一种安全增强的基于椭圆曲线可验证门限签名方案

以Nyberg—Ruepple签名体制和Pedersen可验证秘密共享方案为基础。提出一种安全增强的基于椭圆曲线的(k，n)可验证门限签名方案．该签名方案通过周期地重分派方式在不同访问结构中共享密钥d，增强了签名密钥d的安全性，从而提高该签名方案的安全性．可以证明重分派协议重分派签名密钥后，签名密钥保持不变．与现有基于椭圆曲线的可验证门限签名方案相比．该安全增强的可验证门限签名方案不仅具有更强的安全性，而且具有入侵容忍能力．

A Security Enhancement Method of a Verifiable Threshold Signature Scheme Based on the Elliptic Curve

Proposed in this paper is an efficient (k, n) threshold digital signature scheme based on the elliptic curve. In the scheme, k out of n signers cooperate to issue a signature, while Nyberg-Ruepple digital signature scheme and Pedersen's verifiable secret sharing (VSS) are employed. This new scheme enhances the security of the existing threshold digital signature scheme by redistributing the private key d of the signature periodically into the different access structures. This design is not only more difficult for adversary to attack the threshold digital signature scheme, but also flexible for adding or deleting one or more signature participants. Assuming that secret communication between the signers is available, the security performances of the scheme are discussed. The advantage of the new scheme has capability of intrusion tolerance besides the property of verifiable partial signature which verifiable threshold signature scheme should have.