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Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year == The document doesn't use any RFC 2119 keywords, yet seems to have RFC 2119 boilerplate text. -- The document date (April 23, 2020) is 1463 days in the past. Is this intentional? Checking references for intended status: Informational ---------------------------------------------------------------------------- == Outdated reference: A later version (-06) exists of draft-contreras-teas-slice-nbi-01 Summary: 1 error (**), 0 flaws (~~), 3 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group X. Geng 3 Internet-Draft J. Dong 4 Intended status: Informational Huawei Technologies 5 Expires: October 25, 2020 R. Pang 6 China Unicom 7 L. Han 8 China Mobile 9 T. Niwa 10 KDDI 11 J. Jin 12 LG U+ 13 C. Liu 14 China Unicom 15 N. Nageshar 16 Individual 17 April 23, 2020 19 5G End-to-end Network Slice Mapping from the view of Transport Network 20 draft-geng-teas-network-slice-mapping-01 22 Abstract 24 Network Slicing is one of the core featrures in 5G. End-to-end 25 network slice consists of 3 major types of network segments: Access 26 Network (AN), Mobile Core Network (CN) and Transport Network (TN). 27 This draft describes the procedure of mapping relationship between 5G 28 end-to-end network slice and transport network slice defined in IETF. 29 This draft also intends to expose some gaps in the existing network 30 management plane and data plane to support inter-domain network slice 31 mapping. Further work may require cooperation between IETF and 3GPP 32 (or other standard organizations). The definition of data model, 33 signaling protocol extension and new encapsulation are out of the 34 scope of this draft. 36 Requirements Language 38 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 39 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 40 document are to be interpreted as described in RFC 2119 [RFC2119]. 42 Status of This Memo 44 This Internet-Draft is submitted in full conformance with the 45 provisions of BCP 78 and BCP 79. 47 Internet-Drafts are working documents of the Internet Engineering 48 Task Force (IETF). Note that other groups may also distribute 49 working documents as Internet-Drafts. The list of current Internet- 50 Drafts is at https://datatracker.ietf.org/drafts/current/. 52 Internet-Drafts are draft documents valid for a maximum of six months 53 and may be updated, replaced, or obsoleted by other documents at any 54 time. It is inappropriate to use Internet-Drafts as reference 55 material or to cite them other than as "work in progress." 57 This Internet-Draft will expire on October 25, 2020. 59 Copyright Notice 61 Copyright (c) 2020 IETF Trust and the persons identified as the 62 document authors. All rights reserved. 64 This document is subject to BCP 78 and the IETF Trust's Legal 65 Provisions Relating to IETF Documents 66 (https://trustee.ietf.org/license-info) in effect on the date of 67 publication of this document. Please review these documents 68 carefully, as they describe your rights and restrictions with respect 69 to this document. Code Components extracted from this document must 70 include Simplified BSD License text as described in Section 4.e of 71 the Trust Legal Provisions and are provided without warranty as 72 described in the Simplified BSD License. 74 Table of Contents 76 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 77 2. Terminologies . . . . . . . . . . . . . . . . . . . . . . . . 3 78 3. Network Slice Mapping Structure . . . . . . . . . . . . . . . 4 79 3.1. Requirements Profile . . . . . . . . . . . . . . . . . . 5 80 3.2. Identifiers . . . . . . . . . . . . . . . . . . . . . . . 6 81 3.3. Relevant functions . . . . . . . . . . . . . . . . . . . 6 82 4. Network Slice Mapping Procedure . . . . . . . . . . . . . . . 7 83 4.1. Network Slice Mapping in Management Plane . . . . . . . . 8 84 4.2. Network Slice Mapping in Control Plane . . . . . . . . . 9 85 4.3. Network Slice Mapping in data plane . . . . . . . . . . . 9 86 4.3.1. Data Plane Mapping Considerations . . . . . . . . . . 