Lecture 6 - Applications #3.2: HTTP

HTTP/1.0 Authentication

Most users of the Web will have at some time attempted to access a page, and been presented with a dialogue something like:

An initial HTTP attempt to access a "password protected" Web page of this type (without providing suitable "authentication" information) will generate an HTTP error message together with a Web page which explains the nature of the error. Typically the response headers will contain:

HTTP/1.1 401 Authorization Required
Date: Wed, 17 Mar 2004 01:17:56 GMT
Server: Apache/1.2.6
WWW-Authenticate: Basic realm="ByPassword"
Last-Modified: Mon, 15 Mar 2004 00:43:51 GMT
....etc....

In HTTP/1.0, only the Basic authentication method was available, as used in this example.

Upon receiving this error, the Web browser will normally pop up a dialog box similar to the above, collect a user-ID and password from the user, and then retry the request with an additional "Authorization: " request header containing the additional information.

Lecture 06: Applications #3.2: HTTP

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