Description

Glossary

RFCs

Publications

Obsolete RFCs

Description:

RFC 1945:

HTTP is an application level protocol with the lightness and speed necessary for distributed, collaborative, hypermedia information systems. HTTP has been in use by the World-Wide Web global information initiative since 1990.

Secure HTTP (S-HTTP) is a secure message-oriented communications protocol designed for use in conjunction with HTTP. It is designed to coexist with HTTP's messaging model.

HTTPS is HTTP encapsulated in an SSL/TLS stream.

HTTP message:

Methods:

Header fields:

Status code categories:

HTTP status codes:

Glossary:

Age.
The elapsed time since a response was sent by, or successfully validated with, the origin server.

Cache.
(RFC 1945) A program's local store of response messages and the subsystem that controls its message storage, retrieval, and deletion. A cache stores cachable responses in order to reduce the response time and network bandwidth consumption on future, equivalent requests. Any client or server may include a cache, though a cache cannot be used by a server while it is acting as a tunnel.

Client.
(RFC 1945) An application program that establishes connections for the purpose of sending requests.

Entity.
(RFC 1945) A particular representation or rendition of a data resource, or reply from a service resource, that may be enclosed within a request or response message. An entity consists of metainformation in the form of entity headers and content in the form of an entity body.

Explicit expiration time.
(RFC 2068) The time at which the origin server intends that an entity should no longer be returned by a cache without further validation.

First-hand.
(RFC 2068) A response is first-hand if it comes directly and without unnecessary delay from the origin server, perhaps via one or more proxies. A response is also first-hand if its validity has just been checked directly with the origin server.

Fresh.
(RFC 2068) A response is fresh if its age has not yet exceeded its freshness lifetime.

Freshness lifetime.
(RFC 2068) The length of time between the generation of a response and its expiration time.

Gateway.
(RFC 1945) A server which acts as an intermediary for some other server. Unlike a proxy, a gateway receives requests as if it were the origin server for the requested resource; the requesting client may not be aware that it is communicating with a gateway. Gateways are often used as server-side portals through network firewalls and as protocol translators for access to resources stored on non-HTTP systems.

Heuristic expiration time.
(RFC 2068) An expiration time assigned by a cache when no explicit expiration time is available.

Proxy.
(RFC 1945) An intermediary program which acts as both a server and a client for the purpose of making requests on behalf of other clients. Requests are serviced internally or by passing them, with possible translation, on to other servers. A proxy must interpret and, if necessary, rewrite a request message before forwarding it. Proxies are often used as client-side portals through network firewalls and as helper applications for handling requests via protocols not implemented by the user agent.

Origin server.
(RFC 1945) The server on which a given resource resides or is to be created.

Semantically transparent.
(RFC 2068) A cache behaves in a "semantically transparent" manner, with respect to a particular response, when its use affects neither the requesting client nor the origin server, except to improve performance. When a cache is semantically transparent, the client receives exactly the same response (except for hop-by-hop headers) that it would have received had its request been handled directly by the origin server.

Server.
(RFC 1945) An application program that accepts connections in order to service requests by sending back responses.

Stale.
(RFC 2068) A response is stale if its age has passed its freshness lifetime.

Tunnel.
(RFC 1945) A tunnel is an intermediary program which is acting as a blind relay between two connections. Once active, a tunnel is not considered a party to the HTTP communication, though the tunnel may have been initiated by an HTTP request. The tunnel ceases to exist when both ends of the relayed connections are closed. Tunnels are used when a portal is necessary and the intermediary cannot, or should not, interpret the relayed communication.

User agent.
(RFC 1945) The client which initiates a request. These are often browsers, editors, spiders (web-traversing robots), or other end user tools.

Validator.
(RFC 2068) A protocol element (e.g., an entity tag or a Last-Modified time) that is used to find out whether a cache entry is an equivalent copy of an entity.

Variant.
(RFC 2068) A resource may have one, or more than one, representation(s) associated with it at any given instant. Each of these representations is termed a `variant.' Use of the term `variant' does not necessarily imply that the resource is subject to content negotiation.

RFCs:

[RFC 1945] Hypertext Transfer Protocol -- HTTP/1.0.

• Category: Informational.

[RFC 2145] Use and interpretation of HTTP version numbers.

