US Patent 7139811 Double-proxy remote data access system

A method for enabling access to a data resource, which is held on a file server (25) on a first local area network (LAN) (21a), by a client (28) on a second LAN (21b). A proxy receiver (48) on the second LAN (21b) intercepts a request for the data resource submitted by the client (28) and transmits a message via a wide area network (WAN) (29) to a proxy transmitter (52) on the first LAN (21a), requesting the data resource. The proxy transmitter (52) retrieves a replica of the data resource from the file server (25) and conveys the replica of the data resource over the WAN (29) to the proxy receiver (48), which serves the replica of the data resource from the proxy receiver (48) to the client (28) over the second LAN (21b).