10 87 4.3.2. Data Plane Mapping Design . . . . . . . . . . . . . . 10 88 5. Network Slice Mapping Summary . . . . . . . . . . . . . . . . 14 89 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15 90 7. Security Considerations . . . . . . . . . . . . . . . . . . . 15 91 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 15 92 9. Normative References . . . . . . . . . . . . . . . . . . . . 15 93 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16 95 1. Introduction 97 Driven by the new applications of 5G, the concept of network slicing 98 is defined to provide a logical network with specific capabilities 99 and characteristics. Network slice contains a set of network 100 functions and allocated resources(e.g. Computation, storage and 101 network resources). According to [TS28530], a 5G end-to-end network 102 slice is composed of three major types network segments: Radio Access 103 Network (RAN), Transport Network (TN) and Mobile Core Network (CN). 104 Transport network is supposed to provide the required connectivity 105 between AN and CN, which specific performance commitment. For each 106 end-to-end network slice, the topology and performance requirement 107 for transport network can be very different, which requires transport 108 network to have the capability of supporting multiple different 109 transport network slices. 111 A transport network slice is a virtual (logical) network with a 112 particular network topology and a set of shared or dedicated network 113 resources, which are used to provide the network slice consumer with 114 the required connectivity, appropriate isolation and specific Service 115 Level Agreement (SLA). A transport network slice could span multiple 116 technology (IP, Optical) and multiple administrative domains. 117 Depending on the consumer's requirement, a transport network slice 118 could be isolated from other concurrent transport network slices, in 119 terms of data plane, control plane and management plane. Transport 120 network slice is being defined and discussed in IETF. 122 Editor's Note: The work of 124 The procedure of end-to-end network slice instance creation, network 125 slice subnet instance creation and network slice instance termination 126 in management plane are defined in [TS28531]. The end-to-end network 127 slice allocation is defined in ETSI [ZSM003]. But there is no 128 specifications about how to map end-to-end network slice in 5G system 129 to transport network slice. This draft describes the procedure of 130 mapping 5G end-to-end network slice into transport network slice in 131 management plane, control plane and user plane. 133 2. Terminologies 135 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 136 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 137 document are to be interpreted as described in [RFC2119]. 139 The following terms are used in this document: 141 NS: Network Slice 142 NSI: Network Slice Instance 144 NSSI: Network Slice Subnet Instance 146 NSSAI: Network Slice Selection Assistance Information 148 S-NSSAI: Single Network Slice Selection Assistance Information 150 AN: Access Network 152 RAN: Radio Access Network 154 TN: Transport Network 156 CN: Mobile Core Network 158 DSCP: Differentiated Services Code Point 160 CSMF: Communication Service Management Function 162 NSMF: Network Slice Management Function 164 NSSMF: Network Slice Subnet Management Function 166 GST: General Slice Template 168 TNSII: Transport Network Slice Interworking Identifier 170 TNSI: Transport Network Slice Identifier 172 PDU: Protocol Data Unit 174 Editor's Note: Terminologies defined in 3GPP, e.g.,Network Slice 175 Subnet Management Function(NSSMF), Network Slice Subnet 176 Instance(NSSI) and Network Slice Selection Assistance 177 Information(NSSAI), is used in the end-to-end network slice mapping, 178 which may not be used necessarily within the transport network. 180 3. Network Slice Mapping Structure 182 The following figure shows the necessary elements for mapping end-to- 183 end network slice into transport network slice. All these network 184 slice elements are classified into three groups: requirements/ 185 capabilities, identifiers and relevant functions. 