Increasing the security of hash functions

In this paper, we introduce a solution for ensuring data integrity using cryptographic one-way hash functions. The cryptographic security of such hash functions was estimated by us in detail for different kinds of attacks. We propose several new schemes for increasing the security of one-way hash functions without reformation of its internal algorithms. Also we outline schemes with the best speed and security level. We show that the Schneier method of suffix superposition has a serious drawback. In this article, we also suggest the method of constructing collision resistant one-way hash functions from standard well-known hash functions. Therefore, the proposed schemas can be used to upgrade the majority of cryptographic one-way functions, such as MD4, MD5, RIPEMD, SHA, GOST 34 11-94.