Patent ID: 8078726

Claim:
A computer-implemented method comprising: receiving, at a computer system, a file request from a program on the computer system, the file request comprising a first message digest and a location; determining whether a file having a second message digest corresponding to the first message digest is available in a storage area of the computer system; when the second message digest corresponds to the first message digest: producing a fourth message digest of the file in the storage area using a hash function, comparing the fourth message digest with the first message digest, and responsive to the fourth message digest corresponding to the first message digest, providing the file from the storage area; and when the second message digest does not correspond to the first message digest: retrieving the file from the location; storing the retrieved file in the storage area; producing a third message digest from the retrieved file; comparing the third message digest with the first message digest; responsive to the third message digest corresponding to the first message digest, providing the retrieved file; and providing an error message when the third message digest does not correspond to the first message digest.