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2 Network Working Group X. Geng
3 Internet-Draft J. Dong
4 Intended status: Informational Huawei Technologies
5 Expires: January 14, 2021 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 July 13, 2020
19 5G End-to-end Network Slice Mapping from the view of Transport Network
20 draft-geng-teas-network-slice-mapping-02
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 January 14, 2021.
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 . . . . . . . . . . . 10
86 4.3.1. Data Plane Mapping Considerations . . . . . . . . . . 10
87 4.3.2. Data Plane Mapping Design . . . . . . . . . . . . . . 10
88 5. Network Slice Mapping Summary . . . . . . . . . . . . . . . . 15
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, endpoint
332 information, along with other TS NBI attributes to TN NSSMF for TN
333 NSSI allocation.
335 5. TN NSSMF allocates TN NSSI which could satisfy the requirement of
336 Transport Network Slice Profile between the specified endpoints (AN/
337 CN edge nodes) and sends the TN NSSI Identifier to NSMF.
339 6. NSMF acquires the mapping relationship between NSI and TN NSSI.
341 7. NSMF matains the mapping relationship between NSI and S-NSSAI and
342 the mapping relationship between TN NSSI and TNSII, which could be
343 used to set up mapping relationship between S-NSSAI and TNSII.
345 8. When a PDU session is set up between AN and CN, an S-NSSAI is
346 slected for the PDU session.
348 9. AN/CN edge nodes encapsulate the packet using TNSII, according to
349 the selected S-NSSAI. Network Slice could also be differentiated by
350 physical interface, if different network slices are transported
351 through different interface;
353 10. The edge node of transport network parses the TNSII from the
354 packet and maps the packet to the corresponding transport network
355 slice. It may encapsulate packet with TNSI. The nodes in transport
356 network transit the packet inside the corresponding transport network
357 slice according to TNSI.
359 The procedure of end-to-end network slice mapping involves the
360 mapping in three network planes: management plane, control plane and
361 data plane.
363 4.1. Network Slice Mapping in Management Plane
365 The transport network management Plane maintains the interface
366 between NSMF and TN NSSMF, which 1) guarantees that transport network
367 slice could connect the AN and CN with specified characteristics that
368 satisfy the requirements of communication; 2) builds up the mapping
369 relationship between NSI identifier and TN NSSI identifier; 3)
370 maintains the end-to-end slice relevant functions;
372 Service Profile defined in[TS28541] represents the requirement of
373 end-to-end network slice instance in 5G network. Parameters defined
374 in Service Profile include Latency, resource sharing level,
375 availability and so on. How to decompose the end-to-end requirement
376 to the transport network requirement is one of the key issues in
377 Network slice requirement mapping. GSMA(Global System for Mobile
378 Communications Association) defines the [GST] to indicate the network
379 slice requirement from the view of service provider.
380 [I-D.contreras-teas-slice-nbi] analysis the parameters of GST and
381 categorize the parameters into three classes, including the
382 attributes with direct impact on the transport network slice
383 definition. It is a good start for selecting the transport network
384 relevant parameters in order to define Network Slice Profile for
385 Transport Network. Network slice requirement parameters are also
386 necessary for the definition of transport network northbound
387 interface.
389 Inside the TN NSSMF, it is supposed to maintain the attributes of the
390 transport network slice. If the attributes of an existing TN NSSI
391 could satisfy the requirement from TN Network Slice Profile, the
392 existing TN NSSI could be selected and the mapping is finished If
393 there is no existing TN NSSI which could satisfy the requirement, a
394 new TN NSSI is supposed to be created by the NSSMF with new
395 attributes.
397 TN NSSI resource reservation should be considered to avoid over
398 allocation from multiple requests from NSMF (but the detailed
399 mechanism should be out of scope in the draft)
401 TN NSSMF sends the selected or newly allocated TN NSSI identifier to
402 NSMF. The mapping relationship between NSI identifier and TN NSSI
403 identifier is maintained in both NSMF and TN NSSMF.
