【摘要】 组播为组通信提供一个可扩展的解决方案,而组密钥管理是安全组通信最重要的组成部分。Chaddoud和Varadharajan在安全特定源组播体系结构中利用Yi,Varadharajan和Zhao的分布式公钥加密算法提出了一种信道密钥管理方案。我们首先论证在该算法中使用强的单向散列函数不仅是不必要的,而且诱发敌手利用剩余类环中的零因子对其发起一种被动攻击。其次通过重新配置系统参数,改进后的G算法既能提高抵抗零因子攻击的能力,又能保持理想的语意特性。然后对其方案中组管理者使用的加密密钥进行了简化计算,并分析了其方案不适用于大型安全组通信的原因。更多还原

【Abstract】 Multicasting is a scalable solution for group communication and group key management is the most important component of secure group communication. Using a distributed public-key encryption algorithm of Yi,Varadharajan and Zhao in the architecture of Secure Source Specific Multicast,Chaddoud and Varadharajan proposed a channel key management scheme. We first demonstrate that it is not only unnecessary to use a strong one-way hash function in the algorithm,but also subject to a passive attack on it via the zero divisors in the ring of residues. After the system parameters are reset,the improved G algorithm gains its stronger ability to resist the zero divisor attack and holds ideal semantic property. Then the computation of the encryption key used by the group manager in the scheme is simplified,and the cause of its inapplicability to large secure group communication is analyzed.更多还原