idnits 2.17.1 draft-geng-detnet-dp-sol-srv6-01.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 04, 2019) is 1750 days in the past. Is this intentional? Checking references for intended status: Experimental ---------------------------------------------------------------------------- == Missing Reference: 'SL' is mentioned on line 490, but not defined -- Looks like a reference, but probably isn't: '2' on line 155 -- Looks like a reference, but probably isn't: '1' on line 155 -- Looks like a reference, but probably isn't: '0' on line 595 == Unused Reference: 'I-D.ietf-detnet-dp-sol-mpls' is defined on line 653, but no explicit reference was found in the text == Outdated reference: A later version (-26) exists of draft-ietf-6man-segment-routing-header-21 == Outdated reference: A later version (-22) exists of draft-ietf-spring-segment-routing-policy-03 Summary: 0 errors (**), 0 flaws (~~), 5 warnings (==), 4 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group X. Geng 3 Internet-Draft M. Chen 4 Intended status: Experimental Huawei 5 Expires: January 5, 2020 Y. Zhu 6 China Telecom 7 July 04, 2019 9 DetNet SRv6 Data Plane Encapsulation 10 draft-geng-detnet-dp-sol-srv6-01 12 Abstract 14 This document specifies Deterministic Networking data plane operation 15 for SRv6 encapsulated user data. 17 Requirements Language 19 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 20 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 21 document are to be interpreted as described in RFC 2119 [RFC2119]. 23 Status of This Memo 25 This Internet-Draft is submitted in full conformance with the 26 provisions of BCP 78 and BCP 79. 28 Internet-Drafts are working documents of the Internet Engineering 29 Task Force (IETF). Note that other groups may also distribute 30 working documents as Internet-Drafts. The list of current Internet- 31 Drafts is at https://datatracker.ietf.org/drafts/current/. 33 Internet-Drafts are draft documents valid for a maximum of six months 34 and may be updated, replaced, or obsoleted by other documents at any 35 time. It is inappropriate to use Internet-Drafts as reference 36 material or to cite them other than as "work in progress." 38 This Internet-Draft will expire on January 5, 2020. 40 Copyright Notice 42 Copyright (c) 2019 IETF Trust and the persons identified as the 43 document authors. All rights reserved. 45 This document is subject to BCP 78 and the IETF Trust's Legal 46 Provisions Relating to IETF Documents 47 (https://trustee.ietf.org/license-info) in effect on the date of 48 publication of this document. Please review these documents 49 carefully, as they describe your rights and restrictions with respect 50 to this document. Code Components extracted from this document must 51 include Simplified BSD License text as described in Section 4.e of 52 the Trust Legal Provisions and are provided without warranty as 53 described in the Simplified BSD License. 55 Table of Contents 57 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 58 2. Terminology and Conventions . . . . . . . . . . . . . . . . . 3 59 2.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 60 2.2. Conventions . . . . . . . . . . . . . . . . . . . . . . . 4 61 3. SRv6 DetNet Data Plane Overview . . . . . . . . . . . . . . . 4 62 3.1. SRv6 DetNet Data Plane Layers . . . . . . . . . . . . . . 5 63 3.2. SRv6 DetNet Data Plane Scenarios . . . . . . . . . . . . 5 64 4. SRv6 DetNet Data Plane Solution Considerations . . . . . . . 7 65 5. SRv6 DetNet Data Plane Solution for Service Sub-layer . . . . 8 66 5.1. TLV Based SRv6 Data Plane Solution . . . . . . . . . . . 8 67 5.1.1. Encapsulation . . . . . . . . . . . . . . . . . . . . 8 68 5.1.2. SRv6 Network Programming new Functions . . . . . . . 10 69 5.2. SID Based SRv6 Data Plane Solution . . . . . . . . . . . 11 70 5.2.1. Encapsulation . . . . . . . . . . . . . . . . . . . . 11 71 5.2.2. Functions . . . . . . . . . . . . . . . . . . . . . . 12 72 5.3. DetNet SID Based SRv6 Data Plane Solution . . . . . . . . 13 73 5.3.1. Encapulation . . . . . . . . . . . . . . . . . . . . 13 74 5.3.2. Functions . . . . . . . . . . . . . . . . . . . . . . 14 75 6. SRv6 DetNet Data Plane Solution for Transport Sub-layer . . . 14 76 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14 77 8. Security Considerations . . . . . . . . . . . . . . . . . . . 