一种安全的分布式会议密钥分配方案及其实现

结合基于可验证秘密共享技术的安全多方计算和知识证明,提出了一种计算安全的分布式会议密钥分配方案,该方案具有结构简单、安全性强等特点。分析表明,即使方案中实施密钥分配的服务器组中有部分服务器为入侵者成功控制,会议的所有诚实用户仍可得到关于会议的正确的密钥;在Diffie HellmenDecisional问题假设下,任何窃听者均无法得到有关会议密钥的任何信息,在随机Oracle模型下,主动攻击者也无法成功进行任何假冒。实验表明,该方案效率较高,有着较强的实用性。

New scheme of a distributed conference key distribution and its implementation

A distributed conference key distribution system is introduced. The system utilizes secure multi-party computation scheme by virtue of Feldman's (t+1, n) VSS to perform the conference key computation such that a key can be obtained in a distributed fashion in which any key of servers is required to perform the computation. By runing the protocal, every honest user of a given conference can get a common key, even if a minority of servers malfunction or misbehave. This scheme does not rely on any unproven cryptographic assumptions or on the availability of any tamper -proof hardware. By using zero knowledge proof, any corrupted information and incorrect results can be detected. And by distributing the sensitive security information across several servers and never reconstructing and key at a single location, the compromise of a few servers will not compromise the privacy of any key. The scheme is implemented in a distributed environment. By conducting a number of experiments in the fault-free case and various fault scenarios, it is shown that the scheme is practicable and efficient.