Abstract: Using the way of computing directly, this paper analyzes the computation complexity of the improved Py distinguish attack algorithm proposed by Crowley P. Using the concept of replacing time with space, this paper presents a new method to implement the attack which can reduce the complexity to 1/14 times of that of using the way of computing directly.

Key words: Py algorithm, distinguish attack, computational complexity

摘要： 针对Crowley P提出的一种改进的Py区分攻击算法，利用直接计算的方法分析该算法的计算复杂性。基于以空间换时间的思想提出实现该算法的一种新的方法。结果表明，该方法能有效地将该区分攻击的计算复杂性降为直接计算所需计算复杂性的1/14。

关键词: Py算法, 区分攻击, 计算复杂性

CLC Number: 

• TN918.1