关键词: 身份加密,分布式,密钥生成

Abstract: According to the decentralization theory of network central warfare,we proposed a distributed private-key extraction algorithm for Lewko-Waters’s identity-based encryption because the sole key generating center of identity-based encryption is likely attacked.In this scheme,master key is in charge of both key generating center and key privacy authority.User’s private key can be extracted and supervised by key generating center from a number of key privacy authorities distributing all over the network.It could be available to strengthen the survivability and robustness of key management system.Finally we proved their IND-CPA security,i.e.the indistinguishability of ciphertext under chosen plaintext attack,in the normal model and also performed a comparative analysis of the algorithm.As you can see,it can be helpful to accomplish key escrow.

Key words: Identity-based encryption,Distributed key extraction,Key escrow