security in wireless ad hoc and sensor...
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Security in WirelessAd Hoc and SensorNetworks
Erdal Çayırcı
NATO Joint Warfare Centre, Norway
Chunming Rong
University of Stavanger, Norway
A John Wiley and Sons, Ltd, Publication
Security in Wireless Ad Hocand Sensor Networks
Security in WirelessAd Hoc and SensorNetworks
Erdal Çayırcı
NATO Joint Warfare Centre, Norway
Chunming Rong
University of Stavanger, Norway
A John Wiley and Sons, Ltd, Publication
This edition first published 2009c© 2009 John Wiley & Sons Ltd.
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Library of Congress Cataloging-in-Publication Data
Çayırcı, E. (Erdal)Security in wireless ad hoc and sensor networks / Erdal Çayırcı, Chunming Rong.
p. cm.Includes bibliographical references and index.ISBN 978-0-470-02748-6 (cloth)1. Ad hoc networks (Computer networks)—Security measures. 2. Ad hoc networks(Computer networks)—Security measures. I. Rong, Chunming. II. Title.TK5105.59.C387 2009005.8—dc22
2008041824
A catalogue record for this book is available from the British Library.
ISBN 978-0-470-02748-6 (H/B)
Set in 10/12pt Times by Integra Software Services Pvt. Ltd, Pondicherry, IndiaPrinted in Great Britain by CPI Antony Rowe, Chippenham, England
To Tülin and ErtugErdal Çayırcı
To Zhihua and HelenaChunming Rong
Contents
About the Authors xiii
Preface xv
Acknowledgements xvii
List of Acronyms xix
Part One Wireless Ad Hoc, Sensor and Mesh Networking 1
1 Introduction 31.1 Information Security 4
1.1.1 Computer Security 41.1.2 Communications Security 5
1.2 Scope of the Book 51.3 Structure of the Book 61.4 Electronic Resources for the Book 71.5 Review Questions 7
2 Wireless Ad Hoc, Sensor and Mesh Networks 92.1 Ad Hoc Networks and Applications 10
2.1.1 Application Examples 102.1.2 Challenges 11
2.2 Sensor and Actuator Networks 132.2.1 Application Examples 142.2.2 Challenges 15
2.3 Mesh Networks 172.3.1 Application Examples 182.3.2 Challenges 19
2.4 Tactical Communications and Networks 192.4.1 Blue Force Tracking System 22
2.5 Factors Influencing the Design of Wireless Ad Hoc, Sensor and MeshNetworks 232.5.1 Wireless Medium 242.5.2 Networking Regime 25
viii Contents
2.5.3 Nature of Traffic 262.5.4 Quality of Service Requirements 262.5.5 Mobility 262.5.6 Fault Tolerance 272.5.7 Operating Environment 272.5.8 Power Efficiency Requirements 272.5.9 Scalability 272.5.10 Hardware Requirements and Production Cost 27
2.6 Review Questions 28
3 The Wireless Medium 293.1 Wireless Channel Fundamentals and Security 29
3.1.1 Capacity 313.1.2 Electromagnetic Spectrum 323.1.3 Path Loss and Attenuation 353.1.4 Other Transmission Impairments and Jamming 363.1.5 Modulation and Demodulation 383.1.6 Manchester Encoding 413.1.7 Multiplexing and Duplexing 42
3.2 Advanced Radio Technologies 433.2.1 Directional and Smart Antennas 433.2.2 Software Radios 443.2.3 Cognitive Radios 443.2.4 Multiradio/Multichannel Systems 453.2.5 MIMO Systems 45
3.3 Review Questions 45
4 Medium Access and Error Control 474.1 Medium Access Control 47
4.1.1 Generic MAC Protocols 474.1.2 MAC Protocols for Wireless Ad Hoc, Sensor and Mesh
Networks 514.2 Error Control 53
4.2.1 Error Correction 544.2.2 Error Detection 56
4.3 Wireless Metropolitan Area Networks 584.3.1 IEEE 802.16 584.3.2 WiMAX 58
4.4 Wireless Local Area Networks 594.4.1 IEEE 802.11 594.4.2 Wi-Fi 60
4.5 Wireless Personal Area Networks 604.5.1 IEEE 802.15.1 604.5.2 Bluetooth 614.5.3 IEEE 802.15.4 62
Contents ix
4.5.4 ZigBee 624.5.5 WiMedia 63
4.6 Review Questions 64
