A METHOD, APPARATUS AND COMPUTER PROGRAM FOR REDUCING DATA TRANSMITTED OVER AN EXTERNAL COMMUNICATION LINK FROM A FIRST APPLICATION RESIDENT IN A FIRST COMPUTER TO A SECOND APPLICATION RESIDENT IN A SECOND COMPUTER

A method, apparatus and computer program product for reducing the data transmitted over an external communication link from a first application resident in a first computer to a second application resident in a second computer. The method, apparatus and computer program product include storing a data stream from the first application to be provided to the second application in response to a request from the second application in a cache resident in the first computer to create a server base cache entry and in a cache resident in the second computer to create a client base cache entry. Requests from the second application are interrogated to determine if a client base cache entry corresponding to the interrogated request exists and to determine if a server base cache entry corresponding to the interrogated request exists. The response data stream is intercepted prior to transmission of the response on the external communication link and compared to the server base cache entry to provide difference data corresponding to the difference between the intercepted response and the server base cache entry. The difference data is sent over the external communication link and acquired by the second computer which reconstructs the response data stream by combining the client base cache entry with the difference data to create a response data stream which is provided to the second application.