标准模型下非基于双线性对的非交互门限密钥封装机制

现有的高安全门限密码方案都是基于双线性配对实现的，由于双线性对的计算需要耗费大量的资源，这些方案在资源受限的环境下很不实用。因此，构造非基于双线性对密码方案是一件非常有意义的工作。带符号的二次剩余类群具有同双线性对类似的优良性质，可以用来构造门限密码方案。在带符号的二次剩余类群中，利用投影公钥技术，构造了一个非交互的门限密钥封装机制。该方案在因子分解困难问题假设下，具有自适用选择密文攻击安全性。由于避免了耗时的双线性对运算，方案具有较高的效率，可应用于资源受限的网络环境中。

The Irreciprocal Threshold Key Encapsulation Mechanism on Standard Model without Pairings

The existing threshold cryptology schemes are based ar pairings. But its inefficient computing is the main obstacle attractive and significantly worthwhile exploring aspect to on special characters of bilinein its applications. So it is an construct cryptographic algorithms without pairings. The group of signed quadratic residues has the same nice property as pairings which can be used to construct threshold cryptology schemes. Using the project ing publickey technology in the group of signed quadratic residues, we construct an irrecip rocal threshold key encapsulation mechanism on standard model with IND-CCA security. It has high efficiency for avoiding of using time-consuming parings computation, and can be used in resource-restricted condi