14 78 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14 79 10. Normative References . . . . . . . . . . . . . . . . . . . . 14 80 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15 82 1. Introduction 84 Deterministic Networking (DetNet), as described in 85 [I-D.ietf-detnet-architecture] provides a capability to carry 86 specified data flows with extremely low data loss rates and bounded 87 latency within a network domain. DetNet is enabled by a group of 88 technologies, such as resource allocation, service protection and 89 explicit routes. 91 Segment Routing(SR) leverages the source routing paradigm. An 92 ingress node steers a packet through an ordered list of instructions, 93 called "segments". SR can be applied over IPv6 data plane using the 94 Segment Routing Extension Header 95 (SRH,[I-D.ietf-6man-segment-routing-header]). A segment in segment 96 routing terminology is not limited to a routing/forwarding function. 98 A segment can be associated to an arbitrary processing of the packet 99 in the node identified by the segment. In other words, an SRv6 100 Segment can indicate functions that are executed locally in the node 101 where they are defined. SRv6 network Programming 102 [I-D.filsfils-spring-srv6-network-programming] describe the different 103 segments and functions associated to them. 105 This document describes how to implement DetNet in an SRv6 enabled 106 domain, including : 108 o Source routing, which steers the DetNet flows through the network 109 according to an explicit path with allocated resources; 111 o Network programming, which applies instructions (functions) to 112 packets in some special nodes (or even all the nodes) along the path 113 in order to guarantee, e.g., service protection and congestion 114 protection. 116 DetNet SRv6 encapsulation and new SRv6 functions 117 ([I-D.filsfils-spring-srv6-network-programming]) for DetNet are 118 defined in this document. Control plane and OAM are not in the scope 119 of this document. 121 Control plane and OAM are not in the scope of this document. 123 2. Terminology and Conventions 125 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 126 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 127 document are to be interpreted as described in [RFC2119]. 129 2.1. Terminology 131 Terminologies for DetNet go along with the definition in 132 [I-D.ietf-detnet-architecture] and [RFC8402]. Other terminologies 133 are defined as follows: 135 o NH: The IPv6 next-header field. 137 o SID: A Segment Identifier ([RFC8402]). 139 o SRH: The Segment Routing Header 140 ([I-D.ietf-6man-segment-routing-header]). 142 2.2. Conventions 144 Conventions in the document are defined as follows: 146 o NH=SRH means that NH is 43 with routing type 4 which is (as 147 defined in [I-D.ietf-6man-segment-routing-header], the values 148 representing the SRH. 150 o A SID list is represented as where S1 is the first 151 SID to visit, S2 is the second SID to visit and S3 is the last SID 152 to visit along the SR path. 154 o SRH[SL] represents the SID pointed by the SL field in the first 155 SRH. In our example, SRH[2] represents S1, SRH[1] represents S2 156 and SRH[0] represents S3. It has to be noted 157 that[I-D.ietf-6man-segment-routing-header] defines the segment 158 list encoding in the reverse order of the path. A path 159 represented by , will be encoded in the SRH as follows: 161 SegmentList[0]=S3 163 SegmentList[1]=S2 165 SegmentList[2]=S1 167 The reverse encoding has been defined in order to optimise the 168 processing time of the segment list. See [draft-ietf-6man- 169 segment-routing-header] for more details. 