Patent ID: 7549171

Claim:
A data access method between a first data processing system and a second data processing system, said second data processing system having a storage of data that is accessed by said first data processing system and which same storage of data is not maintained at said first data processing system, the method comprising: maintaining a data structure at said first data processing system, said data structure comprising access control information received from said second data processing system, said access control information corresponding to a plurality of files stored on said second data processing system and including file identifiers of the plurality of files and user identifiers of users who can access the files, wherein said access control information is available at each of said first and second data processing systems; receiving a data I/O request from an application-level program executing on said first data processing system, said data I/O request including first file identification information; retrieving first access control information from said data structure at said first data processing system based upon said first file identification information; generating a data access request including data which is associated with said data I/O request, said first access control information, and said first file identification information appended to said data; and communicating said data access request from said first data processing system to said second data processing system, wherein said second data processing system selectively performs a data operation based on a comparison of the first access control information included with the data request and second access control information available at the second data processing system.