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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 DetNet B. Varga, Ed. 3 Internet-Draft J. Farkas 4 Intended status: Standards Track Ericsson 5 Expires: May 24, 2020 L. Berger 6 D. Fedyk 7 LabN Consulting, L.L.C. 8 A. Malis 9 Independent 10 S. Bryant 11 Futurewei Technologies 12 J. Korhonen 13 November 21, 2019 15 DetNet Data Plane: MPLS 16 draft-ietf-detnet-mpls-04 18 Abstract 20 This document specifies the Deterministic Networking data plane when 21 operating over an MPLS Packet Switched Networks. 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 May 24, 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 . . . . . . . . . . . . . . . . . . . . . . . . 3 58 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 59 2.1. Terms Used in This Document . . . . . . . . . . . . . . . 3 60 2.2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 4 61 2.3. Requirements Language . . . . . . . . . . . . . . . . . . 5 62 3. DetNet MPLS Data Plane Overview . . . . . . . . . . . . . . . 5 63 3.1. Layers of DetNet Data Plane . . . . . . . . . . . . . . . 5 64 3.2. DetNet MPLS Data Plane Scenarios . . . . . . . . . . . . 6 65 4. MPLS-Based DetNet Data Plane Solution . . . . . . . . . . . . 8 66 4.1. DetNet Over MPLS Encapsulation Components . . . . . . . . 8 67 4.2. MPLS Data Plane Encapsulation . . . . . . . . . . . . . . 9 68 4.2.1. DetNet Control Word and the DetNet Sequence Number . 10 69 4.2.2. S-Labels . . . . . . . . . . . . . . . . . . . . . . 11 70 4.2.3. F-Labels . . . . . . . . . . . . . . . . . . . . . . 14 71 4.3. OAM Indication . . . . . . . . . . . . . . . . . . . . . 16 72 4.4. Flow Aggregation . . . . . . . . . . . . . . . . . . . . 17 73 4.4.1. Aggregation Via LSP Hierarchy . . . . . . . . . . . . 17 74 4.4.2. Aggregating DetNet Flows as a new DetNet flow . . . . 17 75 4.5. Service Sub-Layer Considerations . . . . . . . . . . . . 19 76 4.5.1. Edge Node Processing . . . . . . . . . . . . . . . . 19 77 4.5.2. Relay Node Processing . . . . . . . . . . . . . . . . 19 78 4.6. Forwarding Sub-Layer Considerations . . . . . . . . . . . 20 79 4.6.1. Class of Service . . . . . . . . . . . . . . . . . . 20 80 4.6.2. Quality of Service . . . . . . . . . . . . . . . . . 20 81 5. Management and Control Information Summary . . . . . . . . . 21 82 5.1. Service Sub-Layer Information Summary . . . . . . . . . . 21 83 5.1.1. Service Aggregation Information Summary . . . . . . . 22 84 5.2. Forwarding Sub-Layer Information Summary . . . . . . . . 23 85 6. Security Considerations . . . . . . . . . . . . . . . . . . . 24 86 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25 87 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 25 88 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 25 89 9.1. Normative References . . . . . . . . . . . . . . . . . . 25 90 9.2. Informative References . . . . . . . . . . . . . . . . . 27 91 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 29 93 1. Introduction 95 Deterministic Networking (DetNet) is a service that can be offered by 96 a network to DetNet flows. DetNet provides these flows extremely low 97 packet loss rates and assured maximum end-to-end delivery latency. 98 General background and concepts of DetNet can be found in [RFC8655]. 100 The DetNet Architecture models the DetNet related data plane 101 functions decomposed into two sub-layers: a service sub-layer and a 102 forwarding sub-layer. The service sub-layer is used to provide 103 DetNet service functions such as protection and reordering. The 104 forwarding sub-layer is used to provide forwarding assurance (low 105 loss, assured latency, and limited reordering). 107 This document specifies the DetNet data plane operation and the on- 108 wire encapsulation of DetNet flows over an MPLS-based Packet Switched 109 Network (PSN) using the service sub-layer reference model. MPLS 110 encapsulation already provides a solid foundation of building blocks 111 to enable the DetNet service and forwarding sub-layer functions. 112 MPLS encapsulated DetNet can be carried over a variety of different 113 network technologies that can provide the DetNet required level of 114 service. However, the specific details of how DetNet MPLS is carried 115 over different network technologies is out of scope of this document. 117 MPLS encapsulated DetNet flows can carry different types of traffic. 118 The details of the types of traffic that are carried in DetNet are 119 also out of scope of this document. An example of IP using DetNet 120 MPLS sub-networks can be found in [I-D.ietf-detnet-ip]. DetNet MPLS 121 may use an associated controller and Operations, Administration, and 122 Maintenance (OAM) functions that are defined outside of this 123 document. 125 Background information common to all data planes for DetNet can be 126 found in the DetNet Data Plane Framework 127 [I-D.ietf-detnet-data-plane-framework]. 129 2. Terminology 131 2.1. Terms Used in This Document 133 This document uses the terminology established in the DetNet 134 architecture [RFC8655] and the the DetNet Data Plane Framework 135 [I-D.ietf-detnet-data-plane-framework]. The reader is assumed to be 136 familiar with these documents and any terminology defined therein. 138 The following terminology is introduced in this document: 140 F-Label A Detnet "forwarding" label that identifies the LSP 141 used to forward a DetNet flow across an MPLS PSN, e.g., 142 a hop-by-hop label used between label switching routers 143 (LSR). 145 S-Label A DetNet "service" label that is used between DetNet 146 nodes that implement also the DetNet service sub-layer 147 functions. An S-Label is also used to identify a 148 DetNet flow at DetNet service sub-layer. 150 A-Label A special case of an S-Label, whose aggregation 151 properties are known only at the aggregation and 152 deaggregation end-points. 154 d-CW A DetNet Control Word (d-CW) is used for sequencing 155 information of a DetNet flow at the DetNet service sub- 156 layer. 158 2.2. Abbreviations 160 The following abbreviations are used in this document: 162 CoS Class of Service. 164 CW Control Word. 166 DetNet Deterministic Networking. 168 LSR Label Switching Router. 170 MPLS Multiprotocol Label Switching. 172 MPLS-TE Multiprotocol Label Switching - Traffic Engineering. 174 MPLS-TP Multiprotocol Label Switching - Transport Profile. 176 OAM Operations, Administration, and Maintenance. 178 PE Provider Edge. 180 PEF Packet Elimination Function. 182 PRF Packet Replication Function. 184 PREOF Packet Replication, Elimination and Ordering Functions. 186 POF Packet Ordering Function. 188 PSN Packet Switched Network. 190 PW PseudoWire. 192 QoS Quality of Service. 194 S-PE Switching Provider Edge. 196 T-PE Terminating Provider Edge. 198 TSN Time-Sensitive Network. 200 2.3. Requirements Language 202 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 203 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 204 "OPTIONAL" in this document are to be interpreted as described in BCP 205 14 [RFC2119] [RFC8174] when, and only when, they appear in all 206 capitals, as shown here. 208 3. DetNet MPLS Data Plane Overview 210 3.1. Layers of DetNet Data Plane 212 MPLS provides a wide range of capabilities that can be utilised by 213 DetNet. A straight forward approach utilizing MPLS for a DetNet 214 service sub-layer is based on the existing pseudowire (PW) 215 encapsulations and by utilizing existing MPLS Traffic Engineering 216 encapsulations and mechanisms. Background on PWs can be found in 217 [RFC3985] and [RFC3031]. Background on MPLS Traffic Engineering can 218 be found in [RFC3272] and [RFC3209]. 