 B-E1+----+B-I2 C-E1+----+ 208 O| O| O| 209 A-I1||A-E1 B-I3||B-E3 C-I2||C-E2 210 || || || 211 || || || 212 || || || 213 || || || 214 D-E1||D-I1 E-E3||E-I3 F-E2||F-I2 215 |O |O |O 216 +----+D-E2 E-I1+----+E-E2 F-I1+----+ 217 | D |----------->| E |----------->| F | 218 | |<-----------| |<-----------| | 219 +----+D-I2 E-E1+----+E-I2 F-E1+----+ 221 Figure 1. A sample network with both Fixed-Grid and Flexible-Grid 222 elements 224 Tributary Side: E5 I5 E6 I6 225 O | O | 226 | | | | 227 | O | O 228 +-----------------------+ 229 |+-----+ +-----+| 230 Line side-1 --->||Split| |WSS-2||---> Line side-2 231 Input (I1) |+-----+ +-----+| Output (E2) 232 Line side-1 <---||WSS-1| |Split||<--- Line side-2 233 Output (E1) |+-----+ +-----+| Input (I2) 234 | ROADM | 235 |+-----+ +-----+| 236 Line side-3 --->||Split| |WSS-4||---> Line side-4 237 Input (I3) |+-----+ +-----+| Output (E4) 238 Line side-3 <---||WSS-3| |Split||<--- Line side-4 239 Output (E3) |+-----+ +-----+| Input (I4) 240 +-----------------------+ 241 | O | O 242 | | | | 243 O | O | 244 Tributary Side: E7 I7 E8 I8 246 Figure 2. A ROADM Composed of WSSs and splitters (Internal 247 connections are not presented) 249 Figure 1 shows the network topology, while Figure 2 shows the 250 architecture of nodes. The ROADM of Figure 2 is composed of WSSs and 251 splitters. I1~4/E1~4 are line-side input/output ports, while I5~8/ 252 E5~8 are tributary-side add/drop ports to/from line-side 1~4 253 respectively. The configuration of each line-side output port is 254 shown as follows: 256 +----+---------+-----+------+-----------+---------+---------+ 257 |Node|Node-Type|Ports| Type |Granularity|Min width|Max width| 258 +----+---------+-----+------+-----------+---------+---------+ 259 | | |A-E1 | Flex | 25GHz | 50GHz | 300GHz | 260 | A | Flex |-----+------+-----------+---------+---------+ 261 | | |A-E2 | Flex | 12.5GHz | 50GHz | 200GHz | 262 +----+---------+-----+------+-----------+---------+---------+ 263 | | |B-E1 | Flex | 12.5GHz | 50GHz | 200GHz | 264 | | |-----+------+-----------+---------+---------+ 265 | B | Mixed |B-E2 | Fixed| 50GHz | 50GHz | 50GHz | 266 | | |-----+------+-----------+---------+---------+ 267 | | |B-E3 | Flex | 12.5GHz | 50GHz | 200GHz | 268 +----+---------+-----+------+-----------+---------+---------+ 269 | | |C-E1 | Fixed| 50GHz | 50GHz | 50GHz | 270 | C | Fixed |-----+------+-----------+---------+---------+ 271 | | |C-E2 | Fixed| 50GHz | 50GHz | 50GHz | 272 +----+---------+-----+------+-----------+---------+---------+ 273 | | |D-E1 | Flex | 25GHz | 50GHz | 300GHz | 274 | D | Flex |-----+------+-----------+---------+---------+ 275 | | |D-E2 | Flex | 25GHz | 50GHz | 300GHz | 276 +----+---------+-----+------+-----------+---------+---------+ 277 | | |E-E1 | Flex | 25GHz | 50GHz | 300GHz | 278 | | |-----+------+-----------+---------+---------+ 279 | E | Flex |E-E2 | Flex | 12.5Ghz | 50GHz | 200GHz | 280 | | |-----+------+-----------+---------+---------+ 281 | | |E-E3 | Flex | 12.5GHz | 50GHz | 200GHz | 282 +----+---------+-----+------+-----------+---------+---------+ 283 | | |F-E1 | Flex | 12.5GHz | 50GHz | 200GHz | 284 | F | Mixed |-----+------+-----------+---------+---------+ 285 | | |F-E2 | Fixed| 50GHz | 50GHz | 50GHz | 286 +----+---------+-----+------+-----------+---------+---------+ 288 The granularity denotes the slot width granularity. The Min-width 289 and Max-width denote the slot width range. There are three types of 290 nodes: Node A, node D and node E are Flexible-Grid ROADMs, which only 291 consist of Flexible-Grid elements; Node C is a Fixed-Grid ROADM, 292 which only consists of Fixed-Grid elements; Node B and Node F are 293 Mixed-Grid ROADMs, which consist of both Flexible-Grid and Fixed-Grid 294 Elements. Both Flexible-Grid ROADM and Mixed-Grid ROADM can support 295 Flexible-Grid LSPs to accommodate ultra-high data rate traffic such 296 as beyond 100G. In addition, the Fixed-Grid ROADM can be smoothly 297 updated to Mixed-Grid ROADM by adding Flexible-Grid ports. With 298 appropriate RSA, the network is able to support both Fixed-Grid LSPs 299 and Flexible-Grid LSPs in an efficient way. 301 4.1. Label set 303 In Flexible-Grid networks, the spectrum assignment is not a local 304 matter due to spectral consecutiveness and continuity constraints, so 305 it is needed to get the information of which slice may or may not be 306 used on each link and node port along the path in RSA process. For 307 example, in the network of Figure 1, when a LSP request from node A 308 to node E with 150GHz slot width and route A->B->E arrives, the label 309 restriction of input port A-I6, output port E-E7, switch port A-E2, 310 B-I1, B-E3, E-I3 and spectrum availability of link AB, BE must be got 311 for the spectrum assignment. All the information is described by the 312 label set objects which is decided by the label format. The 313 generalized label for the flexible grid can be referred to 314 [I-D.farrkingel-ccamp-flexigrid-lambda-label] including central 315 frequency and slot width information. 