• Category: Informational.

[RFC 2169] A Trivial Convention for using HTTP in URN Resolution.

• Category: Experimental.

[RFC 2227] Simple Hit-Metering and Usage-Limiting for HTTP.

• Category: Standards Track.

[RFC 2291] Requirements for a Distributed Authoring and Versioning Protocol for the World Wide Web.

• Category: Informational.

[RFC 2295] Transparent Content Negotiation in HTTP.

• Category: Experimental.

[RFC 2296] HTTP Remote Variant Selection Algorithm -- RVSA/1.0.

• Category: Experimental.

[RFC 2310] The Safe Response Header Field.

• Category: Experimental.

[RFC 2324] Hyper Text Coffee Pot Control Protocol (HTCPCP/1.0).

• Category: Informational.

[RFC 2518] HTTP Extensions for Distributed Authoring -- WEBDAV.

• Category: Standards Track.
• Defines URI schemes dav: and opaquelocktoken:.

[RFC 2560] X.509 Internet Public Key Infrastructure Online Certificate Status Protocol - OCSP.

• Category: Standards Track.
• Defines MIME media subtypes application/ocsp-request, application/ocsp-response.

[RFC 2585] Internet X.509 Public Key Infrastructure Operational Protocols: FTP and HTTP.

• Category: Standards Track.

[RFC 2616] Hypertext Transfer Protocol -- HTTP/1.1.

• Category: Standards Track.
• Defines MIME media subtypes application/http and message/http.
• Defines URI scheme http:.
• Obsoletes:
  RFC 2068.

[RFC 2617] HTTP Authentication: Basic and Digest Access Authentication.

• Category: Standards Track.
• Obsoletes:
  RFC 2069.

[RFC 2660] The Secure HyperText Transfer Protocol.

• Category: Experimental.
• Defines MIME media subtype message/s-http.

[RFC 2774] An HTTP Extension Framework.

• Category: Experimental.

[RFC 2817] Upgrading to TLS Within HTTP/1.1.

• Category: Standards Track.
• Updates:
  RFC 2616.

[RFC 2818] HTTP Over TLS.

• Category: Informational.
• Defines URI scheme https:.

[RFC 2936] HTTP MIME Type Handler Detection.

• Category: Informational.

[RFC 2964] Use of HTTP State Management.

• BCP: 44.

[RFC 2965] HTTP State Management Mechanism.

• Category: Standards Track.
• Obsoletes:
  RFC 2109.

[RFC 3143] Known HTTP Proxy/Caching Problems.

• Category: Informational.

[RFC 3205] On the use of HTTP as a Substrate.

• BCP: 56.

[RFC 3229] Delta encoding in HTTP.

• Category: Standards Track.

[RFC 3230] Instance Digests in HTTP.

• Category: Standards Track.

[RFC 3253] Versioning Extensions to WebDAV (Web Distributed Authoring and Versioning).

• Category: Standards Track.

[RFC 3648] Web Distributed Authoring and Versioning (WebDAV) Ordered Collections Protocol.

• Category: Standards Track.

[RFC 3675] .sex Considered Dangerous.

• Category: Informational.

[RFC 3875] The Common Gateway Interface (CGI) Version 1.1.

• Category: Informational.

[RFC 4130] MIME-Based Secure Peer-to-Peer Business Data Interchange Using HTTP, Applicability Statement 2 (AS2).

• Category: Standards Track.

[RFC 4169] Hypertext Transfer Protocol (HTTP) Digest Authentication Using Authentication and Key Agreement (AKA) Version-2.

• Category: Informational.

[RFC 4236] HTTP Adaptation with Open Pluggable Edge Services (OPES).

• Category: Standards Track.

Publications:

Obsolete RFCs:

[RFC 2068] Hypertext Transfer Protocol -- HTTP/1.1.

• Category: Standards Track.
• Obsoleted by:
  RFC 2616.

[RFC 2069] An Extension to HTTP : Digest Access Authentication.

• Category: Standards Track.
• Obsoleted by:
  RFC 2617.

[RFC 2109] HTTP State Management Mechanism.

• Category: Standards Track.
• Obsoleted by:
  RFC 2965.

Description

Glossary

RFCs

Publications

Obsolete RFCs