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Checking references for intended status: Informational ---------------------------------------------------------------------------- -- Obsolete informational reference (is this intentional?): RFC 7752 (Obsoleted by RFC 9552) Summary: 0 errors (**), 0 flaws (~~), 1 warning (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Common Control and Measurment Plane I. Hussain 3 Internet-Draft R. Valiveti 4 Intended status: Informational Infinera Corp 5 Expires: May 3, 2018 Q. Wang 6 ZTE 7 L. Andersson 8 M. Chen 9 H. Zheng 10 Huawei 11 October 30, 2017 13 GMPLS Routing and Signaling Framework for Flexible Ethernet (FlexE) 14 draft-izh-ccamp-flexe-fwk-04 16 Abstract 18 This document specifies GMPLS control plane requirements, framework, 19 and architecture for FlexE technology. 21 As different from earlier Ethernet data planes FlexE allows for 22 decoupling of the Ethernet Physical layer (PHY) and Media Access 23 Control layer (MAC) rates. 25 Study Group 15 (SG15) of the ITU-T has endorsed the FlexE 26 Implementation Agreement from Optical Internetworking Forum (OIF) and 27 included it, by reference, in some of their Recommendations. 29 Status of This Memo 31 This Internet-Draft is submitted in full conformance with the 32 provisions of BCP 78 and BCP 79. 34 Internet-Drafts are working documents of the Internet Engineering 35 Task Force (IETF). Note that other groups may also distribute 36 working documents as Internet-Drafts. The list of current Internet- 37 Drafts is at https://datatracker.ietf.org/drafts/current/. 39 Internet-Drafts are draft documents valid for a maximum of six months 40 and may be updated, replaced, or obsoleted by other documents at any 41 time. It is inappropriate to use Internet-Drafts as reference 42 material or to cite them other than as "work in progress." 44 This Internet-Draft will expire on May 3, 2018. 46 Copyright Notice 48 Copyright (c) 2017 IETF Trust and the persons identified as the 49 document authors. All rights reserved. 51 This document is subject to BCP 78 and the IETF Trust's Legal 52 Provisions Relating to IETF Documents 53 (https://trustee.ietf.org/license-info) in effect on the date of 54 publication of this document. Please review these documents 55 carefully, as they describe your rights and restrictions with respect 56 to this document. Code Components extracted from this document must 57 include Simplified BSD License text as described in Section 4.e of 58 the Trust Legal Provisions and are provided without warranty as 59 described in the Simplified BSD License. 61 Table of Contents 63 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 64 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 4 65 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 66 3. FlexE Reference Model . . . . . . . . . . . . . . . . . . . . 5 67 4. Requirements . . . . . . . . . . . . . . . . . . . . . . . . 6 68 5. GMPLS Controlled FlexE . . . . . . . . . . . . . . . . . . . 7 69 5.1. Types of LSPs in a FlexE capable network . . . . . . . . 8 70 5.2. Signaling Channel . . . . . . . . . . . . . . . . . . . . 8 71 5.3. MPLS LSP in the FlexE Data Plane . . . . . . . . . . . . 8 72 5.4. Configuring the data plane in FlexE capable nodes . . . . 10 73 5.4.1. Configure/Establish a FlexE Group/Link . . . . . . . 10 74 5.4.2. Configure/Establish a FlexE Client . . . . . . . . . 11 75 5.4.3. Advertise FlexE Groups and FlexE lts . . . . . . . . 11 76 6. Framework and Architecture . . . . . . . . . . . . . . . . . 11 77 6.1. FlexE Framework . . . . . . . . . . . . . . . . . . . . . 12 78 6.2. FlexE Architecture . . . . . . . . . . . . . . . . . . . 12 79 6.2.1. Architecture Components . . . . . . . . . . . . . . . 12 80 6.2.2. FlexE Layer Model . . . . . . . . . . . . . . . . . . 12 81 6.2.2.1. FlexE Group structure . . . . . . . . . . . . . . 13 82 6.2.2.2. FlexE Client mapping . . . . . . . . . . . . . . 13 83 7. Control Plane . . . . . . . . . . . . . . . . . . . . . . . . 13 84 7.1. GMPLS Routing . . . . . . . . . . . . . . . . . . . . . . 14 85 7.2. GMPLS Signaling . . . . . . . . . . . . . . . . . . . . . 14 86 7.2.1. LSP setu with pre-configured FlexE infrastructure . . 15 87 7.2.2. LSP setup with partially configured FlexE 88 infrastructure . . . . . . . . . . . . . . . . . . . 16 89 7.2.3. LSP setup with non-configured FlexE infrastructure . 17 90 7.2.4. Packet Label Switching Data Plane . . . . . . . . . . 