Patent ID: 7711760

Claim:
A device comprising: a computer processor; a memory; a file store coupled to the computer processor, the file store arranged as a hierarchal file system and including: a plurality of files, each file of the plurality of files associated with digital signature metadata that is a hash value determined from content of the file, wherein the digital signature metadata associated with a file is invalidated if the file is at least one of created, modified, or deleted; and a plurality of directories, each directory of the plurality of directories associated with digital signature metadata that is a hash value determined from digital signature metadata of the directories and of the files that are direct descendants of the directory, wherein the digital signature metadata associated with a directory is invalid if the digital signature metadata of any of the direct descendants of the directory is invalid; and an update module coupled to the computer processor and the file store, the update module executed to: provide a high probability of a provided unique value for the file; determine if digital signature metadata of a root directory of the plurality of files and the plurality of directories is a valid hash value or an invalid value; if the digital signature metadata of the root directory is the valid hash value, then using the valid hash value to determine if an update to any of the plurality of files and plurality of directories is available; and if the digital signature metadata of the root directory is the invalid value, then examining the digital signature metadata of each directory of the plurality of directories and files descending from the root directory to determine whether the digital signature metadata of each directory is a valid hash value or an invalid value and, for all of the plurality of directories and files with a valid hash value, determining whether an update is available for the directories and the files; wherein the update module further determines what level of functionality the files stored on a client device to send files to the client device to provide desired level of functionality, determines if an update to any of the plurality of files is available by transmitting the digital signature metadata of the root directory to a server that determines the availability of the update by using digital signature metadata to access a database, and receiving an indication of the availability of the update from the server. wherein at least one file located in the hierarchal file system is undated from tagged to untagged, wherein each directory from which untagged file is a descendant is undated from tagged to untagged when the at least one file becomes untagged, and wherein the untagged directory includes digital signature metadata having a null value, wherein the digital signature metadata for a directory is determined by using same signature algorithm used for files where each file's signature as a input to signature calculation for a directory.