METHODS AND APPARATUS FOR EFFICIENT COMPUTATION OF ONE-WAY CHAINS IN CRYPTOGRAPHIC APPLICATIONS

Techniques are disclosed for efficient computation of consecutive values of one-way chains and other one-way graphs in cryptographic applications. The one-way chain or graph may be a chain of length s having positions i=1, 2, . . . s each having a corresponding value vi associated therewith, wherein the value vi is given by vi=h(vi+1), for a given hash function or other one-way function h. A given one of the output values vi at a current position in the one-way chain may be computed utilizing a first helper value previously stored for another position in the one-way chain between the current position and an endpoint of the chain. After computation of the given output value, the positions of the helper values are adjusted so as to facilitate computation of subsequent output values.