一种改进的RC（3,7）安全协议

针对在无条件安全通信中,现有的俄罗斯纸牌协议在3个游戏者和7张纸牌的情况下（RC（3,7）协议）显著存在通信信息冗余的问题,提出一种消息构造算法和一组发送规则.首先计算最小信息集合,然后给出通信数据,最后通信方发送基于最小信息集的消息,这样就形成了一种改进的RC（3,7）协议.通过形式化推理的方式证明了新算法的有效性,在此基础上证明了新协议的有效性.为通信各方建立了博弈模型,并对模型的2种可能模式进行匹配,通过这种方式证明了该协议的安全性.结果表明：与原始协议比较,改进的RC（3,7）协议应用于身份认证具有更加安全、更少信息冗余等特点.

An improved RC(3,7) security protocol

In order to reduce the information redundancy in the Russian Card protocols with 3 players and 7 cards(RC(3,7) protocols,for short),an algorithm was proposed to create communication messages.A series of rules were used to send the messages.The first step was to compute the minimizing set.The second was to produce the communication data based on the minimizing set.The last was to exchange the minimizing-set-based messages.As a result,a novel improved RC(3,7) protocol was obtained.The correctness of the improved protocol and the new algorithm were proved by using formal deduction technique.What’s more,a game model of the partners of the communication was constructed.Two possible modes of this model were matched so that the security of the protocol was proved by this way.The theorems indicate that the improved version of this protocol is more suitable than the original version for ID authentication,due to its less information redundancy as well as its security.