proxy server

A server that receives requests intended for another server and that acts on the client's behalf (as the client's proxy) to obtain the requested service. A proxy server is often used when the client and the server are incompatible for direct connection. For example, the client is unable to meet the security authentication requirements of the server but should be permitted some services.

A firewall component that manages Internet traffic to and from a local area network (LAN) and that can provide other features, such as document caching and access control. A proxy server can improve performance by supplying frequently requested data, such as a popular Web page, and it can filter and discard requests that the owner does not consider appropriate, such as requests for unauthorized access to proprietary files. [Exchange 2003]

A server that acts as an intermediary for HTTP Web requests that are hosted by an application or a Web server. A proxy server acts as a surrogate for the content servers in the enterprise.

A server that sits between a client application, such as a web browser, and a real server. It intercepts all requests to the real server to see if it can fulfill the requests itself. If not, it forwards the request to the real server.

A server, deployed between users and a network or servers, that intercepts and terminates user requests. These requests are then forwarded, or "proxied," to the network on behalf of the user.

A program that deals with external servers on behalf of internal clients. Proxy clients talk to proxy servers, which relay approved client requests to real servers, and relay answers back to clients.