无线传感器网络分布式数字水印算法研究与实现
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摘要
无线传感器网络的主要任务是采集环境数据,但是由于其通常部署在敌对区域,网络信息容易遭到敌对方的恶意篡改和伪造,因此如何保证网络收集到的数据的完整性、可靠性与新鲜性是至关重要的。数字水印技术可将一些标识信息嵌入到载体数据中,伴随着载体数据变化而变化,应用系统可以根据提取出的标识信息缺损情况判断数据的完整性与可靠性,具有计算复杂度低的特性,可为无线传感器网络数据的安全性提供保障。因此,本文结合无线传感器网络节点分布式采集、处理数据等特点,着重研究了适合无线传感器网络的分布式数字水印算法与实现问题,主要工作如下：
(1)无线传感器网络中已有的数据认证机制通常需要在数据包后附加多个MAC,这种方法计算复杂、能耗大。本文基于网络分层管理的体系结构提出一种分组协商的数字水印算法。通过对传感器网络中节点密集的簇进一步分组,使组内节点以协商方式构造待嵌入的水印信息,每个节点独立地对待传输数据以取模运算方式嵌入水印。分析与实验表明该算法嵌入的水印对网内有损数据处理具有一定的鲁棒性,同时对于入侵者非法篡改数据具有一定的脆弱性,能有效鉴别采集的数据是否遭受恶意篡改或伪造。
(2)应用中一些对完整性要求非常严格的数据(如军事信息等),在认证后必须能够进行无损的恢复。本文针对数据的可恢复性要求提出无线传感器网络中基于差分扩展的可逆水印算法。算法特别针对网络部署的空间开放性和节点本身有限的防御能力等问题将整体水印分为一定数目的片段,并由各组节点进行随机化处理使所有的片段呈随机性分布,以增加共谋攻击采用比较的方式获得水印信息的难度。同时在节点和终端间用一对同步的随机序列发生器解决了对数据的新鲜性鉴别问题。
(3)设计并实现了一个基于OMNeT++仿真软件的无线传感器网络数字水印仿真系统,各节点以分组协商方式构造待嵌入的水印信息,并将感知数据转发回基站进行处理。实验显示,基站能够跟据节点所嵌入的水印对网络收集到的感知数据进行完整性与可靠性认证,保障了数据的安全性。最后本文基于TinyOS系统在Micaz节点上实现了一个无线传感器数字水印的原型系统。系统中的节点采用本文的分布式算法对采集的温度与光强数据嵌入水印,经簇头转发给汇聚节点,由网络终端上位机负责对含水印数据进行提取和认证。
To protect the reliabity, integerity and freshness of the data collected from the networks is crucial for wireless sensor network whose main task is to sense data of the circumstance,for the reason that the data probably be modified by an invader as this network is always deployed in hostile areas.Watermarks embedded into sensor datas of wireless sensor network as an identity of generator would change along with data transformation and shall be detected by an application system to determine the reliability and integrity of the data. According to the quality of distributed data sensing and processing on single nodes in wireless sensor network, this paper mainly does research on distributated watermarking algorithms and the implementations, which are suitable for wireless sensor network.The main work is as follows:
(1)Usually, the current data authentication in wireless sensor network shall append several message authentication codes to the data packet, which have a high computational complexity and enery consumption.In this paper, a negotiation-based digital watermarking for wireless sensor networks is given.Clusters with dense nodes in WSN are divided into groups,and nodes of the same group consult the watermarks that will be embedded into the sensing data. Each node embeds watermark bits into sensor data by modular operation. The analysis and experiments show that the watermarks are robust against loss data process while fragile to invalid modification by an invader, which could distinguish the false data and invalid data modification.
