Patent ID: 11888968
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Digital communication (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 10:
11. A non-transitory computer readable medium storing a signature program that causes a computer to function as a signature device to perform:
an acquisition process of acquiring a signature key in which an attribute vector is set over a basis B* of a basis B and the basis B*, which are dual bases in dual vector spaces;
a signature process of generating a signature for a message by setting predicate information of arithmetic branching programs (ABP) for the signature key acquired by the acquisition process; and
an output process of outputting the signature generated by the signature process and the message,
wherein the signature key includes elements respectively corresponding to elements of the attribute vector, and in each of the element of the signature key, index information I* associated with a corresponding one of the elements of the attribute vector is set as a coefficient of one or more but not all basis vectors in the basis B*.