317 As specified in [I-D.li-ccamp-flexible-grid-label] in section 4.1, 318 this kind of label format is backward compatible to support the 319 traditional 5 ways of wavelength label set encoding 320 [I-D.ietf-ccamp-general-constraint-encode]. 322 o 1. Inclusive list 324 o 2. Exclusive list 326 o 3. Inclusive range 328 o 4. Exclusive range 330 o 5. Bitmap set 332 It can be seen that these 5 types of representations can be easily 333 inherited by incorporating the new flexible label into the object. 334 Note that in the procedure of flooding, any combination of the 5 335 types of label sets is feasible. 337 4.2. Flexible-Grid Ability Constraint 339 Flexible-Grid ability may include the grid type (Fixed-Grid or 340 Flexible-Grid) and slot width granularity/range. This information 341 can be seen as the attribution of network ports with relations to 342 links or nodes. The RSA requirements of such fields are listed as 343 follows: 345 Firstly, Flexible-Grid WSSs of different companies or product-types 346 may have different slot width granularity and range, which may be a 347 subset of possible values specified by ITU-T [G.694.1v2], so it 348 should be taken into consideration in RSA process to avoid invalid 349 route selection. For example, in the network of Figure 1, when a 350 Flexible-Grid LSP request from node A to node E with 250GHz slot 351 width arrives, only the optical channel with a route A->D->E is able 352 to carry the traffic due to the slot width range limitations on other 353 ports. 355 In addition, The slot width granularity of network elements may 356 impact the spectral efficiency. For example, when a Flexible-Grid 357 LSP request from node A to node E with 87.5GHz slot width arrives, 358 100GHz Slot width must be assigned for the route A->D->E due to 25GHz 359 slot width granularity, which performs poor in spectral efficiency. 361 FurthermoreGBP[not]Although Flexible-Grid technology may offer full 362 backwards compatibility with the standard ITU-T DWDM grids, it is a 363 cost-efficient way to consider Flexible-Grid Ability constraints in 364 RSA process for Fixed-Grid requirements. For example, in the network 365 of figure 1, when a Fixed-Grid LSP request from node B to node F with 366 50GHz slot width arrives, it is a better route of B->C->F than the 367 route B->E->F, because that flexible-Grid WSSs are more expensive 368 than fixed-grid ones, and routing fixed-Grid requests on fixed-Grid 369 elements could leave the Flexible-Grid elements and related spectrum 370 resources to subsequent high data rate traffic. 372 4.3. Optical Signal Compatibility Constraint 374 Optical Signal Compatibility Constraint includes the signal 375 processing ability (for example, data rate, FEC and modulation 376 format) and modulation-related minimum slot width for each Optical- 377 to-Electronic (OE)/Electronic-to-Optical (EO) subsystem. The RSA 378 requirements of such fields are listed as follows: 380 Firstly, as described in [I-D.ietf-ccamp-rwa-wson-encode], OE/EO 381 subsystems may be limited to process only certain types of optical 382 signal in WSON or Flexible-Grid networks, so it is necessary to get 383 sufficient information characterizing OE/EO elements in RSA process 384 to determine the signal compatibility along the path. Examples of 385 such subsystems include transponders, regenerators and so on. 387 In addition, for each Flexible-Grid Label Switch Path, the required 388 slot width is determined by the attribution of optical signal. 389 However, a client only requests "data rate" as its traffic parameter 390 but do not care "slot width", so it is needed to establish the 391 mapping relations between data-rate/modulation-format and slot width, 392 which should be reflected in optical signal compatibility constraint. 