摘要： 提出一种基于(t, n)门限秘密共享技术的分布式口令认证密钥交换方案。用户口令的验证密钥通过秘密共享方案在服务器组内进行分配，验证任务需要t个服务器协调来完成，任意t-1个服务器合谋无法获得诚实服务器关于口令验证的任何信息。动态生成每个服务器的局部密钥，保证了方案的前向安全性。通过身份认证的各用户之间以对服务器组保密的方式交换会话密钥。该方案在DDH假设下被证明是安全的。

关键词: 秘密共享方案, 密钥交换协议, 口令认证, DDH假设

Abstract: This paper presents a distributed password authenticated key exchange protocol based on (t, n)-threshold secret sharing scheme, in which a set of t servers jointly realizes the identification, whereas any conspiracy of fewer servers gains no information about the verification data. The scheme has the property of forward secrecy. The authenticated users possess the secret session key. Under the DDH assumption, the security of the scheme is proved.

Key words: secret sharing scheme, key exchange protocol, password authentication, DDH assumption

中图分类号: 

• TP309