语音加密算法A5的改进  

Improvement on Voice Encryption Algorithm A5

作　　者：殷满岗[1] 周建钦[1] 

机构地区：[1]杭州电子科技大学通信工程学院,浙江杭州310018

出　　处：《吉首大学学报（自然科学版）》2011年第4期42-45,共4页Journal of Jishou University(Natural Sciences Edition)

基　　金：浙江省自然科学基金资助项目(Y1100318;R1090138);国家自然科学基金委员会与中国工程物理研究院联合基金资助(10776077);上海市信息安全综合管理技术研究重点实验室开放课题(AGK2009007)

摘　　要：针对语音加密算法A5寄存器级数过短并且抗穷举攻击能力弱的特点,提出了一种简单的自同步序列密码,用于对大数据量语音信号的加密传输.短的种子密钥不能完全初始化寄存器,为了达到扩展成足够长的初始密钥的目的,设计了一种结构简单并且非线性度很高的密钥扩展算法.利用此算法可以获得随机性强的初始密钥序列.利用延时器测试算法的加密效率,证明了此算法能够安全地使用在语音加密中.The register series of voice encryption algorithm A5 are too short,and its resistance to brute-force attack is weak.So a simple self-synchronizing stream cipher is proposed for encrypting large amounts of voice data and the transmission.In order to generate the long initial key from the short seed key,which is used to initialize the register of self-synchronization,a simple but very high nonlinear key expansion algorithm is designed.A strong random initial key sequence can be obtained by using the algorithm proposed.Then,a delayer is used to test the efficiency of encryption algorithms.It proves that the algorithms can be used in voice encryption safely.

关 键 词：语音加密 自同步序列 密钥扩展 钟控停走 

分 类 号：TP309.7[自动化与计算机技术—计算机系统结构]