220 DetNet MPLS 221 . 222 Bottom of Stack . 223 (inner label) +------------+ 224 | Service | d-CW, S-Label (A-Label) 225 +------------+ 226 | Forwarding | F-Label(s) 227 +------------+ 228 Top of Stack . 229 (outer label) . 231 Figure 1: DetNet Adaptation to MPLS Data Plane 233 The DetNet MPLS data plane representation is illustrated in Figure 1. 234 The service sub-layer includes a DetNet control word (d-CW) and a 235 identifying service label (S-Label). The DetNet control word (d-CW) 236 conforms to the Generic PW MPLS Control Word (PWMCW) defined in 237 [RFC4385]. An aggregation label (A-Label) is a special case of 238 S-Label used for aggregation. 240 A node operating on a DetNet flow in the Detnet service sub- 241 layer,uses the local context associated with that S-Label, provided 242 by a received F-Label, to determine what local DetNet operation(s) 243 are applied to that packet. An S-Label may be taken from the 244 platform label space [RFC3031], making it unique, enabling DetNet 245 flow identification regardless of which input interface or LSP the 246 packet arrives on. 248 The DetNet forwarding sub-layer is supported by zero or more 249 forwarding labels (F-Labels). MPLS Traffic Engineering 250 encapsulations and mechanisms can be utilized to provide a forwarding 251 sub-layer that is responsible for providing resource allocation and 252 explicit routes. 254 3.2. DetNet MPLS Data Plane Scenarios 256 DetNet MPLS Relay Transit Relay DetNet MPLS 257 End System Node Node Node End System 258 (T-PE) (S-PE) (LSR) (S-PE) (T-PE) 259 +----------+ +----------+ 260 | Appl. |<------------ End to End Service ----------->| Appl. | 261 +----------+ +---------+ +---------+ +----------+ 262 | Service |<--| Service |-- DetNet flow --| Service |-->| Service | 263 +----------+ +---------+ +----------+ +---------+ +----------+ 264 |Forwarding| |Fwd| |Fwd| |Forwarding| |Fwd| |Fwd| |Forwarding| 265 +-------.--+ +-.-+ +-.-+ +----.---.-+ +-.-+ +-.-+ +---.------+ 266 : Link : / ,-----. \ : Link : / ,-----. \ 267 +........+ +-[ Sub ]-+ +......+ +-[ Sub ]-+ 268 [Network] [Network] 269 `-----' `-----' 270 |<- LSP -->| |<-------- LSP -----------| |<--- LSP -->| 272 |<----------------- DetNet MPLS --------------------->| 274 Figure 2: A DetNet MPLS Network 276 Figure 2 illustrates a hypothetical DetNet MPLS-only network composed 277 of DetNet aware MPLS enabled end systems, operating over a DetNet 278 aware MPLS network. In this figure, the relay nodes are PE devices 279 that define the MPLS LSP boundaries and the transit nodes are LSRs. 281 DetNet end system and relay nodes understand the particular needs of 282 DetNet flows and provide both DetNet service and forwarding sub-layer 283 functions. In the case of MPLS, DetNet service-aware nodes add, 284 remove and process d-CWs, S-Labels and F-labels as needed. DetNet 285 MPLS nodes provide functionality analogous to T-PEs when they sit at 286 the edge of an MPLS domain, and S-PEs when they are in the middle of 287 an MPLS domain, see [RFC6073]. 289 In a DetNet MPLS network, transit nodes may be DetNet service aware 290 or may be DetNet unaware MPLS Label Switching Routers (LSRs). In 291 this latter case, such LSRs would be unaware of the special 292 requirements of the DetNet service sub-layer, but would still provide 293 traffic engineering functions and the QoS capabilities needed to 294 ensure that the (TE) LSPs meet the service requirements of the 295 carried DetNet flows. 297 The application of DetNet using MPLS supports a number of control 298 plane/management plane types. These types support certain MPLS data 299 plane deployments. For example RSVP-TE, MPLS-TP, or MPLS Segment 300 Routing (when extended to support resource allocation) are all valid 301 MPLS deployment cases. 303 Figure 3 illustrates how an end-to-end MPLS-based DetNet service is 304 provided in a more detail. In this figure, the customer end systems, 305 CE1 and CE2, are able to send and receive MPLS encapsulated DetNet 306 flows, and R1, R2 and R3 are relay nodes in the middle of a DetNet 307 network. The 'X' in the end systems, and relay nodes represents 308 potential DetNet compound flow packet replication and elimination 309 points. In this example, service protection is supported utilizing 310 at least two DetNet member flows and TE LSPs. For a unidirectional 311 flow, R1 supports PRF and R3 supports PEF and POF. Note that the 312 relay nodes may change the underlying forwarding sub-layer, for 313 example tunneling MPLS over IEEE 802.1 TSN 314 [I-D.ietf-detnet-mpls-over-tsn], or simply over interconnect network 315 links. 317 DetNet DetNet 318 MPLS Service Transit Transit Service MPLS 319 DetNet | |<-Tnl->| |<-Tnl->| | DetNet 320 End | V 1 V V 2 V | End 321 System | +--------+ +--------+ +--------+ | System 322 +---+ | | R1 |=======| R2 |=======| R3 | | +---+ 323 | X...DFa...|._X_....|..DF1..|.__ ___.|..DF3..|...._X_.|.DFa..|.X | 324 |CE1|========| \ | | X | | / |======|CE2| 325 | | | | \_.|..DF2..|._/ \__.|..DF4..|._/ | | | | 326 +---+ | |=======| |=======| | +---+ 327 ^ +--------+ +--------+ +--------+ ^ 328 | Relay Node Relay Node Relay Node | 329 | (S-PE) (S-PE) (S-PE) | 330 | | 331 |<---------------------- DetNet MPLS --------------------->| 332 | | 333 |<--------------- End to End DetNet Service -------------->| 335 -------------------------- Data Flow -------------------------> 337 X = Optional service protection (none, PRF, PREOF, PEF/POF) 338 DFx = DetNet member flow x over a TE LSP 340 Figure 3: MPLS-Based Native DetNet 342 4. MPLS-Based DetNet Data Plane Solution 344 4.1. DetNet Over MPLS Encapsulation Components 346 To carry DetNet over MPLS the following is required: 348 1. A method of identifying the MPLS payload type. 350 2. A method of identifying the DetNet flow group to the processing 351 element. 353 3. A method of distinguishing DetNet OAM packets from DetNet data 354 packets. 356 4. A method of carrying the DetNet sequence number. 358 5. A suitable LSP to deliver the packet to the egress PE. 360 6. A method of carrying queuing and forwarding indication. 362 In this design an MPLS service label (the S-Label), similar to a 363 pseudowire (PW) label [RFC3985], is used to identify both the DetNet 364 flow identity and the payload MPLS payload type satisfying (1) and 365 (2) in the list above. OAM traffic discrimination happens through 366 the use of the Associated Channel method described in [RFC4385]. The 367 DetNet sequence number is carried in the DetNet Control word which 368 carries the Data/OAM discriminator. To simplify implementation and 369 to maximize interoperability two sequence number sizes are supported: 370 a 16 bit sequence number and a 28 bit sequence number. The 16 bit 371 sequence number is needed to support some types of legacy clients. 372 The 28 bit sequence number is used in situations where it is 373 necessary ensure that in high speed networks the sequence number 374 space does not wrap whilst packets are in flight. 376 The LSP used to forward the DetNet packet may be of any type (MPLS- 377 LDP, MPLS-TE, MPLS-TP [RFC5921], or MPLS-SR 378 [I-D.ietf-spring-segment-routing-mpls]). The LSP (F-Label) label 379 and/or the S-Label may be used to indicate the queue processing as 380 well as the forwarding parameters. Note that the possible use of 381 Penultimate Hop Popping (PHP) means that the S-Label may be the only 382 label received at the terminating DetNet service. 