The improved elliptic curve digital signature algorithm

ECDSA is the first successful algorithm that based on ECC. It was accepted by ANSI, IEEE, NIST and ISO as the standard signature algorithm. In this paper, ECDSA was analyzed and improved. The improved algorithms reduce the computational cost while keeping the same security as original ECDSA. They are suitable for the users who have limited compute capacity in different cases. The performance data of each algorithm was presented also.