17 91 8. Operations, Administration, and Maintenance (OAM) . . . . . . 19 92 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 19 93 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19 94 11. Security Considerations . . . . . . . . . . . . . . . . . . . 19 95 12. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 19 96 13. References . . . . . . . . . . . . . . . . . . . . . . . . . 19 97 13.1. Normative References . . . . . . . . . . . . . . . . . . 19 98 13.2. Informative References . . . . . . . . . . . . . . . . . 20 99 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 21 101 1. Introduction 103 Ethernet MAC rates were until recently constrained to match the rates 104 of the Ethernet PHY(s). Work within the OIF allows MAC rates to be 105 different from PHY rates. An OIF implementation agreement 106 [OIFFLEXE1] allows for complete decoupling of the MAC and PHY rates. 108 SG15 in ITU-T has endorsed the OIF FlexE data plane and parts of 109 [G.872], [G.709], [G.798] and [G.8021] depends on or are based on the 110 FlexE data plane. 112 This includes support for: 114 a. MAC rates which are greater than the rate of a single PHY; 115 multiple PHYs are bonded to achieve this 117 b. MAC rates which are less than the rate of a PHY (sub-rate) 119 c. support for channelization within a single PHY, or over a group 120 of bonded PHYs. 122 The capabilities supported by the first version of the FlexE data 123 plane are: 125 a. Support a large rate Ethernet MAC over bonded Ethernet PHYs, e.g. 126 supporting a 200G MAC over 2 bonded 100GBASE-R PHY(s) 128 b. Support a sub-rate Ethernet MAC over a single Ethernet PHY, e.g. 129 supporting a 50G MAC over a 100GBASE-R PHY 131 c. Support a collection of flexible Ethernet clients over a single 132 Ethernet PHY, e.g. supporting two MACs with the rates 25G, and 133 one with rate 50G over a single 100GBASE-R PHY 135 d. Support a sub-rate Ethernet MAC over bonded PHYs, e.g. supporting 136 a 150G Ethernet client over 2 bonded 100GBASE-R PHY(s) 138 e. Support a collection of Ethernet MAC clients over bonded Ethernet 139 PHYs, e.g. supporting a 50G, and 150G MAC over 2 bonded Ethernet 140 PHY(s) 142 Networks which support FlexE Ethernet interfaces include a basic 143 building block, this is true also when the interfaces are bonded. 144 This building block consists of two FlexE Shim functions, located at 145 opposite ends of a link, and the logical point to point links that 146 carry the Ethernet PHY signals between the two FlexE Shim Functions. 148 These logical point-to-point links may be realized in a variety of 149 ways: 151 a. direct point-to-point links with no intervening transport 152 network. 154 b. Ethernet PHY(s) may be transparently transported via an Optical 155 Transport Network (OTN), as defined by ITU-T in [G.709] and 156 [G.798]. The OTN set of client mappings has been extended to 157 support the use cases identified in the OIF FlexE implementation 158 agreement. 160 This draft considers the variants in which the two peer FlexE devices 161 are both customer-edge devices, or when one is a customer-edge and 162 the other is provider edge devices. This list of use cases will help 163 identify the Control Plane (i.e. Routing and Signaling) extensions 164 that may be required. 166 1.1. Requirements Language 168 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 169 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 170 document are to be interpreted as described in RFC 2119 [RFC2119]. 172 2. Terminology 174 a. CE (Customer Edge) - the group of functions that support the 175 termination/origination of data received from or sent to the 176 network 178 b. Ethernet PHY: an entity representing Physical Coding Sublayer 179 (PCS), Physical Media Attachment (PMA), and Physical Media 180 Dependent (PMD) layers. 182 c. FlexE Calendar: The total capacity of a FlexE Group is 183 represented as a collection of slots which have a granularity of 184 5G. The calendar for a FlexE Group composed of n 100G PHYs is 185 represented as an array of 20n slots (each representing 5G of 186 bandwidth). This calendar is partitioned into sub-calendars, 187 with 20 slots per 100G PHY. Each FlexE client is mapped into one 188 or more calendar slots (based on the bandwidth the FlexE client 189 flow will need). 