Identity Based Threshold Proxy Signature

Identity-based (ID-based) public key cryptosystem can be a good alternative for certificate-based public key setting, especially when efficient key management and moderate security are required. In a $(t,n)$ threshold proxy signature scheme, the original signer delegates the power of signing messages to a designated proxy group of $n$ members. Any $t$ or more proxy signers of the group can cooperatively issue a proxy signature on behalf of the original signer, but $t-1$ or less proxy signers cannot. In this paper, we present an ID-based threshold proxy signature scheme using bilinear pairings. We show the scheme satisfies all security requirements in the random oracle model. To the best of authors\u27 knowledge, our scheme is the first ID-based threshold proxy signature scheme

Comments on "A practical (t, n) threshold proxy signature scheme based on the RSA cryptosystem"

In a (t, n) proxy signature scheme, the original signer can delegate his/her signing capability to n proxy signers such that any t or more proxy singers can sign messages on behalf of the former, but t 1 or less of them cannot do the same thing

A verifiable secret sharing scheme based on the chinese remainder theorem

In this paper, we investigate how to achieve verifiable secret sharing (VSS) schemes by using the Chinese Remainder Theorem (CRT). We first show that two schemes proposed earlier are not secure by an attack where the dealer is able to distribute inconsistent shares to the users. Then we propose a new VSS scheme based on the CRT and prove its security. Using the proposed VSS scheme, we develop a joint random secret sharing (JRSS) protocol, which, to the best of our knowledge, is the first JRSS protocol based on the CRT. © 2008 Springer Berlin Heidelberg

Secret Sharing Extensions based on the Chinese Remainder Theorem

In this paper, we investigate how to achieve verifiable secret sharing (VSS) schemes by using the Chinese Remainder Theorem (CRT). We first show that two schemes proposed earlier are not secure from an attack where the dealer is able to distribute inconsistent shares to the users. Then we propose a new VSS scheme based on the CRT and prove its security. Using the proposed VSS scheme, we develop joint random secret sharing~(JRSS) and proactive SSS protocols, which, to the best of our knowledge, are the first secure protocols of their kind based on the CRT