



RTGWG                                                      Y. Zhang, Ed.
Internet-Draft                                             X. Zhang, Ed.
Intended status: Standards Track                            China Unicom
Expires: 27 December 2025                                   25 June 2025


    Application assistance based mobile network user-plane evolution
                   draft-zhang-app-assistance-upe-00

Abstract

   This document analyzes the problems and necessity for evolution of
   user-plane in mobile networks.  In addition, the use cases and
   requirements are discussed.

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   This Internet-Draft is submitted in full conformance with the
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   This Internet-Draft will expire on 27 December 2025.

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   provided without warranty as described in the Revised BSD License.






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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions and Definitions . . . . . . . . . . . . . . . . .   3
   3.  Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . .   3
     3.1.  High-value users guarantee  . . . . . . . . . . . . . . .   3
     3.2.  Security traceability . . . . . . . . . . . . . . . . . .   3
   4.  Requirement . . . . . . . . . . . . . . . . . . . . . . . . .   3
     4.1.  User plane path programmability . . . . . . . . . . . . .   4
     4.2.  Cross-Layer Interworking Capability . . . . . . . . . . .   4
   5.  Work flow . . . . . . . . . . . . . . . . . . . . . . . . . .   4
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .   4
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   4
   8.  Normative References  . . . . . . . . . . . . . . . . . . . .   4
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   4

1.  Introduction

   Driven by emerging applications such as autonomous driving and
   immersive communications, 6G system is moving toward full-scene
   intelligence with ultra-low latency, high reliability, and
   differentiated demand assurance.  However, the mobile core network
   and IP bearer network were developed independently.  There are
   information gaps in the forwarding of tunnels such as N3, N9, and N19
   between the base station and user plane, as well as between user
   plane functions.  Specifically, the mobile user plane lacks awareness
   of the IP bearer network status, while the IP bearer network does not
   perceive the differentiated service requirements of the mobile
   network.  This leads to some uncertainties in tunnel forwarding
   across IP bearer network (e.g., N3/N9/N19), which poses a key
   challenge to achieving fine-grained and differentiated service
   quality assurance in 6G.

   Therefore, as a critical network function bridging the mobile network
   and IP bearer network, the future 6G user plane should support cross-
   domain coordination with end-to-end application awareness and service
   assurance capabilities.  It is recommended that the design of the 6G
   user plane should considers information interaction with the IP
   bearer network based on application assistance, especially to
   establish the interaction of wireless bearer between AN-UPFs and the
   interaction of N9/N19 wide-area networks between user-plane nodes.










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2.  Conventions and Definitions

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.  Abbreviations and definitions used in this
   document:

   *IFIT: In-situ Flow Information Telemetry. 6G: The Sixth Generation
   Mobile Communication System QCI: QoS Class Identifier DSCP:
   Differentiated Services Code Point QoS: Quality of Service

3.  Use Cases

3.1.  High-value users guarantee

   High-value mobile subscribers, such as VIP users of ICP (Internet
   Content Providers), require enhanced quality assurance when
   initiating specific services.  However, these users can currently
   only be identified by the mobile core network.  The path selection
   for traffic forwarding over N3/N9/N19 interfaces relies primarily on
   coarse-grained mappings between QCI and DSCP.  The IP bearer network
   lacks real-time awareness of session-level information from the core
   network (e.g., QoS Flow Identifier, data flow priority), and can only
   allocate resources based on a fixed policy, with a high cross-domain
   path adjustment latency.

3.2.  Security traceability

   When network equipments or data center are maliciously attacked, a
   large volume of messages are generated and propagated within the
   network.  These messages take up substantial bandwidth resources
   during forwarding, interfering with or even blocking legitimate
   service flows, and severely degrading network performance and user
   experience.  Therefore, the coordinated security traceability across
   the mobile network and IP bearer network is required.  By interaction
   between mobile network and IP bearer network，it can locate the real
   initiator of abnormal traffic and block the traffic into the network
   port in time to protect users and network security.

4.  Requirement

   The 6G user-plane protocol stack needs to be optimized and
   reconfigured to support path programmability, bidirectional delivery
   of mobile and IP bearer network information, resulting in cross-
   domain collaboration capabilities for end-to-end intelligent sensing
   and intent delivery development.



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4.1.  User plane path programmability

   For IP packets outside the GTP-U tunnel, 6G UP supports modifying the
   IP packet header information and inserting the information to
   encapsulate the IP packet and pass it to the WAN, which can execute
   the relevant policies based on the IP packet header information.

4.2.  Cross-Layer Interworking Capability

   The 6G user plane is able to bring information such as application
   demand and application status into the IP bearer network based
   forwarding path.  Through the interaction of mobile network and IP
   bearer network, it forms the cross-layer collaboration capability of
   end-to-end service awareness and information delivery..

5.  Work flow

   TBD

6.  Security Considerations

   TBD

7.  IANA Considerations

   TBD

8.  Normative References

   [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>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

Authors' Addresses

   Yaomin Zhang (editor)
   China Unicom
   Beijing
   China
   Email: zhangym2533@chinaunicom.cn






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   Xuebei Zhang (editor)
   China Unicom
   Beijing
   China
   Email: zhangxb170@chinaunicom.cn














































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