191 d. FlexE Client: An Ethernet flow based on a MAC data rate that may 192 or may not correspond to any Ethernet PHY rate. 194 e. FlexE Group: A FlexE Group is composed of from 1 to n Ethernet 195 PHYs. In the first version of FlexE each PHY is identified by a 196 number in the range {1-254}. 198 f. FlexE Shim: the layer that maps or demaps the FlexE client flows 199 carried over a FlexE Group. 201 g. LMP: Link Management Protocol 203 h. LSP: Label Switched Path 205 i. OTN: Optical Transport Network 207 j. SG15: ITU-T Study Group 15 (Transport, Access and Home). 209 k. TE: Traffic Engineering 211 l. TED: Traffic Engineering Database 213 3. FlexE Reference Model 215 The figure below gives a simplified FlexE reference model. 217 ................................... 218 n x PHY . n x crunched PHYs . 219 . . 220 +----+ . +-----+ +-----+ +-----+ . +----+ 221 | CE +--------------+ PE1 +----+ P +----+ PE2 +--------+ CE | 222 +----+ . +-----+ +-----+ +-----+ . +----+ 223 . . 224 +----+ m x PHY . . +----+ 225 | CE +---------------------------------------------------+ CE | 226 +----+ . . +----+ 227 . OTN Network . 228 . . 229 .................................... 231 +----+ p x PHY +----+ 232 | CE +---------------------------------------------------+ CE | 233 +----+ +----+ 235 Figure 1: FlexE Reference Model 237 The services offered by Flexible Ethernet are essentially the same as 238 for traditional Ethernet, connection less Ethernet transport. 239 However, when the relationship between the PHY and MAC layer are 240 setup by a GMPLS control plane there is a strong connection oriented 241 aspect. 243 4. Requirements 245 This section summarizes the control plane requirements for FlexE 246 Group and FlexE Client signaling and routing. 248 Req-1 The solution SHALL support the creation of a FlexE Group, 249 consisting of one or more (i.e., in the 1 to 254 range) 100GE 250 Ethernet PHY(s). 252 There are several alternatives that can meet this 253 requirement, e.g. routing and signaling protocols, or a 254 centralized controller/management system with network access 255 to the FlexE mux/demux at each FlexE Group termination point. 257 Req-2 The solution SHOULD be able to verify that the collection of 258 Ethernet PHY(s) included in a FlexE Group have the same 259 characteristics (e.g. number of PHYs, rate of PHYs, etc.) at 260 the peer FlexE shims. 262 Req-3 The solution SHALL support the ability to delete a FlexE 263 Group. 265 Req-4 The solution SHALL support the ability to administratively 266 lock/unlock a FlexE Group. 268 Req-5 It SHALL be possible to add/remove PHY(s) to/from an 269 operational FlexE group while the group has been 270 administratively locked. 272 Req-6 The solution SHALL support the ability to advertise and 273 discover information about FlexE capable nodes, and the FlexE 274 Groups and FlexE Clients they support. 276 Req-7 The system SHALL allow the addition (or removal) of one or 277 more FlexE clients on aFlexE Group. The addition (or 278 removal) of a FlexE client flow SHALL NOT affect the services 279 for the other FlexE client signals. 281 Req-8 The system SHALL allow the FlexE client signals to flexibly 282 span the set of Ethernet PHY(s) which comprise the FlexE 283 Group. 285 Req-9 The solution SHALL support FlexE client flow resizing without 286 affecting any existing FlexE clients within the same FlexE 287 Group. 289 Req-10 The solution SHALL support establishment of MPLS LSPs that 290 requires the support of a FlexE infrastructure. 292 5. GMPLS Controlled FlexE 294 The high level goals for using a GMPLS control plane for FlexE can be 295 summarized as: 297 o Set up a FlexE Group 299 o Set up a FlexE Client 301 o Advertise FlexE Groups and FlexE Clients 303 o Set up of a higher layer LSP that requires to be run over a FlexE 304 infrastructure. 306 5.1. Types of LSPs in a FlexE capable network 308 The FlexE infrastructure may be established in three different ways 310 o The FlexE Groups and FlexE Client may be pre-configured 312 o Only the FlexE groups may be pre-configured, while the setup of 313 the FlexE client is triggered by the request to setup a MPLS LSP 315 o The setup of both FlexE Group and FlexE Client may be triggered by 316 the request to setup an MPLS LSP. 318 5.2. Signaling Channel 320 In the type of equipment for which FlexE was first specified an out 321 of band signaling channel is not commonly available. If that is the 322 case, and the GMPLS FlexE control plane will be used, the FlexE Group 323 will have to setup by e.g. a management system and a FlexE Client on 324 that FlexE Group (also configured) will have to allocated as a 325 signaling channel. 