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Versions: 00 01 02

Network Working Group                                            X. Geng
Internet-Draft                                                   J. Dong
Intended status: Informational                       Huawei Technologies
Expires: January 14, 2021                                        R. Pang
                                                            China Unicom
                                                                  L. Han
                                                            China Mobile
                                                                T.  Niwa
                                                                    KDDI
                                                                  J. Jin
                                                                   LG U+
                                                                  C. Liu
                                                            China Unicom
                                                             N. Nageshar
                                                              Individual
                                                           July 13, 2020


 5G End-to-end Network Slice Mapping from the view of Transport Network
                draft-geng-teas-network-slice-mapping-02

Abstract

   Network Slicing is one of the core featrures in 5G.  End-to-end
   network slice consists of 3 major types of network segments: Access
   Network (AN), Mobile Core Network (CN) and Transport Network (TN).
   This draft describes the procedure of mapping relationship between 5G
   end-to-end network slice and transport network slice defined in IETF.
   This draft also intends to expose some gaps in the existing network
   management plane and data plane to support inter-domain network slice
   mapping.  Further work may require cooperation between IETF and 3GPP
   (or other standard organizations).  The definition of data model,
   signaling protocol extension and new encapsulation are out of the
   scope of this draft.

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute



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   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on January 14, 2021.

Copyright Notice

   Copyright (c) 2020 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Terminologies . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Network Slice Mapping Structure . . . . . . . . . . . . . . .   4
     3.1.  Requirements Profile  . . . . . . . . . . . . . . . . . .   5
     3.2.  Identifiers . . . . . . . . . . . . . . . . . . . . . . .   6
     3.3.  Relevant functions  . . . . . . . . . . . . . . . . . . .   6
   4.  Network Slice Mapping Procedure . . . . . . . . . . . . . . .   7
     4.1.  Network Slice Mapping in Management Plane . . . . . . . .   8
     4.2.  Network Slice Mapping in Control Plane  . . . . . . . . .   9
     4.3.  Network Slice Mapping in data plane . . . . . . . . . . .  10
       4.3.1.  Data Plane Mapping Considerations . . . . . . . . . .  10
       4.3.2.  Data Plane Mapping Design . . . . . . . . . . . . . .  10
   5.  Network Slice Mapping Summary . . . . . . . . . . . . . . . .  15
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  15
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  15
   8.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  15
   9.  Normative References  . . . . . . . . . . . . . . . . . . . .  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  16






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1.  Introduction

   Driven by the new applications of 5G, the concept of network slicing
   is defined to provide a logical network with specific capabilities
   and characteristics.  Network slice contains a set of network
   functions and allocated resources(e.g.  Computation, storage and
   network resources).  According to [TS28530], a 5G end-to-end network
   slice is composed of three major types network segments: Radio Access
   Network (RAN), Transport Network (TN) and Mobile Core Network (CN).
   Transport network is supposed to provide the required connectivity
   between AN and CN, which specific performance commitment.  For each
   end-to-end network slice, the topology and performance requirement
   for transport network can be very different, which requires transport
   network to have the capability of supporting multiple different
   transport network slices.

   A transport network slice is a virtual (logical) network with a
   particular network topology and a set of shared or dedicated network
   resources, which are used to provide the network slice consumer with
   the required connectivity, appropriate isolation and specific Service
   Level Agreement (SLA).  A transport network slice could span multiple
   technology (IP, Optical) and multiple administrative domains.
   Depending on the consumer's requirement, a transport network slice
   could be isolated from other concurrent transport network slices, in
   terms of data plane, control plane and management plane.  Transport
   network slice is being defined and discussed in IETF.

   Editor's Note: The work of

   The procedure of end-to-end network slice instance creation, network
   slice subnet instance creation and network slice instance termination
   in management plane are defined in [TS28531].  The end-to-end network
   slice allocation is defined in ETSI [ZSM003].  But there is no
   specifications about how to map end-to-end network slice in 5G system
   to transport network slice.  This draft describes the procedure of
   mapping 5G end-to-end network slice into transport network slice in
   management plane, control plane and user plane.

