KEY EXCHANGE DEVICE, KEY GENERATING DEVICE, KEY EXCHANGE SYSTEM, KEY EXCHANGE METHOD, AND PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide a key exchange method with which it is difficult for an attacker to obtain a shared key even when a short-term secret key is leaked to the attacker.SOLUTION: The key exchange device outputs a short-term public key Ycorresponding to a short-term secret key y, accepts a short-term public key Yof another device, and obtains a shared key corresponding to information containing the formula about a public key Rof another device, a master public key T, a corresponding value Hcorresponding to information containing the public key R, a short-term public key Y, a secret key sof the key exchange device, a short-term secret key y, and shared values c,c,c,c.