流媒体系统多数据流安全的动态选择控制模型  

Selective control mechanism for multi-datastream security in streaming media system

作　　者：肖晨[1] 马世龙[1] 吕卫峰[1] 王丽丰[2] 

机构地区：[1]北京航空航天大学计算机学院,北京100191 [2]北京电子科技学院电子信息工程系,北京100070

出　　处：《北京航空航天大学学报》2008年第11期1292-1297,共6页Journal of Beijing University of Aeronautics and Astronautics

基　　金：国家973资助项目(G1999032711,2005CB32190);中央办公厅信息安全保密重点实验室基金资助项目(KYKF200702)

摘　　要：部分加密等媒体数据加密算法是保护媒体数据安全的有效方法,但用其加密流媒体系统中的多路媒体数据将使系统面临效率、规模扩展与安全性问题.为此提出基于数据安全权重的多数据流加密的动态最优选择控制模型,根据各数据流的带宽、权重等参数,为不同数据动态选择不同强度的加密方法.由于化简后的数学模型是NP难的0-1背包问题,结合实际系统特点提出基于贪婪启发思想的增量式近似算法.理论分析和实验表明该算法时间复杂度低且具有良好的近似性.最终在一个实用流媒体系统———Adm ire系统中设计实现了选择控制模型的原型子系统.Partial encryption and other media encryption schemes are effective approaches to encrypt the media data which are high volume and latency sensitive. However, use one media encryption scheme to protect all the media streams in a streaming media system will induce efficiency, sealability and security problems. To solve this problem, a security weightiness based dynamic optimal selective control mechanism for multi-datastream encryption was proposed. The idea of partial eneryption was generalized from encrypting a subset of one stream to multi-streams. It can determine the optimum eneryption algorithm with different security levels for each stream in the system, according to stream＇s bandwidth, weightiness and other parameters. Since the simplified mathematical model is 0-1 knapsack problem which is NP-hard, a greedy heuristic incremental approximate algorithm was designed. Theoretical and experimental analyses show the approximate rate and speed of the algorithm are effective enough to support real-time applications. A prototype was implemented in an actual video conferencing system： Admire.

关 键 词：流媒体系统 数据安全 部分加密 最优控制 近似算法 

分 类 号：TP309.2[自动化与计算机技术—计算机系统结构]