RFC 2068

Network Working Group
Request for Comments: 2068
Category: Standards Track

R. Fielding
UC Irvine
J. Gettys
J. Mogul
DEC
H. Frystyk
T. Berners-Lee
MIT/LCS
January 1997

Status of this Memo

This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.

Abstract

The Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypermedia information systems. It is a generic, stateless, object-oriented protocol which can be used for many tasks, such as name servers and distributed object management systems, through extension of its request methods. A feature of HTTP is the typing and negotiation of data representation, allowing systems to be built independently of the data being transferred.

HTTP has been in use by the World-Wide Web global information initiative since 1990. This specification defines the protocol referred to as "HTTP/1.1".

Table of Contents

• 1 Introduction
  • 1.1 Purpose
  • 1.2 Requirements
  • 1.3 Terminology
  • 1.4 Overall Operation
• 2 Notational Conventions and Generic Grammar
  • 2.1 Augmented BNF
  • 2.2 Basic Rules
• 3 Protocol Parameters
  • 3.1 HTTP Version
  • 3.2 Uniform Resource Identifiers
    • 3.2.1 General Syntax
    • 3.2.2 http URL
    • 3.2.3 URI Comparison
  • 3.3 Date/Time Formats
    • 3.3.1 Full Date
    • 3.3.2 Delta Seconds
  • 3.4 Character Sets
  • 3.5 Content Codings
  • 3.6 Transfer Codings
  • 3.7 Media Types
    • 3.7.1 Canonicalization and Text Defaults
    • 3.7.2 Multipart Types
  • 3.8 Product Tokens
  • 3.9 Quality Values
  • 3.10 Language Tags
  • 3.11 Entity Tags
  • 3.12 Range Units
• 4 HTTP Message
  • 4.1 Message Types
  • 4.2 Message Headers
  • 4.3 Message Body
  • 4.4 Message Length
  • 4.5 General Header Fields
• 5 Request
  • 5.1 Request-Line
    • 5.1.1 Method
    • 5.1.2 Request-URI
  • 5.2 The Resource Identified by a Request
  • 5.3 Request Header Fields
• 6 Response
  • 6.1 Status-Line
    • 6.1.1 Status Code and Reason Phrase
  • 6.2 Response Header Fields
• 7 Entity
  • 7.1 Entity Header Fields
  • 7.2 Entity Body
    • 7.2.1 Type
    • 7.2.2 Length
• 8 Connections
  • 8.1 Persistent Connections
    • 8.1.1 Purpose
    • 8.1.2 Overall Operation
      • 8.1.2.1 Negotiation
      • 8.1.2.2 Pipelining
    • 8.1.3 Proxy Servers
    • 8.1.4 Practical Considerations
  • 8.2 Message Transmission Requirements
• 9 Method Definitions
  • 9.1 Safe and Idempotent Methods
    • 9.1.1 Safe Methods
    • 9.1.2 Idempotent Methods
  • 9.2 OPTIONS
  • 9.3 GET
  • 9.4 HEAD
  • 9.5 POST
  • 9.6 PUT
  • 9.7 DELETE
  • 9.8 TRACE
• 10 Status Code Definitions
  • 10.1 Informational 1xx
    • 10.1.1 100 Continue
    • 10.1.2 101 Switching Protocols
  • 10.2 Successful 2xx
    • 10.2.1 200 OK
    • 10.2.2 201 Created
    • 10.2.3 202 Accepted
    • 10.2.4 203 Non-Authoritative Information
    • 10.2.5 204 No Content
    • 10.2.6 205 Reset Content
    • 10.2.7 206 Partial Content
  • 10.3 Redirection 3xx
    • 10.3.1 300 Multiple Choices
    • 10.3.2 301 Moved Permanently
    • 10.3.3 302 Moved Temporarily
    • 10.3.4 303 See Other
    • 10.3.5 304 Not Modified
    • 10.3.6 305 Use Proxy
  • 10.4 Client Error 4xx
    • 10.4.1 400 Bad Request
    • 10.4.2 401 Unauthorized
    • 10.4.3 402 Payment Required
    • 10.4.4 403 Forbidden
    • 10.4.5 404 Not Found
    • 10.4.6 405 Method Not Allowed
    • 10.4.7 406 Not Acceptable
    • 10.4.8 407 Proxy Authentication Required
    • 10.4.9 408 Request Timeout
    • 10.4.10 409 Conflict
    • 10.4.11 410 Gone
    • 10.4.12 411 Length Required
    • 10.4.13 412 Precondition Failed
    • 10.4.14 413 Request Entity Too Large
    • 10.4.15 414 Request-URI Too Long
    • 10.4.16 415 Unsupported Media Type
  • 10.5 Server Error 5xx
    • 10.5.1 500 Internal Server Error
    • 10.5.2 501 Not Implemented
    • 10.5.3 502 Bad Gateway
    • 10.5.4 503 Service Unavailable
    • 10.5.5 504 Gateway Timeout
    • 10.5.6 505 HTTP Version Not Supported
• 11 Access Authentication
  • 11.1 Basic Authentication Scheme
  • 11.2 Digest Authentication Scheme
• 12 Content Negotiation
  • 12.1 Server-driven Negotiation
  • 12.2 Agent-driven Negotiation
  • 12.3 Transparent Negotiation
• 13 Caching in HTTP
  • 13.1 Client Interaction
    • 13.1.1 Cache Correctness
    • 13.1.2 Warnings
    • 13.1.3 Cache-control Mechanisms