384 4.2. MPLS Data Plane Encapsulation 386 Figure 4 illustrates a DetNet data plane MPLS encapsulation. The 387 MPLS-based encapsulation of the DetNet flows is well suited for the 388 scenarios described in [I-D.ietf-detnet-data-plane-framework]. 389 Furthermore, an end to end DetNet service i.e., native DetNet 390 deployment (see Section 3.2) is also possible if DetNet end systems 391 are capable of initiating and termination MPLS encapsulated packets. 393 The MPLS-based DetNet data plane encapsulation consists of: 395 o DetNet control word (d-CW) containing sequencing information for 396 packet replication and duplicate elimination purposes, and the OAM 397 indicator. 399 o DetNet service Label (S-Label) that identifies a DetNet flow at 400 the receiving DetNet service sub-layer processing node. 402 o Zero or more Detnet MPLS Forwarding label(s) (F-Label) used to 403 direct the packet along the label switched path (LSP) to the next 404 service sub-layer processing node along the path. When 405 Penultimate Hop Popping is in use there may be no label F-Label in 406 the protocol stack on the final hop. 408 o The necessary data-link encapsulation is then applied prior to 409 transmission over the physical media. 411 DetNet MPLS-based encapsulation 413 +---------------------------------+ 414 | | 415 | DetNet App-Flow | 416 | Payload Packet | 417 | | 418 +---------------------------------+ <--\ 419 | DetNet Control Word | | 420 +---------------------------------+ +--> DetNet data plane 421 | S-Label | | MPLS encapsulation 422 +---------------------------------+ | 423 | [ F-Label(s) ] | | 424 +---------------------------------+ <--/ 425 | Data-Link | 426 +---------------------------------+ 427 | Physical | 428 +---------------------------------+ 430 Figure 4: Encapsulation of a DetNet App-Flow in an MPLS PSN 432 4.2.1. DetNet Control Word and the DetNet Sequence Number 434 A DetNet control word (d-CW) conforms to the Generic PW MPLS Control 435 Word (PWMCW) defined in [RFC4385]. The d-CW formatted as shown in 436 Figure 5 MUST be present in all DetNet packets containing app-flow 437 data. 439 0 1 2 3 440 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 1 441 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 442 |0 0 0 0| Sequence Number | 443 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 445 Figure 5: DetNet Control Word 447 (bits 0 to 3) 449 Per [RFC4385], MUST be set to zero (0). 451 Sequence Number (bits 4 to 31) 453 An unsigned value implementing the DetNet sequence number. 455 A separate sequence number space MUST be maintained by the node that 456 adds the d-CW for each DetNet app-flow. The following sequence 457 number field lengths MUST be supported: 459 0 bits 461 16 bits 463 28 bits 465 The sequence number length MUST be provisioned on a per app-flow 466 basis via configuration, i.e., via the controller plane described in 467 [I-D.ietf-detnet-data-plane-framework]. 469 A 0 bit sequence number field length indicates that there is no 470 DetNet sequence number used for the flow. When the length is zero, 471 the sequence number field MUST be set to zero (0) on all packets sent 472 for the flow. 474 When the sequence number field length is 16 or 28 bits for a flow, 475 the sequence number MUST be incremented by one for each new app-flow 476 packet sent. When the field length is 16 bits, d-CW bits 4 to 15 477 MUST be set to zero (0). The values carried in this field can wrap 478 and it is important to note that zero (0) is a valid field value. 479 For example, were the sequence number size is 16 bits, the sequence 480 will contain: 65535, 0, 1, where zero (0) is an ordinary sequence 481 number. 483 It is important to note that this document differs from [RFC4448] 484 where a sequence number of zero (0) is used to indicate that the 485 sequence number check algorithm is not used. 487 The sequence number is optionally used during receive processing as 488 described below in Section 4.2.2.1 and Section 4.2.2.2. 490 4.2.2. S-Labels 492 App-flow identification at a DetNet service sub-layer is realized by 493 an S-Label. MPLS-aware DetNet end systems and edge nodes, which are 494 by definition MPLS ingress and egress nodes, MUST add and remove an 495 app-flow specific d-CW and S-Label. Relay nodes MAY swap S-Label 496 values when processing an app-flow. 498 The S-Label value MUST be provisioned per app-flow via configuration, 499 e.g., via the controller plane described in 500 [I-D.ietf-detnet-data-plane-framework]. Note that S-Labels provide 501 app-flow identification at the downstream DetNet service sub-layer 502 receiver, not the sender. As such, S-Labels MUST be allocated by the 503 entity that controls the service sub-layer receiving node's label 504 space, and MAY be allocated from the platform label space [RFC3031]. 505 Because S-Labels are local to each node rather than being a global 506 identifier within a domain, they must be advertised to their upstream 507 DetNet service-aware peer nodes (e.g., a DetNet MPLS End System or a 508 DetNet Relay or Edge Node and interpreted in the context of their 509 received F-Label. 511 The S-Label will normally be at the bottom of the label stack once 512 the last F-Label is removed, immediately preceding the d-CW. To 513 support service sub-layer level OAM, an OAM Associated Channel Header 514 (ACH) [RFC4385] together with a Generic Associated Channel Label 515 (GAL) [RFC5586] MAY be used in place of a d-CW. 517 Similarly, an Entropy Label Indicator/Entropy Label (ELI/EL) 518 [RFC6790] MAY be carried below the S-Label in the label stack in 519 networks where DetNet flows would otherwise received ECMP treatment. 520 When ELs are used, the same EL value SHOULD be used for all of the 521 packets sent using a specific S-Label to force the flow to follow the 522 same path. However, as outlines in 523 [I-D.ietf-detnet-data-plane-framework] the use of ECMP for DetNet 524 flows is NOT RECOMMENDED. ECMP MAY be used for non-DetNet flows 525 within a DetNet domain. 527 When receiving a DetNet MPLS flow, an implementation MUST identify 528 the app-flow associated with the incoming packet based on the 529 S-Label. When a node is using platform labels for S-Labels, no 530 additional information is needed as the S-label uniquely identifies 531 the app-flow. In the case where platform labels are not used, zero 532 or more F-Labels and optionally, the incoming interface, proceeding 533 the S-Label MUST be used together with the S-Label to uniquely 534 identify the app-flows associated with a received packet. The 535 incoming interface MAY also be used to together with any present 536 F-Label(s) and the S-Label to uniquely identify an incoming app- 537 flows, for example, to in the case where PHP is used. Note that 538 choice to use platform label space for S-Label or S-Label plus one or 539 more F-Labels to identify app flows is a local implementation choice, 540 with one caveat. When one or more F-labels, or incoming interface, 541 is needed together with an S-Label to uniquely identify, the 542 controller plane MUST ensure that incoming DetNet MPLS packets arrive 543 with the needed information (F-label(s) and/or incoming interface); 544 the details of such are outside the scope of this document. 