The scheme is based on certificateless cryptosystem, so it can overcome the key escrow of ID-based cryptosystem, and avoid the public key management and storage of certificate-based cryptosys…

方案基于无证书的密码体制，克服了基于身份的密码体制的密钥托管问题，避免基于证书密码体制的公钥存储和管理问题。

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A new hierarchical identity based (ID-based) cryptosystem is proposed, including hierarchical ID-based encryption and signature.

提出一个基于分级身份的密码系统：包括分级的基于身份的加密和签名方案。

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