An example embodiment of the present invention provides a process for opening and reading a file over a network, including a WAN. In the example embodiment, an edge file gateway appliance (or server) receives a request from an application such as a tile manager to open a file cached with the edge file gateway appliance at one point on a network and stored on a file server connected to a central server appliance (or server) at another point on the network. The edge file gateway appliance then forwards the request to open the file to the central server appliance, along with any offsets and lengths stored from any previous requests to read the file. The central server appliance responds by sending any file data described in the stored offsets and lengths to the edge file gateway appliance. Then when the edge file gateway appliance receives a read request from an application, the edge file gateway appliance stores the offset and length for the request, if a predefined storage limit is not exceeded, and attempts t