546 The use of platform labels for S-Labels matches other pseudowire 547 encapsulations for consistency but there is no hard requirement in 548 this regard. 550 4.2.2.1. Packet Elimination Function Processing 552 Implementations MAY support the Packet Elimination Function (PEF) for 553 received DetNet MPLS flows. When supported, use of the PEF for a 554 particular app-flow MUST be provisioned via configuration, e.g., via 555 the controller plane described in 556 [I-D.ietf-detnet-data-plane-framework]. 558 After an app-flow is identified for a received DetNet MPLS packet, as 559 described above, an implementation MUST check if PEF is configured 560 for that app-flow. When configured, the implementation MUST track 561 the sequence number contained in received d-CWs and MUST ensure that 562 duplicate (replicated) instances of a particular sequence number are 563 discarded. The specific mechanisms used for an implementation to 564 identify which received packets are duplicates and which are new is 565 an implementation choice. Note that per Section 4.2.1 the sequence 566 number field length may be 16 or 28 bits, and the field value can 567 wrap. 569 Note that an implementation MAY wish to constrain the maximum number 570 sequence numbers that are tracked, on platform-wide or per flow 571 basis. Some implementations MAY support the provisioning of the 572 maximum number sequence numbers that are tracked number on either a 573 platform-wide or per flow basis. 575 4.2.2.2. Packet Ordering Function Processing 577 A function that is related to in-order delivery is the Packet 578 Ordering Function (POF). Implementations MAY support POF. When 579 supported, use of the POF for a particular app-flow MUST be 580 provisioned via configuration, e.g., via the controller plane 581 described by [I-D.ietf-detnet-data-plane-framework]. Implementations 582 MAY required that PEF and POF be used in combination. There is no 583 requirement related to the order of execution of the Packet 584 Elimination and Ordering Functions in an implementation. 586 After an app-flow is identified for a received DetNet MPLS packet, as 587 described above, an implementation MUST check if POF is configured 588 for that app-flow. When configured, the implementation MUST track 589 the sequence number contained in received d-CWs and MUST ensure that 590 packets are processed in the order indicated in the received d-CW 591 sequence number field, which may not be in the order the packets are 592 received. As defined in Section 4.2.1 the sequence number field 593 length may be 16 or 28 bits, is incremented by one (1) for each new 594 app-flow packet sent, and the field value can wrap. The specific 595 mechanisms used for an implementation to identify the order of 596 received packets is an implementation choice. 598 Note that an implementation MAY wish to constrain the maximum number 599 of out of order packets that can be processed, on platform-wide or 600 per flow basis. Some implementations MAY support the provisioning of 601 this number on either a platform-wide or per flow basis. The number 602 of out of order packets that can be processed also impacts the 603 latency of a flow. 605 4.2.3. F-Labels 607 F-Labels are supported the DetNet forwarding sub-layer. F-Labels are 608 used to provide LSP-based connectivity between DetNet service sub- 609 layer processing nodes. 611 4.2.3.1. Service Sub-Layer and Packet Replication Function Processing 613 DetNet MPLS end systems, edge nodes and relay nodes may operate at 614 the DetNet service sub-layer with understand of app-flows and their 615 requirements. As mentioned earlier, when operating at this layer 616 such nodes can push, pop or swap (pop then push) S-Labels. In all 617 cases, the F-Labels used for the app-flow are always replaced and the 618 following procedures apply. 620 When sending a DetNet flow, zero or more F-Labels MAY be pushed on 621 top of an S-Label by the node pushing an S-Label. The F-Labels to be 622 pushed when sending a particular app-flow MUST be provisioned per 623 app-flow via configuration, e.g., via the controller plane discussed 624 in [I-D.ietf-detnet-data-plane-framework]. F-Labels can also provide 625 context for an S-Label. To allow for the omission of F-Labels, an 626 implementation SHOULD also allow an outgoing interface to be used. 628 The Packet Replication Function (PRF) function MAY be supported by an 629 implementation for outgoing DetNet flows. When replication is 630 supported, the same app-flow data will be sent over multiple outgoing 631 forwarding sub-layer LSPs. To support PRF an implementation MUST 632 support the setting of different sets of F-Labels. To allow for the 633 omission of F-Labels, an implementation SHOULD also allow multiple 634 outgoing interfaces to be provisioned. PRF MUST NOT be used with 635 app-flows configured with a d-CW sequence number field length of 0 636 bits. 638 When a single set of F-Labels is provisioned for a particular 639 outgoing app-flow, that set of F-labels MUST be pushed after the 640 S-Label is pushed. The outgoing packet is then forwarded as 641 described below in Section 4.2.3.2. When a single outgoing interface 642 is provisioned, the outgoing packet is then forwarded as described 643 below in Section 4.2.3.2. 645 When multiple sets of F-Labels or interfaces are provisioned for a 646 particular outgoing app-flow, a copy of the outgoing packet, 647 including the pushed S-Label, MUST be made per F-label set and 648 outgoing interface. Each set of provisioned F-Labels are then pushed 649 onto a copy of the packet. Each copy is then forwarded as described 650 below in Section 4.2.3.2. 652 As described in the previous section, when receiving a DetNet MPLS 653 flow, an implementation identifies the app-flow associated with the 654 incoming packet based on the S-Label. When a node is using platform 655 labels for S-Labels, any F-Labels can be popped and the S-label 656 uniquely identifies the app-flow. In the case where platform labels 657 are not used, F-Label(s) and, optionally, the incoming interface MUST 658 also be provisioned for incoming app-flows. The provisioned 659 information MUST then be used to identify incoming app-flows based on 660 the combination of S-Label and F-Label(s) or incoming interface. 662 4.2.3.2. Common F-Label Processing 664 All DetNet aware MPLS nodes process F-Labels as needed to meet the 665 service requirements of the DetNet flow or flows carried in the LSPs 666 represented by the F-Labels. This includes normal push, pop and swap 667 operations. Such processing is essentially the same type of 668 processing provided for TE LSPs, although the specific service 669 parameters, or traffic specification, can differ. When the DetNet 670 service parameters of the app-flow or flows carried in an LSP 671 represented by an F-Label can be met by an exiting TE mechanism, the 672 forwarding sub-layer processing node MAY be a DetNet unaware, i.e., 673 standard, MPLS LSR. Such TE LSPs may provide LSP forwarding service 674 as defined in, but not limited to, [RFC3209], [RFC3270], [RFC3272], 675 [RFC3473], [RFC4875], [RFC5440], and [RFC8306]. 