In key escrow field it is important to solve the problem thatuser's secret key completely depends on the trusted escrow agency. In 1995, some methods of solving the problem were presented. But these methods are no...In key escrow field it is important to solve the problem thatuser's secret key completely depends on the trusted escrow agency. In 1995, some methods of solving the problem were presented. But these methods are no better than that of directly using threshold cryptography. In this paper, we present a common pattern of threshold key escrow scheme based on public key cryptosystem, and a detailed design based on the improved RSA algorithm is given. The above problem is solved by this scheme.展开更多
Attribute-based encryption(ABE) supports the fine-grained sharing of encrypted data.In some common designs,attributes are managed by an attribute authority that is supposed to be fully trustworthy.This concept implies...Attribute-based encryption(ABE) supports the fine-grained sharing of encrypted data.In some common designs,attributes are managed by an attribute authority that is supposed to be fully trustworthy.This concept implies that the attribute authority can access all encrypted data,which is known as the key escrow problem.In addition,because all access privileges are defined over a single attribute universe and attributes are shared among multiple data users,the revocation of users is inefficient for the existing ABE scheme.In this paper,we propose a novel scheme that solves the key escrow problem and supports efficient user revocation.First,an access controller is introduced into the existing scheme,and then,secret keys are generated corporately by the attribute authority and access controller.Second,an efficient user revocation mechanism is achieved using a version key that supports forward and backward security.The analysis proves that our scheme is secure and efficient in user authorization and revocation.展开更多
In the realm of vehicular ad hoc networks(VANETs),data aggregation plays a pivotal role in bringing together data from multiple vehicles for further processing and sharing.Erroneous data feedback can significantly imp...In the realm of vehicular ad hoc networks(VANETs),data aggregation plays a pivotal role in bringing together data from multiple vehicles for further processing and sharing.Erroneous data feedback can significantly impact vehicle operations,control,and overall safety,necessitating the assurance of security in vehicular data aggregation.Addressing the security risks and challenges inherent in data aggregation within VANETs,this paper introduces a blockchain-based scheme for secure and anonymous data aggregation.The proposed scheme integrates cloud computing with blockchain technology,presenting a novel blockchain-based data aggregation system that robustly supports efficient and secure data collection in VANETs.Leveraging key escrow resilience mechanisms,the solution ensures the security of system keys,preventing the security problems caused by keys generated by third parties alone in the past.Furthermore,through secondary data aggregation,fine-grained data aggregation is achieved,providing effective support for cloud services in VANETs.The effectiveness of the proposed scheme is confirmed through security analysis and performance evaluations,demonstrating superior computational and communication efficiency compared existing alternatives.展开更多
Key agreement protocols are essential for secure communications. In this paper, to solve the inherent key escrow problem of identity-based cryptography, an escrow-free certificate-based authenticated key agreement （C...Key agreement protocols are essential for secure communications. In this paper, to solve the inherent key escrow problem of identity-based cryptography, an escrow-free certificate-based authenticated key agreement （CB-AK） protocol with perfect forward secrecy is proposed. Our protocol makes use of pairings on elliptic curves. The protocol is described and its properties are discussed though comparison with Smart＇s protocol.展开更多
Many identity-based signature （IBS） schemes solving key escrow were proposed, But the updating of the private keys wasn＇t discussed in these literatures. For the problem of key update, an identity-based key-insulat...Many identity-based signature （IBS） schemes solving key escrow were proposed, But the updating of the private keys wasn＇t discussed in these literatures. For the problem of key update, an identity-based key-insulated signature scheme with secure key-updates has been proposed. But their scheme inherited the key escrow property. In this paper, we propose a new identity-based strong key-insulated signature scheme without key escrow. It makes the IBS scheme more applicable to the real world. After analyzing the security and the performance, an application example in E-passport passive authentication scenario is described.展开更多
In current cloud computing system, large amounts of sensitive data are shared to other cloud users. To keep these data confidentiality, data owners should encrypt their data before outsourcing. We choose proxy reencry...In current cloud computing system, large amounts of sensitive data are shared to other cloud users. To keep these data confidentiality, data owners should encrypt their data before outsourcing. We choose proxy reencryption （PRE） as the cloud data encryption technique. In a PRE system, a semi-trusted proxy can transform a ciphertext under one public key into a ciphertext of the same message under another public key, but the proxy cannot gain any information about the message. In this paper, we propose a certificateless PRE （CL-PRE） scheme without pairings. The security of the proposed scheme can be proved to be equivalent to the computational Dire- Hellman （CDH） problem in the random oracle model. Compared with other existing CL-PRE schemes, our scheme requires less computation cost and is significantly more efficient. The new scheme does not need the public key certificates to guarantee validity of public keys and solves the key escrow problem in identity-based public key cryptography.展开更多
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 69772037, 60072018).
