#### Alladi Ramakrishnan Hall

#### Avalanche effect by local interactions

#### Celestine P Lawrence

##### IMSc, Chennai

*The avalanche effect is a desirable property for Boolean functions in*

cryptography. For a multi-input single-output Boolean function, the

strict-avalanche criterion (SAC) requires that the output bit changes with

a 50% probability upon flipping any input bit. We investigate Boolean

functions where an input array is transformed to an output value by a

series of cellular automaton (CA) rules. We find that there is an abundance

of strong avalanche effect among CAs with just next-nearest neighbor

interactions. This work is an improvement over the knowledge that the

Rule-30 CA is useful for cryptography, and can help in engineering hardware

that is simple, energy-efficient, and ultra-fast for one-time pad

encryption.

Done