327 Further details of the setup of the FlexE Groups, FlexE Clients and 328 MPLS LSPs over a FlexE infrastructure will be found in Section 7.2. 330 5.3. MPLS LSP in the FlexE Data Plane 332 FlexE is a true link layer technology, i.e. it is not switched, this 333 means that the FlexE Groups and FlexE Clients are terminated on the 334 next-hop node, and that the switching needs to take place on a higher 335 layer. 337 The FlexE technology can be used to establish link layer connectivity 338 with high and deterministic bandwidth. However, there is no way to, 339 in a deterministic way, allocate certain traffic to a specific FlexE 340 Client. A GMPLS control plane can do this. 342 A GMPLS controlled FlexE capable node may be thought of using the 343 traditional model of a node with a separation between control and 344 data plane. 346 +------------------+ 347 | +------------+ | 348 | | GMPLS | | 349 | | Control | | 350 | | Plane | | 351 | +------------+ | 352 | ^ | 353 | | | 354 | v | 355 | +------------+ | 356 | | FlexE | | 357 | | Data | | ^ 358 | | Plane | | 359 | +------------+ | 360 +------------------+ 362 Figure 2: GMPLS controlled FlexE Node 364 The GMPLS control plane will speak extended standard GMPLS protocols 365 with its neighbours and peers. 367 Node A Node B Node Z 368 +--CP 369 +-|-----------+ |------------------+ ~ +---------+ 370 | | | | | | | 371 | | +------+ | | +--------------+ | | +-----+ | 372 LSP | +->| v | | | | ....x..... | | | | ^ | | 373 | | | . | | | | . . | | | | . | | 374 | | +--.---+ | | +--.--------.--+ | | +--.--+ | 375 FlexE | +->| o | | | | o | | o | | | | o | | 376 Client | | | o | | | | o | | o | | | | o | | 377 | | +--o---| | | +--o--+ +--o--+ | | +--o--| | 378 FlexE | +->| U | | | | U | | U | | | | U | | 379 Group | | U | | | | U | | U | | | | U | | 380 | +--U---| | | +--U--+ +--U--+ | | +--U--+ | 381 |-------U-----+ +----U--------U----+ +----U----+ 382 U U U U 383 UUUUUUUUUUUUUUUUUUUUU UUUUUUU ~ UUUUUUUU 385 Legend ... = LSP 386 ooo = FlexE Client 387 UUU = FlexE Group 389 Figure 3: GMPLS controlled network with FlexE infrastructure 391 Figure 3 describes how an MPLS LSP is mapped over a FlexE Client and 392 FlexE Group. 394 5.4. Configuring the data plane in FlexE capable nodes 396 In Figure 3 we show an LSP, a FlexE Client and a FlexE Group, the LSP 397 is there because while the FlexE Channel and Group are not switched, 398 switching in our example takes place on the LSP level. This section 399 will discuss establishment of FlexE Clients and Groups, and mapping 400 of the LSP onto a FlexE Client. 402 The establishment of a LSP over a FlexE system is very similar to how 403 this is done in any other system. Building on information gathered 404 through the routing system and using the GMPLS signaling to establish 405 the LSP. 407 5.4.1. Configure/Establish a FlexE Group/Link 409 Consider the setup of a FlexE Group between node A and B, 410 corresponding to the row of U's from node A to B in Figure 3. The 411 FlexE group is considered to consist of n PHYs, but does not have any 412 FlexE Clients defined from start. 414 When this is done by the GMPLS control plane, two conditions need to 415 be fulfilled (1) there need to be a data channel defined between node 416 A and B; and (2) a FlexE capable IGP-TE protocol needs to be running 417 in the network. 419 Node A will send an RSVP-TE message to node be with the information 420 describing the FlexE Group to be setup. This information might be 421 thought of as the "FlexE Group Label" (or part of the FlexE label). 422 It will contain at least the following information: 424 o A FlexE Group Identifier (FGid). 426 o The number of active FlexE Channels (numFC), where 0 indicates 427 that zero clients are active. 429 o Number of PHYs that the FlexE Group is composed of, for each PHY 431 * PHY identifier 433 * PHY bandwidth 435 * slot granularity/number of slots 437 * available and unavailable slots 439 When node B receives the RSVP-TE message it checks that it can setup 440 the requested FlexE Group. If the check turns positive, node send an 441 acknowledgment to node A and the FlexE Group is setup. 443 A more detailed description of how to setup a FlexE Group, will be 444 included in the draft dealing with signaling in detail. 