Book Cipher with Infinite Key Space

The most efficient attack on symmetric-key systems is an exhaustive key search. A novel encryption method with infinite key space is presented by modify traditional book cipher. Infinite key space means the unbounded entropy of the key space, which can frustrate any exhaustive key search. Moreover, this book cipher is immune from frequency analysis. Experimental results show that both encryption and decryption have very high rates of data throughput while compared with DES. High efficiency makes it suitable for some computing power limited environment.