393 For example, in the network of Figure 1, when a LSP request from node 394 A to Node E with 100Gbit/s data rate arrives, and both the 395 transmitter of node A and the responder of node E support optical 396 tributary signal class DP-QPSK 100G with the same FEC and 397 corresponding slot width 50GHz, the minimum slot width required by 398 this LSP should be 50GHz. 400 4.4. switching capability 402 According to ITU-T WP3 Q12 interim meeting [ITU-T WD12R2], the media 403 layer corresponds to the server layer (flexigrid) and the signal 404 layer corresponds to the client layer (OCh).this means the separation 405 between the signal and the waveguide that the signal propagates 406 through. For example, one frequency slot channel setup in media 407 layer could be seen as a TE-link in signal layer, and carry one 408 (single-channel frequency slot) or multiple (multiple-channel 409 frequency slot) OCh. 411 For control plane, it needs to differentiate signal LSP (OCh) and 412 media LSP (frequency-slot channel), and specify the switching 413 capability (signal/media) of each interface/TE-link. 415 5. Encoding 417 5.1. Label Set 419 The general format for a label set is in accordance with that in 420 [I-D.ietf-ccamp-general-constraint-encode], with a new flag G (1bit) 421 representing the grid type of label sets(1~Flexible-Grid DWDM; 422 0~Fixed-Grid DWDM): 424 0 1 2 3 425 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 1 426 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 427 |G| Act.| Num Labels | Length | 428 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 429 | start Label | 430 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 431 | start Label(continue) | 432 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 433 : Additional fields as necessary per action : 434 : : 435 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 437 the label format is in accordance with that in 438 [I-D.farrkingel-ccamp-flexigrid-lambda-label]. 440 In the case of Inclusive/Exclusive label lists (0/1), the label set 441 format is given as follows: 443 0 1 2 3 444 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 1 445 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 446 |1| 0or1| Num Labels (not used) | Length | 447 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 448 | First Label | 449 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 450 | First Label(continue) | 451 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 452 : : 453 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 454 | Last Label | 455 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 456 | Last Label(continue) | 457 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 459 Note that one label set may contain multiple labels. The lowest/ 460 highest frequency of the K-th label is calculated as follows: 462 Lowest frequency_k = (central frequency_k) - (slot width_k)/2 464 = (193.1 + n_k * C.S.) - (2 * C.S. * m_k)/2 466 = (193.1 + (n_k - m_k) * C.S.) THz; 468 Highest frequency_k = Lowest frequency_k + slot width_k 470 = (193.1 + (n_k + m_k) * C.S.) THz; 472 In the case of Inclusive/Exclusive label ranges (2/3), the label set 473 format is given as follows: 475 0 1 2 3 476 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 1 477 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 478 |1| 2or3| Num Labels(not used) | Length | 479 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 480 | Start Label #1 | 481 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 482 | Start Label #1(continue) | 483 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 484 | End Label #1 | 485 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 486 | End Label #1(continue) | 487 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 488 : : 489 : : 490 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 491 | Start Label #n | 492 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 493 | Start Label #n(continue) | 494 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 495 | End Label #n | 496 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 497 | End Label #n(continue) | 498 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 500 Note that one label set may contain multiple label ranges. The value 501 of m in start/end label in meaningless on the label set, however, in 502 order to keep the integrity of labels and avoid misunderstanding, it 503 is set to default value: m = (slot width granularity)/12.5GHz. 505 The lowest/highest frequency of the K-th label range is calculated as 506 follows: 508 Lowest frequency_k = (central frequency_kstart) - (slot width 509 