(2)In reality applications such as military, high constraint of data integerity are always demanded of, and the data must be recovered after security authentication, thus we propose a reversible watermarking based on difference expansion algorithm to satisfy the requirement of data recovery. Especially, several technique against the open space of the network deployment and resource constraint of single sensor node have been made;The whole watermark is split into a number of segments that shall be randomly assigned to sensor node in order to enhance the ability to resist collusion attack, which might get the watermark by comparing data. Meanwhile,the data fresh problem is resolved through a pair of synchronous random number generator kept by both sensor node and sink separately.
(3)Based on the above achievements,a watermark emulator using OMNeT++ simulation software is designed and implemented.Nodes of the same group generate watermark by negotiation, and forward sensor datas to base station for detection.The experiment shows that the watermark emulator could authenticate the integrity and reliability of data in which watermarks was embedded by sensor nodes,thus enhence the safety of data. In the end,we have implemented a watermarking prototype system in TinyOS as well.The prototype system could collect temperature and luminosity of the surroundings where sensor nodes are located.Each single node of the network could embed watermarks into its data which will be detected later by the network terminal PC,and forward data packet to base station via cluster header.
(1)无线传感器网络中已有的数据认证机制通常需要在数据包后附加多个MAC,这种方法计算复杂、能耗大。本文基于网络分层管理的体系结构提出一种分组协商的数字水印算法。通过对传感器网络中节点密集的簇进一步分组,使组内节点以协商方式构造待嵌入的水印信息,每个节点独立地对待传输数据以取模运算方式嵌入水印。分析与实验表明该算法嵌入的水印对网内有损数据处理具有一定的鲁棒性,同时对于入侵者非法篡改数据具有一定的脆弱性,能有效鉴别采集的数据是否遭受恶意篡改或伪造。
(2)应用中一些对完整性要求非常严格的数据(如军事信息等),在认证后必须能够进行无损的恢复。本文针对数据的可恢复性要求提出无线传感器网络中基于差分扩展的可逆水印算法。算法特别针对网络部署的空间开放性和节点本身有限的防御能力等问题将整体水印分为一定数目的片段,并由各组节点进行随机化处理使所有的片段呈随机性分布,以增加共谋攻击采用比较的方式获得水印信息的难度。同时在节点和终端间用一对同步的随机序列发生器解决了对数据的新鲜性鉴别问题。
(3)设计并实现了一个基于OMNeT++仿真软件的无线传感器网络数字水印仿真系统,各节点以分组协商方式构造待嵌入的水印信息,并将感知数据转发回基站进行处理。实验显示,基站能够跟据节点所嵌入的水印对网络收集到的感知数据进行完整性与可靠性认证,保障了数据的安全性。最后本文基于TinyOS系统在Micaz节点上实现了一个无线传感器数字水印的原型系统。系统中的节点采用本文的分布式算法对采集的温度与光强数据嵌入水印,经簇头转发给汇聚节点,由网络终端上位机负责对含水印数据进行提取和认证。
To protect the reliabity, integerity and freshness of the data collected from the networks is crucial for wireless sensor network whose main task is to sense data of the circumstance,for the reason that the data probably be modified by an invader as this network is always deployed in hostile areas.Watermarks embedded into sensor datas of wireless sensor network as an identity of generator would change along with data transformation and shall be detected by an application system to determine the reliability and integrity of the data. According to the quality of distributed data sensing and processing on single nodes in wireless sensor network, this paper mainly does research on distributated watermarking algorithms and the implementations, which are suitable for wireless sensor network.The main work is as follows:
(1)Usually, the current data authentication in wireless sensor network shall append several message authentication codes to the data packet, which have a high computational complexity and enery consumption.In this paper, a negotiation-based digital watermarking for wireless sensor networks is given.Clusters with dense nodes in WSN are divided into groups,and nodes of the same group consult the watermarks that will be embedded into the sensing data. Each node embeds watermark bits into sensor data by modular operation. The analysis and experiments show that the watermarks are robust against loss data process while fragile to invalid modification by an invader, which could distinguish the false data and invalid data modification.