677 More specifically, as mentioned above, the DetNet forwarding sub- 678 layer provides explicit routes and allocated resources, and F-Labels 679 are used to map to each. Explicit routes are supported based on the 680 topmost (outermost) F-Label that is pushed or swapped and the LSP 681 that corresponds to this label. This topmost (outgoing) label MUST 682 be associated with a provisioned outgoing interface and, for non- 683 point-to-point outgoing interfaces, a next hop LSR. Note that this 684 information MUST be provisioned via configuration or the controller 685 plane. In the previously mentioned special case where there are no 686 added F-labels and the outgoing interface is not a point-to-point 687 interface, the outgoing interface MUST also be associated with a next 688 hop LSR. 690 Resources may be allocated in a hierarchical fashion per LSP that is 691 represented by each F-Label. Each LSP MAY be provisioned with a 692 service parameters that dictates the specific traffic treatment to be 693 received by the traffic carried over that LSP. Implementations of 694 this document MUST ensure that traffic carried over each LSP 695 represented by one or more F-Labels receives the traffic treatment 696 provisioned for that LSP. Typical mechanisms used to provide 697 different treatment to different flows includes the allocation of 698 system resources (such as queues and buffers) and provisioning or 699 related parameters (such as shaping, and policing). Support can also 700 be provided via an underlying network technology such IEEE802.1 TSN 701 [I-D.ietf-detnet-mpls-over-tsn]. The specific mechanisms used by a 702 DetNet node to ensure DetNet service delivery requirements are met 703 for supported DetNet flows is outside the scope of this document. 705 Packets that are marked in a way that do not correspond to allocated 706 resources, e.g., lack a provisioned F-Label, can disrupt the QoS 707 offered to properly reserved DetNet flows by using resources 708 allocated to the reserved flows. Therefore, the network nodes of a 709 DetNet network: 711 o MUST defend the DetNet QoS by discarding or remarking (to an 712 allocated DetNet flow or non-competing non-DetNet flow) packets 713 received that are not associated with a completed resource 714 allocation. 716 o MUST NOT use a DetNet allocated resource, e.g. a queue or shaper 717 reserved for DetNet flows, for any packet that does match the 718 corresponding DetNet flow. 720 o MUST ensure a QoS flow does not exceed its allocated resources or 721 provisioned service level, 723 o MUST ensure a CoS flow or service class does not impact the 724 service delivered to other flows. This requirement is similar to 725 requirement for MPLS LSRs to that CoS LSPs do not impact the 726 resources allocated to TE LSPs, e.g., via [RFC3473]. 728 Subsequent sections provide additional considerations related to CoS 729 (Section 4.6.1), QoS (Section 4.6.2) and aggregation (Section 4.4). 731 4.3. OAM Indication 733 OAM follows the procedures set out in [RFC5085] with the restriction 734 that only Virtual Circuit Connectivity Verification (VCCV) type 1 is 735 supported. 737 As shown in Figure 3 of [RFC5085] when the first nibble of the d-CW 738 is 0x0 the payload following the d-CW is normal user data. However, 739 when the first nibble of the d-CW is 0X1, the payload that follows 740 the d-DW is an OAM payload with the OAM type indicated by the value 741 in the d-CW Channel Type field. 743 The reader is referred to [RFC5085] for a more detailed description 744 of the Associated Channel mechanism, and to the DetNet work on OAM 745 for more information DetNet OAM. 747 4.4. Flow Aggregation 749 The ability to aggregate individual flows, and their associated 750 resource control, into a larger aggregate is an important technique 751 for improving scaling of control in the data, management and control 752 planes. The DetNet data plane allows for the aggregation of DetNet 753 flows, to improved scaling. There are two methods of supporting flow 754 aggregation covered in this section. 756 The resource control and management aspects of aggregation (including 757 the configuration of queuing, shaping, and policing) are the 758 responsibility of the DetNet controller plane and is out of scope of 759 this documents. It is also the responsibility of the controller 760 plane to ensure that consistent aggregation methods are used. 762 4.4.1. Aggregation Via LSP Hierarchy 764 DetNet flows forwarded via MPLS can leverage MPLS-TE's existing 765 support for hierarchical LSPs (H-LSPs), see [RFC4206]. H-LSPs are 766 typically used to aggregate control and resources, they may also be 767 used to provide OAM or protection for the aggregated LSPs. Arbitrary 768 levels of aggregation naturally falls out of the definition for 769 hierarchy and the MPLS label stack [RFC3032]. DetNet nodes which 770 support aggregation (LSP hierarchy) map one or more LSPs (labels) 771 into and from an H-LSP. Both carried LSPs and H-LSPs may or may not 772 use the TC field, i.e., L-LSPs or E-LSPs. Such nodes will need to 773 ensure that individual LSPs and H-LSPs receive the traffic treatment 774 required to ensure the required DetNet service is preserved. 776 Additional details of the traffic control capabilities needed at a 777 DetNet-aware node may be covered in the new service definitions 778 mentioned above or in separate future documents. Controller plane 779 mechanisms will also need to ensure that the service required on the 780 aggregate flow are provided, which may include the discarding or 781 remarking mentioned in the previous sections. 783 4.4.2. Aggregating DetNet Flows as a new DetNet flow 785 An aggregate can be built by layering DetNet flows, including both 786 their S-Label and, when present, F-Labels as shown below: 788 +---------------------------------+ 789 | | 790 | DetNet Flow | 791 | Payload Packet | 792 | | 793 +---------------------------------+ <--\ 794 | DetNet Control Word | | 795 +=================================+ | 796 | S-Label | | 797 +---------------------------------+ | 798 | [ F-Label(s) ] | +----DetNet data plane 799 +---------------------------------+ | 800 | DetNet Control Word | | 801 +=================================+ | 802 | A-Label | | 803 +---------------------------------+ | 804 | F-Label(s) | <--/ 805 +---------------------------------+ 806 | Data-Link | 807 +---------------------------------+ 808 | Physical | 809 +---------------------------------+ 811 Figure 6: DetNet Aggregation as a new DetNet Flow 813 Both the aggregation label, which is referred to as an A-Label, and 814 the individual flow's S-Label have their MPLS S bit set indicating 815 bottom of stack, and the d-CW allows the PREOF to work. An A-Label 816 is a special case of an S-Label, whose properties are known only at 817 the aggregation and deaggregation end-points. 819 It is a property of the A-Label that what follows is a d-CW followed 820 by an MPLS label stack. A relay node processing the A-Label would 821 not know the underlying payload type, and the A-Label would be 822 process as a normal S-Label. This would only be known to a node that 823 was a peer of the node imposing the S-Label. However there is no 824 real need for it to know the payload type during aggregation 825 processing. 827 As in the previous section, nodes supporting this type of aggregation 828 will need to ensure that individual and aggregated flows receive the 829 traffic treatment required to ensure the required DetNet service is 830 preserved. Also, it is the controller plane's responsibility to to 831 ensure that the service required on the aggregate flow are properly 832 provisioned. 