Classification of Hash Functions Suitable for Real-life Systems

Abstract

Cryptographic hash functions have been widely studied and are used in many current systems. Though much research has been done on the security of hash functions, system designers cannot determine which hash function is most suitable for a particular system. The main reason for this is that the current security classification does not correspond very well to the security requirements of practical systems. This paper describes a new classification which is more suitable for designing real-life systems. This classification is the result of a new theoretical classification and a new qualitative classification. We show a mapping between each class and standard protocols. In addition, we show new requirements for four types of hash function for a future standard.