A method and system for exchanging information between processing servers. Both a processing request for a processing of data and a first key identifying the processing of data are received at a middleware server from a first application server. In response to receiving both the processing request and the first key, the processing request and a second key are sent from the middleware server to a second application server. The second key differs from the first key. After sending the processing request and the second key to the second application server, an acceptance response indicating that the processing request has been accepted by the second server is received by the middleware server from the second application server. In response to receiving the acceptance response from the second application server, the acceptance response is sent by the middleware server to the first application server.