187 +-----------------+ 188 | CSMF | 189 +--------+--------+ 190 | 191 +--------V--------+ 192 | NSMF | 193 +-----------------+ 194 +----------| NSI Identifier |----------+ 195 | | Service Profile | | 196 | | TN Network- | | 197 | | -Slice Profile | | 198 | +-----------------+ | 199 | | | 200 +------V------+ +----------V----------+ +------V------+ 201 | AN NSSMF | | TN NSSMF | | CN NSSMF | 202 +-------------+ +---------------------+ +-------------+ 203 | AN-NSSI- | | TN-NSSI Identifier | | CN-NSSI- | 204 | -Identifier | | Function Management| | -Identifier | 205 | ... | | ... | | ... | Management 206 +-------------+ +---------------------+ +-------------+ Plane 207 | | | | ----------------- 208 |<----------PDU session (S-NSSAI)---------->| Control 209 | | | | Plane 210 V V V V ----------------- 211 /\ +-----+ +-----+ +-------+ Data 212 /AN\ -----| PE |-----...-----| PE |----| UPF | Plane 213 /____\ +-----+ +-----+ +-------+ 214 |-->TNSII<--|------>TNSI<-------|-->TNSII<--| 216 3.1. Requirements Profile 218 In order to satisfy a tenant's request for a network slice with 219 certain characteristics, creating a new network slice or using 220 existing network slice instance is constrained by the customer's 221 requirement and the capability of the network slices. 223 o Service Profile: represents the properties of network slice 224 related requirement that should be supported by the network slice 225 instance in 5G network. Service profile is defined in [TS28541] 226 6.3.3. 228 o TN Network Slice Profile: represents the properties of transport 229 network slice related requirement that should be supported by the 230 transport network slice in a 5G network. Slice Profile is defined 231 in [TS28541] 6.3.4. TN Network slice profile is newly defined in 232 this draft. 234 3.2. Identifiers 236 Network slice related identifiers in management plane, control plane 237 and user(data) plane play an important role in end-to-end network 238 slice mapping. 240 o Single Network Slice Selection Assistance Information(S-NSSAI): 241 end-to-end network slice identifier in control plane, which is 242 defined in [TS23501]; 244 o Network Slice Instance(NSI) Identifier:end-to-end network slice 245 identifier in management plane, which is created in NSMF; NSI is 246 is set of Network Function instances and the required resources 247 (e.g. compute, storage and networking resources) which form a 248 deployed Network Slice, which is defined in [TS23501]; ; 250 o Transport Network Slice Instance(TN-NSSI) Identifier: transport 251 network slice identifier in management plane, which is created in 252 TN NSSMF; TN-NSSI is newly defined in this draft. 254 o Transport Network Slice Interworking Identifier (TNSII): network 255 slice identifier which is used for mapping end-to-end network 256 slice into transport network slice in user plane. TNSII is newly 257 defined in this draft. 259 o Transport Network Slice Identifier(TNSI): transport network slice 260 identifier in data plane(user plane). TNSI is newly defined in 261 this draft. 263 The relationship between these identifiers are specifies in the 264 following sections. 266 3.3. Relevant functions 268 There are a set of slice relevant functions that are necessary for 269 transport network slice management: 271 o Topology management 273 o QoS management 275 o Resource management 277 o Measurement management 279 o ... 281 Some of these functions are implemented inside the transport network 282 and independent from the end-to-end network slice, e.g., topology 283 management, QoS management, resource management; Some of the 284 functions are related to the end-to-end network slice and should 285 cooperate with other network elements from other domain, e.g., 286 Measurement management. 