An Efficient Certificate-based Verifiable Encrypted Signature Scheme Without Pairings

Rufen Huang, Qiang Nong
2015 Open Cybernetics and Systemics Journal  
The verifiable encrypted signature is one of the basic fair exchange protocols. There are important applications, such as e-commerce and other cryptographic protocols. We incorporate the verifiable encrypted signature into the certificate-based signature to propose an efficient certificate-based verifiable encrypted signature scheme in the paper, which does not require any bilinear pairing operations. Then we analyze the scheme's security under the elliptic curve discrete logarithm problem over
more » ... a finite field. The analytic results show that our proposed scheme is proven secure, and our scheme simplifies the management of certificates and solves the problem of private key escrow. Compared with the other existing secure verifiable encrypted signature schemes, our certificate-based verifiable encrypted signature scheme provides greater efficiency and greatly reduces the cost of computation and communication, and achieves the same security level as other existing verifiable encrypted signature scheme. Keywords: Certificate-based signature, discrete logarithm problem, ECC, provably secure, random oracle model, verifiable encrypted signature. The conventional Public Key Cryptography (PKC) and PKS are generally considered to be costly to use and manage. Identity-based Public Key Cryptography (IB-PKC) and IB-PKS were introduced by Shamir [1] in 1984 to ease the certificate management of conventional PKC, and Patent US 7711113, titled "ID-based signature, encryption system and encryption method" [7] was invented, which is an ID-based encryption and signature technique according to which more efficient and higher speed processing is possible. But key escrow is IB-PKC's inherent problem. Certificateless Public Key Cryptography (CL-PKC) and CL-PKS were proposed by Al-Riyami and Paterson in 2003 [2], whose original motivation is to solve the key escrow problem in IB-PKC and to simplify the certificate management process in conventional PKC. The related patent for the application of CL-PKC was invented in 2012, which is Patent US Application 20120023336, titled "System and method for designing secure client-server communication protocols based on certificateless public key infrastructure" [8], is a system and method for facilitating secure client server communication using certificateless public key infrastructure etc. But the "trust level" [9] of CL-PKS is lower than the conventional PKS, and only reaches level 2. The Certificate-based Public Key Cryptography (CB-PKC) was introduced first by Gentry [10] in Eurocrypt'03, it is another cryptography primitive whose original motivation is the same as CL-PKC to simplify certificate's management and to eliminate key escrow problem. A CB-PKC scheme combined a PKC scheme and an IB-PKC scheme to retain their respective advantages. Soon after, some patents about CB-PKC have continued to be invented, such as Patent US 7185195, titled "Certificate based digital rights management" [11] , is a client device, in which the certificate is associated with one or more secure components, and Patent US Application 20130173914, titled "Method for Certificate-Based Authentication" [12] , is a method for certificate-based authentication. The CB-PKC is similar to CL-PKC, the CB-PKC uses a certificate to replace the partial secret key of CL-PKC, while it does not require the use of any certificates in CL-PKC. In 2003, Kang, Park and Hahn extended CB-PKC to CB-PKS [3] . A CB-PKS scheme is a compromise between IB-PKS and PKS. It consists of a certifier and users, each user generates his own An Efficient Certificate-based Verifiable Encrypted Signature Scheme The Open
doi:10.2174/1874110x01408010239 fatcat:3evvfxeuh5ekbeyfwdflfbys3e