In a strong designated verifier proxy signature scheme, a proxy signer can generate proxy signature on behalf of an original signer, but only the designated verifier can verify the validity of the proxy signature. In ...In a strong designated verifier proxy signature scheme, a proxy signer can generate proxy signature on behalf of an original signer, but only the designated verifier can verify the validity of the proxy signature. In this paper, we first define the security requirements for strong designated verifier proxy signature schemes. And then we construct an identity-based strong designated verifier proxy signature scheme. We argue that the proposed scheme satisfies all of the security requirements.展开更多
How to protect the security of web application code and sensitive data has become one of the primary concerns in web services.In this paper,symmetric cryptosystem combined with identity-based public key cryptosystem i...How to protect the security of web application code and sensitive data has become one of the primary concerns in web services.In this paper,symmetric cryptosystem combined with identity-based public key cryptosystem is proposed to protect web application programs and sensitive data.The key generation center generates the private and public key pairs for the web server and users,which are used to implement identity authentication and data integrity.Whenweb application code and sensitive data are transmitted between the web server and the user’s browser,a random session key is generated for encrypting the web application code and sensitive data.Meanwhile,a digital signature is generated and added to the encrypted program code and sensitive data.The security analysis shows that the proposed security scheme can ensure the confidentiality,integrity and authentication of web application code and sensitive data.展开更多
The decryption participant＇s private key share for decryption is delegated by key generation center in the threshold IBE scheme.However,a key generation center which is absolutely trustworthy does not exist.So the au...The decryption participant＇s private key share for decryption is delegated by key generation center in the threshold IBE scheme.However,a key generation center which is absolutely trustworthy does not exist.So the author presents a certificateless threshold public key encryption scheme.Collaborating with an administrator,the decryption participant generates his whole private key share for decryption in the scheme.The administrator does not know the decryption participant＇s private key share for decryption.Making use of q-SDH assumption,the author constructs a certificateless threshold public key encryption scheme.The security of the scheme is eventually reduced to the solving of Decisional Bilinear Diffie-Hellman problem.Moreover,the scheme is secure under the chosen ciphertext attack in the standard model.展开更多
Tate pairings over elliptic curves are important in cryptography since they can be. used to construct efficient identity-based cryptosystems, and their implementation dominantly determines the efficiencies of the cryp...Tate pairings over elliptic curves are important in cryptography since they can be. used to construct efficient identity-based cryptosystems, and their implementation dominantly determines the efficiencies of the cryptosystems. In this paper, the implementation of a cryptosystem is provided based on the Tate. pairing over a supersingular elliptic curve of MOV degree 3. The implementation is primarily designed to re-use low-level codes developed in implementation of usual elliptic curve cryptosystems. The paper studies how to construct the underlying ground field and its extension to accelerate the finite field arithmetic, and presents a technique to speedup the time-consuming powering in the Tate pairing algorithm.展开更多
基金Supported by the National Natural Science Foun-dation of Chinafor Distinguished Young Scholars(60225007) the Na-tional Research Fundfor the Doctoral Programof Higher Education ofChina(20020248024) the Science and Technology Research Pro-ject of Shanghai (04DZ07067)
文摘In a strong designated verifier proxy signature scheme, a proxy signer can generate proxy signature on behalf of an original signer, but only the designated verifier can verify the validity of the proxy signature. In this paper, we first define the security requirements for strong designated verifier proxy signature schemes. And then we construct an identity-based strong designated verifier proxy signature scheme. We argue that the proposed scheme satisfies all of the security requirements.
基金This work was supported by project of State Grid Shandong Electric Power Company(No.520627200001).
文摘How to protect the security of web application code and sensitive data has become one of the primary concerns in web services.In this paper,symmetric cryptosystem combined with identity-based public key cryptosystem is proposed to protect web application programs and sensitive data.The key generation center generates the private and public key pairs for the web server and users,which are used to implement identity authentication and data integrity.Whenweb application code and sensitive data are transmitted between the web server and the user’s browser,a random session key is generated for encrypting the web application code and sensitive data.Meanwhile,a digital signature is generated and added to the encrypted program code and sensitive data.The security analysis shows that the proposed security scheme can ensure the confidentiality,integrity and authentication of web application code and sensitive data.
基金Supported by the National Natural Science Foundation of China(60903175,60703048)the Natural Science Foundation of Hubei Province (2009CBD307,2008CDB352)
文摘The decryption participant＇s private key share for decryption is delegated by key generation center in the threshold IBE scheme.However,a key generation center which is absolutely trustworthy does not exist.So the author presents a certificateless threshold public key encryption scheme.Collaborating with an administrator,the decryption participant generates his whole private key share for decryption in the scheme.The administrator does not know the decryption participant＇s private key share for decryption.Making use of q-SDH assumption,the author constructs a certificateless threshold public key encryption scheme.The security of the scheme is eventually reduced to the solving of Decisional Bilinear Diffie-Hellman problem.Moreover,the scheme is secure under the chosen ciphertext attack in the standard model.
文摘Tate pairings over elliptic curves are important in cryptography since they can be. used to construct efficient identity-based cryptosystems, and their implementation dominantly determines the efficiencies of the cryptosystems. In this paper, the implementation of a cryptosystem is provided based on the Tate. pairing over a supersingular elliptic curve of MOV degree 3. The implementation is primarily designed to re-use low-level codes developed in implementation of usual elliptic curve cryptosystems. The paper studies how to construct the underlying ground field and its extension to accelerate the finite field arithmetic, and presents a technique to speedup the time-consuming powering in the Tate pairing algorithm.