288 4. Network Slice Mapping Procedure 290 This section provides a general procedure of network slice mapping: 292 +--------------------------------+ 293 | Requirement Matching | 294 +---------------+----------------+ 295 | 296 V 297 +--------------------------------+ 298 | NSI<->TN NSSI Mapping | 299 +---------------+----------------+ 300 | 301 V 302 +--------------------------------+ 303 | S-NSSAI Selection | 304 +---------------+----------------+ 305 | 306 V 307 +--------------------------------+ 308 |S-NSSAI<---------->TNSII Mapping| 309 | (NSI<->TN NSSI) | 310 +---------------+----------------+ 311 | 312 V 313 +--------------------------------+ 314 | TNSII<->TNSI Mapping | 315 +--------------------------------+ 317 1. NSMF receives the request from CSMF for allocation of a network 318 slice instance with certain characteristics. 320 2. Based on the service requirement , NSMF acquires requirements for 321 the end-to-end network slice instance , which is defined in Service 322 Profile([TS28541] section 6.3.3). 324 3. NSMF derives transport network slice related requirements from 325 the Service profile, and maintains them in Transport Network Slice 326 Profile, So as to CN Slice Profile and AN Slice Profile, in order to 327 decide on the constituent NSSIs(including AN NSSI, CN NSSI and TN 328 NSSI) of the NSI, based on the service profile and the endpoint 329 information(AN/CN edge nodes). 331 4. NSMF sends the Transport Network Slice Profile to TN NSSMF for TN 332 NSSI allocation. 334 5. TN NSSMF allocates TN NSSI which could satisfy the requirement of 335 Transport Network Slice Profile between the specified endpoints (AN/ 336 CN edge nodes) and sends the TN NSSI Identifier to NSMF. 338 6. NSMF acquires the mapping relationship between NSI and TN NSSI. 340 7. NSMF matains the mapping relationship between NSI and S-NSSAI and 341 the mapping relationship between TN NSSI and TNSII, which could be 342 used to set up mapping relationship between S-NSSAI and TNSII. 344 8. When a PDU session is set up between AN and CN, an S-NSSAI is 345 slected for the PDU session. 347 9. AN/CN edge nodes encapsulate the packet using TNSII, according to 348 the selected S-NSSAI. Network Slice could also be differentiated by 349 physical interface, if different network slices are transported 350 through different interface; 352 10. The edge node of transport network parses the TNSII from the 353 packet and maps the packet to the corresponding transport network 354 slice. It may encapsulate packet with TNSI. The nodes in transport 355 network transit the packet inside the corresponding transport network 356 slice according to TNSI. 358 The procedure of end-to-end network slice mapping involves the 359 mapping in three network planes: management plane, control plane and 360 data plane. 362 4.1. Network Slice Mapping in Management Plane 364 The transport network management Plane maintains the interface 365 between NSMF and TN NSSMF, which 1) guarantees that transport network 366 slice could connect the AN and CN with specified characteristics that 367 satisfy the requirements of communication; 2) builds up the mapping 368 relationship between NSI identifier and TN NSSI identifier; 3) 369 maintains the end-to-end slice relevant functions; 371 Service Profile defined in[TS28541] represents the requirement of 372 end-to-end network slice instance in 5G network. Parameters defined 373 in Service Profile include Latency, resource sharing level, 374 availability and so on. How to decompose the end-to-end requirement 375 to the transport network requirement is one of the key issues in 376 Network slice requirement mapping. GSMA(Global System for Mobile 377 Communications Association) defines the [GST] to indicate the network 378 slice requirement from the view of service provider. 379 [I-D.contreras-teas-slice-nbi] analysis the parameters of GST and 380 categorize the parameters into three classes, including the 381 attributes with direct impact on the transport network slice 382 definition. It is a good start for selecting the transport network 383 relevant parameters in order to define Network Slice Profile for 384 Transport Network. Network slice requirement parameters are also 385 necessary for the definition of transport network northbound 386 interface. 