Subscriber and Performance Policy Identifier Context Headers in the Network Service Header (NSH)
RFC 8979
Document | Type | RFC - Proposed Standard (February 2021; No errata) | |
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Authors | Behcet Sarikaya , Dirk Hugo , Mohamed Boucadair | ||
Last updated | 2021-02-05 | ||
Replaces | draft-sfc-serviceid-header | ||
Stream | Internent Engineering Task Force (IETF) | ||
Formats | plain text html xml pdf htmlized (tools) htmlized bibtex | ||
Reviews | |||
Stream | WG state | Submitted to IESG for Publication | |
Document shepherd | Greg Mirsky | ||
Shepherd write-up | Show (last changed 2020-05-17) | ||
IESG | IESG state | RFC 8979 (Proposed Standard) | |
Action Holders |
(None)
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Consensus Boilerplate | Yes | ||
Telechat date | |||
Responsible AD | Martin Vigoureux | ||
Send notices to | Greg Mirsky <gregimirsky@gmail.com> | ||
IANA | IANA review state | Version Changed - Review Needed | |
IANA action state | RFC-Ed-Ack |
Internet Engineering Task Force (IETF) B. Sarikaya Request for Comments: 8979 Category: Standards Track D. von Hugo ISSN: 2070-1721 Deutsche Telekom M. Boucadair Orange February 2021 Subscriber and Performance Policy Identifier Context Headers in the Network Service Header (NSH) Abstract This document defines the Subscriber and Performance Policy Identifier Context Headers. These Variable-Length Context Headers can be carried in the Network Service Header (NSH) and are used to inform Service Functions (SFs) of subscriber- and performance-related information for the sake of policy enforcement and appropriate Service Function Chaining (SFC) operations. The structure of each Context Header and their use and processing by NSH-aware nodes are described. Status of This Memo This is an Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at https://www.rfc-editor.org/info/rfc8979. Copyright Notice Copyright (c) 2021 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 2. Conventions and Terminology 3. Subscriber Identifier NSH Variable-Length Context Header 4. Performance Policy Identifier NSH Variable-Length Context Headers 5. MTU Considerations 6. IANA Considerations 7. Security Considerations 8. References 8.1. Normative References 8.2. Informative References Acknowledgements Authors' Addresses 1. Introduction This document discusses how to inform Service Functions (SFs) [RFC7665] about subscriber and service policy information when required for the sake of policy enforcement within a single administrative domain. In particular, subscriber-related information may be required to enforce subscriber-specific SFC-based traffic policies. However, the information carried in packets may not be sufficient to unambiguously identify a subscriber. This document fills this void by specifying a new Network Service Header (NSH) [RFC8300] Context Header to convey and disseminate such information within the boundaries of a single administrative domain. As discussed in Section 3, the use of obfuscated and non-persistent identifiers is recommended. Also, traffic steering by means of SFC may be driven, for example, by Quality of Service (QoS) considerations. Typically, QoS information may serve as an input for the computation, establishment, and selection of the Service Function Path (SFP). Furthermore, the dynamic structuring of Service Function Chains and their subsequent SFPs may be conditioned by QoS requirements that will affect the identification, location, and sequencing of SF instances. Hence, the need arises to provide downstream SFs with a performance policy identifier in order for them to appropriately meet the QoS requirements. This document also specifies a new NSH Context Header (Section 4) to convey such policy identifiers. The context information defined in this document can be applicable in the context of mobile networks (particularly in the 3GPP-defined (S)Gi interface) [CASE-MOBILITY]. Typically, because of the widespread use of private IPv4 addresses in those networks, if the SFs to be invoked are located after a NAT function, the identification based on the internal IPv4 address is not possible once the NAT has been crossed. NAT functionality can reside in a distinct node. For a 4G 3GPP network, that node can be the Packet Data Network (PDN) Gateway (PGW) as specified in [TS23401]. For a 5GShow full document text