FILE SHARING SYSTEM, SHARED FILE SERVER DEVICE, FILE SHARING METHOD, ACCESS CONTROL METHOD OF SHARED FILE SERVER DEVICE, AND PROGRAMS THEREOF

PROBLEM TO BE SOLVED: To provide a file sharing system in which a user can flexibly set a rule for access control to a shared file, and encryption/decryption of file can be made without the user preparing a mechanism for the encryption/decryption nor the user performing a special operation for the encryption/decryption and performing key management. SOLUTION: The system is made up of a shared file server device comprising a shared folder, which has been created by a user using an arbitrary access condition as a folder name beforehand, for setting an access condition to a file by uploading the file, an encryption processing part for making the file into encryption data using an encryption key corresponding to the access condition, and a decryption processing part for decrypting the encryption data to the file using a decryption key corresponding to the encryption key when the attribute information of a user who tries to access the file that has been made into the encryption data satisfies the access condition, a key management server device for creating the encryption key and the decryption key, and an information management server device for storing attribute information of each user. COPYRIGHT: (C)2011,JPO&INPIT