SCHC: Generic Framework for Static Context Header Compression and Fragmentation
RFC 8724
Document | Type | RFC - Proposed Standard (April 2020; No errata) | |
---|---|---|---|
Authors | Ana Minaburo , Laurent Toutain , Carles Gomez , Dominique Barthel , Juan-Carlos Zúñiga | ||
Last updated | 2020-04-15 | ||
Replaces | draft-toutain-lpwan-ipv6-static-context-hc | ||
Stream | Internet 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 | Pascal Thubert | ||
Shepherd write-up | Show (last changed 2019-10-09) | ||
IESG | IESG state | RFC 8724 (Proposed Standard) | |
Action Holders |
(None)
|
||
Consensus Boilerplate | Yes | ||
Telechat date | |||
Responsible AD | Suresh Krishnan | ||
Send notices to | Dominique Barthel <dominique.barthel@orange.com>, Pascal Thubert <pthubert@cisco.com> | ||
IANA | IANA review state | Version Changed - Review Needed | |
IANA action state | No IANA Actions |
Internet Engineering Task Force (IETF) A. Minaburo Request for Comments: 8724 Acklio Category: Standards Track L. Toutain ISSN: 2070-1721 IMT Atlantique C. Gomez Universitat Politecnica de Catalunya D. Barthel Orange Labs JC. Zuniga SIGFOX April 2020 SCHC: Generic Framework for Static Context Header Compression and Fragmentation Abstract This document defines the Static Context Header Compression and fragmentation (SCHC) framework, which provides both a header compression mechanism and an optional fragmentation mechanism. SCHC has been designed with Low-Power Wide Area Networks (LPWANs) in mind. SCHC compression is based on a common static context stored both in the LPWAN device and in the network infrastructure side. This document defines a generic header compression mechanism and its application to compress IPv6/UDP headers. This document also specifies an optional fragmentation and reassembly mechanism. It can be used to support the IPv6 MTU requirement over the LPWAN technologies. Fragmentation is needed for IPv6 datagrams that, after SCHC compression or when such compression was not possible, still exceed the Layer 2 maximum payload size. The SCHC header compression and fragmentation mechanisms are independent of the specific LPWAN technology over which they are used. This document defines generic functionalities and offers flexibility with regard to parameter settings and mechanism choices. This document standardizes the exchange over the LPWAN between two SCHC entities. Settings and choices specific to a technology or a product are expected to be grouped into profiles, which are specified in other documents. Data models for the context and profiles are out of scope. 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/rfc8724. 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 2. Requirements Notation 3. LPWAN Architecture 4. Terminology 5. SCHC Overview 5.1. SCHC Packet Format 5.2. Functional Mapping 6. RuleID 7. Compression/Decompression 7.1. SCHC C/D Rules 7.2. Packet Processing 7.3. Matching Operators 7.4. Compression/Decompression Actions (CDA) 7.4.1. Processing Fixed-Length Fields 7.4.2. Processing Variable-Length Fields 7.4.3. Not-Sent CDA 7.4.4. Value-Sent CDA 7.4.5. Mapping-Sent CDA 7.4.6. LSB CDA 7.4.7. DevIID, AppIID CDA 7.4.8. Compute-* 8. Fragmentation/Reassembly 8.1. Overview 8.2. SCHC F/R Protocol Elements 8.2.1. Messages 8.2.2. Tiles, Windows, Bitmaps, Timers, Counters 8.2.3. Integrity Checking 8.2.4. Header Fields 8.3. SCHC F/R Message Formats 8.3.1. SCHC Fragment Format 8.3.2. SCHC ACK Format 8.3.3. SCHC ACK REQ Format 8.3.4. SCHC Sender-Abort Format 8.3.5. SCHC Receiver-Abort Format 8.4. SCHC F/R Modes 8.4.1. No-ACK Mode 8.4.2. ACK-Always Mode 8.4.3. ACK-on-Error Mode 9. Padding Management 10. SCHC Compression for IPv6 and UDP Headers 10.1. IPv6 Version Field 10.2. IPv6 Traffic Class FieldShow full document text