2.  Terminologies

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

   The following terms are used in this document:

   NS: Network Slice




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   NSI: Network Slice Instance

   NSSI: Network Slice Subnet Instance

   NSSAI: Network Slice Selection Assistance Information

   S-NSSAI: Single Network Slice Selection Assistance Information

   AN: Access Network

   RAN: Radio Access Network

   TN: Transport Network

   CN: Mobile Core Network

   DSCP: Differentiated Services Code Point

   CSMF: Communication Service Management Function

   NSMF: Network Slice Management Function

   NSSMF: Network Slice Subnet Management Function

   GST: General Slice Template

   TNSII: Transport Network Slice Interworking Identifier

   TNSI: Transport Network Slice Identifier

   PDU: Protocol Data Unit

   Editor's Note: Terminologies defined in 3GPP, e.g.,Network Slice
   Subnet Management Function(NSSMF), Network Slice Subnet
   Instance(NSSI) and Network Slice Selection Assistance
   Information(NSSAI), is used in the end-to-end network slice mapping,
   which may not be used necessarily within the transport network.

3.  Network Slice Mapping Structure

   The following figure shows the necessary elements for mapping end-to-
   end network slice into transport network slice.  All these network
   slice elements are classified into three groups: requirements/
   capabilities, identifiers and relevant functions.







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                   +-----------------+
                   |       CSMF      |
                   +--------+--------+
                            |
                   +--------V--------+
                   |       NSMF      |
                   +-----------------+
        +----------|  NSI Identifier |----------+
        |          | Service Profile |          |
        |          |  TN  Network-   |          |
        |          | -Slice Profile  |          |
        |          +-----------------+          |
        |                   |                   |
 +------V------+ +----------V----------+ +------V------+
 |  AN NSSMF   | |      TN NSSMF       | |   CN NSSMF  |
 +-------------+ +---------------------+ +-------------+
 |   AN-NSSI-  | |  TN-NSSI Identifier | |   CN-NSSI-  |
 | -Identifier | |  Function Management| | -Identifier |
 |     ...     | |         ...         | |     ...     |    Management
 +-------------+ +---------------------+ +-------------+      Plane
      |           |                   |           |      -----------------
      |<----------PDU session (S-NSSAI)---------->|           Control
      |           |                   |           |            Plane
      V           V                   V           V      -----------------
      /\       +-----+             +-----+    +-------+        Data
     /AN\ -----|  PE |-----...-----| PE  |----|  UPF  |        Plane
    /____\     +-----+             +-----+    +-------+
      |-->TNSII<--|------>TNSI<-------|-->TNSII<--|


3.1.  Requirements Profile

   In order to satisfy a tenant's request for a network slice with
   certain characteristics, creating a new network slice or using
   existing network slice instance is constrained by the customer's
   requirement and the capability of the network slices.

   o  Service Profile: represents the properties of network slice
      related requirement that should be supported by the network slice
      instance in 5G network.  Service profile is defined in [TS28541]
      6.3.3.

   o  TN Network Slice Profile: represents the properties of transport
      network slice related requirement that should be supported by the
      transport network slice in a 5G network.  Slice Profile is defined
      in [TS28541] 6.3.4.  TN Network slice profile is newly defined in
      this draft.




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3.2.  Identifiers

   Network slice related identifiers in management plane, control plane
   and user(data) plane play an important role in end-to-end network
   slice mapping.

   o  Single Network Slice Selection Assistance Information(S-NSSAI):
      end-to-end network slice identifier in control plane, which is
      defined in [TS23501];

   o  Network Slice Instance(NSI) Identifier:end-to-end network slice
      identifier in management plane, which is created in NSMF; NSI is
      is set of Network Function instances and the required resources
      (e.g. compute, storage and networking resources) which form a
      deployed Network Slice, which is defined in [TS23501]; ;

   o  Transport Network Slice Instance(TN-NSSI) Identifier: transport
      network slice identifier in management plane, which is created in
      TN NSSMF; TN-NSSI is newly defined in this draft.

   o  Transport Network Slice Interworking Identifier (TNSII): network
      slice identifier which is used for mapping end-to-end network
      slice into transport network slice in user plane.  TNSII is newly
      defined in this draft.

   o  Transport Network Slice Identifier(TNSI): transport network slice
      identifier in data plane(user plane).  TNSI is newly defined in
      this draft.

   The relationship between these identifiers are specifies in the
   following sections.

3.3.  Relevant functions

   There are a set of slice relevant functions that are necessary for
   transport network slice management:

   o  Topology management

   o  QoS management

   o  Resource management

   o  Measurement management

   o  ...





