ENCRYPTION SYSTEM

摘要

It is an object to realize an inner-product predicate encryption scheme with improved flexibility without a restriction that the dimensions of an attribute vector x †’ and a predicate vector v †’ should be equivalent. A ciphertext having an element c 0 and an element c t for each index t included in a set I x†’ is decrypted with a decryption key having an element k 0 and an element k t for each index t included in a set I v†’ by computing a product of pairing operations between corresponding pairs of basis vectors on the element c 0 and the element k 0 and on the element c t and the element k t .