Looking at the other side of the HTTP client-server pair is useful to illustrate the use of invocation handlers for programming servers. Technically, a server is much the same as the client in that it reads requests, performs some processing and then sends some reply. The corresponding client behavior is to get a reply, return the result to the previous sender and send the next request.

However, the similarity ends about there. Servers have additional requirements of managing tables of connections, multiple requests, multithreading and facilitating a wider variety of processing. Invocation handlers and dispatchers provide infrastructure for satisfying all of these requirements.