405 YANG data model for the Transport Slice NBI, which could be used by a
406 higher level system which is the Transport slice consumer of a
407 Transport Slice Controller (TSC) to request, configure, and manage
408 the components of a transport slices, is defined in
409 [I-D.wd-teas-transport-slice-yang].
411 4.2. Network Slice Mapping in Control Plane
413 There is no explicit interaction between transport network and AN/CN
414 in the control plane, but the S-NSSAI defined in [TS23501] is treated
415 as the end-to-end network slice identifier in the control plane of AN
416 and CN, which is used in UE registration and PDU session setup. In
417 this draft, we assume that there is mapping relationship between
418 S-NSSAI and NSI in the management plane, thus it could be mapped to a
419 transport network slice .
421 Editor's note: The mapping relationship between NSI defined in
422 [TS23501] and S-NSSAI defined in [TS23501] is still in discussion.
424 4.3. Network Slice Mapping in data plane
426 If multiple network slices are carried through one physical interface
427 between AN/CN and TN, transport network slice interworking
428 identifier(TNSII) in the data plane needs to be introduced. If
429 different network slices are transported through different physical
430 interfaces, Network Slices could be distinguished by the interface
431 directly. Thus TNSII is not the only option for network slice
432 mapping, while it may help in introducing new network slices.
434 4.3.1. Data Plane Mapping Considerations
436 The mapping relationship between AN or CN network slice identifier
437 (either S-NSSAI in control plane or NSI/NSSI in management plane) and
438 TNSII needs to be maintained in AN/CN network nodes, and the mapping
439 relationship between TNSII and TNSI is maintained in the edge node of
440 transport network. When the packet of a uplink flow goes from AN to
441 TN, the packet is encapsulated based on the TNSII; then the
442 encapsulation of TNSII is read by the edge node of transport network,
443 which maps the packet to the corresponding transport network slice.
445 Editor's Note: We have considered to add "Network Instance" defined
446 in [TS23501]in the draft. However, after the discussion with 3GPP
447 people, we think the concept of "network instance" is a 'neither
448 Necessary nor Sufficient Condition' for network slice. Network
449 Instance could be determined by S-NSSAI, it could also depends on
450 other information; Network slice could also be allocated without
451 network instance (in my understanding) And, TNSII is not a
452 competitive concept with network instance.TNSII is a concept for the
453 data plane interconnection with transport network, network instance
454 may be used by AN and CN nodes to associate a network slice with
455 TNSII
457 4.3.2. Data Plane Mapping Design
459 The following picture shows the end-to-end network slice in data
460 plane:
462 +--+ +-----+ +----------------+
463 |UE|- - - -|(R)AN|---------------------------| UPF |
464 +--+ +-----+ +----------------+
465 |<----AN NS---->|<----------TN NS---------->|<----CN NS----->|
467 The mapping between 3GPP slice and transport slice in user plane
468 could happens in:
470 (R)AN: User data goes from (radio) access network to transport
471 network
473 UPF: User data goes from core network functions to transport network
475 Editor's Note: As figure 4.7.1. in [TS28530] describes, TN NS will
476 not only exist between AN and CN but may also within AN NS and CN NS.
477 However, here we just show the TN between AN and CN as an example to
478 avoid unncessary complexity.
480 The following picture shows the user plane protocol stack in end-to-
481 end 5G system.
