Researchs On Some Key Issues Of Proxy Signature And Its Extension

In 1996, proxy signature and its efficient solution were introduced by Mambo etc., and then proxy signature schemes have enjoyed a considerable amount of interest from the cryptographic research community. New proxy signature schemes have been proposed, Furthermore, various extensions of the basic proxy signature have been considered. These include threshold proxy signatures, blind proxy signatures, proxy signatures with warrant recovery, nominative proxy signatures, one-time proxy signature, and proxy-anonymous proxy signatures, proxy multi-signature etc. Proxy signatures have found numerous practical applications, particularly in distributed computing, e-vote, e-payment, Grid computing, mobile communications etc, where delegation of rights is quite commonThis dissertation makes researches on some key issues of proxy signature schemes and its extensions. Main achievements in this paper are summarized as follows:1. Proxy Signature Scheme with Restricted Signing CapabilityThe controllability of proxy signature is got with most difficult. Atthe stage of being, the controllability of proxy signature basically controls the proxies' abilities from various qualities, but cannot solve the abuse of the signature power. In the scheme proposed in this paper, the original signer restricts the number of times that proxy signer can sign in the proxy delegation step. So we can restricts the signers' power from quantities and greatly improve the controllability of origin signers.2. Proxy Multi-Signauture Scheme With Security and EfficiencyThe modified scheme proposed in this paper, which is based on the LKK scheme, completely resolves the security problem of the original scheme and also not requires secure channel. In additon, we also improve GU et al.'s proxy multi-signature scheme. The changes aim at the problem of the attack of all original signers cooperating and requirement of secure channel. By the changes, we also improve the efficiency of the original scheme.3. Mobile Agent-based Security Scheme of Electronic TransactionsIn this paper, we analysis Hu-Yang non-designated proxy signaturescheme, and point the security problems of the scheme, and then propose a modified secure non-designated prosy signature scheme. Subsequently, we apply this scheme to mobile agent-based electronic commerce transactions. The security analysis of the proposed scheme show that it meets all security requirements we summarized, it is more practicable.4. Self-proxy Signature Scheme and its Application in the Networking NotarizationIn this paper, through analyzing the Kim et al.'s self proxy scheme, we propose a new self delegation scheme. Compared to Kim et al.'s scheme, the new scheme has more efficiency and more suits characteristics of self proxy. Applying the new scheme to the generation, issue and verification of networking notarization, we can resolve some issues of networking notarization, such as:(1) Reduce the burden of notarization authority;(2) Reduce the burden of clients.