签名算法的安全性依赖于签名密钥的安全性.密钥一旦泄漏,攻击者便可以成功伪造此前的所有签名,这会对整个签名系统造成无法弥补的损失.针对门限代理签名中的密钥泄漏问题,将前向安全引入其中,提出一种具有前向安全特性的指定验证者(t,n)门限代理签名方案.安全性分析表明,新方案真正实现了前向安全.即使当前时段所有成员的密钥被泄漏,也不会影响之前生成的签名的有效性.新方案具有指定验证者的特性,能够确保签名只被预先指定的验证人验证,可以很好地保护原始签名者的隐私.签名具有消息恢复的特性,在传输签名时不用传输明文消息本身,能够减小传输签名时的通信代价. The security of the signature algorithm depends on the security of the signature key.Once the key is leaked, the attacker can successfully forge all the previous signatures, which will cause irreparable damage to the entire signature system.Aiming at the key of the threshold proxy signature (T, n) thresholding proxy signature scheme with forward security, the security analysis shows that the new scheme realizes the forward security, even if all The member’s key is compromised and the validity of the previously generated signature is not compromised.The new scheme has the property of specifying the verifier to ensure that the signature is validated only by the pre-designated verifier and that the original signer’s privacy is well protected Signatures have the property of message recovery, which can reduce the communication cost when transmitting signatures without transmitting the plaintext message itself when transmitting signatures.