Internet Engineering Task Force (IETF)                    M. Bishop, Ed.
Request for Comments: 9114                                        Akamai
Category: Standards Track                                      June 2022
ISSN: 2070-1721


                                 HTTP/3

Abstract

   The QUIC transport protocol has several features that are desirable
   in a transport for HTTP, such as stream multiplexing, per-stream flow
   control, and low-latency connection establishment.  This document
   describes a mapping of HTTP semantics over QUIC.  This document also
   identifies HTTP/2 features that are subsumed by QUIC and describes
   how HTTP/2 extensions can be ported to HTTP/3.

Status of This Memo

   This is an Internet Standards Track document.
   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/rfc9114.

Table of Contents

   1.  Introduction
     1.1.  Prior Versions of HTTP
     1.2.  Delegation to QUIC
   2.  HTTP/3 Protocol Overview
     2.1.  Document Organization
     2.2.  Conventions and Terminology
   3.  Connection Setup and Management
     3.1.  Discovering an HTTP/3 Endpoint
       3.1.1.  HTTP Alternative Services
       3.1.2.  Other Schemes
     3.2.  Connection Establishment
     3.3.  Connection Reuse
   4.  Expressing HTTP Semantics in HTTP/3
     4.1.  HTTP Message Framing
       4.1.1.  Request Cancellation and Rejection
       4.1.2.  Malformed Requests and Responses
     4.2.  HTTP Fields
       4.2.1.  Field Compression
       4.2.2.  Header Size Constraints
     4.3.  HTTP Control Data
       4.3.1.  Request Pseudo-Header Fields
       4.3.2.  Response Pseudo-Header Fields
     4.4.  The CONNECT Method
     4.5.  HTTP Upgrade
     4.6.  Server Push
   5.  Connection Closure
     5.1.  Idle Connections
     5.2.  Connection Shutdown
     5.3.  Immediate Application Closure
     5.4.  Transport Closure
   6.  Stream Mapping and Usage
     6.1.  Bidirectional Streams
     6.2.  Unidirectional Streams
       6.2.1.  Control Streams
       6.2.2.  Push Streams
       6.2.3.  Reserved Stream Types
   7.  HTTP Framing Layer
     7.1.  Frame Layout
     7.2.  Frame Definitions
       7.2.1.  DATA
       7.2.2.  HEADERS
       7.2.3.  CANCEL_PUSH
       7.2.4.  SETTINGS
       7.2.5.  PUSH_PROMISE
       7.2.6.  GOAWAY
       7.2.7.  MAX_PUSH_ID
       7.2.8.  Reserved Frame Types
   8.  Error Handling
     8.1.  HTTP/3 Error Codes
   9.  Extensions to HTTP/3
   10. Security Considerations
     10.1.  Server Authority
     10.2.  Cross-Protocol Attacks
     10.3.  Intermediary-Encapsulation Attacks
     10.4.  Cacheability of Pushed Responses
     10.5.  Denial-of-Service Considerations
     10.6.  Use of Compression
     10.7.  Padding and Traffic Analysis
     10.8.  Frame Parsing
     10.9.  Early Data
     10.10. Migration
     10.11. Privacy Considerations
   11. IANA Considerations
     11.1.  Registration of HTTP/3 Identification String
     11.2.  New Registries
       11.2.1.  Frame Types
       11.2.2.  Settings Parameters
       11.2.3.  Error Codes
       11.2.4.  Stream Types
   12. References
     12.1.  Normative References
     12.2.  Informative References
   Appendix A.  Considerations for Transitioning from HTTP/2
     A.1.  Streams
     A.2.  HTTP Frame Types
     A.3.  HTTP/2 SETTINGS Parameters
     A.4.  HTTP/2 Error Codes
   Acknowledgments
   Index
   Author's Address

[NOTE: This file contains the header, abstract, and table of contents
 of RFC 9114. The full specification text is available at:
   https://www.rfc-editor.org/rfc/rfc9114
   https://www.rfc-editor.org/rfc/rfc9114.txt  (text)
   https://www.rfc-editor.org/rfc/rfc9114.pdf  (PDF)

 Full document: 57 pages, June 2022
 Author: Mike Bishop (Akamai), Editor
 DOI: 10.17487/RFC9114]