Study On Analysis, Design And Applications Of Signcryption Schemes

Authenticity and confidentiality are the main goals of information security. Signcryption fulfills both functions of digital signature and encryption in a single logical step. It is a high efficient cryptographic primitive achieving confidentiality and authenticity simultaneously. Therefore, signcryption is a core technique for information security. This dissertation mainly studies the analysis, design and applications of signcryption schemes. The results obtained are as follows.(1) The securities of some important signcryption schemes are analyzed. We point out their security weaknesses and some improvements of these schemes are given.(2) We study signcryption schemes with forward secure. As a result, two types of forward secure signcryption schemes are proposed. This enhances the security and practicability of signcryption schemes.(3) We design one type of signcryption schemes without Hash and Redundancy functions. This type signcryption scheme can avoid the threaten resulting from breaking their component parts such as Hash functions. This work somewhat expands the mold of signcryption schemes.(4) An application of a typic multi-signcryption scheme is studied. Using this multi-signcryption scheme, we propose a route discovery process protocol in Ad hoc networks and the protocol's security and efficiency are analyzed.(5) ID-based signcryption schemes and their applications are studied. An ID-based signcryption scheme and an ID-based multi-signcryption scheme using bilinear pairings are proposed. Applying these two ID-based schemes, a new secure protocol for protecting mobile agent from malevolence hosts' attacks is designed, and its security and efficiency are analyzed.(6) We apply signcryption schemes to the design of key agreement protocols. Anauthenticated key agreement protocol based on our ID-based signcryption scheme isproposed and its security, efficiency and adaptability for Ad hoc networks areanalyzed.