171 o (SA,DA) (S3, S2, S1; SL) represents an IPv6 packet with: 173 IPv6 header with source and destination addresses SA and DA 174 respectively, and next-header set to SRH (i.e.: 43 with type 4) 175 , with a list of segments(SIDs) with SegmentsLeft 176 = SL 178 The payload of the packet is not represented 180 (S3, S2, S1; SL) represents the same SID list as , 181 but encoded in the SRH format where the rightmost SID in the 182 SRH is the first SID and the leftmost SID in the SRH is the 183 last SID 185 3. SRv6 DetNet Data Plane Overview 186 3.1. SRv6 DetNet Data Plane Layers 188 [I-D.ietf-detnet-architecture]decomposes the DetNet data plane into 189 two sub-layers: service sub-layer and transport sub-layer. Different 190 from DetNet MPLS data plane solution, which uses DetNet Control 191 Word(d-CW) and S-Label to support service sub-layer and uses T-Label 192 to support transport sub-layer, no explicit sub-layer division exists 193 in SRv6 data plane. A classical SRv6 DetNet data plane solution is 194 showed in the picture below: 196 +-------------------+ 197 | Outer Ipv6 Header | 198 +-------------------+ 199 | SRH | 200 +-------------------+ +-------------------+ 201 | Ipv6 Header | ----> | Ipv6 Header | 202 +-------------------+ +-------------------+ 204 The outer IPv6 Header with the SRH is used for carrying DetNet flows. 205 Traffic Engineering is instantiated in the segment list of SRH, and 206 other functions and arguments for service protection (packet 207 replication, elimination and ordering) and congestion control (packet 208 queuing and forwarding) are also defined in the SRH. 210 3.2. SRv6 DetNet Data Plane Scenarios 212 | | 213 ----IPv6--->|<---------------SRv6 DetNet------------->|<----IPv6--- 214 | | 215 | +------+T2+----+ | 216 +---+ +---+ +-+-+ +-+-+ +---+ +---+ 217 | E1+----| In|--+T1+--+R1 | |R2 |--+T4+--| Eg+----+ E2| 218 +---+ +---+ +-+-+ +-+-+ +---+ +---+ 219 +-----+T3+-----+ 221 The figure above shows that an IPv6 flow is sent out from the end 222 station E1. The packet of the flow is encapsulated in an outer 223 IPv6+SRH header as a DetNet SRv6 packet in the Ingress(In) and 224 transported through an SRv6 DetNet domain. In the Egress(Eg), the 225 outer IPv6 header+SRH of the packet is popped, and the packet is sent 226 to the destination E2. 228 The figure above shows that an IPv6 flow is sent our from the end 229 station: E1. The packet of the flow is encapsulated as a DetNet SRv6 230 packet in the Ingress(In) and transported through an SRv6 DetNet 231 domain. In the Egress(Eg), the upper IPv6 header with SRH of the 232 packet is popped, and the packet is transmitted to the 233 destination(E2). 235 The DetNet packet processing is as follows: 237 Ingress: 239 Inserts the SRv6 Policy that will steer the packet from Ingress to 240 the destination 242 The methods and mechanisms used for defining, instantiating and 243 applying the policy are outside of this document. An example of 244 policies are described in [I-D.ietf-spring-segment-routing-policy] 246 Flow Identification and Sequence Number are carried in the SRH. 248 Relay Node 1(Replication Node): 250 Replicates the payload and IPv6 Header with the SRH. This is a 251 new function in the context of SRv6 Network Programming which will 252 associate a given SID to a replication instruction in the node 253 originating and advertising the SID. The replication instruction 254 includes: 256 * The removal of the existing IPv6+SRH header 258 * The encapsulation into a new outer IPv6+SRH header. Each 259 packet (the original and the duplicated) are encapsulated into 260 respectively new outer IPv6+SRH headers. 262 Binding two different SRv6 Policies respectively to the original 263 packet and the replicated packet, which can steer the packets from 264 Relay Node 1 to Relay Node 2 through two tunnels. 266 Relay Node 2(Elimination Node): 268 Eliminates the redundant packets. 270 Binds a new SRv6 Policy to the survival packet, which steers the 271 packet from Relay Node 2 to Egress. 273 Egress: 275 Decapsulates the outer Ipv6 header. 277 Sends the inter packet to the End Station 2. 279 The DetNet packet encapsulation is illustrated here below. It has to 280 be noted that, in the example below, the R2 address is a SRH SID 281 associated to a TBD function related to the packet replication the 282 node R1 has to perform. The same (or reverse) apply to node R2 which 283 is in charge of the discard of the duplicated packet. Here also a 284 new function will have a new SID allocated to it and representing the 285 delete of the duplication in R2. 