Collision Analysis and Improvement of a Parallel Hash Function based on Chaotic Maps with Changeable Parameters

Recently, a parallel hash function based on chaotic maps with changeable parameters was proposed by Li et al (2011, pp.1305-1312). In this paper, the security of it is analyzed and the weakness of the architecture is pointed out. It is found that the main limitations are the error using of floor, round and exclusive OR operations in the algorithm. In order to counterstrike these, some improvements are done to strength its security. Theoretical analysis and experimental results illustrate that the improved Hash function is more secure and practical than the original one. Collision Analysis and Improvement of a Parallel Hash Function based on Chaotic Maps with Changeable Parameters