Abstract:Hash chains are widely used in various cryptographic systems such as electronic micropayments and one-time passwords etc. However, hash chains suffer from the limitation that they have a finite number of links which when used up requires the system to re-initialize new hash chains. So system design has to reduce the overhead when hash chains are re-initialized. An efficient construction which can re-initialize hash chains is proposed, and it is entirely based on one-way hash function. In the proposed construction hash chains can be securely re-initialized in a non-repudiable manner. The method will find much pragmatic application because of its efficient, secure and elegant structure.