5 Routing 655.1 Internet Protocol and Mobile IP 65
5.1.1 IPv4, IPv6 and Security in IP 655.1.2 Distance Vector and Link State Algorithms 685.1.3 Internetworking 705.1.4 Multicasting, Geocasting, Anycasting and
Broadcasting 715.1.5 Mobile IP 71
5.2 Routing in Wireless Ad Hoc Networks 725.2.1 Flooding and Gossiping 735.2.2 Ad Hoc On-demand Distance Vector Routing (AODV) 735.2.3 Dynamic Source Routing 74
5.3 Routing in Wireless Sensor and Actuator Networks 755.3.1 Directed Diffusion 755.3.2 Sensor Protocols for Information via Negotiation
(SPIN) 765.3.3 Low-Energy Adaptive Clustering Hierarchy
(LEACH) 765.3.4 Power-Aware Many-to-Many Routing (PAMR) 77
5.4 Review Questions 79
6 Reliability, Flow and Congestion Control 816.1 Reliability 81
6.1.1 Non-Acknowledgement-Based Schemes 836.1.2 Acknowledgement-Based Schemes 84
6.2 Flow and Congestion Control 856.3 Review Questions 88
7 Other Challenges and Security Aspects 897.1 Localization and Positioning 897.2 Time Synchronization 937.3 Addressing 957.4 Data Aggregation and Fusion 967.5 Data Querying 97
7.5.1 Database Approach 977.5.2 Task Sets 997.5.3 Other Data-Querying Schemes 99
7.6 Coverage 1007.7 Mobility Management 1017.8 Cross-layer Design 1027.9 Review Questions 103
x Contents
Part Two Security in Wireless Ad Hoc, Sensor and Mesh Networking 105
8 Security Attacks in Ad Hoc, Sensor and Mesh Networks 1078.1 Security Attacks 107
8.1.1 Passive Attacks 1078.1.2 Active Attacks 109
8.2 Attackers 1178.3 Security Goals 1198.4 Review Questions 119
9 Cryptography 1219.1 Symmetric Encryption 1219.2 Asymmetric Encryption 1279.3 Hash Functions and Message Authentication Code 1319.4 Cascading Hashing 136
9.4.1 Hash Chains 1379.4.2 Hash Trees 1379.4.3 TESLA 138
9.5 Review Questions 140
10 Challenges and Solutions: Basic Issues 14310.1 Bootstrapping Security in Ad Hoc Networks 14410.2 Bootstrapping Security in Sensor Networks 14510.3 Key Distribution, Exchange and Management 146
10.3.1 Standards 14710.3.2 Classification of Key Management Schemes 14710.3.3 Contributory Schemes 14810.3.4 Distributive Schemes 153
10.4 Authentication Issues 17110.5 Integrity 17110.6 Review Questions 172
11 Challenges and Solutions: Protection 17311.1 Privacy and Anonymity 17311.2 Intrusion Detection 174
11.2.1 Architectures for IDS in Wireless Ad Hoc Networks 17511.3 Defense Against Traffic Analysis 17711.4 Access Control and Secure Human–Computer Interaction 17711.5 Software-Based Anti-Tamper Techniques 179
11.5.1 Encryption Wrappers 18011.5.2 Code Obfuscation 18111.5.3 Software Watermarking and Fingerprinting 18111.5.4 Guarding 182
11.6 Tamper Resilience: Hardware Protection 18311.7 Availability and Plausibility 18411.8 Review Questions 185
Contents xi
12 Secure Routing 18712.1 Defense Against Security Attacks in Ad Hoc Routing 187
12.1.1 Techniques Against Wormhole Attacks 18812.1.2 Techniques Against Sybil Attacks 18912.1.3 Techniques Against Selective Forwarding 18912.1.4 Secure Routing in Sensor Networks 19012.1.5 Routing Schemes That Enhance Security 191
12.2 Secure Ad Hoc Routing Protocols 19212.2.1 Intrusion-Tolerant Routing in Wireless Sensor Networks
(INSENS) 19312.2.2 Authenticated Routing for Ad Hoc Networking (ARAN) 19512.2.3 On-Demand Secure Ad Hoc Routing (ARIADNE) 19712.2.4 Watchdog Pathrater 19912.2.5 Secure Ad Hoc On-Demand Distance Vector (SAODV) 19912.2.6 Secure Link State Routing Protocol (SLSP) 200
12.3 Further Reading 20112.4 Review Questions 202
13 Specific Challenges and Solutions 20313.1 SPINS: Security Protocols for Sensor Networks 203
13.1.1 SNEP 20413.1.2 μTESLA 205