388 Inside the TN NSSMF, it is supposed to maintain the attributes of the 389 transport network slice. If the attributes of an existing TN NSSI 390 could satisfy the requirement from TN Network Slice Profile, the 391 existing TN NSSI could be selected and the mapping is finished If 392 there is no existing TN NSSI which could satisfy the requirement, a 393 new TN NSSI is supposed to be created by the NSSMF with new 394 attributes. 396 TN NSSI resource reservation should be considered to avoid over 397 allocation from multiple requests from NSMF (but the detailed 398 mechanism should be out of scope in the draft) 400 TN NSSMF sends the selected or newly allocated TN NSSI identifier to 401 NSMF. The mapping relationship between NSI identifier and TN NSSI 402 identifier is maintained in both NSMF and TN NSSMF. 404 4.2. Network Slice Mapping in Control Plane 406 There is no explicit interaction between transport network and AN/CN 407 in the control plane, but the S-NSSAI defined in [TS23501] is treated 408 as the end-to-end network slice identifier in the control plane of AN 409 and CN, which is used in UE registration and PDU session setup. In 410 this draft, we assume that there is mapping relationship between 411 S-NSSAI and NSI in the management plane, thus it could be mapped to a 412 transport network slice . 414 Editor's note: The mapping relationship between NSI defined in 415 [TS23501] and S-NSSAI defined in [TS23501] is still in discussion. 417 4.3. Network Slice Mapping in data plane 419 If multiple network slices are carried through one physical interface 420 between AN/CN and TN, transport network slice interworking 421 identifier(TNSII) in the data plane needs to be introduced. If 422 different network slices are transported through different physical 423 interfaces, Network Slices could be distinguished by the interface 424 directly. Thus TNSII is not the only option for network slice 425 mapping, while it may help in introducing new network slices. 427 4.3.1. Data Plane Mapping Considerations 429 The mapping relationship between AN or CN network slice identifier 430 (either S-NSSAI in control plane or NSI/NSSI in management plane) and 431 TNSII needs to be maintained in AN/CN network nodes, and the mapping 432 relationship between TNSII and TNSI is maintained in the edge node of 433 transport network. When the packet of a uplink flow goes from AN to 434 TN, the packet is encapsulated based on the TNSII; then the 435 encapsulation of TNSII is read by the edge node of transport network, 436 which maps the packet to the corresponding transport network slice. 438 Editor's Note: We have considered to add "Network Instance" defined 439 in [TS23501]in the draft. However, after the discussion with 3GPP 440 people, we think the concept of "network instance" is a 'neither 441 Necessary nor Sufficient Condition' for network slice. Network 442 Instance could be determined by S-NSSAI, it could also depends on 443 other information; Network slice could also be allocated without 444 network instance (in my understanding) And, TNSII is not a 445 competitive concept with network instance.TNSII is a concept for the 446 data plane interconnection with transport network, network instance 447 may be used by AN and CN nodes to associate a network slice with 448 TNSII 450 4.3.2. Data Plane Mapping Design 452 The following picture shows the end-to-end network slice in data 453 plane: 455 +--+ +-----+ +----------------+ 456 |UE|- - - -|(R)AN|---------------------------| UPF | 457 +--+ +-----+ +----------------+ 458 |<----AN NS---->|<----------TN NS---------->|<----CN NS----->| 460 The mapping between 3GPP slice and transport slice in user plane 461 could happens in: 463 (R)AN: User data goes from (radio) access network to transport 464 network 466 UPF: User data goes from core network functions to transport network 468 Editor's Note: As figure 4.7.1. in [TS28530] describes, TN NS will 469 not only exist between AN and CN but may also within AN NS and CN NS. 471 However, here we just show the TN between AN and CN as an example to 472 avoid unncessary complexity. 