专利详情

专利名称	METHOD AND DEVICE FOR IMPLEMENTING STREAM CIPHER
申请号	EP20090845692	专利类型	EP
公开（公告）号	EP2442482(B1)	公开（授权）日	2016.09.14
申请（专利权）人	中国科学院信息工程研究所	发明（设计）人	FENG, DENGGUO;JIN, CHENHUI;QI, WENFENG;WU, WENLING;WANG, KUNPENG;GUAN, JIE;ZHU, XUANYONG;ZHANG, YIWEI;HU, YUPU;ZHANG, BIN;ZHANG, WENZHENG;FENG, XIUTAO;QIAN, LISONG;ZHANG, WENTAO;SUN, ZHONGHUA
主分类号	H04L9/22	IPC主分类号	H04L9/22
专利有效期	METHOD AND DEVICE FOR IMPLEMENTING STREAM CIPHER 至METHOD AND DEVICE FOR IMPLEMENTING STREAM CIPHER	法律状态
说明书摘要	The present invention discloses a method and a device for implementing stream cipher. The method includes: implementing a key expansion operation with a pre-set 128-bit initial key and 128-bit initial vector, to obtain 16 31-bit state variables; implementing N-round operations using the state variables, wherein N is a positive integer and in turn each round of operation includes: bit restructuring, nonlinear state filtering operation and variable initialization mode operation; processing the output results after the N-round operations in turn using bit restructuring, nonlinear state filtering operation and discarding the output, as well as the variable work mode operation; implementing the following steps in each clock tick and respectively in turn: bit restructuring, nonlinear state filtering operation, XOR operation, and variable work mode operations, to obtain 32-bit pseudo-random sequence. Application of the method and device described in this invention can be simple and convenient way to obtain the required pseudo-random sequence, and has a high security.