483 +-----------+ | | |
484 |Application+--------------------|------------------|---------------|
485 +-----------+ | | +-----------+ |
486 | PDU Layer +--------------------|------------------|-| PDU Layer | |
487 +-----------+ +-------------+ | +-------------+ | +-----------+ |
488 | | | ___Relay___ |--|--| ___Relay___ |-|-| | |
489 | | | \/ GTP-U|--|--|GTP-U\/ GTP-U|-|-| GTP-U | |
490 | 5G-AN | |5G-AN +------+ | +------+------+ | +-----------+ |
491 | Protocol | |Protoc|UDP/IP|--|--|UDP/IP|UDP/IP|-|-| UDP/IP | |
492 | Layers | |Layers+------+ | +------+------+ | +-----------+ |
493 | | | | L2 |--|--| L2 | L2 |-|-| L2 | |
494 | | | +------+ | +------+------+ | +-----------+ |
495 | | | | L1 |--|--| L1 | L1 |-|-| L1 | |
496 +-----------+ +-------------+ | +-------------+ | +-----------+ |
497 UE 5G-AN | UPF | UPF |
498 N3 N9 N6
500 The following figure shows the typical encapsulation in N3 interface
501 which could be used to carry the transport network slice interworking
502 identifier (TNSII) between AN/CN and TN.
504 +------------------------+
505 | Application Protocols |
506 +------------------------+
507 | IP (User) |
508 +------------------------+
509 | GTP |
510 +------------------------+
511 | UDP |
512 +------------------------+
513 | IP |
514 +------------------------+
515 | Ethernet |
516 +------------------------+
518 4.3.2.1. Layer 3 and Layer 2 Encapsulations
520 If the encapsulation above IP layer is not visible to Transport
521 Network, it is not able to be used for network slice interworking
522 with transport network. In this case, IP header and Ethernet header
523 could be considered to provide information of network slice
524 interworking from AN or CN to TN.
526 +------------------------+-----------
527 | Application Protocols | ^
528 +------------------------+ |
529 | IP (User) | Invisible
530 +------------------------+ for
531 | GTP | TN
532 +------------------------+ |
533 | UDP | V
534 +------------------------+------------
535 | IP |
536 +------------------------+
537 | Ethernet |
538 +------------------------+
540 The following field in IP header and Ethernet header could be
541 considered :
543 IP Header:
545 o DSCP: It is traditionally used for the mapping of QoS identifier
546 between AN/CN and TN network. Although some values (e.g. The
547 unassigned code points) may be borrowed for the network slice
548 interworking, it may cause confusion between QoS mapping and
549 network slicing mapping.;
551 o Destination Address: It is possible to allocate different IP
552 addresses for entities in different network slice, then the
553 destination IP address could be used as the network slice
554 interworking identifier. However, it brings additional
555 requirement to IP address planning. In addition, in some cases
556 some AN or CN network slices may use duplicated IP addresses.
558 o Option fields/headers: It requires that both AN and CN nodes can
559 support the encapsulation and decapsulation of the options.
561 Ethernet header
563 o VLAN ID: It is widely used for the interconnection between AN/CN
564 nodes and the edge nodes of transport network for the access to
565 different VPNs. One possible problem is that the number of VLAN
566 ID can be supported by AN nodes is typically limited, which
567 effects the number of transport network slices a AN node can
568 attach to. Another problem is the total amount of VLAN ID (4K)
569 may not provide a comparable space as the network slice
570 identifiers of mobile networks.
572 Two or more options described above may also be used together as the
573 TNSII, while it would make the mapping relationship more complex to
574 maintain.
576 In some other case, when AN or CN could support more layer 3
577 encapsulations, more options are available as follows:
579 If the AN or CN could support MPLS, the protocol stack could be as
580 follows:
582 +------------------------+-----------
583 | Application Protocols | ^
584 +------------------------+ |
585 | IP (User) | Invisible
586 +------------------------+ for
587 | GTP | TN
588 +------------------------+ |
589 | UDP | V
590 +------------------------+------------
591 | MPLS |
592 +------------------------+
593 | IP |
594 +------------------------+
595 | Ethernet |
596 +------------------------+
598 A specified MPLS label could be used to as a TNSII.
600 If the AN or CN could support SRv6, the protocol stack is as follows:
602 +------------------------+-----------
603 | Application Protocols | ^
604 +------------------------+ |
605 | IP (User) | Invisible
606 +------------------------+ for
607 | GTP | TN
608 +------------------------+ |
609 | UDP | V
610 +------------------------+------------
611 | SRH |
612 +------------------------+
613 | IPv6 |
614 +------------------------+
615 | Ethernet |
616 +------------------------+
618 The following field could be considered to identify a network slice:
620 SRH:
622 o SRv6 functions: AN/CN is supposed to support the new function
623 extension of SRv6.