granularity)/2 511 = (193.1 + n_kstart * C.S.) - C.S. 513 = (193.1 + (n_kstart - 1) * C.S.) THz; 515 Highest frequency_k = (central frequency_kend) + (slot width 516 granularity)/2 518 = (193.1 + n_kend * C.S.) + C.S. 520 = (193.1 + (n_kend + 1) * C.S.) THz; 521 In the case of bitmap (4), the label set format is given as follows: 523 0 1 2 3 524 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 1 525 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 526 |1| 4 | Num Labels | Length | 527 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 528 | Start Label | 529 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 530 | Start Label(continue) | 531 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 532 | Bit Map Word #1 (Lowest numerical labels) | 533 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 534 : : 535 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 536 | Bit Map Word #N (Highest numerical labels) | 537 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 539 Based on [I-D.ietf-ccamp-general-constraint-encode], Num labels 540 denote the number of slices represented by the bit map; where the 541 slice denotes the basic slot unit, and the slot width of one slice is 542 equal to the slot width granularity. As there may exist some 543 situations that the unused bandwidth between two occupied bandwidth 544 is odd times of the central frequency granularity (not integral times 545 of the slot with granularity), two bits are needed to represent a 546 single slice. Each bit in the bit map represents a particular label 547 of half a slice with a value of 1/0 indicating whether the part is in 548 the set or not. Bit position zero and one represent the lowest slice 549 and corresponds to the start label. The lowest/highest frequency of 550 label range represented by bit position K is calculated as follows: 552 Lowest frequency_k = (central frequency_start) + (K - 1) * (slot 553 width granularity)/2 555 = (193.1 + n_start * C.S.) + (K - 1) * C.S. 557 = 193.1 + (n_start + K -1) * C.S.; 559 Highest frequency_k = Low frequency_k + C.S. 561 = 193.1 + (n_start + K) * C.S. 563 The size of the bit map is (2 * Num Label) bits, but the bit map is 564 padded out to a full multiple of 32 bits so that the TLV is a 565 multiple of four bytes. "Bits that do not represent labels (i.e., 566 those in positions) and beyond SHOULD be set to zero and MUST be 567 ignored" [I-D.ietf-ccamp-general-constraint-encode]. 569 5.2. Flexible-Grid Ability and Switching Cpability Constraint 571 To accommodate the feature of Flexible-Grid Ability and switching 572 capability constraint, we extend the Port Label Restriction sub-TLV 573 defined in [I-D.ietf-ccamp-general-constraint-encode] for Flexible- 574 Grid networks: 576 0 1 2 3 577 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 1 578 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 579 | MatrixID | RstType = 5 | Switching Cap.| Encoding | 580 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 581 |Grid | C.S. |S|M|Reserved | Min-Width | Max-Width | 582 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 584 In WSON network, Matrix ID is used to represent "either the value in 585 the corresponding Connectivity Matrix sub-TLV or takes the value OxFF 586 to indicate the restriction applies to the port regardless of any 587 Connectivity Matrix" [I-D.ietf-ccamp-general-constraint-encode]. 588 RstType is used to represent the restriction type. This document 589 defines a new RstType value to express the port Flexible-Grid 590 Supporting Ability constraint in Flexible-Grid networks: 592 5: GRID_ABILITY. 594 The meaning of Grid and C.S. is defined in 595 [I-D.farrkingel-ccamp-flexigrid-lambda-label], which is shown as 596 follows: 598 +---------------+-------+ 599 | Grid | Value | 600 +---------------+-------+ 601 | Reserved | 0 | 602 +---------------+-------+ 603 | ITU-T DWDM | 1 | 604 +---------------+-------+ 605 | ITU-T CWDM | 2 | 606 +---------------+-------+ 607 | Flexible DWDM | 3 | 608 +---------------+-------+ 609 | Any | 4(TBA)| 610 +---------------+-------+ 611 | Future use | 5-7 | 612 +---------------+-------+ 614 +-------------+---------+ 615 |C.S. (GHz) | Value | 616 +-------------+---------+ 617 | Reserved | 0 | 618 +-------------+---------+ 619 | 100 | 1 | 620 +-------------+---------+ 621 | 50 | 2 | 622 +-------------+---------+ 623 | 25 | 3 | 624 +-------------+---------+ 625 | 12.5 | 4 | 626 +-------------+---------+ 627 | 6.25 | 5 (TBA) | 628 +-------------+---------+ 629 |Future use | 6 ~ 15 | 630 +-------------+---------+ 632 A new Grid type "Any" is defined. the reason is explained later in 633 this document. 