287 End Station1 output packet: (E1,E2) 289 Ingress output packet: (In, T1)(R1,T1, SL=2)(E1,E2) 291 Transit Node1 output packet: (In, R1)(R1,T1,SL=1)(E1,E2) 293 Relay Node1 output packets : (R1,T2)(R2,T2,SL=2)(E1,E2), 294 (R1,T3)(R2,T3,SL=2)(E1,E2) 296 Transit Node2 output packet: (R1, R2)(R2,T2,SL=1)(E1,E2) 298 Transit Node3 output packet: (R1, R2)(R2,T3,SL=1)(E1,E2) 300 Relay Node2 output packet: (R2, T4)(Eg,T4,SL=2)(E1,E2) 302 Transit Node4 output packet: (R2, Eg)(Eg,T4,SL=1)(E1,E2) 304 Egress out : (E1,E2) 306 4. SRv6 DetNet Data Plane Solution Considerations 308 To carry DetNet over SRv6, the following elements are required: 310 1. A method of identifying the SRv6 payload type; 312 2. A suitable explicit path to deliver the DetNet flow ; 314 3. A method of indicating packet processing, such as PREOF(Packet 315 Replication, Elimination and Ordering as defined in 316 [I-D.ietf-detnet-architecture]); 318 4. A method of identifying the DetNet flow; 320 5. A method of carrying DetNet sequence number; 322 6. A method of carrying queuing and forwarding indication to do 323 congestion protection; 325 In this design, DetNet flows are encapsulated in an outer IPv6+SRH 326 header at the Ingress Node. The SR policy identified in the SRH 327 steers the DetNet flow along a selected path. The explicit path 328 followed by a DetNet flow, which protect it from temporary 329 interruptions caused by the convergence of routing, is encoded within 330 the SID list of the SR policy. The network device inside the DetNet 331 domain forwards the packet according to IPv6 Destination Address(DA), 332 and the IPv6 DA is updated with the SID List according to SRv6 333 forwarding procedures defined in 334 [I-D.ietf-6man-segment-routing-header] and 335 [I-D.filsfils-spring-srv6-network-programming] 337 With SRv6 network programming, the SID list can also give instruments 338 representing a function to be called at the node in the DetNet 339 domain. Therefore DetNet specific functions defined in 340 [I-D.ietf-detnet-architecture], corresponding to local packet 341 processing in the network, can also be implemented by SRv6. New 342 functions associated with SIDs for DetNet are defined in this 343 document. 345 This document describes how DetNet flows are encapsulated/identified, 346 and how functions of Packet Replication/Elimination/Ordering are 347 implemented in an SRv6 domain. Congestion protection is also in the 348 scope of this document. 350 Editor: This version only covers the functions of service protection 351 and the congestion protection considerations will be added in the 352 following versions. 354 5. SRv6 DetNet Data Plane Solution for Service Sub-layer 356 This section defines options of SRv6 data plane solution to support 357 DetNet Service Sub-layer. 359 5.1. TLV Based SRv6 Data Plane Solution 361 5.1.1. Encapsulation 363 An SRv6 Segment is a 128-bit value. SID is used as a shorter 364 reference for "SRv6 Segment Identifier" or "SRV6 Segment". SRv6 SID 365 can also be represented as LOC:FUNCT, where: 367 LOC, means "LOCATION" and defines the node associated with the SID 368 (i.e.: represented by the SID). 370 FUNCT, means "FUNCTION", and identifies the processing that the 371 node specified in LOC applies to the packet. See 372 [I-D.filsfils-spring-srv6-network-programming] for details on SRV6 373 Network Programming. 375 The SRH for DetNet in the outer IPv6 header is showed as follows, 376 according to [I-D.ietf-6man-segment-routing-header] and 377 [I-D.filsfils-spring-srv6-network-programming]: 379 0 1 2 3 380 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 1 381 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 382 | Next Header | Hdr Ext Len | Routing Type | Segment Left | 383 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 384 | Last Entry | Flags | Tag | 385 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 386 | | 387 | Location & Function | 388 | (Segment List[0] for relay node or edge node) | 389 | | 390 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 391 | ... | 392 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 393 | | 394 | Segment List[n] | 395 | | 396 | | 397 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 398 | Optional TLVs | 399 | ... | 400 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 402 The SRH specification allows the use of optional TLVs. Two new TLVs 403 are defined to support DetNet service protection. DetNet Flow 404 Identification TLV is used to uniquely identify a DetNet flow in an 405 SRv6 DetNet node. DetNet sequence number is used to discriminate 406 packets in the same DetNet flow. They are defined as follows: 408 0 1 2 3 409 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 1 410 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 411 | Type | Length | RESERVED | 412 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 413 | RESERVED | Flow Identification | 414 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 416 where: 418 o Type: 8bits, to be assigned by IANA. 420 o Length: 8 octets. 