Research On Signcryption And Key Agreement Schemes From Bilinear Pairing

With the advance of the technique about computer network, all kinds of network sevices have soaked in many aspects of people's life. Since more and more information are storaged, transmited and operated in the open network, it maybe suffer from all kinds of attacks and threats, such as wiretapping, intercept, modified forgery and replay attack. Thus information security has become one of the most important problems to be solved.Cryptographic protocol is one of the key techniques to provide authentication, confidentiality, integration and non-repudiation in the network environment, and it is the foundation for establishing the secure network environment, so it has become one of the key technology of information security. Bilinear pairings is a crucial tool for constructing the cryptographic protocols in recent years. The bilinear pairing-based cryptographic protocols not only have the advantages of higher security, shorter key size and faster implementation, but also possess many benefits that cannot be easily achieved by using other techniques. This dissertation focuses on the study of the analysis, design and applications of two types of the pairing-based cryptographic protocols including signcryption and key agreement schemes. The specific contents are as follows:(1) We study signcryption schemes for multi-domain networks. As a result, an identity-based signcryption scheme from bilinear pairing in which different domains share different system parameters is proposed. This expands the application scope of signcryption schemes. Applying this scheme, a new end-to-end and point-to-point secure scheme for protecting VoIP communication entities is proposed, The implementation reveals that our scheme meets the security and performance requirements of VoIP communications.(2) A certificate-based signcryption scheme from bilinear pairing is designed, which preserves the the advantages of signcryption scheme using traditional pubic key encryption and identity-based signcryption scheme. Thus, this type signcryption scheme has high practical value.(3) The signcryption schemes with less resource costs are studied. A certificateless short signcryption scheme and a certificateless on-line/off-line signcryption scheme from bilinear pairing are proposed. The analysis results show that our schemes excel the existing schemes in terms of the security and efficiency.(4) We present the concept called Identity-based concurrent signcryption which combines the concepts of concurrent signature and signcryption together, also we propose a concrete algorithm and a novel fair exchange protocol for physical goods exchange. This protocol provides additional information confidentiality protection compared with other protocols.(5) We study broadcast signcryption schemes. A certificateless broadcast signcryption scheme from bilinear pairing is proposed. As compared with the recently proposed broadcast signcryption schemes, our scheme has less computation overheads, satisfies register authentication, forward secrecy and eliminates the key escrow problem.(6) The security mechanisms for wireless networks are studied. A kind of authentication and key agreement mechanism for wireless networks using certificateless public key cryptography from bilinear pairing is proposed. The mechanism makes communication entities in different domains have different system parameters, satisfies the forward secrecy, key control and eliminates the key escrow problem. In terms of computation overheads, our scheme does not require expensive bilinear pairing operation on the user side, thus it is very suitable for mobile devices with limited computing capability.(7) We analyse Wang and Zhang's authentication and key agreement mechanism. We point out their security weaknesses. We propose an improved scheme that overcomes the above weaknesses. Moreover, our improved scheme enjoys less computation overheads.