Lightweight Hash Function based on Fermat Number Transform (FNT)

This paper presents a lightweight hash function using the Fermat number transform (FNT). The FNT is one of the most important number-theoretic transforms, with many applications in digital signal processing. It can be implemented using only addition, subtraction and shifting without any multiplication, making it suitable for lightweight hash functions. In this work, the FNT is used as the core of a 128-bit hash function with a simple structure, and some of its key properties are evaluated. FNT-based lightweight hash functions can offer good security with simple structures.