446 5.4.2. Configure/Establish a FlexE Client 448 Consider the situation where a FlexE Group is already established (as 449 described in Section 5.4.1) and an m G FlexE Client is needed. 450 Similar to the establishment of the FlexE Group, node A will send a 451 RSV-TE message to node B. 453 This RSVP-TE message include at least the following information: 455 o FlexE Group Identifier 457 o FlexE Client Identifier 459 o from which PHYs the slots will allocated, i.e. slots might come 460 from more than one PHY. 462 o Information per PHY 464 * PHY bandwidth 466 * slot granularity 468 * available/unavailable slots 470 * allocated slots 472 A more detailed description of how to setup a FlexE Channel, will be 473 included in the draft dealing with signaling in detail. 475 5.4.3. Advertise FlexE Groups and FlexE lts 477 Once the FlexE Group and FlexE CLielts are configured they can be 478 advertised into the routing system as normal routing adjacencies, 479 including the FlexE specific TE information. 481 6. Framework and Architecture 483 This section discusses FlexE framework and architecture. Framework 484 is taken to mean how FlexE interoperates with other parts of the data 485 communication system. Architecture is taken to mean how functional 486 groups and elements within FlexE work together to deliver the 487 expected FlexE services. Framework is taken to mean how FlexE 488 interacts with it environment. 490 6.1. FlexE Framework 492 The service offered by Flexible Ethernet is a transport service very 493 similar (or even identical) to the service offered by Ethernet. 495 There are two major additions supported by FlexE: 497 o FlexE is intended to support high bandwidth and FlexE can offer 498 granular bandwidth from 5Gbits/s and a bandwidth as high as the 499 FlexE Group allows. 501 o As FlexE groups and clients are setup as a configuration activity, 502 by a centralized controller or by a GMPLS control plane the 503 service is connection oriented. 505 6.2. FlexE Architecture 507 6.2.1. Architecture Components 509 This section discusses the different parts of FlexE signaling and 510 routing and how these parts interoperate. 512 The FlexE routing mechanism is used to provide resource available 513 information for setup of higher layer LSPs, like Ethernet PHYs' 514 information, partial-rate support information. Based on the resource 515 available information advertised by routing protocol, an end-to-end 516 FlexE connection is computed, and then the signaling protocol is used 517 to set up the end-to-end connection. 519 FlexE signaling mechanism is used to setup LSPs. 521 MPLS forwarding over a FlexE infrastructure is different from 522 forwarding over other infrastructures. When MPLS runs over a FlexE 523 infrastructure it is possible that there are more than FlexE Client 524 that meet the next-hop requirements, often it is possible to use any 525 suitable FlexE Clientfor a hop between two nodes. If the mapping 526 between a MPLS encapsulated packet and the FlexE Client, this mapping 527 need to be explicit when the LSP is set up, and the MPLS label will 528 be used to find the correct FlexE Client. 530 6.2.2. FlexE Layer Model 532 The FLexE layer model is similar Ethernet model, the Ethernet PHY 533 layer corresponds to the "FlexE Group", and the MAC layer corresponds 534 to the "FlexE Client". 536 As different from earlier Ethernet the combination of Flexe Group and 537 Client allows for a huge freedom when it comes to define the 538 bandwidth of an Ethernet connectivity. 540 6.2.2.1. FlexE Group structure 542 The FlexE Group might be supported by virtually any transport 543 network, including the Ethernet PHY. While the Ethernet PHY offers a 544 fixed bandwidth the FlexE Group has been structured into 5 Gbit/s 545 slots. This means that the FlexE Group can support FlexE clients of 546 a variety of bandwidths. 548 The first version is defined for 20 slots of 5 Git/s over a 100 Gbit/ 549 s PHY. The 100 Gbit/s PHYs can be bonded to give higher bandwidth. 551 6.2.2.2. FlexE Client mapping 553 A FlexE client is an Ethernet flow based on a MAC data rate that may 554 or may not correspond to any Ethernet PHY rate. The FlexE Shim is 555 the layer that maps or demaps the FlexE client flows carried over a 556 FlexE group. As defined in [OIFFLEXE1], MAC rates of 10, 40, and any 557 multiple of 25 Gbit/s are supported. This means that if there is a 558 100 Gbit/s FlexE Group between A and B, a FlexE client of 10, 25, 40, 559 50, 75 and 100 Gbit/s can be created. 