針對(duì)現(xiàn)有的(t,n)門限簽名方案中所存在的當(dāng)群內(nèi)任何t個(gè)或更多個(gè)秘密分享成員聯(lián)合攻擊，能暴露系統(tǒng)的秘密密鑰的問題，設(shè)計(jì)了一種能抵制群內(nèi)成員聯(lián)合攻擊的可證實(shí)的具有系統(tǒng)穩(wěn)定性的門限簽名方案。該方案的安全性是基于求離散對(duì)數(shù)和RSA大整數(shù)因式分解的困難，其群簽名長度和群簽名的驗(yàn)證時(shí)間只相當(dāng)于一般個(gè)人簽名。
關(guān) 鍵 詞 門限群簽名; 可驗(yàn)證性; 高效性; 離散對(duì)數(shù); 因式分解問題

Abstract Group oriented (t,n) threshold digital signature schemes have a problem in that the underlying signature schemes will be broken if any t or more shadowholders conspire together with each other,thus the group secret key will be revealed.The new scheme proposed by us can avoid the conspiracy attack.It is based on the difficulty of computing the discrete logarithm modulo for a composite number and the factorization problem of large integer.The size of the group signature and verification time of the group signature are equivalent to that of an individual signature.
Key words threshold group signature; verification; efficiency; discrete logarithm; factoring problem