(2)In reality applications such as military, high constraint of data integerity are always demanded of, and the data must be recovered after security authentication, thus we propose a reversible watermarking based on difference expansion algorithm to satisfy the requirement of data recovery. Especially, several technique against the open space of the network deployment and resource constraint of single sensor node have been made;The whole watermark is split into a number of segments that shall be randomly assigned to sensor node in order to enhance the ability to resist collusion attack, which might get the watermark by comparing data. Meanwhile,the data fresh problem is resolved through a pair of synchronous random number generator kept by both sensor node and sink separately.
(3)Based on the above achievements,a watermark emulator using OMNeT++ simulation software is designed and implemented.Nodes of the same group generate watermark by negotiation, and forward sensor datas to base station for detection.The experiment shows that the watermark emulator could authenticate the integrity and reliability of data in which watermarks was embedded by sensor nodes,thus enhence the safety of data. In the end,we have implemented a watermarking prototype system in TinyOS as well.The prototype system could collect temperature and luminosity of the surroundings where sensor nodes are located.Each single node of the network could embed watermarks into its data which will be detected later by the network terminal PC,and forward data packet to base station via cluster header.
引文
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[2]Chong C Y, Kumar S P. Sensor networks:Evolution, opportunities, and challenges.In:Proc of Sensor Networks and Applications.Washington:IEEE Press,2003,1247-1256
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[4]Pottie G J,Kaiser W J.Wireless integrated network sensors.Communications of the A CM,2000,43(5):51-58
[5]李建中,李金宝,石胜飞.传感器网络及其数据管理的概念,问题与进展.软件学报,2003,14(10)：1717-1727
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[7]唐勇,周明天,张欣.无线传感器网络路由协议研究进展.软件学报,2006,17(3)：410-421
[8]马华东,陶丹.多媒体传感器网络及其研究进展.软件学报,2006,17(9)：2013-2028
[9]崔莉,鞠海玲,苗勇等.无线传感器网络研究进展.计算机研究与发展,2005,42(1)：163-174
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[11]Perrig A,Szewczyk R, Wen V, et al.SPINS:Security protocols for sensor networks.Wireless Networks,2002,8(5):521-534
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[21]Tirkel A Z, Osborne C F, Hall T E.Image and watermark registration. Signal Processing,1998,66(3):373-383
[22]Nikolaidis N, Pitas I.Robust image watermarking in the spatial domain.Signal Processing,1998,66(3):385-403
[23]Swanson M D, Zhu B, Tewfik A H,et al.Robust audio watermarking using perceptual masking.Signal Processing,1998,66(3):337-355
[24]Cox I J,Kilian J,Leighton F T, et al.Secure spread spectrum watermarking for multimedia. IEEE Transaction on Image Processing,1997,6(12):1673-1687
[25]Darmstaedter V, Delaigle J F, Quisquater J J, et al.Low cost spatial watermarking.Comput&Graphics,1998,22(4):417-424
[26]Hernandez J R, Rodriguez J M,Perez-Gonzalez F. Improving the performance of spatial watermarking of images using channel coding.Signal Processing,2000, 80(7):1261-1279
[27]Nikolaidis N and Pitas I. Robust image watermarking in the spatial domain. Signal Processing,1998,66(3):385-403
