One-Way Hash Functions With Changeable Parameters

In this paper, four new algorithms for improvements of MD5 and SHA-Keyed/Unkeyed MD5 and Keyed/Unkeyed SHA are proposed. We change the mode of ®xed retrieval of the parameters to that of dynamic retrieval of the parameters by applying a mapping between the index phrase and the parameter table. As shown in the experimental result, with 1% degradation of performance, comparing to the original algorithms, dynamic retrieval of parameters can be achieved. We believe that the security can be increased under the improvements. Ó 1999 Elsevier Science Inc. All rights reserved.