561 However, by bonding, for example 5 PHYs of 100 Git/s to a single 562 FlexE group, FlexE clients of 500 Gbit/s can be supported. 564 7. Control Plane 566 This section discusses the procedures and extensions needed to the 567 GMPLS Control Plane to establish FlexE LSPs. 569 There are several ways to establish FlexE groups, allocate slots for 570 FlexE clients, and setup higher layer LSPs. A configuration tool, a 571 centralized controller or the GMPLS control plane can all be used. 573 To create the FlexE GMPLS control plane Groups, FlexE Clients and 574 higher layer LSPs, extensions to the following protocols may be 575 needed: 577 o "RSVP-TE: Extensions to RSVP for LSP Tunnels" (RSVP-TE) [RFC3209] 579 o "Link Management Protocol" (LMP) [RFC4204] 581 o "Path Computation Element (PCE) Communication Protocol" (PCEP) 582 [RFC5440] 584 o IS-IS Extensions for Traffic Engineering (ISIS-TE) [RFC5305] 586 o "OSPF Extensions in Support of Generalized Multi-Protocol Label 587 Switching (GMPLS)" (OSPF-TE) [RFC4203] 589 o "North-Bound Distribution of Link-State and Traffic Engineering 590 (TE) Information Using BGP" (BGP-LS) [RFC7752] 592 A FlexE control plane YANG model will also be needed. 594 Section 7.2 and Section 7.1 discusses the role of the GMPLS control 595 plane when primarily setting up LSPs. 597 When discussing the signaling and routing procedures we assume that 598 the FlexE group has been established prior to executing the 599 procedures needed to establish an LSP. Technically it is possible to 600 establish FlexE group, allocate FlexE client slots and LSP with a 601 single exchange of GMPLS signaling messages. 603 7.1. GMPLS Routing 605 To establish an LSP the Traffic Engineering (TE) information is the 606 most critical information, e.g. resource utilization on interfaces 607 and link, including the availability of slots on the FlexE groups. 608 The GPMPLS routing protocols needs to be extended to handle this 609 information. The Traffic Engineering Database (TED) will keep an 610 updated version of this information. 612 The FlexE capable nodes will be identified by IP-addresses, and the 613 routing and traffic engineering information will be flooded to all 614 nodes within the routing domain using TCP/IP. 616 When an LSP over the FlexE infrastructure is about to be setup, e.g. 617 R1 - R4 - R5 in Figure 4 the information in the TED is used verify 618 that resources are available. When it is conformed that the LSP is 619 established the TED is updated, marking the resources used for the 620 new LSP as used. Similarly when a LSP is taken down the resources 621 are marked as free. 623 7.2. GMPLS Signaling 625 As described in Section 5 the state of the FlexE infrastructure may 626 effect the actions needed to setup an LSPin a FlexE capable network. 627 The FlexE infrastructure maybe be: 629 1. fully pre-configured 630 2. partially pre-configured, i.e. the FlexE Group may be pre- 631 configured, but not the FlexE Clients 633 3. not pre-configured, i.e. the setup of FlexE Group and FlexE 634 Client will be triggered because of the request to setup an LSP. 636 Figure 4 will be used to illustrate the different cases. 638 +----+ 639 | R1 +---------------------+ 640 +----+ | 641 | 642 +----+ +--+--+ +----+ 643 | R2 +------------------+ R4 +-------------------------+ R5 | 644 +----+ +--+--+ +----+ 645 | 646 +----+ | 647 | R3 +---------------------+ PHY R1 to R4 100 Gbit(s 648 +----+ PHY R2 to R4 100 Gbit(s 649 PHY R3 to R4 100 Gbit(s 650 PHY R4 to R5 200 Gbit(s 652 Figure 4: FlexE LSP Example 654 The text in Section 7.2 is not a specification of the GMPLS signaling 655 extensions for FlexE capable network, it is a description to 656 illustrate the expected features of such a protocol. Nor do we 657 discuss failure scenarios. 659 7.2.1. LSP setu with pre-configured FlexE infrastructure 661 In this first example, referencing Figure 4, one 100 Gbit/s FlexE 662 group is configured between R1 and R4, between R2 and R4, and between 663 R3 and R4. Between R4 and R5 there is a 200 Gbit/s FlexE Group. 665 Over each 100 Gbit/s FlexE Group there are four 5 Gbit/s, two 20 666 Gbit/s and one 40 Gbit/s FlrxE Clients configured. Over the 200 Git/ 667 s FlexE Group there are eoght 5 Gbit/s, four 20 Gbit/s and tow 40 668 Gbit/s FlrxE Clients configured. 670 One of the 5 Gbit/s FlexE Clients on each FlexE Groups are used as 671 signaling channel. 