US Patent 8955084 Timestamp-based token revocation

A token used when a first device authenticates itself to a third device may be associated with a token issue timestamp. Upon receipt of an indication that all previously issued tokens are to be revoked, a second device may store a revocation timestamp. Upon receiving, from the second device, a request for establishing conditions for a file transfer, from the first device, and an indication of a token issue timestamp associated with the request, the second device may compare the token issue timestamp to the revocation timestamp. Responsive to determining, based on the comparing, that the token issue timestamp precedes the revocation timestamp, the second device may deny the request.