635 "Within the fixed grid network, the C.S. value is used to represent 636 the channel spacing, as the spacing between adjacent channels is 637 constant. While for flexible grid situation, this field should be 638 used to represent central frequency granularity." 639 [I-D.farrkingel-ccamp-flexigrid-lambda-label] Accordingly the slot 640 width granularity is twice of the C.S.. 642 Min-Width/Max-Width: 8bits, unsigned integer. Min-Width/Max-Width 643 denotes the minimum/maximum slot width that the ROADM port supports, 644 which is an inherent attribution of the network elements. The 645 formula is shown as follows: 647 Minimum Slot Width (GHz) = 12.5GHz * Min-Width; 649 Maximum Slot Width (GHz) = 12.5GHz * Max-Width; 651 For flexible-Grid ports (Grid = 3), the possible values of slot width 652 are within the range [Minimum Slot Width, Maximum Slot Width] and 653 with the slot width granularity of 2 * C.S.; for Fixed-Grid ports 654 (Grid = 1 or 2), Min-Width/Max-Width is meaningless and padded with 655 0. For any port with Grid type "any", it means that the port support 656 any Grid type, any slot width granularity and any slot width range, 657 so C.S. and Min-Width/Max-Width are meaningless and padded with 0. 658 One example of such port is A-I1, which is comprised of optical 659 splitter. 661 Note that, the similar field of Min-Width/Max-Width is also included 662 in object "BW sub-TLV" proposed by 663 [I-D.dhillon-ccamp-super-channel-ospfte-ext]. However, BW sub-TLV is 664 mainly used to present the available label set, so it belongs to 665 dynamic information according to [RFC6163] and should be flooded 666 frequently whenever the link state changes (for example, after the 667 setup/teardown of the path traversing the link). In this document, 668 the Port Label Restriction sub-TLV with GRID_ABILITY type is regarded 669 as relatively static information, as changes to these properties such 670 as Grid, C.S. and Min-Width/Max-Width require hardware upgrades. It 671 is more suitable to carry such information separated from available 672 label set in order to alleviate unnecessary flooding. 674 A new switching capability is defined here: 151, Spectrum Switch 675 Capable (SSC). When the switching capability is SSC, the field S 676 indicates the signal-layer switch capability (1-support, 0-not), 677 while the field M indicates the media-layer switch capability 678 (1-support, 0-not). 680 Other port label restrictions have no difference with that in 681 [I-D.ietf-ccamp-general-constraint-encode]. 683 5.3. Optical Signal Compatibility Constraint 685 To accommodate the feature of Optical Signal Compatibility 686 Constraint, we extend the Modulation Type sub-TLV defined in 687 [I-D.ietf-ccamp-rwa-wson-encode] for Flexible-Grid networks: 689 0 1 2 3 690 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 1 691 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 692 |S|I| Modulation ID | Length | 693 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 694 | m | Possible additional modulation parameters | 695 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 696 : the modulation ID : 697 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 699 The meaning of S, I and Modulation ID is in accordance with that of 700 [I-D.ietf-ccamp-rwa-wson-encode]. 702 This document adds a new field "m" (8bit) to represent the minimum 703 slot width requirement for corresponding Modulation ID: 705 Minimum Slot Width = 12.5GHz * m. 707 Note that the modulation type sub-TLV may contain multiple modulation 708 IDs, which means the transmitter/responder/transponder/regennerator 709 support multiple data rate/modulation format. 711 This sub-TLV establishes mapping relations between data rate/ 712 modulation format (Modulation ID) and slot width. In addition, it 713 also provides the signal processing ability for each OE/EO element in 714 the network. However, FEC may impact the value of m, but it is not 715 discussed here and leaved for further study. New values of 716 Modulation ID should be defined for ultra-high speed transmission, 717 but it depends on transmission technique and not specified in this 718 document. 720 Other signal compatibility constraints have no difference with that 721 in [I-D.ietf-ccamp-rwa-wson-encode]. 