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The TCP/IP Guide  9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)       9  TCP/IP Key Applications and Application Protocols            9  TCP/IP File and Message Transfer Applications and Protocols (FTP, TFTP, Electronic Mail, USENET, HTTP/WWW, Gopher)                 9  TCP/IP World Wide Web (WWW, "The Web") and the Hypertext Transfer Protocol (HTTP)                      9  TCP/IP Hypertext Transfer Protocol (HTTP)                           9  HTTP Messages, Message Formats, Methods and Status Codes

HTTP Response Message Format 1 2 3 4 HTTP Status Code Format, Status Codes and Reason Phrases

Other, Less-Common Methods

The other methods defined by the HTTP standard are not used as often, but I will describe them briefly, as you may still encounter them from time to time.

Allows the client to request that the server send it information about available communication options. A URI of a resource may be specified to request information relevant to accessing that resource, or an asterisk (“*”) may be used to indicate that the query is about the server itself. The response includes headers that give the client more details about how the server may be accessed.

Requests that the server store the entity enclosed in the body of the request at the URL specified in the request line. The difference between a PUT and a POST is that in a PUT, the URI identifies the entity in the request, while in a POST, the URI identifies a program intended to process the entity in the request. Thus a PUT would be used to allow a file to be copied to a server, in the exact complement to how a GET requests that a file be copied to the client. A POST is used for interactive programs, as explained above.

Now, would you like people to be able to store files on your server in the same way that they request them? Neither would I. This is one primary reason why PUT is not often used. It has valid uses, such as uploading content to a Web site, and must be used with authentication in this case. However, generally speaking, storing files on a site is more often accomplished using other means, like FTP.

Requests that the specified resource be deleted. This has the same issues as PUT and is not often used for similar reasons.

Allows a client to receive back a copy of the request that it itself sent to the server, for diagnostic purposes.

HTTP Response Message Format 1 2 3 4 HTTP Status Code Format, Status Codes and Reason Phrases