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   Some of these functions are implemented inside the transport network
   and independent from the end-to-end network slice, e.g., topology
   management, QoS management, resource management; Some of the
   functions are related to the end-to-end network slice and should
   cooperate with other network elements from other domain, e.g.,
   Measurement management.

4.  Network Slice Mapping Procedure

   This section provides a general procedure of network slice mapping:

           +--------------------------------+
           |       Requirement Matching     |
           +---------------+----------------+
                           |
                           V
           +--------------------------------+
           |       NSI<->TN NSSI  Mapping   |
           +---------------+----------------+
                           |
                           V
           +--------------------------------+
           |       S-NSSAI Selection        |
           +---------------+----------------+
                           |
                           V
           +--------------------------------+
           |S-NSSAI<---------->TNSII Mapping|
           |      (NSI<->TN NSSI)           |
           +---------------+----------------+
                           |
                           V
           +--------------------------------+
           |       TNSII<->TNSI  Mapping    |
           +--------------------------------+

   1.  NSMF receives the request from CSMF for allocation of a network
   slice instance with certain characteristics.

   2.  Based on the service requirement , NSMF acquires requirements for
   the end-to-end network slice instance , which is defined in Service
   Profile([TS28541] section 6.3.3).

   3.  NSMF derives transport network slice related requirements from
   the Service profile, and maintains them in Transport Network Slice
   Profile, So as to CN Slice Profile and AN Slice Profile, in order to
   decide on the constituent NSSIs(including AN NSSI, CN NSSI and TN




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   NSSI) of the NSI, based on the service profile and the endpoint
   information(AN/CN edge nodes).

   4.  NSMF sends the Transport Network Slice Profile, endpoint
   information, along with other TS NBI attributes to TN NSSMF for TN
   NSSI allocation.

   5.  TN NSSMF allocates TN NSSI which could satisfy the requirement of
   Transport Network Slice Profile between the specified endpoints (AN/
   CN edge nodes) and sends the TN NSSI Identifier to NSMF.

   6.  NSMF acquires the mapping relationship between NSI and TN NSSI.

   7.  NSMF matains the mapping relationship between NSI and S-NSSAI and
   the mapping relationship between TN NSSI and TNSII, which could be
   used to set up mapping relationship between S-NSSAI and TNSII.

   8.  When a PDU session is set up between AN and CN, an S-NSSAI is
   slected for the PDU session.

   9.  AN/CN edge nodes encapsulate the packet using TNSII, according to
   the selected S-NSSAI.  Network Slice could also be differentiated by
   physical interface, if different network slices are transported
   through different interface;

   10.  The edge node of transport network parses the TNSII from the
   packet and maps the packet to the corresponding transport network
   slice.  It may encapsulate packet with TNSI.  The nodes in transport
   network transit the packet inside the corresponding transport network
   slice according to TNSI.

   The procedure of end-to-end network slice mapping involves the
   mapping in three network planes: management plane, control plane and
   data plane.

4.1.  Network Slice Mapping in Management Plane

   The transport network management Plane maintains the interface
   between NSMF and TN NSSMF, which 1) guarantees that transport network
   slice could connect the AN and CN with specified characteristics that
   satisfy the requirements of communication; 2) builds up the mapping
   relationship between NSI identifier and TN NSSI identifier; 3)
   maintains the end-to-end slice relevant functions;

   Service Profile defined in[TS28541] represents the requirement of
   end-to-end network slice instance in 5G network.  Parameters defined
   in Service Profile include Latency, resource sharing level,
   availability and so on.  How to decompose the end-to-end requirement



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   to the transport network requirement is one of the key issues in
   Network slice requirement mapping.  GSMA(Global System for Mobile
   Communications Association) defines the [GST] to indicate the network
   slice requirement from the view of service provider.
   [I-D.contreras-teas-slice-nbi] analysis the parameters of GST and
   categorize the parameters into three classes, including the
   attributes with direct impact on the transport network slice
   definition.  It is a good start for selecting the transport network
   relevant parameters in order to define Network Slice Profile for
   Transport Network.  Network slice requirement parameters are also
   necessary for the definition of transport network northbound
   interface.

