Securely Computing the n-Variable Equality Function with 2n Cards
share
Research on the area of secure multi-party computation using a deck of playing cards, often called card-based cryptograpy, started from the introduction of the "five-card trick" to compute the logical AND function by den Boar in 1989. Since then, many protocols with different properties to compute various functions have been developed. In this paper, we propose a new card-based protocol that securely computes the n-variable equality function using 2n cards. We also show that the same technique can be applied to compute any doubly symmetric function f: {0,1}^n →Z using 2n cards, and any symmetric function f: {0,1}^n →Z using 2n+2 cards.
READ FULL TEXT