[28]Langelaar G C,Lagendijk R L.Optimal differential energy watermarking of DCT encoded images and video.IEEE Transactions on Image Processing,2001, 10(1):148-158
[29]Capellini V, Barni M, Bartolini F, et al.A DCT-dormain system for robust image watermarking.Signal Processing,1998,66(5):357-372
[30]Hernahndez J R, Fernando P G. DCT-Domain Watermarking Techniques for Still Images:Detector Performance Analysis and a New Structure.IEEE Transactions on Image Processing,2000,9(1):55-68
[31]Kundur D, Hatzinakos D. A robust digital image watermarking using wavelet-based fusion.In:Proc of the 1997 International Conference on Image Processing.Piscataway:IEEE Press,1997,544-547
[32]Craver S,Yeo B L,Yeung M. Technical trials and legal tribulations. Communications of the ACM,1998,41(7):45-54
[33]Zhang W, Liu Y H,DAS S K, et al.Secure data aggregation in wireless sensor networks:A watermark based authentication supportive approach.Pervasive and Mobile Computing,2008,4(6):658-680
[34]易叶青,林亚平,彭舸等.无线传感器网络中不依赖MAC认证的虚假数据过滤算法.通信学报,2009,30(6)：53-63
[35]易叶青,林亚平,李小龙等.WSN中基于协作水印的虚假数据过滤算法.软件学报,2010,21(1)：107-118
[36]彭志娟,王汝传,王海艳.基于数字水印技术的无线传感器网络安全机制研究.南京邮电大学学报,2006,26(4)：69-73
[37]Wang H G,Peng D M,Wang W, et al.Energy-aware Adaptive Watermarking for Real-Time Image Delivery in Wireless Sensor Networks.In:Proc of 37th North American Symposium.Beijing:IEEE Press,2005,1479-1483
[38]Kleider J E,Gifford S,Chuprun S,et al.Radio frequency watermarking for OFDM wireless networks.In:Proc of Acoustic,Speech and Signal processing. Montreal.Canada:IEEE press,2004,397-400
[39]Roy S,Setia S,Jajodia S.Attack Resilient Hierarchical Data Aggregation in Sensor Networks.In:Proc of secure data aggregation and transmission. New York:ACM press,2006,71-82
[40]Wong J L,Feng J, Kirovski D,et al.Security in Sensor Networks:Watermarking Techniques.Wireless Sensor Networks.NewYork:Springer Science and Business Media,2004,305-323
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[52]Adnan M.Reversible Watermark Using the Diference Expansion of a eneralized Integer Transform.IEEE Transactions on Image Processing,2004,13(8): 1147-1156
[2]Chong C Y, Kumar S P. Sensor networks:Evolution, opportunities, and challenges.In:Proc of Sensor Networks and Applications.Washington:IEEE Press,2003,1247-1256
[3]Akyildiz I F, Su W, Sankarasubramaniam Y, et al.Wireless sensor networks:a survey. IEEE Communications Magazine,2002,40(8):102-114
[4]Pottie G J,Kaiser W J.Wireless integrated network sensors.Communications of the A CM,2000,43(5):51-58
[5]李建中,李金宝,石胜飞.传感器网络及其数据管理的概念,问题与进展.软件学报,2003,14(10)：1717-1727
[6]于海斌,曾鹏,王忠锋等.分布式无线传感器网络通信协议研究.通信学报,2004,25(10)：102-110
[7]唐勇,周明天,张欣.无线传感器网络路由协议研究进展.软件学报,2006,17(3)：410-421
[8]马华东,陶丹.多媒体传感器网络及其研究进展.软件学报,2006,17(9)：2013-2028
[9]崔莉,鞠海玲,苗勇等.无线传感器网络研究进展.计算机研究与发展,2005,42(1)：163-174
[10]孙利民,李建中,陈渝等.无线传感器网络.北京：清华大学出版社,2005,179-217
[11]Perrig A,Szewczyk R, Wen V, et al.SPINS:Security protocols for sensor networks.Wireless Networks,2002,8(5):521-534
[12]尹浩,林闯,邱锋等.数字水印技术综述.计算机研究与发展,2005,42(7)：1093-1099
[13]Dipti P M, Scott T. Spatial Domain Digital Watermarking of Multimedia Objects for Buyer Authentication.IEEE Transactions on multimedia,2004,6(1):1-15
[14]Hernandez J R, Perez-Gonzalez F. Statistical analysis of watermarking schemes for copyright protection of images.Proceedings of the IEEE,1999,87(7): 1142-1165
