为了满足群组通信的高安全性,将超椭圆曲线密码体制与Schnorr数字签名体制相结合,设计了一个高安全的同时具有(f,n)门限签密和(k,l)门限共享验证功能的门限群签密方案。该方案克服了彭等人和Wang等人方案的安全缺陷,利用Desmedt等人的密钥重新分配协议的思想实现了门限签密和门限解签密的密钥先应式秘密共享。与现有的面向群组通信的广义门限签密方案相比,该方案能避免恶意信息的攻击,能抵抗内部欺诈和外部攻击,具有更小的通信代价和更高的安全性,特别适用于解决带宽受限网络的安全问题。
In order to meet the high security of group communication, by combining hyperelliptic curve cryptosystem with Schnmx' s signature schemes, this paper proposed a high security group signeryption scheme with a (t,n) threshold signcryption and a (k,1) threshold verification. This scheme improved the security defects of Peng et al. , scheme and Wang et al. , scheme. It achieved proactive secret sharing of secrets of threshold signcryption and threshold unsigncryption by Desmedt et al. , secret re- distribution protocol. The new scheme can avoid the attack of the evil information and provide the capability of detecting cheating and identifying the cheater besides the property which threshold group signeryption should have. It has lower communication cost and higher security which is especially suitable for solving security problems of the network with limited resource.