13.2 Quarantine Region Scheme for Spam Attacks 20513.3 Secure Charging and Rewarding Scheme 209
13.3.1 Establishing a Session 21013.3.2 Packet Delivery 21113.3.3 Acknowledging Delivery 21213.3.4 Terminating a Session 212
13.4 Secure Node Localization 21313.4.1 Detection of Malicious Beacon Nodes and Replayed Beacon
Signals 21313.4.2 Attack-Resistant Location Estimation 215
13.5 Secure Time Synchronization 21613.6 Secure Event and Event Boundary Detection 217
13.6.1 Stage 1: Detection of Faulty Nodes 21713.6.2 Stage 2: Detection of Event Boundary Nodes 21913.6.3 Stage 3: Improvement of Event Boundary Node
Detection 22013.7 Review Questions 220
14 Information Operations and Electronic Warfare 22114.1 Electronic Support 22314.2 Electronic Attack 22414.3 Electronic Protection 22514.4 Review Questions 225
xii Contents
15 Standards 22715.1 X.800 and RFC 2828 227
15.1.1 Security Threats and Attacks 22715.1.2 Security Services 22815.1.3 Security Mechanisms 23015.1.4 Relationships between Security Services and Mechanisms 23115.1.5 Placements of Security Services and Mechanisms 231
15.2 Wired Equivalent Privacy (WEP) 23115.2.1 How Does WEP Work? 23115.2.2 WEP Weaknesses 236
15.3 Wi-Fi Protected Access (WPA) 23915.3.1 How Does WPA Work? 23915.3.2 WEP and WPA Comparison 24215.3.3 WPA2 242
References 245
Index 253
About the Authors
Erdal Çayırcı graduated from the Army Academy in 1986 and from the Royal MilitaryAcademy, Sandhurst in 1989. He received his MS degree from the Middle East Techni-cal University and a PhD from Bogazici University both in computer engineering in 1995
and 2000, respectively. He retired from the army whenhe was a colonel in 2005. He was an Associate Pro-fessor at Istanbul Technical University, Yeditepe Uni-versity and the Naval Sciences and Engineering Insti-tute between 2001 and 2005. Also in 2001, he wasa visiting researcher for the Broadband and WirelessNetworking Laboratory and a visiting lecturer at theSchool of Electrical and Computer Engineering, Geor-gia Institute of Technology. He is currently Chief, CAXSupport Branch in NATO’s Joint Warfare Center in Sta-vanger, Norway, and also a professor in the Electricaland Computer Engineering Department of the Univer-sity of Stavanger. His research interests include mili-tary constructive simulation, sensor networks, mobilecommunications and tactical communications.
Professor Çayırcı has acted as an editor of the jour-nals IEEE Transactions on Mobile Computing, Ad HocNetworks and Wireless Networks, and has guest edited
four special issues of Computer Networks, Ad Hoc Networks and Special Topics in MobileNetworking and Applications (MONET).
He received the 2002 IEEE Communications Society Best Tutorial Paper Award for hispaper entitled ‘A Survey on Sensor Networks’ published in the IEEE Communications Maga-zine in August 2002, the Fikri Gayret Award from the Turkish Chief of General Staff in 2003,the Innovation of the Year Award from the Turkish Navy in 2005 and the Excellence Awardin ITEC in 2006.
xiv About the Authors
Chunming Rong received his bachelors, masters and PhD degrees in Computer Science fromthe University of Bergen in Norway in 1993, 1995 and 1998, respectively. In 1995–1998, hewas a research fellow at the University of Bergen. In 2001–2003, he was a post-doctoralresearcher funded by Simula Research Laboratory. Currently, he is a Professor and chair ofthe computer science section at the University of Stavanger. He has also served as an adjunctProfessor at the University Graduate Centre, University of Oslo, since 2005.