[15]Hernandez J R, Perez-Gonzalez F, Rodriguez J M,et al. Performance analysis of a 2-D-multipulse amplitude modulation scheme for data hiding and watermarking of still images. IEEE Journal on Selected Areas in Communications,1998,16(4):510-524
[16]Voyatzis G, Pitas I.The use of watermarks in the protection of digital multimedia products.Proceedings of the IEEE,1999,87(7):1197-1207
[17]Christine I, Edward J. Digital watermarking:Algorithms and applications. Signal Processing,2001,14(4):33-46
[18]杨义先,钮心忻.数字水印理论与技术.北京：高等教育出版社,2006,32-107
[19]Bender W, Gruhl D,Morimoto N, et al. Techniques for data hiding.IBM System Journal,1996,35(4):313-335
[20]Wolfgang R B,Delp E J. A watermark for still images.In:Proc of the 1996 International Conformation on Image Processing.Lausanne,Switzerland:IEEE press,1996,219-223
[21]Tirkel A Z, Osborne C F, Hall T E.Image and watermark registration. Signal Processing,1998,66(3):373-383
[22]Nikolaidis N, Pitas I.Robust image watermarking in the spatial domain.Signal Processing,1998,66(3):385-403
[23]Swanson M D, Zhu B, Tewfik A H,et al.Robust audio watermarking using perceptual masking.Signal Processing,1998,66(3):337-355
[24]Cox I J,Kilian J,Leighton F T, et al.Secure spread spectrum watermarking for multimedia. IEEE Transaction on Image Processing,1997,6(12):1673-1687
[25]Darmstaedter V, Delaigle J F, Quisquater J J, et al.Low cost spatial watermarking.Comput&Graphics,1998,22(4):417-424
[26]Hernandez J R, Rodriguez J M,Perez-Gonzalez F. Improving the performance of spatial watermarking of images using channel coding.Signal Processing,2000, 80(7):1261-1279
[27]Nikolaidis N and Pitas I. Robust image watermarking in the spatial domain. Signal Processing,1998,66(3):385-403
[28]Langelaar G C,Lagendijk R L.Optimal differential energy watermarking of DCT encoded images and video.IEEE Transactions on Image Processing,2001, 10(1):148-158
[29]Capellini V, Barni M, Bartolini F, et al.A DCT-dormain system for robust image watermarking.Signal Processing,1998,66(5):357-372
[30]Hernahndez J R, Fernando P G. DCT-Domain Watermarking Techniques for Still Images:Detector Performance Analysis and a New Structure.IEEE Transactions on Image Processing,2000,9(1):55-68
[31]Kundur D, Hatzinakos D. A robust digital image watermarking using wavelet-based fusion.In:Proc of the 1997 International Conference on Image Processing.Piscataway:IEEE Press,1997,544-547
[32]Craver S,Yeo B L,Yeung M. Technical trials and legal tribulations. Communications of the ACM,1998,41(7):45-54
[33]Zhang W, Liu Y H,DAS S K, et al.Secure data aggregation in wireless sensor networks:A watermark based authentication supportive approach.Pervasive and Mobile Computing,2008,4(6):658-680
[34]易叶青,林亚平,彭舸等.无线传感器网络中不依赖MAC认证的虚假数据过滤算法.通信学报,2009,30(6)：53-63
[35]易叶青,林亚平,李小龙等.WSN中基于协作水印的虚假数据过滤算法.软件学报,2010,21(1)：107-118
[36]彭志娟,王汝传,王海艳.基于数字水印技术的无线传感器网络安全机制研究.南京邮电大学学报,2006,26(4)：69-73
[37]Wang H G,Peng D M,Wang W, et al.Energy-aware Adaptive Watermarking for Real-Time Image Delivery in Wireless Sensor Networks.In:Proc of 37th North American Symposium.Beijing:IEEE Press,2005,1479-1483
[38]Kleider J E,Gifford S,Chuprun S,et al.Radio frequency watermarking for OFDM wireless networks.In:Proc of Acoustic,Speech and Signal processing. Montreal.Canada:IEEE press,2004,397-400
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