474 The following picture shows the user plane protocol stack in end-to- 475 end 5G system. 477 +-----------+ | | | 478 |Application+--------------------|------------------|---------------| 479 +-----------+ | | +-----------+ | 480 | PDU Layer +--------------------|------------------|-| PDU Layer | | 481 +-----------+ +-------------+ | +-------------+ | +-----------+ | 482 | | | ___Relay___ |--|--| ___Relay___ |-|-| | | 483 | | | \/ GTP-U|--|--|GTP-U\/ GTP-U|-|-| GTP-U | | 484 | 5G-AN | |5G-AN +------+ | +------+------+ | +-----------+ | 485 | Protocol | |Protoc|UDP/IP|--|--|UDP/IP|UDP/IP|-|-| UDP/IP | | 486 | Layers | |Layers+------+ | +------+------+ | +-----------+ | 487 | | | | L2 |--|--| L2 | L2 |-|-| L2 | | 488 | | | +------+ | +------+------+ | +-----------+ | 489 | | | | L1 |--|--| L1 | L1 |-|-| L1 | | 490 +-----------+ +-------------+ | +-------------+ | +-----------+ | 491 UE 5G-AN | UPF | UPF | 492 N3 N9 N6 494 The following figure shows the typical encapsulation in N3 interface 495 which could be used to carry the transport network slice interworking 496 identifier (TNSII) between AN/CN and TN. 498 +------------------------+ 499 | Application Protocols | 500 +------------------------+ 501 | IP (User) | 502 +------------------------+ 503 | GTP | 504 +------------------------+ 505 | UDP | 506 +------------------------+ 507 | IP | 508 +------------------------+ 509 | Ethernet | 510 +------------------------+ 512 4.3.2.1. Layer 3 and Layer 2 Encapsulations 514 If the encapsulation above IP layer is not visible to Transport 515 Network, it is not able to be used for network slice interworking 516 with transport network. In this case, IP header and Ethernet header 517 could be considered to provide information of network slice 518 interworking from AN or CN to TN. 520 +------------------------+----------- 521 | Application Protocols | ^ 522 +------------------------+ | 523 | IP (User) | Invisible 524 +------------------------+ for 525 | GTP | TN 526 +------------------------+ | 527 | UDP | V 528 +------------------------+------------ 529 | IP | 530 +------------------------+ 531 | Ethernet | 532 +------------------------+ 534 The following field in IP header and Ethernet header could be 535 considered : 537 IP Header: 539 o DSCP: It is traditionally used for the mapping of QoS identifier 540 between AN/CN and TN network. Although some values (e.g. The 541 unassigned code points) may be borrowed for the network slice 542 interworking, it may cause confusion between QoS mapping and 543 network slicing mapping.; 545 o Destination Address: It is possible to allocate different IP 546 addresses for entities in different network slice, then the 547 destination IP address could be used as the network slice 548 interworking identifier. However, it brings additional 549 requirement to IP address planning. In addition, in some cases 550 some AN or CN network slices may use duplicated IP addresses. 552 o Option fields/headers: It requires that both AN and CN nodes can 553 support the encapsulation and decapsulation of the options. 555 Ethernet header 557 o VLAN ID: It is widely used for the interconnection between AN/CN 558 nodes and the edge nodes of transport network for the access to 559 different VPNs. One possible problem is that the number of VLAN 560 ID can be supported by AN nodes is typically limited, which 561 effects the number of transport network slices a AN node can 562 attach to. Another problem is the total amount of VLAN ID (4K) 563 may not provide a comparable space as the network slice 564 identifiers of mobile networks. 566 Two or more options described above may also be used together as the 567 TNSII, while it would make the mapping relationship more complex to 568 maintain. 