MISMATCH DETECTION METHOD, MISMATCH DETECTION SYSTEM, MISMATCH DETECTION DEVICE AND PROGRAM THEREFOR

摘要

The present invention detects shared mismatches in small amounts of communication. N mismatch detection devices generate and make public a random number s_i. The n mismatch detection devices generate a shared random number s that is the sum of random numbers s₀,…,s_n-1. The n mismatch detection devices calculate a share [c]_i. The n mismatch detection devices generate a share [r]_i which becomes a random number r upon reintegration. The n mismatch detection devices calculate a share [d]_i which becomes an evaluation value d upon reintegration. A mismatch detection device receives shares [d]₁,…,[d]_n-1 from n-1 mismatch detection devices. A mismatch detection device regenerates n-k shares [d]'_k,…,[d]'_n-1 from k shares [d]₀,…,[d]_k-1. A mismatch detection device evaluates whether or not share [d]_j and share [d]'_j match concerning j=k,…,n-1.