   Inside the TN NSSMF, it is supposed to maintain the attributes of the
   transport network slice.  If the attributes of an existing TN NSSI
   could satisfy the requirement from TN Network Slice Profile, the
   existing TN NSSI could be selected and the mapping is finished If
   there is no existing TN NSSI which could satisfy the requirement, a
   new TN NSSI is supposed to be created by the NSSMF with new
   attributes.

   TN NSSI resource reservation should be considered to avoid over
   allocation from multiple requests from NSMF (but the detailed
   mechanism should be out of scope in the draft)

   TN NSSMF sends the selected or newly allocated TN NSSI identifier to
   NSMF.  The mapping relationship between NSI identifier and TN NSSI
   identifier is maintained in both NSMF and TN NSSMF.

   YANG data model for the Transport Slice NBI, which could be used by a
   higher level system which is the Transport slice consumer of a
   Transport Slice Controller (TSC) to request, configure, and manage
   the components of a transport slices, is defined in
   [I-D.wd-teas-transport-slice-yang].

4.2.  Network Slice Mapping in Control Plane

   There is no explicit interaction between transport network and AN/CN
   in the control plane, but the S-NSSAI defined in [TS23501] is treated
   as the end-to-end network slice identifier in the control plane of AN
   and CN, which is used in UE registration and PDU session setup.  In
   this draft, we assume that there is mapping relationship between
   S-NSSAI and NSI in the management plane, thus it could be mapped to a
   transport network slice .

   Editor's note: The mapping relationship between NSI defined in
   [TS23501] and S-NSSAI defined in [TS23501] is still in discussion.




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4.3.  Network Slice Mapping in data plane

   If multiple network slices are carried through one physical interface
   between AN/CN and TN, transport network slice interworking
   identifier(TNSII) in the data plane needs to be introduced.  If
   different network slices are transported through different physical
   interfaces, Network Slices could be distinguished by the interface
   directly.  Thus TNSII is not the only option for network slice
   mapping, while it may help in introducing new network slices.

4.3.1.  Data Plane Mapping Considerations

   The mapping relationship between AN or CN network slice identifier
   (either S-NSSAI in control plane or NSI/NSSI in management plane) and
   TNSII needs to be maintained in AN/CN network nodes, and the mapping
   relationship between TNSII and TNSI is maintained in the edge node of
   transport network.  When the packet of a uplink flow goes from AN to
   TN, the packet is encapsulated based on the TNSII; then the
   encapsulation of TNSII is read by the edge node of transport network,
   which maps the packet to the corresponding transport network slice.

   Editor's Note: We have considered to add "Network Instance" defined
   in [TS23501]in the draft.  However, after the discussion with 3GPP
   people, we think the concept of "network instance" is a 'neither
   Necessary nor Sufficient Condition' for network slice.  Network
   Instance could be determined by S-NSSAI, it could also depends on
   other information; Network slice could also be allocated without
   network instance (in my understanding) And, TNSII is not a
   competitive concept with network instance.TNSII is a concept for the
   data plane interconnection with transport network, network instance
   may be used by AN and CN nodes to associate a network slice with
   TNSII

4.3.2.  Data Plane Mapping Design

   The following picture shows the end-to-end network slice in data
   plane:

   +--+       +-----+                           +----------------+
   |UE|- - - -|(R)AN|---------------------------|       UPF      |
   +--+       +-----+                           +----------------+
    |<----AN NS---->|<----------TN NS---------->|<----CN NS----->|


   The mapping between 3GPP slice and transport slice in user plane
   could happens in:





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   (R)AN: User data goes from (radio) access network to transport
   network

   UPF: User data goes from core network functions to transport network

   Editor's Note: As figure 4.7.1. in [TS28530] describes, TN NS will
   not only exist between AN and CN but may also within AN NS and CN NS.
   However, here we just show the TN between AN and CN as an example to
   avoid unncessary complexity.

   The following picture shows the user plane protocol stack in end-to-
   end 5G system.