625 o Optional TLV: AN/CN is supposed to support the extension of
626 optional TLV of SRH.
628 4.3.2.2. Above Layer 3 Encapsulations
630 If the encapsulation above IP layer is visible to Transport Network,
631 it is able to be used to identify a network slice. In this case, UPD
632 and GTP-U could be considered to provide information of network slice
633 interworking between AN or CN and TN.
635 +------------------------+----------
636 | Application Protocols | |
637 +------------------------+ Invisible
638 | IP (User) | for
639 +------------------------+ TN
640 | GTP | |
641 +------------------------+------------
642 | UDP |
643 +------------------------+
644 | IP |
645 +------------------------+
646 | Ethernet |
647 +------------------------+
649 The following field in UDP header could be considered:
651 UDP Header:
653 o UDP Source port: The UDP source port is sometimes used for load
654 balancing. Using it for network slice mapping would require to
655 disable the load-balancing behavior.
657 5. Network Slice Mapping Summary
659 The following picture shows the mapping relationship between the
660 network slice identifier in management plane, control plane and user
661 plane.
663 AN/CN | TN
664 Management +---------+ | +---------+
665 Plane | NSI |<--------|------->| TN NSSI |
666 +---------+ | +---------+
667 | | |
668 | | |
669 Control +-----V-----+ | +----------+----------+
670 Plane | S-NSSAI | | | |
671 +-----------+ | | |
672 | +----V----+ +----V----+
673 +----------->| TNSII |<--------->| TNSI |
674 User | /Port |<--------->| |
675 Plane +---------+ +---------+
676 |
678 6. IANA Considerations
680 TBD
682 Note to RFC Editor: this section may be removed on publication as an
683 RFC.
685 7. Security Considerations
687 TBD
689 8. Acknowledgements
691 The authors would like to thank Shunsuke Homma for reviewing the
692 draft and giving valuable comments.
694 9. Normative References
696 [GST] "Generic Network Slice Template",
697 .
700 [I-D.contreras-teas-slice-nbi]
701 Contreras, L., Homma, S., and J. Ordonez-Lucena,
702 "Considerations for defining a Transport Slice NBI",
703 draft-contreras-teas-slice-nbi-01 (work in progress),
704 March 2020.
706 [I-D.wd-teas-transport-slice-yang]
707 Bo, W., Dhody, D., Han, L., and R. Rokui, "A Yang Data
708 Model for Transport Slice NBI", draft-wd-teas-transport-
709 slice-yang-02 (work in progress), July 2020.
711 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
712 Requirement Levels", BCP 14, RFC 2119,
713 DOI 10.17487/RFC2119, March 1997,
714 .
716 [TS23501] "3GPP TS23.501",
717 .
720 [TS28530] "3GPP TS28.530",
721 .
724 [TS28531] "3GPP TS28.531",
725 .
728 [TS28541] "3GPP TS 28.541",
729 .
732 [ZSM003] "ETSI ZSM003",
733 .
736 Authors' Addresses
738 Xuesong Geng
739 Huawei Technologies
741 Email: gengxuesong@huawei.com
743 Jie Dong
744 Huawei Technologies
746 Email: jie.dong@huawei.com
747 Ran Pang
748 China Unicom
750 Email: pangran@chinaunicom.cn
752 Liuyan Han
753 China Mobile
755 Email: hanliuyan@chinamobile.com
757 Tomonobu Niwa
758 KDDI
760 Email: to-niwa@kddi.com
762 Jaehwan Jin
763 LG U+
765 Email: daenamu1@lguplus.co.kr
767 Chang Liu
768 China Unicom
770 Email: liuc131@chinaunicom.cn
772 Nikesh Nageshar
773 Individual
775 Email: nikesh.nageshar@gmail.com