ENCRYPTION PROCESSING SYSTEM, KEY GENERATION DEVICE, KEY DEVOLVEMENT DEVICE, ENCRYPTION DEVICE, DECODING DEVICE, ENCRYPTION PROCESSING METHOD, AND ENCRYPTION PROCESSING PROGRAM

摘要

It is an object of this invention to implement a predicate encryption scheme with delegation capability. A cryptographic process is performed using dual vector spaces (dual distortion vector spaces) of a space V and a space V * paired through a pairing operation. An encryption device generates as a cipher vector a vector of the space V, the cipher vector being a vector in which transmission information is embedded. Using a predetermined vector of the space V * as a key vector, a decryption device performs the pairing operation on the cipher vector generated by the encryption device and the key vector to decrypt the cipher vector and to extract information concerning the transmission information. In particular, the encryption device and the decryption device perform the cryptographic process without using some dimensions of the space V and the space V * .