Secure Proxy Signature Schemes for Delegation of Signing Rights

A proxy signature scheme permits an entity to delegate its signing rights to another entity. These schemes have been suggested for use in numerous applications, particularly in distributed computing. But to date, no proxy signature schemes with guaranteed security have been proposed; no precise definitions or proofs of security have been provided for such schemes. In this paper, we formalize a notion of security for proxy signature schemes and present provably-secure schemes. We analyze the security of the well-known delegation-by-certificate scheme and show that after some slight but important modifications, the resulting scheme is secure, assuming the underlying standard signature scheme is secure. We then show that employment of the recently introduced aggregate signature schemes permits bandwidth and computational savings. Finally, we analyze the proxy signature scheme of Kim, Park and Won, which offers important performance benefits. We propose modifications to this scheme that preserve its efficiency, and yield a proxy signature scheme that is provably secure in the random-oracle model, under the discrete-logarithm assumption

Cryptanalysis of B.Lee-S.Kim-K.Kim Proxy Signature

Blind signature is the concept to ensure anonymity of e-cion. Untracebility and unlinkability are two main properties of real coin, which require mimicking electronically. Proxy signature schemes allow a proxy signer to generate a proxy signature on behalf of an original signer.All the previous proxy signature schemes are based on ElGamal-type schemes.In this paper, we propose a new proxy blind signature scheme based on an ID-based signature scheme, which uses bilinear pairings of elliptic curves or hyperelliptic curves