834 4.5. Service Sub-Layer Considerations 836 The edge and relay node internal procedures related to PREOF are 837 implementation specific. The order of a packet elimination or 838 replication is out of scope in this specification. 840 It is important that the DetNet layer is configured such that a 841 DetNet node never receives its own replicated packets. If it were to 842 receive such packets the replication function would make the loop 843 more destructive of bandwidth than a conventional unicast loop. 844 Ultimately the TTL in the S-Label will cause the packet to die during 845 a transient loop, but given the sensitivity of applications to packet 846 latency the impact on the DetNet application would be severe. To 847 avoid the problem of a transient forwarding loop, changes to an LSP 848 supporting DetNet MUST be loop-free. 850 4.5.1. Edge Node Processing 852 An edge node is responsible for matching ingress packets to the 853 service they require and encapsulating them accordingly. An edge 854 node may participate in the packet replication and duplicate packet 855 elimination. 857 The DetNet-aware forwarder selects the egress DetNet member flow 858 segment based on the flow identification. The mapping of ingress 859 DetNet member flow segment to egress DetNet member flow segment may 860 be statically or dynamically configured. Additionally the DetNet- 861 aware forwarder does duplicate frame elimination based on the flow 862 identification and the sequence number combination. The packet 863 replication is also done within the DetNet-aware forwarder. During 864 elimination and the replication process the sequence number of the 865 DetNet member flow MUST be preserved and copied to the egress DetNet 866 member flow. 868 The internal design of a relay node is out of scope of this document. 869 However the reader's attention is drawn to the need to make any PREOF 870 state available to the packet processor(s) dealing with packets to 871 which the PREOF functions must be applied, and to maintain that state 872 is such as way that it is available to the packet processor operation 873 on the next packet in the DetNet flow (which may be a duplicate, a 874 late packet, or the next packet in sequence. 876 4.5.2. Relay Node Processing 878 A DetNet Relay node operates in the DetNet forwarding sub-layer . 879 For DetNet using MPLS this processing is performed on the F-Label. 880 This processing is done within an extended forwarder function. 881 Whether an ingress DetNet member flow receives DetNet specific 882 processing depends on how the forwarding is programmed. Some relay 883 nodes may be DetNet service aware, while others may be unmodified 884 LSRs that only understand how to switch MPLS-TE LSPs. 886 It is also possible to treat the relay node as a transit node, see 887 Section 4.4. Again, this is entirely up to how the forwarding has 888 been programmed. 890 4.6. Forwarding Sub-Layer Considerations 892 4.6.1. Class of Service 894 Class and quality of service, i.e., CoS and QoS, are terms that are 895 often used interchangeably and confused with each other. In the 896 context of DetNet, CoS is used to refer to mechanisms that provide 897 traffic forwarding treatment based on aggregate group basis and QoS 898 is used to refer to mechanisms that provide traffic forwarding 899 treatment based on a specific DetNet flow basis. Examples of 900 existing network level CoS mechanisms include DiffServ which is 901 enabled by IP header differentiated services code point (DSCP) field 902 [RFC2474] and MPLS label traffic class field [RFC5462], and at Layer- 903 2, by IEEE 802.1p priority code point (PCP). 905 CoS for DetNet flows carried in PWs and MPLS is provided using the 906 existing MPLS Differentiated Services (DiffServ) architecture 907 [RFC3270]. Both E-LSP and L-LSP MPLS DiffServ modes MAY be used to 908 support DetNet flows. The Traffic Class field (formerly the EXP 909 field) of an MPLS label follows the definition of [RFC5462] and 910 [RFC3270]. The Uniform, Pipe, and Short Pipe DiffServ tunneling and 911 TTL processing models are described in [RFC3270] and [RFC3443] and 912 MAY be used for MPLS LSPs supporting DetNet flows. MPLS ECN MAY also 913 be used as defined in ECN [RFC5129] and updated by [RFC5462]. 915 4.6.2. Quality of Service 917 In addition to explicit routes, and packet replication and 918 elimination, described in Section 4 above, DetNet provides zero 919 congestion loss and bounded latency and jitter. As described in 920 [RFC8655], there are different mechanisms that maybe used separately 921 or in combination to deliver a zero congestion loss service. This 922 includes Quality of Service (QoS) mechanisms at the MPLS layer, that 923 may be combined with the mechanisms defined by the underlying network 924 layer such as 802.1TSN. 926 Quality of Service (QoS) mechanisms for flow specific traffic 927 treatment typically includes a guarantee/agreement for the service, 928 and allocation of resources to support the service. Example QoS 929 mechanisms include discrete resource allocation, admission control, 930 flow identification and isolation, and sometimes path control, 931 traffic protection, shaping, policing and remarking. Example 932 protocols that support QoS control include Resource ReSerVation 933 Protocol (RSVP) [RFC2205] (RSVP) and RSVP-TE [RFC3209] and [RFC3473]. 934 The existing MPLS mechanisms defined to support CoS [RFC3270] can 935 also be used to reserve resources for specific traffic classes. 937 A baseline set of QoS capabilities for DetNet flows carried in PWs 938 and MPLS can provided by MPLS with Traffic Engineering (MPLS-TE) 939 [RFC3209] and [RFC3473]. TE LSPs can also support explicit routes 940 (path pinning). Current service definitions for packet TE LSPs can 941 be found in "Specification of the Controlled Load Quality of 942 Service", [RFC2211], "Specification of Guaranteed Quality of 943 Service", [RFC2212], and "Ethernet Traffic Parameters", [RFC6003]. 944 Additional service definitions are expected in future documents to 945 support the full range of DetNet services. In all cases, the 946 existing label-based marking mechanisms defined for TE-LSPs and even 947 E-LSPs are use to support the identification of flows requiring 948 DetNet QoS. 950 5. Management and Control Information Summary 952 The specific information needed for the processing of each DetNet 953 service depends on the DetNet node type and the functions being 954 provided on the node. This section summarizes based on the DetNet 955 sub-layer and if the DetNet traffic is being sent or received. All 956 DetNet node types are DetNet forwarding sub-layer aware, while all 957 but transit nodes are service sub-layer aware. This is shown in 958 Figure 2. 960 Much like other MPLS labels, there are a number of alternatives 961 available for DetNet S-Label and F-Label advertisement to an upstream 962 peer node. These include distributed signaling protocols such as 963 RSVP-TE, centralized label distribution via a controller that manages 964 both the sender and the receiver using NETCONF/YANG, BGP, PCEP, etc., 965 and hybrid combinations of the two. The details of the controller 966 plane solution required for the label distribution and the management 967 of the label number space are out of scope of this document. There 968 are particular DetNet considerations and requirements that are 969 discussed in [I-D.ietf-detnet-data-plane-framework]. 