Information servers maintain the information on the WWW and are capable of processing a client reque

Hypertext Transport Protocol (HTTP) is the standard protocol for communication with an information server on the WWW.

HTTP has communication methods that allow clients to request data from a server and send information to the server.

Alternatively, the profile information may be forwarded to an advertiser or advertising agency that evaluates and forwards back an advertisement for the proxy to transmit to the user.

This invention relates to the field of computer software, and, more specifically, to advertising on the internet.

The HTTP server responds to the client by sending a status of the request and the requested information.

The connection is then terminated between the client and the HTTP server.

A client request therefore, consists of establishing a connection between the client and the HTTP server, performing the request, and terminating the connection.

The HTTP server does not retain any information about the request after the connection has been terminated.

HTTP is, therefore, a stateless protocol.

That is, a client can make several requests of an HTTP server, but each individual request is treated independent of any other request.

The server has no recollection of any previous request.

Instead of transmitting the information from the server that maintains the information, some systems utilize what is referred to as a proxy.

Referring to FIG. 1, a proxy 102 is a server that carries out requests transmitted to it (i.e., from client 100), keeping copies of fetched documents or information for some time so that they can be accessed more quickly in the future, speeding up access for commonly requested information.

This maintaining of information and fetched documents by the proxy 102 is referred to as caching and the information maintained in the proxy 102 is referred to as a cache or proxy cache.

To protect information in internal computer networks from external access, a firewall is utilized.

A firewall is a mechanism that blocks access between the client and the server.

To provide limited access to information, a proxy or proxy server may sit atop a firewall and act as a conduit, providing a specific connection for each network connection.

Proxy software retains the ability to communicate with external sources, yet is trusted to communicate with the internal network.

For example, proxy software may require a username and password to access certain sections of the internal network and completely block other sections from any external access.

An addressing scheme is employed to identify Internet resources (e.g., HTTP server, file or program).

This addressing scheme is called Uniform Resource Locator (URL).

A URL contains the protocol to use when accessing the server (e.g., HTTP), the Internet domain name of the site on which the server is running, the port number of the server, and the location of the resource in the file structure of the server.

The WWW uses a concept known as hypertext.

Hypertext provides the ability to create links within a document to move directly to other information.

To activate the link, it is only necessary to click on the hypertext link (e.g., a word or phrase).

The hypertext link can be to information stored on a different site than the one that supplied the current information.

A URL is associated with the link to identify the location of the additional information.

When the link is activated, the client's browser uses the link to access the data at the site specified in the URL.

If the client request is for a file, the HTTP server locates the file and sends it to the client.