422 o RESERVED: 28 bits, MUST be 0 on transmission and ignored on 423 receipt. 425 o Flow Identification: 20 bits, which is used for identifying DetNet 426 flow. 428 0 1 2 3 429 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 1 430 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 431 | Type | Length | RESERVED | 432 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 433 |RESERVD| Sequence Number | 434 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 436 where: 438 o Type: 8 bits, to be assigned by IANA. 440 o Length: 8. 442 o RESERVED: 20 bits. MUST be 0 on transmission and ignored on 443 receipt. 445 o Sequence Number: 28 bits, which is used for indicating sequence 446 number of a DetNet flow. 448 5.1.2. SRv6 Network Programming new Functions 450 New SRv6 Network Programming functions are defined as follows: 452 5.1.2.1. End. B.Replicatioreserve the value of argument field(Inherited 453 argument)of segment[0] of SRH n: Packet Replication Function 455 1. IF NH=SRH & SL>0 THEN 457 2. extract the DetNet TLV values from the SRH 459 3. create two new outer IPv6+SRH headers: IPv6-SRH-1 and IPv6-SRH-2 460 Insert the policy-instructed segment lists in each newly created 461 SRH (SRH-1 and SRH-2). Also, add the extracted DetNet TLVs into 462 SRH-1 and SRH-2. 464 4. remove the incoming outer IPv6+SRH header. 466 5. create a duplication of the incoming packet. 468 6. encapsulate the original packet into the first outer IPv6+SRH 469 header: (IPv6-SRH-1) (original packet) 471 7. encapsulate the duplicate packet into the second outer IPv6+SRH 472 header: (IPv6-SRH-2) (duplicate packet) 474 8. set the IPv6 SA as the local address of this node. 476 9. set the IPv6 DA of IPv6-SRH-1 to the first segment of the SRv6 477 Policy in of SRH-1 segment list. 479 10. set the IPv6 DA of IPv6-SRH-2 to the first segment of the SRv6 480 Policy in of SRH-2 segment list. 482 11. ELSE 484 12. drop the packet 486 5.1.2.2. End. B. Elimination: Packet Elimination Function 488 1. IF NH=SRH & SL>0 & "the packet is not a redundant packet" THEN 490 2. do not decrement SL nor update the IPv6 DA with SRH[SL] 492 3. extract the value of DetNet TLVs from the SRH 494 4. create a new outer IPv6+SRH header 496 5. insert the policy-instructed segment lists in the newly created 497 SRH and add the retrieved DetNet TLVs in the newly created SRH 499 6. remove the incoming outer IPv6+SRH header. 501 7. set the IPv6 DA to the first segment of the SRv6 Policy in the 502 newly created SRH 504 8. ELSE 506 9. drop the packet 508 5.2. SID Based SRv6 Data Plane Solution 510 5.2.1. Encapsulation 512 SRv6 SID can be represented as LOC:FUNCT:ARG::, where: 514 LOC, means "LOCATION" and defines the node associated with the SID 515 (i.e.: represented by the SID). 517 FUNCT, means "FUNCTION", and identifies the processing that the node 518 specified in LOC applies to the packet. 520 ARG, means "ARGUMENTS" and provides the additional arguments for the 521 function. New SID functions for DetNet is defined in section 5.2.2. 522 See [I-D.filsfils-spring-srv6-network-programming] for details on 523 SRV6 Network Programming. The SRH for DetNet in the outer IPv6 524 header is illustrated as follows 526 0 1 2 3 527 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 1 528 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 529 | Next Header | Hdr Ext Len | Routing Type | Segment Left | 530 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 531 | Last Entry | Flags | Tag | 532 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 533 | Location & Function | 534 | (Segment List[0] for relay node or edge node) | 535 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 536 | Location & Function | Flow Identification | 537 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 538 |Flow ID| Sequence Number | 539 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 540 | ... | 541 