可再生散列链的精巧构造

散列(hash)链被广泛应用于电子微支付、一次性口令等多种密码学系统中。然而，因为散列链存在有限长度的限制，当链上的散列值被用尽的时候，系统需要再生新的散列链，所以系统的设计需要尽量降低再生散列链时导致的额外开销。该文提出一种高效的完全基于单向散列函数的可再生散列链的构造方法。而且，这种构造方法能够以不可否认的方式安全地再生散列链。它的高效、安全和精巧的结构将为散列链的实际应用提供广阔的前景。

An Elegant Construction of Re-initializable Hash Chains

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.