A transparent replication of HTTP service

We developed Web++, a prototype system based on user-transparent geographic replication which aims at improving the response time and the reliability of the HTTP service. Web++ extends the current Web client/server architecture with additional capabilities. The extension is provided via Java servlets at the server side and applets at the client side. The servlets pre-process the requested documents such that each logical URL is replaced by a list of physical URLs corresponding to the list of the resource's replica. An applet is automatically downloaded to the client machines together with the first request of each new user session. For subsequent requests within a user session, the applet chooses the physical URT, that corresponds to a resource held by an available server that is expected to deliver the best response time for the server