723 6. Encoding Example 725 6.1. Example of Label Set Encoding 727 Taking the network of figure 1 as an example, the available spectral 728 resource of link AB is shown in figure 3. 730 #1 Lowest #2 Highest #3 731 |-|-| |---------|---------| |-------|-------| 732 | |Center Freq. | ^ 733 |1 1 0 0 1 1 1 1 1 1 1 1 1 1 0 0 0 0 1 1 1 1 1 1 1 1| 734 __|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|__ 735 n= -16 -14 -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 736 | |___| 737 |_|_| 12.5GHz 738 | 739 slice 741 Figure 3. Spectral resource state of link AB 743 In figure 3, the spectral resource is from 193.1THz - 16 * 6.25GHz to 744 193.1THz + 10 * 6.25GHz. For label list type, the label set format 745 is given as follows: 747 0 1 2 3 748 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 1 749 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 750 |1| 0 | Num Labels(not used) | Length(28) | 751 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 752 | 3 |C.S.(5)| Identifier | n(-15) | 753 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 754 | m(1) | Reserved | 755 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 756 | 3 |C.S.(5)| Identifier | n(-7) | 757 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 758 | m(5) | Reserved | 759 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 760 | 3 |C.S.(5)| Identifier | n(6) | 761 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 762 | m(4) | Reserved | 763 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 765 For label range type, the label set format is given as follows: 767 0 1 2 3 768 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 1 769 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 770 |1| 2 | Num Labels(not used) | Length(52) | 771 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 772 | 3 |C.S.(5)| Identifier | n(-15) | 773 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 774 | m(1) | Reserved | 775 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 776 | 3 |C.S.(5)| Identifier | n(-15) | 777 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 778 | m(1) | Reserved | 779 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 780 | 3 |C.S.(5)| Identifier | n(-11) | 781 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 782 | m(1) | Reserved | 783 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 784 | 3 |C.S.(5)| Identifier | n(-3) | 785 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 786 | m(1) | Reserved | 787 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 788 | 3 |C.S.(5)| Identifier | n(3) | 789 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 790 | m(1) | Reserved | 791 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 792 | 3 |C.S.(5)| Identifier | n(9) | 793 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 794 | m(1) | Reserved | 795 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 797 For bitmap type, the label set format is given as follows: 799 0 1 2 3 800 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 1 801 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 802 |1| 4 | Num Labels(26) | Length(16) | 803 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 804 | 3 |C.S.(5)| Identifier | n(-15) | 805 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 806 | m(1) | Reserved | 807 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 808 |1|1|0|0|1|1|1|1|1|1|1|1|1|1|0|0|0|0|1|1|1|1|1|1|1|1|0|0|0|0|0|0| 809 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 811 6.2. Example of Flexible-Grid Ability Constraint Encoding 813 Taking the network of figure 1 as an example, the Flexible-Grid 814 ability constraint of A-E1 can be encoded as follows: 816 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 1 817 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 818 | MatrixID(0xff)| RstType(5) | Reserved | 819 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 820 | 3 |C.S.(5)| Reserved | Min-Width(4) | Max-Width(16) | 821 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 823 The Flexible-Grid ability constraint of A-E2 can be encoded as 824 follows: 826 0 1 2 3 827 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 1 828 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 829 | MatrixID(0xff)| RstType(5) | Reserved | 830 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 831 | 3 |C.S.