673 To establish the for example a 200 Mbit/s MPLS LSP the normal GMPLS 674 request/response procedures are followed. R1 sends the request to 675 R4, R4 allocate resources on one of the FlexE Ckients, forward the 676 request to R5. R5 responds to R4 indicating the label and the FlexE 677 Client the traffic should be sent over, R4 does the same for R1. 679 The only difference between the standard signaling and what happens 680 here is that there the assigned label will be used to find the right 681 FlexE Client. 683 7.2.2. LSP setup with partially configured FlexE infrastructure 685 In the second example, also referencing Figure 4, the FlexE Groups 686 are set up in the same way as in the first example, however only one 687 5 Gbit/s FlexE Client per FlexE Group are established by 688 configuration. This FlexE Client will be used for signaling. 690 When preparing to send the request that a 5 Gbit/s MPLS LSP shall be 691 set up R1 discovers that there are no feasible FlexE Client between 692 R1 aand R4. R1 therefore sends the request to establish such a FlexE 693 Client, when receiving the request R4 allocates resources for the 694 FlexE Client on the FlexE Group. There may be different strategies 695 for allocating the bandwidth for this FlexE client. Such strategies 696 are out of scope for this document. R1 then sends the information 697 about the FlexE Client to R1, and both ends establish the FlexE 698 Client. 700 When the FlexE Client between R1 and R4 is established, R1 proceeds 701 to send the request for an MPLS LSP to R4. R4 will discover that a 702 feasible FlexE Client is missing between R4 and R5. The same 703 procedure s for setting up the FlexE Client between R1 and R4 is 704 repeated for R4 and R5. When there is a feasible FlexE Client 705 available the signaling to set up the MPLS LSP continues as normal. 707 The label allocated for the MPLS LSP will be used to find the correct 708 FlexE Client. 710 When a FlexE Clients is set up in this way they can be announced into 711 the routing system in two different ways. First, they can be made 712 generally available, i.e. it will be free to use for anyone that want 713 to set up LSPs over the FlexE Group between R1 and R4 and between R4 714 and R5. Second, the use of the FlexE Clients may be restricted to 715 the application that initially did set up the FlexE Client. 717 7.2.3. LSP setup with non-configured FlexE infrastructure 719 This example also refers to Figure 4 as different from the earlier 720 example no FlexE Group or FlexE Client configuration is done prior to 721 the first request for an MPLS LSP over the FlexE infrastructure. 723 To make the set up of LSPs in a FlexE network where no FlexE Groups 724 or FlexE Clients have been configured two conditions need to be 725 fulfilled. First an out of band signaling channel must be available. 726 Second the FlexE Capabilities must be announced in to the IGP and/or 727 centralized controller. 729 If these two conditions are fulfilled, the set up of an MPLS LSP 730 progress pretty much as in the partially configured network. The 731 difference is that the set up of both the FlexE Group and FlexE 732 Client are triggered by the request to set up an MPLS LSP. 734 As in the partially configured case FlexE Clients can be announced 735 into the routing system in two different modes, either they are 736 generally availble. It or they are reserved for the applications 737 that first established them. 739 7.2.4. Packet Label Switching Data Plane 741 This section discusses how the FlexE LSP data plane works. In 742 general it can be said that the interface offered by the FlexE Shim 743 and the FlexE client is equivalent to the interface offered by the 744 Ethernet MAC. 746 Figure 5 below illustrates the FlexE packet switching data plane 747 procedures. 749 R1 R3 R4 750 ............. ...................... ........... 751 . +-------+ . . +----------------+ . . +-----+ . 752 . | LSP | . . | LSP \ / LSP | . . | LSP | . 753 . | a | . . | a \/ b | . . | b | . 754 . +-------+ . . +----------------+ . . +-----+ . 755 . | ETH | . . | ETH | | ETH | . . | ETH | . 756 . | i/f | . . | i/f | | i/f | . . | i/f | . 757 . +-------+ . . +-----+ +-----+ . . +-----+ . 758 . | FlexE | . . |FlexE| |FlexE| . . |FlexE| . 759 . | trsp | . . |trsp | |trsp | . . |trsp | . 760 . +---+---+ . . +--+--+ +--+--+ . . +--+--+ . 761 ......|...... .....^..........|..... .....^..... 