Efficient Rijndael implementation for high-speed optical networks

The current fast growing use of the Internet for commercial transactions has created large demands for data protection and network security. IPsec standard and protocols address these demands by providing different mechanisms to ensure integrity, privacy, and authentication of data when it is transmitted, or accessed, via the IP network. Encryption algorithms are by far the most important tools for network and communication security in the IPSec standard. This paper presents a summary of our work to design an efficient implementation of Rijndael algorithm. Rijndael is the new Advanced Encryption Standard adopted by the National Institute of Standards and Technology (NIST). Two different hardware implementations are presented and analyzed. In the first approach, only one lookup table is used to implement the S-Box that performs substitution for all round transformations, which is the bottleneck in the Rijndael algorithm. To achieve optimum speed of data encryption in the feedback mode, access to S-Box is pipelined between rounds. The second realization is based on systolic architecture where sets of interconnected cells are performing intermediate round transformations. Each cell consists of an S-Box instance with a small combinational circuit to run the round transformation. Verilog design code were developed and synthesized for both implementations, then compared to the existing hardware implementations. It is found that our implementation using standard cell libraries provides much faster encryption rate compared to the reported FPGA and software approach hence it can be deployed in high-speed optical networks.