971 5.1. Service Sub-Layer Information Summary 973 The following summarizes the information that is needed on service 974 sub-layer aware nodes that send DetNet MPLS traffic, on a per service 975 basis: 977 o App-Flow identification information, e.g., an incoming service on 978 a relay node or IP information as defined in 979 [I-D.ietf-detnet-ip-over-mpls]. 981 o The sequence number length to be used for the service. Valid 982 values included 0, 16 and 28 bits. 0 bits cannot be used when PRF 983 is configured for the service. 985 o The S-Label for the service. 987 o If PRF is to be provided for the service. 989 o The forwarding sub-layer information associated with the output of 990 the service sub-layer. Note that when the PRF function is 991 provisioned, this information is per DetNet member flow. 992 Logically the forwarding sub-layer information is a pointer to 993 further details of transmission of Detnet flows at the forwarding 994 sub-layer. 996 The following summarizes the information that is needed on service 997 sub-layer aware nodes that receives DetNet MPLS traffic, on a per 998 service basis: 1000 o The forwarding sub-layer information associated with the input of 1001 the service sub-layer. Note that when the PEF function is 1002 provisioned, this information is per DetNet member flow. 1003 Logically the forwarding sub-layer information is a pointer to 1004 further details of the reception of Detnet flows at the forwarding 1005 sub-layer or A-Label. 1007 o The S-Label for the received service. 1009 o If PEF or POF is to be provided for the service. 1011 o The sequence number length to be used for the service. Valid 1012 values included 0, 16 and 28 bits. 0 bits cannot be used when PEF 1013 or POF are configured for the service. 1015 5.1.1. Service Aggregation Information Summary 1017 Nodes performing aggregation using A-Labels, per 1018 Section Section 4.4.2, require the additional information summarized 1019 in this section. 1021 The following summarizes the information that is needed on a node 1022 that sends aggregated flows using A-Labels: 1024 o The S-Labels or F-Labels that are to be carried over each 1025 aggregated service. 1027 o The A-Label associated with each aggregated service. 1029 o The other S-Label information summarized above. 1031 On the receiving node, the A-Label provides the forwarding context of 1032 an incoming interface or an F-Label and is used in subsequent service 1033 or forwarding sub-layer receive processing, as appropriated. The 1034 related addition configuration that may be provided discussed 1035 elsewhere in this section. 1037 5.2. Forwarding Sub-Layer Information Summary 1039 The following summarizes the information that is needed on forwarding 1040 sub-layer aware nodes that send DetNet MPLS traffic, on a per 1041 forwarding sub-layer flow basis: 1043 o The outgoing F-Label stack to be pushed. The stack may include 1044 H-LSP labels. 1046 o The traffic parameters associated with a specific label in the 1047 stack. Note that there may be multiple sets of traffic paramters 1048 associated with specific labels in the stack, e.g., when H-LSPs 1049 are used. 1051 o Outgoing interface and, for unicast traffic, the next hop 1052 information. 1054 o Sub-network specific parameters on a technology specific basis. 1055 For example, see [I-D.ietf-detnet-mpls-over-tsn]. 1057 The following summarizes the information that is needed on forwarding 1058 sub-layer aware nodes that receive DetNet MPLS traffic, on a per 1059 forwarding sub-layer flow basis: 1061 o The incoming interface. For some implementations and deployment 1062 scenarios, this information may not be needed. 1064 o The incoming F-Label stack to be popped. The stack may include 1065 H-LSP labels. 1067 o How the incoming forwarding sub-layer flow is to be handled, i.e., 1068 forwarded as a transit node, or provided to the service sub-layer. 1070 It is the responsibility of the DetNet controller plane to properly 1071 provision both flow identification information and the flow specific 1072 resources needed to provided the traffic treatment needed to meet 1073 each flow's service requirements. This applies for aggregated and 1074 individual flows. 1076 6. Security Considerations 1078 Security considerations for DetNet are described in detail in 1079 [I-D.ietf-detnet-security]. General security considerations are 1080 described in [RFC8655]. This section considers exclusively security 1081 considerations which are specific to the DetNet MPLS data plane. 1083 Security aspects which are unique to DetNet are those whose aim is to 1084 provide the specific quality of service aspects of DetNet, which are 1085 primarily to deliver data flows with extremely low packet loss rates 1086 and bounded end-to-end delivery latency. 1088 The primary considerations for the data plane is to maintain 1089 integrity of data and delivery of the associated DetNet service 1090 traversing the DetNet network. Application flows can be protected 1091 through whatever means is provided by the underlying technology. For 1092 example, encryption may be used, such as that provided by IPSec 1093 [RFC4301] for IP flows and/or by an underlying sub-net using MACSec 1094 [IEEE802.1AE-2018] for IP over Ethernet (Layer-2) flows. 1096 From a data plane perspective this document does not add or modify 1097 any header information. 1099 At the management and control level DetNet flows are identified on a 1100 per-flow basis, which may provide controller plane attackers with 1101 additional information about the data flows (when compared to 1102 controller planes that do not include per-flow identification). This 1103 is an inherent property of DetNet which has security implications 1104 that should be considered when determining if DetNet is a suitable 1105 technology for any given use case. 1107 To provide uninterrupted availability of the DetNet service, 1108 provisions can be made against DOS attacks and delay attacks. To 1109 protect against DOS attacks, excess traffic due to malicious or 1110 malfunctioning devices can be prevented or mitigated, for example 1111 through the use of existing mechanism such as policing and shaping 1112 applied at the input of a DetNet domain. To prevent DetNet packets 1113 from being delayed by an entity external to a DetNet domain, DetNet 1114 technology definition can allow for the mitigation of Man-In-The- 1115 Middle attacks, for example through use of authentication and 1116 authorization of devices within the DetNet domain. 1118 7. IANA Considerations 1120 This document makes no IANA requests. 1122 8. Acknowledgements 1124 The authors wish to thank Pat Thaler, Norman Finn, Loa Anderson, 1125 David Black, Rodney Cummings, Ethan Grossman, Tal Mizrahi, David 1126 Mozes, Craig Gunther, George Swallow, Yuanlong Jiang and Carlos J. 1127 Bernardos for their various contributions to this work. 1129 9. References 1131 9.1. Normative References 1133 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 1134 Requirement Levels", BCP 14, RFC 2119, 1135 DOI 10.17487/RFC2119, March 1997, 1136 . 1138 [RFC2211] Wroclawski, J., "Specification of the Controlled-Load 1139 Network Element Service", RFC 2211, DOI 10.17487/RFC2211, 1140 September 1997, . 1142 [RFC2212] Shenker, S., Partridge, C., and R. Guerin, "Specification 1143 of Guaranteed Quality of Service", RFC 2212, 1144 DOI 10.17487/RFC2212, September 1997, 1145 . 1147 [RFC3031] Rosen, E., Viswanathan, A., and R. Callon, "Multiprotocol 1148 Label Switching Architecture", RFC 3031, 1149 DOI 10.17487/RFC3031, January 2001, 1150 . 