High performance pipelined architecture of Ghash

Ghash is the authentication function of GCM. In this paper, we propose a high performance pipelined architecture of Ghash. The pipelined architecture can boost the operating frequency of the hash function block that is the bottleneck for higher speed GCM hardware. The most attractive feature is our pipelined architecture based on divided-and-conquer algorithm. According to the architecture, the critical path of the multiply-adder used for Ghash is divided into 3-stage to obtain the higher throughput and reduce the time complexity. At the same, divided-and-conquer algorithm can efficiently reduce the space complexity. The proposed architecture is compared to previous work on resource consumption and throughput aspects, and evaluated by using Xilinx Virtex5. From the statistics of our analysis and implementation, the number of AND gates consumed reduces by 25%, the number of XOR gates consumed reduces by 21.4%, and the throughput increases by 12.556Gbps reaching to 43.32Gbps. This design makes it very easy to implement the low complexity and high speed architecture of Ghash, and the design adapts to high speed networks security for authentication function.