Magnetic/optical/electronic/electro-optic type personal external storage medium e.g. universal serial bus key, for use in computer system, has processing module including sub-module creating cache file and accessing to cache file

摘要

The medium (1) has a filtering module (D) filtering a request on a file e.g. span-in file that has a digital information e.g. program, recorded in a local cache (8) and a mass storage of a remote server of a host station (5) e.g. mobile telephone. A processing module (C) processes the request on the file by a file operating and management system such that the module (C) acts as the request on the file. The module (C) has an extension sub-module that creates a cache file corresponding to a request object span-in file, in a host memory (11) and accesses to the cache file.