1152 [RFC3032] Rosen, E., Tappan, D., Fedorkow, G., Rekhter, Y., 1153 Farinacci, D., Li, T., and A. Conta, "MPLS Label Stack 1154 Encoding", RFC 3032, DOI 10.17487/RFC3032, January 2001, 1155 . 1157 [RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., 1158 and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP 1159 Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001, 1160 . 1162 [RFC3270] Le Faucheur, F., Wu, L., Davie, B., Davari, S., Vaananen, 1163 P., Krishnan, R., Cheval, P., and J. Heinanen, "Multi- 1164 Protocol Label Switching (MPLS) Support of Differentiated 1165 Services", RFC 3270, DOI 10.17487/RFC3270, May 2002, 1166 . 1168 [RFC3443] Agarwal, P. and B. Akyol, "Time To Live (TTL) Processing 1169 in Multi-Protocol Label Switching (MPLS) Networks", 1170 RFC 3443, DOI 10.17487/RFC3443, January 2003, 1171 . 1173 [RFC3473] Berger, L., Ed., "Generalized Multi-Protocol Label 1174 Switching (GMPLS) Signaling Resource ReserVation Protocol- 1175 Traffic Engineering (RSVP-TE) Extensions", RFC 3473, 1176 DOI 10.17487/RFC3473, January 2003, 1177 . 1179 [RFC4206] Kompella, K. and Y. Rekhter, "Label Switched Paths (LSP) 1180 Hierarchy with Generalized Multi-Protocol Label Switching 1181 (GMPLS) Traffic Engineering (TE)", RFC 4206, 1182 DOI 10.17487/RFC4206, October 2005, 1183 . 1185 [RFC4385] Bryant, S., Swallow, G., Martini, L., and D. McPherson, 1186 "Pseudowire Emulation Edge-to-Edge (PWE3) Control Word for 1187 Use over an MPLS PSN", RFC 4385, DOI 10.17487/RFC4385, 1188 February 2006, . 1190 [RFC5085] Nadeau, T., Ed. and C. Pignataro, Ed., "Pseudowire Virtual 1191 Circuit Connectivity Verification (VCCV): A Control 1192 Channel for Pseudowires", RFC 5085, DOI 10.17487/RFC5085, 1193 December 2007, . 1195 [RFC5129] Davie, B., Briscoe, B., and J. Tay, "Explicit Congestion 1196 Marking in MPLS", RFC 5129, DOI 10.17487/RFC5129, January 1197 2008, . 1199 [RFC5462] Andersson, L. and R. Asati, "Multiprotocol Label Switching 1200 (MPLS) Label Stack Entry: "EXP" Field Renamed to "Traffic 1201 Class" Field", RFC 5462, DOI 10.17487/RFC5462, February 1202 2009, . 1204 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 1205 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 1206 May 2017, . 1208 9.2. Informative References 1210 [I-D.ietf-detnet-data-plane-framework] 1211 Varga, B., Farkas, J., Berger, L., Fedyk, D., Malis, A., 1212 Bryant, S., and J. Korhonen, "DetNet Data Plane 1213 Framework", draft-ietf-detnet-data-plane-framework-03 1214 (work in progress), October 2019. 1216 [I-D.ietf-detnet-ip] 1217 Varga, B., Farkas, J., Berger, L., Fedyk, D., Malis, A., 1218 Bryant, S., and J. Korhonen, "DetNet Data Plane: IP", 1219 draft-ietf-detnet-ip-03 (work in progress), October 2019. 1221 [I-D.ietf-detnet-ip-over-mpls] 1222 Varga, B., Farkas, J., Berger, L., Fedyk, D., Malis, A., 1223 Bryant, S., and J. Korhonen, "DetNet Data Plane: IP over 1224 MPLS", draft-ietf-detnet-ip-over-mpls-03 (work in 1225 progress), October 2019. 1227 [I-D.ietf-detnet-mpls-over-tsn] 1228 Varga, B., Farkas, J., Malis, A., and S. Bryant, "DetNet 1229 Data Plane: MPLS over IEEE 802.1 Time Sensitive Networking 1230 (TSN)", draft-ietf-detnet-mpls-over-tsn-01 (work in 1231 progress), October 2019. 1233 [I-D.ietf-detnet-security] 1234 Mizrahi, T., Grossman, E., Hacker, A., Das, S., Dowdell, 1235 J., Austad, H., and N. Finn, "Deterministic Networking 1236 (DetNet) Security Considerations", draft-ietf-detnet- 1237 security-06 (work in progress), November 2019. 1239 [I-D.ietf-spring-segment-routing-mpls] 1240 Bashandy, A., Filsfils, C., Previdi, S., Decraene, B., 1241 Litkowski, S., and R. Shakir, "Segment Routing with MPLS 1242 data plane", draft-ietf-spring-segment-routing-mpls-22 1243 (work in progress), May 2019. 1245 [IEEE802.1AE-2018] 1246 IEEE Standards Association, "IEEE Std 802.1AE-2018 MAC 1247 Security (MACsec)", 2018, 1248 . 1250 [RFC2205] Braden, R., Ed., Zhang, L., Berson, S., Herzog, S., and S. 1251 Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1 1252 Functional Specification", RFC 2205, DOI 10.17487/RFC2205, 1253 September 1997, . 1255 [RFC2474] Nichols, K., Blake, S., Baker, F., and D. Black, 1256 "Definition of the Differentiated Services Field (DS 1257 Field) in the IPv4 and IPv6 Headers", RFC 2474, 1258 DOI 10.17487/RFC2474, December 1998, 1259 . 1261 [RFC3272] Awduche, D., Chiu, A., Elwalid, A., Widjaja, I., and X. 1262 Xiao, "Overview and Principles of Internet Traffic 1263 Engineering", RFC 3272, DOI 10.17487/RFC3272, May 2002, 1264 . 1266 [RFC3985] Bryant, S., Ed. and P. Pate, Ed., "Pseudo Wire Emulation 1267 Edge-to-Edge (PWE3) Architecture", RFC 3985, 1268 DOI 10.17487/RFC3985, March 2005, 1269 . 1271 [RFC4301] Kent, S. and K. Seo, "Security Architecture for the 1272 Internet Protocol", RFC 4301, DOI 10.17487/RFC4301, 1273 December 2005, . 1275 [RFC4448] Martini, L., Ed., Rosen, E., El-Aawar, N., and G. Heron, 1276 "Encapsulation Methods for Transport of Ethernet over MPLS 1277 Networks", RFC 4448, DOI 10.17487/RFC4448, April 2006, 1278 . 1280 [RFC4875] Aggarwal, R., Ed., Papadimitriou, D., Ed., and S. 1281 Yasukawa, Ed., "Extensions to Resource Reservation 1282 Protocol - Traffic Engineering (RSVP-TE) for Point-to- 1283 Multipoint TE Label Switched Paths (LSPs)", RFC 4875, 1284 DOI 10.17487/RFC4875, May 2007, 1285 . 1287 [RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation 1288 Element (PCE) Communication Protocol (PCEP)", RFC 5440, 1289 DOI 10.17487/RFC5440, March 2009, 1290 . 1292 [RFC5586] Bocci, M., Ed., Vigoureux, M., Ed., and S. Bryant, Ed., 1293 "MPLS Generic Associated Channel", RFC 5586, 1294 DOI 10.17487/RFC5586, June 2009, 1295 . 1297 [RFC5921] Bocci, M., Ed., Bryant, S., Ed., Frost, D., Ed., Levrau, 1298 L., and L. Berger, "A Framework for MPLS in Transport 1299 Networks", RFC 5921, DOI 10.17487/RFC5921, July 2010, 1300 . 1302 [RFC6003] Papadimitriou, D., "Ethernet Traffic Parameters", 1303 RFC 6003, DOI 10.17487/RFC6003, October 2010, 1304 . 1306 [RFC6073] Martini, L., Metz, C., Nadeau, T., Bocci, M., and M. 1307 Aissaoui, "Segmented Pseudowire", RFC 6073, 1308 DOI 10.17487/RFC6073, January 2011, 1309 . 1311 [RFC6790] Kompella, K., Drake, J., Amante, S., Henderickx, W., and 1312 L. Yong, "The Use of Entropy Labels in MPLS Forwarding", 1313 RFC 6790, DOI 10.17487/RFC6790, November 2012, 1314 . 1316 [RFC8306] Zhao, Q., Dhody, D., Ed., Palleti, R., and D. King, 1317 "Extensions to the Path Computation Element Communication 1318 Protocol (PCEP) for Point-to-Multipoint Traffic 1319 Engineering Label Switched Paths", RFC 8306, 1320 DOI 10.17487/RFC8306, November 2017, 1321 . 1323 [RFC8655] Finn, N., Thubert, P., Varga, B., and J. Farkas, 1324 "Deterministic Networking Architecture", RFC 8655, 1325 DOI 10.17487/RFC8655, October 2019, 1326 . 1328 Authors' Addresses 1330 Balazs Varga (editor) 1331 Ericsson 1332 Magyar Tudosok krt. 11. 1333 Budapest 1117 1334 Hungary 1336 Email: balazs.a.varga@ericsson.com 1338 Janos Farkas 1339 Ericsson 1340 Magyar Tudosok krt. 11. 1341 Budapest 1117 1342 Hungary 1344 Email: janos.farkas@ericsson.com 1345 Lou Berger 1346 LabN Consulting, L.L.C. 1348 Email: lberger@labn.net 1350 Don Fedyk 1351 LabN Consulting, L.L.C. 1353 Email: dfedyk@labn.net 1355 Andrew G. Malis 1356 Independent 1358 Email: agmalis@gmail.com 1360 Stewart Bryant 1361 Futurewei Technologies 1363 Email: stewart.bryant@gmail.com 1365 Jouni Korhonen 1367 Email: jouni.nospam@gmail.com