Rfca: efficient, robust and flexible cipher algorithm for fpga implementation

The current Field-Programmable Gate Array (FPGA) implementation of cryptographic algorithms faces performance and security challenges because these algorithms were not originally designed to take FPGA features into account. One significant performance limitation arises from the iteration of a round function for a high round number, given the fixed structures like static substitution and diffusion primitives throughout the process. This paper introduces a new framework for a key-dependent, flexible one-round stream cipher scheme specifically designed to benefit from FPGA features. It is called RFCA. Security and performance analyses validate the effectiveness and robustness of the proposed solution, ensuring the desired cryptographic properties. In comparison with an AES implementation, RFCA is 34 times faster.