    • 13.1.4 Explicit User Agent Warnings
    • 13.1.5 Exceptions to the Rules and Warnings
    • 13.1.6 Client-controlled Behavior
  • 13.2 Expiration Model
    • 13.2.1 Server-Specified Expiration
    • 13.2.2 Heuristic Expiration
    • 13.2.3 Age Calculations
    • 13.2.4 Expiration Calculations
    • 13.2.5 Disambiguating Expiration Values
    • 13.2.6 Disambiguating Multiple Responses
  • 13.3 Validation Model
    • 13.3.1 Last-modified Dates
    • 13.3.2 Entity Tag Cache Validators
    • 13.3.3 Weak and Strong Validators
    • 13.3.4 Rules for When to Use Entity Tags and Last-modified Dates
    • 13.3.5 Non-validating Conditionals
  • 13.4 Response Cachability
  • 13.5 Constructing Responses From Caches
    • 13.5.1 End-to-end and Hop-by-hop Headers
    • 13.5.2 Non-modifiable Headers
    • 13.5.3 Combining Headers
    • 13.5.4 Combining Byte Ranges
  • 13.6 Caching Negotiated Responses
  • 13.7 Shared and Non-Shared Caches
  • 13.8 Errors or Incomplete Response Cache Behavior
  • 13.9 Side Effects of GET and HEAD
  • 13.10 Invalidation After Updates or Deletions
  • 13.11 Write-Through Mandatory
  • 13.12 Cache Replacement
  • 13.13 History Lists
• 14 Header Field Definitions
  • 14.1 Accept
  • 14.2 Accept-Charset
  • 14.3 Accept-Encoding
  • 14.4 Accept-Language
  • 14.5 Accept-Ranges
  • 14.6 Age
  • 14.7 Allow
  • 14.8 Authorization
  • 14.9 Cache-Control
    • 14.9.1 What is Cachable
    • 14.9.2 What May be Stored by Caches
    • 14.9.3 Modifications of the Basic Expiration Mechanism
    • 14.9.4 Cache Revalidation and Reload Controls
    • 14.9.5 No-Transform Directive
    • 14.9.6 Cache Control Extensions
  • 14.10 Connection
  • 14.11 Content-Base
  • 14.12 Content-Encoding
  • 14.13 Content-Language
  • 14.14 Content-Length
  • 14.15 Content-Location
  • 14.16 Content-MD5
  • 14.17 Content-Range
  • 14.18 Content-Type
  • 14.19 Date
  • 14.20 ETag
  • 14.21 Expires
  • 14.22 From
  • 14.23 Host
  • 14.24 If-Modified-Since
  • 14.25 If-Match
  • 14.26 If-None-Match
  • 14.27 If-Range
  • 14.28 If-Unmodified-Since
  • 14.29 Last-Modified
  • 14.30 Location
  • 14.31 Max-Forwards
  • 14.32 Pragma
  • 14.33 Proxy-Authenticate
  • 14.34 Proxy-Authorization
  • 14.35 Public
  • 14.36 Range
    • 14.36.1 Byte Ranges
    • 14.36.2 Range Retrieval Requests
  • 14.37 Referer
  • 14.38 Retry-After
  • 14.39 Server
  • 14.40 Transfer-Encoding
  • 14.41 Upgrade
  • 14.42 User-Agent
  • 14.43 Vary
  • 14.44 Via
  • 14.45 Warning
  • 14.46 WWW-Authenticate
• 15 Security Considerations
  • 15.1 Authentication of Clients
  • 15.2 Offering a Choice of Authentication Schemes
  • 15.3 Abuse of Server Log Information
  • 15.4 Transfer of Sensitive Information
  • 15.5 Attacks Based On File and Path Names
  • 15.6 Personal Information
  • 15.7 Privacy Issues Connected to Accept Headers
  • 15.8 DNS Spoofing
  • 15.9 Location Headers and Spoofing
• 16 Acknowledgments
• 17 References
• 18 Authors' Addresses
• 19 Appendices
  • 19.1 Internet Media Type message/http
  • 19.2 Internet Media Type multipart/byteranges
  • 19.3 Tolerant Applications
  • 19.4 Differences Between HTTP Entities and MIME Entities
    • 19.4.1 Conversion to Canonical Form
    • 19.4.2 Conversion of Date Formats
    • 19.4.3 Introduction of Content-Encoding
    • 19.4.4 No Content-Transfer-Encoding
    • 19.4.5 HTTP Header Fields in Multipart Body-Parts
    • 19.4.6 Introduction of Transfer-Encoding
    • 19.4.7 MIME-Version
  • 19.5 Changes from HTTP/1.0
  • 19.6 Additional Features
    • 19.6.1 Additional Request Methods
      • 19.6.1.1 PATCH
      • 19.6.1.2 LINK
      • 19.6.1.3 UNLINK
    • 19.6.2 Additional Header Field Definitions
      • 19.6.2.1 Alternates
      • 19.6.2.2 Content-Version
      • 19.6.2.3 Derived-From
      • 19.6.2.4 Link
      • 19.6.2.5 URI
  • 19.7 Compatibility with Previous Versions
    • 19.7.1 Compatibility with HTTP/1.0 Persistent Connections
      • 19.7.1.1 The Keep-Alive Header

• Original text document
• Complete HTML RFC (TAR, TGZ, or ZIP format)

Dies ist ein Mirror von Connected: An Internet Encyclopedia von Brent Baccala. Die offizielle Projekt-Homepage findet sich im Web unter www.freesoft.org/CIE. Dieser Mirror wurde zuletzt aktualisiert am Samstag, 28 Januar 2006 18:18 +0100.