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 542 | | 543 | Segment List[n] | 544 | | 545 | | 546 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 547 | Optional TLVS | 548 | ... | 549 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 551 where: 553 o LOCATION&FUNCTION: the 80 most significant bits that are used for 554 routing the packet towards the LOCATION (as defined in 555 [I-D.filsfils-spring-srv6-network-programming]); 557 o FLOW IDENTIFICATION: 20 bits, in the DetNet TLVs in the SRH, used 558 for DetNet flow identification in the DetNet relay node; 560 o SEQUENCE NUMBER : 28 bits, in the DetNet TLVs, used for dis crime 561 packets in the same DetNet flow; 563 5.2.2. Functions 565 New SID functions are defined as follows: 567 5.2.2.1. End. B.Replication: Packet Replication Function 569 The function is similar as that has been defined in section 5.1.2.1. 570 The only difference is that instead of retrieving the TLV values, 571 this function retrieves the argument. 573 5.2.2.2. End. B. Elimination: Packet Elimination Function 575 The function is similar as that has been defined in section 5.1.2.2. 576 The only difference is that instead of retrieving the TLV values, 577 this function retrieves the argument. 579 5.3. DetNet SID Based SRv6 Data Plane Solution 581 5.3.1. Encapulation 583 A non-forwarding DetNet SID is defined to carry Flow Identification 584 and Sequence Number. 586 0 1 2 3 587 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 1 588 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 589 | Next Header | Hdr Ext Len | Routing Type | Segment Left | 590 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 591 | Last Entry | Flags | Tag | 592 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 593 | | 594 | Location & Function | 595 | (Segment List[0] for relay node or edge node) | 596 | | 597 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 598 | ... | 599 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 600 | | 601 | Segment List[n] | 602 | | 603 | | 604 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 605 | | 606 | DetNet SID | 607 | | 608 | | 609 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 610 | Optional TLVs | 611 | ... | 612 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 614 5.3.2. Functions 616 TBD 618 6. SRv6 DetNet Data Plane Solution for Transport Sub-layer 620 TBD 622 7. IANA Considerations 624 TBD 626 8. Security Considerations 628 TBD 630 9. Acknowledgements 632 Thank you for valuable comments from James Guichard and Andrew Mails. 634 10. Normative References 636 [I-D.filsfils-spring-srv6-network-programming] 637 Filsfils, C., Camarillo, P., Leddy, J., 638 daniel.voyer@bell.ca, d., Matsushima, S., and Z. Li, "SRv6 639 Network Programming", draft-filsfils-spring-srv6-network- 640 programming-07 (work in progress), February 2019. 642 [I-D.ietf-6man-segment-routing-header] 643 Filsfils, C., Dukes, D., Previdi, S., Leddy, J., 644 Matsushima, S., and d. daniel.voyer@bell.ca, "IPv6 Segment 645 Routing Header (SRH)", draft-ietf-6man-segment-routing- 646 header-21 (work in progress), June 2019. 648 [I-D.ietf-detnet-architecture] 649 Finn, N., Thubert, P., Varga, B., and J. Farkas, 650 "Deterministic Networking Architecture", draft-ietf- 651 detnet-architecture-13 (work in progress), May 2019. 653 [I-D.ietf-detnet-dp-sol-mpls] 654 Korhonen, J. and B. Varga, "DetNet MPLS Data Plane 655 Encapsulation", draft-ietf-detnet-dp-sol-mpls-02 (work in 656 progress), March 2019. 658 [I-D.ietf-spring-segment-routing-policy] 659 Filsfils, C., Sivabalan, S., daniel.voyer@bell.ca, d., 660 bogdanov@google.com, b., and P. Mattes, "Segment Routing 661 Policy Architecture", draft-ietf-spring-segment-routing- 662 policy-03 (work in progress), May 2019. 664 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 665 Requirement Levels", BCP 14, RFC 2119, 666 DOI 10.17487/RFC2119, March 1997, 667 . 669 [RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L., 670 Decraene, B., Litkowski, S., and R. Shakir, "Segment 671 Routing Architecture", RFC 8402, DOI 10.17487/RFC8402, 672 July 2018, . 674 Authors' Addresses 676 Xuesong Geng 677 Huawei 679 Email: gengxuesong@huawei.com 681 Mach(Guoyi) Chen 682 Huawei 684 Email: mach.chen@huawei.com 686 Yongqing Zhu 687 China Telecom 689 Email: zhuyq@gsta.com