The Apache JServe Protocol (AJP) is a binary protocol that can conduit inbound requests from a web server through to an application server that sits behind the web server. It also supports some monitoring in terms of the web server being able to ping the application server. AJP is typically used in a load balanced deployment where one or more front-end web servers feed requests into one or more application servers. Sessions are redirected to the correct application server using a routing mechanism wherein each application server instance gets a name which is called a route.
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