The SIMD (single-instruction, multiple-data) architecture is implemented in many popular general-purpose processor families, including Intel Pentium. In this paper, we examine if any performance gains can be obtained in the implementation of the Secure Hash Algorithms (SHA-1, SHA-256, SHA-384, and SHA-512) and present the details of our optimization methods and implementation details. It turns out that while the hashing of a single message is slower, the hashing of 2 or 4 independent message streams can be made signicantly faster
