基于块内频数检测法对RC4算法产生的伪随机序列检测

The Detection of Pseudo-Random Sequence Generated by RC4 Algorithm Based on Frequency Test within a Block

摘要: 序列密码算法的安全性主要取决于算法所产生的伪随机序列的随机性。NIST给出16种伪随机序列检测方法，但它们的适用范围是对选定的一段序列进行检测。如何对大量数据段随机性进行检测还需要系统化探讨。本文结合NIST的伪随机序列检测法辅以可视化方法，并对RC4算法产生的伪随机序列进行随机性检测。通过改变测量参数使可视化的结果更为丰富。通过比较分析，观察到使用不同的密钥长度所得到的图像结果不同，密钥越长特征图像的点聚集程度越高。

Abstract: The security of stream cipher mainly depends on its randomness of pseudo-random sequence. NIST has provided 16 methods for pseudo-random sequence detection, however they are only capable of detecting one selected segment. Hence, the randomness testing method for large numbers of segments needs further systematic research. This paper discussed the detection of pseudo- random sequence generated by the RC4 algorithm. The detection was achieved by combining the NIST detection methods and visual methods. The visualization results became more abundant by changing the parameters. The research result shows that using different key lengths will result in different results and that longer key length will lead to more aggregated image.