Controlled alternate quantum walk-based block hash function

The hash function is an important branch of cryptology. The controlled quantum walk-based hash function, which is presented by Li, is a kind of novel hash function. It is safe, flexible, and compatible. All existing controlled quantum walk-based hash functions are controlled by one bit of message in each step. To process the message in batch amounts, in this paper, the controlled alternate quantum walk-based block hash function is presented by using the time-position-dependent controlled alternate quantum walk on the complete graph with self-loops. The presented hash function accelerates the hash processing dramatically, so it is more efficient. That could save many resources and execution time further.