762 | | | | 763 +--------------------+ +--------------------+ 765 Figure 5: LSP over FlexE Data Plane 767 The data plane processes packets like this: 769 o The LSP encapsulating and forawrding function in node R1 receives 770 a packet that needs to be encapsulated as an MPLS packet with the 771 label "a". The label "a" is used to figure out which FlexE 772 emulated Ethernet interfaces the label encapsulated packet need to 773 be forwarded over. 775 o The Ethernet interfaces, by means of FlexE transport, forwards the 776 packet to node R3. Node R3 swaps the label "a" to label "b" and 777 uses "b" to decide over which interface to send the packet. 779 o Node R3 forwards the packet to node R, which terminates the LSP. 781 Sending MPLS encapsulated packets over a FlexE Client is similar to 782 send them over an Ethernet 802.1 interface. The critical differences 783 are: 785 o FlexE channelized sub-interfaces guarantee a deterministic 786 bandwidth for an LSP. 788 o When a application that originally establish a FlexE Client 789 reserve it for use by that application only, it is possible to 790 create uninfringeable bandwidth end-to-end for an MPLS LSP. 792 o FlexE infrastructure allows for creating very large end to end 793 bandwidth 795 8. Operations, Administration, and Maintenance (OAM) 797 To be added in a later version. 799 9. Acknowledgements 801 10. IANA Considerations 803 This memo includes no request to IANA. 805 Note to the RFC Editor: This section should be removed before 806 publishing. 808 11. Security Considerations 810 To be added in a later version. 812 12. Contributors 814 Khuzema Pithewan, Infinera Corp, kpithewan@infinera.com 816 Fatai Zhang, Huawei, zhangfatai@huawei.com 818 Jie Dong, Huawei, jie.dong@huawei.com 820 Zongpeng Du, Huawei, duzongpeng@huawei.com 822 Xian Zhang, Huawei, zhang.xian@huawei.com 824 James Huang, Huawei, james.huang@huawei.com 826 Qiwen Zhong, Huawei, zhongqiwen@huawei.com 828 Yongqing Zhu China Telecom zhuyq@gsta.com 830 Huanan Chen China Telecom chenhuanan@gsta.com 832 13. References 834 13.1. Normative References 836 [G.709] ITU, "Optical Transport Network Interfaces 837 (http://www.itu.int/rec/T-REC-G.709-201606-P/en)", July 838 2016. 840 [G.798] ITU, "Characteristics of optical transport network 841 hierarchy equipment functional blocks 842 (http://www.itu.int/rec/T-REC-G.798-201212-I/en)", 843 February 2014. 845 [G.8021] ITU, "Characteristics of Ethernet transport network 846 equipment functional blocks", November 2016. 848 [G.872] ITU, "Architecture of optical transport networks", January 849 2017. 851 [OIFFLEXE1] 852 OIF, "FLex Ethernet Implementation Agreement Version 1.0 853 (OIF-FLEXE-01.0)", March 2016. 855 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 856 Requirement Levels", BCP 14, RFC 2119, 857 DOI 10.17487/RFC2119, March 1997, 858 . 860 13.2. Informative References 862 [RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., 863 and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP 864 Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001, 865 . 867 [RFC4203] Kompella, K., Ed. and Y. Rekhter, Ed., "OSPF Extensions in 868 Support of Generalized Multi-Protocol Label Switching 869 (GMPLS)", RFC 4203, DOI 10.17487/RFC4203, October 2005, 870 . 872 [RFC4204] Lang, J., Ed., "Link Management Protocol (LMP)", RFC 4204, 873 DOI 10.17487/RFC4204, October 2005, 874 . 876 [RFC5305] Li, T. and H. Smit, "IS-IS Extensions for Traffic 877 Engineering", RFC 5305, DOI 10.17487/RFC5305, October 878 2008, . 880 [RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation 881 Element (PCE) Communication Protocol (PCEP)", RFC 5440, 882 DOI 10.17487/RFC5440, March 2009, 883 . 885 [RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and 886 S. Ray, "North-Bound Distribution of Link-State and 887 Traffic Engineering (TE) Information Using BGP", RFC 7752, 888 DOI 10.17487/RFC7752, March 2016, 889 . 891 Authors' Addresses 893 Iftekhar Hussain 894 Infinera Corp 895 169 Java Drive 896 Sunnyvale, CA 94089 897 USA 899 Email: IHussain@infinera.com 901 Radha Valiveti 902 Infinera Corp 903 169 Java Drive 904 Sunnyvale, CA 94089 905 USA 907 Email: rvaliveti@infinera.com 909 Qilei Wang 910 ZTE 911 Nanjing 912 CN 914 Email: wang.qilei@zte.com.cn 916 Loa Andersson 917 Huawei 918 Stockholm 919 Sweden 921 Email: loa@pi.nu 923 Mach Chen 924 Huawei 925 CN 927 Email: mach.chen@huawei.com 928 Haomian Zheng 929 Huawei 930 CN 932 Email: zhenghaomian@huawei.com