(4)| Reserved | Min-Width(4) | Max-Width(24) | 832 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 834 The Flexible-Grid ability constraint of B-E2 can be encoded as 835 follows: 837 0 1 2 3 838 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 1 839 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 840 | MatrixID(0xff)| RstType(5) | Reserved | 841 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 842 | 1 |C.S.(2)| Reserved | Min-Width(0) | Max-Width(0) | 843 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 845 6.3. Example of Signal Compatibility Encoding 847 Assuming an optical transmitter can support the following modulation 848 types: optical tributary signal class DP-QPSK 100G (minimum slot 849 width: 50GHz); optical tributary signal class DP-BPSK 100G (minimum 850 slot width: 100GHz). T he Modulation Type sub-TLV is given as 851 follows: 853 0 1 2 3 854 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 1 855 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 856 |1|0| DP-QPSK 100G | Length(8) | 857 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 858 | m(4) | Possible additional modulation parameters | 859 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 860 |1|0| DP-BPSK 100G | Length(8) | 861 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 862 | m(8) | Possible additional modulation parameters | 863 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 865 7. Security Considerations 867 8. IANA Considerations 869 TBD. 871 9. References 873 9.1. Normative References 875 [G.694.1v2] 876 ITU-T Recommendation G.694.1, "Spectral grids for WDM 877 apllications: DWDM frequency grid", November 2011. 879 [ITU-T WD12R2] 880 International Telecomunications Union, WD12R2, Q12-SG15, 881 "Proposed media layer terminology for G.872", May 2012. 883 [RFC2119] Bradner, S., "Key words for use in RFC's to Indicate 884 Requirement Levels", RFC 2119, March 1997. 886 [RFC6163] Lee, Y., Bernstain, G., and W. Imajuku, "Framework for 887 GMPLS and Path Computation Element Control of Wavelength 888 Switched Optical Networks", RFC 6163, April 2011. 890 9.2. Informative References 892 [I-D.dhillon-ccamp-super-channel-ospfte-ext] 893 Dhillon, A., Hussain, I., Rao, RJ., and M. Sosa, "OSPFTE 894 extension to support GMPLS for Flex Grid", October 2011. 896 [I-D.farrkingel-ccamp-flexigrid-lambda-label] 897 Farrel, A., King, D., Li, Y., Zhang, F., and R. Casellas, 898 "Generalized Labels for the Flexi-Grid in Lambda-Switch- 899 Capable (LSC) Label Switching Routers", October 2011. 901 [I-D.hussain-ccamp-super-channel-label] 902 Hussain, I., Dhillon, A., Pan, Z., Sosa, M., Basch, B., 903 Liu, S., and A-G. Malis, "Generalized Label for Super- 904 Channel Assignment on Flexible Grid", October 2011. 906 [I-D.ietf-ccamp-general-constraint-encode] 907 Bernstein, G., Lee, Y., Li, D., Imajuku, W., and JR. Han, 908 "General Network Element Constraint Encoding for GMPLS 909 Controlled Networks", May 2011. 911 [I-D.ietf-ccamp-rwa-wson-encode] 912 Bernstein, G., Lee, Y., Li, D., Imajuku, W., and JR. Han, 913 "Routing and Wavelength Assignment Information Encoding 914 for Wavelength Switched Optical Networks", October 2011. 916 [I-D.li-ccamp-flexible-grid-label] 917 Li, Y., Zhang, F., and R. Casellas, "Flexible Grid Label 918 Format in Wavelength Switched Optical Network", July 2011. 920 [I-D.zhang-ccamp-flexible-grid-ospf-ext] 921 Zhang, FT., Zi, XB., Casellas, R., Gonzales-de-Dios, O., 922 and D. Ceccarelli, "GMPLS OSPF-TE Extensions in support of 923 Flexible-Grid in DWDM Networks", October 2011. 925 [I-D.zhang-ccamp-flexible-grid-requirements] 926 Zhang, FT., Zi, XB., Gonzales-de-Dios, O., and R. 927 Casellas, "Requirements for GMPLS Control of Flexible 928 Grids", October 2011. 930 [I-D.zhang-ccamp-flexible-grid-rsvp-te-ext] 931 Zhang, FT., Gonzales-de-Dios, O., and D. Ceccarelli, 932 "RSVP-TE Signaling Extensions in support of Flexible 933 Grid", October 2011. 935 [I-D.zhangj-ccamp-flexi-grid-ospf-te-ext] 936 Zhang, J., Zhao, YL., and ZY. Yu, "OSPF-TE Protocol 937 Extension for Constraint-aware RSA in Flexi-Grid 938 Networks", October 2011. 940 Authors' Addresses 942 Lei Wang 943 ZTE 944 No.19, Huayuan East Road, Haidian District 945 Beijing 100191 946 P.R.China 948 Phone: +86 13811440067 949 Email: wang.lei131@zte.com.cn (hechen0001@gmail.com) 950 URI: http://www.zte.com.cn/ 952 Yao Li 953 ZTE 954 P.R.China 956 Phone: +86 025 52871109 957 Email: li.yao3@zte.com.cn 958 URI: http://www.zte.com.cn/ 960 Guoying Zhang 961 China Academy of Telecom Research, MIIT 962 No.52 Huayuan Beilu, Haidian District 963 Beijing 100083 964 P.R.China 966 Email: zhangguoying@mail.ritt.com.cn