Grover on SIMON

Understand

For any symmetric key cryptosystem with $n$-bit secret key, the key can be recovered in $O(2^{n/2})$ exploiting Grover search algorithm, resulting in the effective key length to be half.

• In this direction, subsequent work has been done on AES and some other block ciphers.
• On the other hand, lightweight ciphers like SIMON was left unexplored.
• In this backdrop, we present Grover's search algorithm on all the variants of SIMON and enumerate the quantum resources to implement such attack in terms of NOT, CNOT and Toffoli gates.