文摘In key escrow field it is important to solve the problem thatuser's secret key completely depends on the trusted escrow agency. In 1995, some methods of solving the problem were presented. But these methods are no better than that of directly using threshold cryptography. In this paper, we present a common pattern of threshold key escrow scheme based on public key cryptosystem, and a detailed design based on the improved RSA algorithm is given. The above problem is solved by this scheme.
基金supported by the NSFC(61173141,U1536206,61232016, U1405254,61373133,61502242,61572258)BK20150925+3 种基金Fund of Jiangsu Engineering Center of Network Monitoring(KJR1402)Fund of MOE Internet Innovation Platform(KJRP1403)CICAEETthe PAPD fund
文摘Attribute-based encryption(ABE) supports the fine-grained sharing of encrypted data.In some common designs,attributes are managed by an attribute authority that is supposed to be fully trustworthy.This concept implies that the attribute authority can access all encrypted data,which is known as the key escrow problem.In addition,because all access privileges are defined over a single attribute universe and attributes are shared among multiple data users,the revocation of users is inefficient for the existing ABE scheme.In this paper,we propose a novel scheme that solves the key escrow problem and supports efficient user revocation.First,an access controller is introduced into the existing scheme,and then,secret keys are generated corporately by the attribute authority and access controller.Second,an efficient user revocation mechanism is achieved using a version key that supports forward and backward security.The analysis proves that our scheme is secure and efficient in user authorization and revocation.
基金supported by the National Natural Science Foundation of China(61662089).
文摘In the realm of vehicular ad hoc networks(VANETs),data aggregation plays a pivotal role in bringing together data from multiple vehicles for further processing and sharing.Erroneous data feedback can significantly impact vehicle operations,control,and overall safety,necessitating the assurance of security in vehicular data aggregation.Addressing the security risks and challenges inherent in data aggregation within VANETs,this paper introduces a blockchain-based scheme for secure and anonymous data aggregation.The proposed scheme integrates cloud computing with blockchain technology,presenting a novel blockchain-based data aggregation system that robustly supports efficient and secure data collection in VANETs.Leveraging key escrow resilience mechanisms,the solution ensures the security of system keys,preventing the security problems caused by keys generated by third parties alone in the past.Furthermore,through secondary data aggregation,fine-grained data aggregation is achieved,providing effective support for cloud services in VANETs.The effectiveness of the proposed scheme is confirmed through security analysis and performance evaluations,demonstrating superior computational and communication efficiency compared existing alternatives.
基金Supported by the National Natural Science Founda-tion of China (60225007, 60572155) and the Science and Technology Research Project of Shanghai (04DZ07067)
文摘Key agreement protocols are essential for secure communications. In this paper, to solve the inherent key escrow problem of identity-based cryptography, an escrow-free certificate-based authenticated key agreement （CB-AK） protocol with perfect forward secrecy is proposed. Our protocol makes use of pairings on elliptic curves. The protocol is described and its properties are discussed though comparison with Smart＇s protocol.
基金Supported by the Science and Technology Planned Projects of Wuhan, China (20061005119)
文摘Many identity-based signature （IBS） schemes solving key escrow were proposed, But the updating of the private keys wasn＇t discussed in these literatures. For the problem of key update, an identity-based key-insulated signature scheme with secure key-updates has been proposed. But their scheme inherited the key escrow property. In this paper, we propose a new identity-based strong key-insulated signature scheme without key escrow. It makes the IBS scheme more applicable to the real world. After analyzing the security and the performance, an application example in E-passport passive authentication scenario is described.
基金the National Natural Science Foundation of China(No.61133014)
文摘In current cloud computing system, large amounts of sensitive data are shared to other cloud users. To keep these data confidentiality, data owners should encrypt their data before outsourcing. We choose proxy reencryption （PRE） as the cloud data encryption technique. In a PRE system, a semi-trusted proxy can transform a ciphertext under one public key into a ciphertext of the same message under another public key, but the proxy cannot gain any information about the message. In this paper, we propose a certificateless PRE （CL-PRE） scheme without pairings. The security of the proposed scheme can be proved to be equivalent to the computational Dire- Hellman （CDH） problem in the random oracle model. Compared with other existing CL-PRE schemes, our scheme requires less computation cost and is significantly more efficient. The new scheme does not need the public key certificates to guarantee validity of public keys and solves the key escrow problem in identity-based public key cryptography.