570 In some other case, when AN or CN could support more layer 3 571 encapsulations, more options are available as follows: 573 If the AN or CN could support MPLS, the protocol stack could be as 574 follows: 576 +------------------------+----------- 577 | Application Protocols | ^ 578 +------------------------+ | 579 | IP (User) | Invisible 580 +------------------------+ for 581 | GTP | TN 582 +------------------------+ | 583 | UDP | V 584 +------------------------+------------ 585 | MPLS | 586 +------------------------+ 587 | IP | 588 +------------------------+ 589 | Ethernet | 590 +------------------------+ 592 A specified MPLS label could be used to as a TNSII. 594 If the AN or CN could support SRv6, the protocol stack is as follows: 596 +------------------------+----------- 597 | Application Protocols | ^ 598 +------------------------+ | 599 | IP (User) | Invisible 600 +------------------------+ for 601 | GTP | TN 602 +------------------------+ | 603 | UDP | V 604 +------------------------+------------ 605 | SRH | 606 +------------------------+ 607 | IPv6 | 608 +------------------------+ 609 | Ethernet | 610 +------------------------+ 612 The following field could be considered to identify a network slice: 614 SRH: 616 o SRv6 functions: AN/CN is supposed to support the new function 617 extension of SRv6. 619 o Optional TLV: AN/CN is supposed to support the extension of 620 optional TLV of SRH. 622 4.3.2.2. Above Layer 3 Encapsulations 624 If the encapsulation above IP layer is visible to Transport Network, 625 it is able to be used to identify a network slice. In this case, UPD 626 and GTP-U could be considered to provide information of network slice 627 interworking between AN or CN and TN. 629 +------------------------+---------- 630 | Application Protocols | | 631 +------------------------+ Invisible 632 | IP (User) | for 633 +------------------------+ TN 634 | GTP | | 635 +------------------------+------------ 636 | UDP | 637 +------------------------+ 638 | IP | 639 +------------------------+ 640 | Ethernet | 641 +------------------------+ 643 The following field in UDP header could be considered: 645 UDP Header: 647 o UDP Source port: The UDP source port is sometimes used for load 648 balancing. Using it for network slice mapping would require to 649 disable the load-balancing behavior. 651 5. Network Slice Mapping Summary 653 The following picture shows the mapping relationship between the 654 network slice identifier in management plane, control plane and user 655 plane. 657 AN/CN | TN 658 Management +---------+ | +---------+ 659 Plane | NSI |<--------|------->| TN NSSI | 660 +---------+ | +---------+ 661 | | | 662 | | | 663 Control +-----V-----+ | +----------+----------+ 664 Plane | S-NSSAI | | | | 665 +-----------+ | | | 666 | +----V----+ +----V----+ 667 +----------->| TNSII |<--------->| TNSI | 668 User | /Port |<--------->| | 669 Plane +---------+ +---------+ 670 | 672 6. IANA Considerations 674 TBD 676 Note to RFC Editor: this section may be removed on publication as an 677 RFC. 679 7. Security Considerations 681 TBD 683 8. Acknowledgements 685 The authors would like to thank Shunsuke Homma for reviewing the 686 draft and giving valuable comments. 688 9. Normative References 690 [GST] "Generic Network Slice Template", 691 . 694 [I-D.contreras-teas-slice-nbi] 695 Contreras, L., Homma, S., and J. Ordonez-Lucena, 696 "Considerations for defining a Transport Slice NBI", 697 draft-contreras-teas-slice-nbi-01 (work in progress), 698 March 2020. 700 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 701 Requirement Levels", BCP 14, RFC 2119, 702 DOI 10.17487/RFC2119, March 1997, 703 . 705 [TS23501] "3GPP TS23.501", 706 . 709 [TS28530] "3GPP TS28.530", 710 . 713 [TS28531] "3GPP TS28.531", 714 . 717 [TS28541] "3GPP TS 28.541", 718 . 721 [ZSM003] "ETSI ZSM003", 722 . 725 Authors' Addresses 727 Xuesong Geng 728 Huawei Technologies 730 Email: gengxuesong@huawei.com 732 Jie Dong 733 Huawei Technologies 735 Email: jie.dong@huawei.com 737 Ran Pang 738 China Unicom 740 Email: pangran@chinaunicom.cn 742 Liuyan Han 743 China Mobile 745 Email: hanliuyan@chinamobile.com 746 Tomonobu Niwa 747 KDDI 749 Email: to-niwa@kddi.com 751 Jaehwan Jin 752 LG U+ 754 Email: daenamu1@lguplus.co.kr 756 Chang Liu 757 China Unicom 759 Email: liuc131@chinaunicom.cn 761 Nikesh Nageshar 762 Individual 764 Email: nikesh.nageshar@gmail.com