  +-----------+                    |                  |               |
  |Application+--------------------|------------------|---------------|
  +-----------+                    |                  | +-----------+ |
  | PDU Layer +--------------------|------------------|-| PDU Layer | |
  +-----------+   +-------------+  |  +-------------+ | +-----------+ |
  |           |   | ___Relay___ |--|--| ___Relay___ |-|-|           | |
  |           |   |     \/ GTP-U|--|--|GTP-U\/ GTP-U|-|-|   GTP-U   | |
  |   5G-AN   |   |5G-AN +------+  |  +------+------+ | +-----------+ |
  |  Protocol |   |Protoc|UDP/IP|--|--|UDP/IP|UDP/IP|-|-|   UDP/IP  | |
  |   Layers  |   |Layers+------+  |  +------+------+ | +-----------+ |
  |           |   |      |  L2  |--|--|  L2  |  L2  |-|-|     L2    | |
  |           |   |      +------+  |  +------+------+ | +-----------+ |
  |           |   |      |  L1  |--|--|  L1  |  L1  |-|-|     L1    | |
  +-----------+   +-------------+  |  +-------------+ | +-----------+ |
       UE              5G-AN       |        UPF       |      UPF      |
                                   N3                 N9              N6

   The following figure shows the typical encapsulation in N3 interface
   which could be used to carry the transport network slice interworking
   identifier (TNSII) between AN/CN and TN.

   +------------------------+
   | Application Protocols  |
   +------------------------+
   |       IP (User)        |
   +------------------------+
   |          GTP           |
   +------------------------+
   |          UDP           |
   +------------------------+
   |          IP            |
   +------------------------+
   |       Ethernet         |
   +------------------------+




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4.3.2.1.  Layer 3 and Layer 2 Encapsulations

   If the encapsulation above IP layer is not visible to Transport
   Network, it is not able to be used for network slice interworking
   with transport network.  In this case, IP header and Ethernet header
   could be considered to provide information of network slice
   interworking from AN or CN to TN.

   +------------------------+-----------
   | Application Protocols  |      ^
   +------------------------+      |
   |       IP (User)        |  Invisible
   +------------------------+     for
   |          GTP           |     TN
   +------------------------+      |
   |          UDP           |      V
   +------------------------+------------
   |          IP            |
   +------------------------+
   |       Ethernet         |
   +------------------------+

   The following field in IP header and Ethernet header could be
   considered :

   IP Header:

   o  DSCP: It is traditionally used for the mapping of QoS identifier
      between AN/CN and TN network.  Although some values (e.g.  The
      unassigned code points) may be borrowed for the network slice
      interworking, it may cause confusion between QoS mapping and
      network slicing mapping.;

   o  Destination Address: It is possible to allocate different IP
      addresses for entities in different network slice, then the
      destination IP address could be used as the network slice
      interworking identifier.  However, it brings additional
      requirement to IP address planning.  In addition, in some cases
      some AN or CN network slices may use duplicated IP addresses.

   o  Option fields/headers: It requires that both AN and CN nodes can
      support the encapsulation and decapsulation of the options.

   Ethernet header

   o  VLAN ID: It is widely used for the interconnection between AN/CN
      nodes and the edge nodes of transport network for the access to
      different VPNs.  One possible problem is that the number of VLAN



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      ID can be supported by AN nodes is typically limited, which
      effects the number of transport network slices a AN node can
      attach to.  Another problem is the total amount of VLAN ID (4K)
      may not provide a comparable space as the network slice
      identifiers of mobile networks.

   Two or more options described above may also be used together as the
   TNSII, while it would make the mapping relationship more complex to
   maintain.

   In some other case, when AN or CN could support more layer 3
   encapsulations, more options are available as follows:

   If the AN or CN could support MPLS, the protocol stack could be as
   follows:

   +------------------------+-----------
   | Application Protocols  |      ^
   +------------------------+      |
   |       IP (User)        |  Invisible
   +------------------------+     for
   |          GTP           |     TN
   +------------------------+      |
   |          UDP           |      V
   +------------------------+------------
   |         MPLS           |
   +------------------------+
   |          IP            |
   +------------------------+
   |       Ethernet         |
   +------------------------+

   A specified MPLS label could be used to as a TNSII.

   If the AN or CN could support SRv6, the protocol stack is as follows:
















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   +------------------------+-----------
   | Application Protocols  |      ^
   +------------------------+      |
   |       IP (User)        |  Invisible
   +------------------------+     for
   |          GTP           |     TN
   +------------------------+      |
   |          UDP           |      V
   +------------------------+------------
   |          SRH           |
   +------------------------+
   |         IPv6           |
   +------------------------+
   |       Ethernet         |
   +------------------------+

   The following field could be considered to identify a network slice:

   SRH:

   o  SRv6 functions: AN/CN is supposed to support the new function
      extension of SRv6.

   o  Optional TLV: AN/CN is supposed to support the extension of
      optional TLV of SRH.

