FSMLock: Sequential Logic Locking Case Study

J. LaPietra, M. Kurdziel (L3Harris Technologies, USA), M. Łukowiak (Rochester Inst. of Techn., USA)

FSMLock is a sequential logic locking technique that has been proposed for protection of intellectual property (IP) of finite state machine (FSM) circuits. While this technique provides security advantages over other sequential logic locking techniques, one major drawback this approach brings is the large amount of memory required for storing data of all states, transitions, and outputs. Finite state machines with input multiplexing (FSMIM) is an optimization methodology and tools that were proposed for efficient mapping of FSMs into memory. This is primarily achieved by reducing the number of effective inputs to the FSM. This paper discusses our work on integrating these two techniques in a practical case study of converting existing state machine into implementation with FSMLock with input multiplexing.