Research On Certiifcateless Proxy Re-signature Basd On Cetrificateless Public Cryptosystem

Proxy re-signature is a special kind of digital signature，allows a semi-trustedproxy with some informationto transform a delegatee’s signature into a delegator’ssignature on the same message. The proxy， however, cannot generate arbitrarysignatures on behalf of either the delegatee or the delegator. Due to thetransformation function，proxy re-signature schemes are very useful and can beapplied in many applications， including simplifying certificate management，providing a proof for a path that has been taken，constructing a Digital RightsManagement (DRM) interoperable system.Existence of the complexity of the problem of key escrow and certificatemanagement for proxy re-signature，a new type of public key cryptosystem calledCertificateless Public Key Cryptography was introduced by AI-Riyami andPaterson．In Certificateless Public Key Cryptography，the Key Generation Center cannot get access to any user’s private key． The Certificateless Public KeyCryptography to solve the complex problem of key escrow and certificatemanagement, more efficient than traditional PKI public key cryptography system,security identity-based public key cryptosystem. The certificateless proxyre-signatures scheme based on standard model is proposed using of bilinear mappingtechnology and standard model framework proposed by Waters，finally，the securityof the scheme is proven．Under the standard model, it proves that it is provablesecure against adaptive chosen message attack under the hardness assumptions ofNGBDH problem and Many-DH problem. Therefore, the certificate public keycryptosystem can be applied to environmental conditions that require low bandwidthand low processing capacity of mobile devices, wireless sensor networks.Defect of the proxy in the process of conversion signature signer can get themessage， using the proposed certificateless proxy re-signature scheme， weproposed certificateless blind proxy re-signatures extended using the idea of blindsignature， and in the standard model to prove that the scheme security. Under thestandard model，it proves that it is provable secure against adaptive chosen messageattack under the hardness assumptions of NGBDH problem and Many-DH problem.