4.3.2.2.  Above Layer 3 Encapsulations

   If the encapsulation above IP layer is visible to Transport Network,
   it is able to be used to identify a network slice.  In this case, UPD
   and GTP-U could be considered to provide information of network slice
   interworking between AN or CN and TN.

   +------------------------+----------
   | Application Protocols  |     |
   +------------------------+ Invisible
   |       IP (User)        |     for
   +------------------------+     TN
   |          GTP           |     |
   +------------------------+------------
   |          UDP           |
   +------------------------+
   |          IP            |
   +------------------------+
   |       Ethernet         |
   +------------------------+

   The following field in UDP header could be considered:



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   UDP Header:

   o  UDP Source port: The UDP source port is sometimes used for load
      balancing.  Using it for network slice mapping would require to
      disable the load-balancing behavior.

5.  Network Slice Mapping Summary

   The following picture shows the mapping relationship between the
   network slice identifier in management plane, control plane and user
   plane.

                 AN/CN            |              TN
   Management +---------+         |        +---------+
     Plane    |   NSI   |<--------|------->| TN NSSI |
              +---------+         |        +---------+
                   |              |             |
                   |              |             |
    Control  +-----V-----+        |  +----------+----------+
     Plane   |  S-NSSAI  |        |  |                     |
             +-----------+        |  |                     |
                   |            +----V----+           +----V----+
                   +----------->|  TNSII  |<--------->|   TNSI  |
     User                       |  /Port  |<--------->|         |
     Plane                      +---------+           +---------+
                                  |

6.  IANA Considerations

   TBD

   Note to RFC Editor: this section may be removed on publication as an
   RFC.

7.  Security Considerations

   TBD

8.  Acknowledgements

   The authors would like to thank Shunsuke Homma for reviewing the
   draft and giving valuable comments.

9.  Normative References

   [GST]      "Generic Network Slice Template",
              <https://www.gsma.com/newsroom/all-documents/generic-
              network-slice-template-v2-0/>.



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   [I-D.contreras-teas-slice-nbi]
              Contreras, L., Homma, S., and J. Ordonez-Lucena,
              "Considerations for defining a Transport Slice NBI",
              draft-contreras-teas-slice-nbi-01 (work in progress),
              March 2020.

   [I-D.wd-teas-transport-slice-yang]
              Bo, W., Dhody, D., Han, L., and R. Rokui, "A Yang Data
              Model for Transport Slice NBI", draft-wd-teas-transport-
              slice-yang-02 (work in progress), July 2020.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [TS23501]  "3GPP TS23.501",
              <https://portal.3gpp.org/desktopmodules/Specifications/
              SpecificationDetails.aspx?specificationId=3144>.

   [TS28530]  "3GPP TS28.530",
              <https://portal.3gpp.org/desktopmodules/Specifications/
              SpecificationDetails.aspx?specificationId=3273>.

   [TS28531]  "3GPP TS28.531",
              <https://portal.3gpp.org/desktopmodules/Specifications/
              SpecificationDetails.aspx?specificationId=3274>.

   [TS28541]  "3GPP TS 28.541",
              <https://portal.3gpp.org/desktopmodules/Specifications/
              SpecificationDetails.aspx?specificationId=3400>.

   [ZSM003]   "ETSI ZSM003",
              <https://portal.3gpp.org/desktopmodules/Specifications/
              SpecificationDetails.aspx?specificationId=3144>.

Authors' Addresses

   Xuesong Geng
   Huawei Technologies

   Email: gengxuesong@huawei.com


   Jie Dong
   Huawei Technologies

   Email: jie.dong@huawei.com



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Internet-Draft  draft-geng-teas-network-slice-mapping-01       July 2020


   Ran Pang
   China Unicom

   Email: pangran@chinaunicom.cn


   Liuyan Han
   China Mobile

   Email: hanliuyan@chinamobile.com


   Tomonobu Niwa
   KDDI

   Email: to-niwa@kddi.com


   Jaehwan Jin
   LG U+

   Email: daenamu1@lguplus.co.kr


   Chang Liu
   China Unicom

   Email: liuc131@chinaunicom.cn


   Nikesh Nageshar
   Individual

   Email: nikesh.nageshar@gmail.com

















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