Professor Rong was given the ConocoPhilips Communica-tion Award (Norway) in 2007. His paper ‘New Infinite Familiesof 3-Designs from Preparata Codes over Z4’ was awardedEditor’s Choice in Discrete Mathematics in 1999.
He is an associate editor of the International Journal ofComputer Science & Applications (IJCSA) and served on theeditorial board of the International Journal of Mobile Com-munications (IJMC) between 2003 and 2006. For the IEEEInternational Symposium on Security in Networks and Dis-tributed Systems (SSNDS), he was program chair in 2007 inCanada and general chair in 2008. For the International Con-ference on Autonomic and Trusted Computing (ATC), he wasaward chair in 2007 in Hong Kong and general chair in 2008 in
Norway. For the International Conference on Ubiquitous Intelligence and Computing (UIC),he was general chair in 2008 in Norway.
Professor Rong was chairman of the board of the Foundation of the Norwegian ComputerScience Conference (NIK) from 2005–2007, a board member of the Norwegian InformationSecurity Network (NISNet) from 2007–2011 and a member of the Norwegian InformaticsCouncil (Nasjonalt fagråd for informatikk). He has also been a member of the board for the‘ICT Security and Vulnerability (IKT-SoS)’ program at the Research Council of Norway. Healso currently serves in the workgroup for Information Security in Integrated Operation at theNorwegian Oil Industry Association (OLF).
As project manager, he has received grants from the Research Council of Norway forthe projects ‘Integration of Data Processing in Oil and Gas Drilling and Completion’ for2008–2010, ‘Secure and Reliable Wireless and Ad Hoc Communications (SWACOM)’for 2006–2009 and ‘Integrated IP-based Services for Smart Home Environment (IS-Home)’for 2007–2010. The Norwegian Information Security Network (NISNet) also receives annualfunding from the Research Council of Norway.
His research interests include computer and network security, wireless communications,cryptography, identity management, electronic payment, coding theory and semantic webtechnology.
Preface
Ad hoc networks formed by randomly deployed self-organizing wireless nodes have a widerange of applications, such as tactical communications, disaster relief operations and tempo-rary networking in sparsely populated areas, and therefore they have been studied extensivelyfor two decades. More recently, sensor networks have attracted interest from the researchcommunity and industry. They are more energy constrained and scalable ad hoc networks.Another form of ad hoc network, namely mesh networks, is aimed at application areas suchas infrastructureless network scenarios for developing regions, low-cost multihop wirelessbackhaul connections and community wireless networks. Characteristics such as wirelessaccess, mobility, rapid and random deployment make these kinds of network a very chal-lenging field for security. Security is also a key issue in making many ad hoc applicationscenarios practical. Although security for these networks has been studied extensively formore than a decade, there are still many challenges waiting for better solutions. Therefore,many researchers and engineers from both academia and industry continue working on thistopic.
The book is designed for a 14–18 week (three hours a week) graduate course incomputer engineering, communications engineering, electrical engineering or computerscience. Prerequisite knowledge on computer networking is required. The book isself-contained with regard to wireless ad hoc networking issues and introduces the security-related aspects of wireless ad hoc, sensor and mesh networks, providing advanced infor-mation on security issues for this domain. The book may also be used as a referencework and readers are also likely to include engineers, either from networking or securityfields, in industry or the military, who wish to perform protocol, network and secu-rity system design and implementation tasks for wireless ad hoc, sensor and meshnetworks.
The book has two parts. The first introduces fundamentals and key issues related to wirelessad hoc networking. In this part, security-related issues – the issues referred to in the secondpart – are emphasized. In the second part, security attacks and counter measures in wirelessad hoc, sensor and mesh networks are elaborated upon. There is also a very short chapterabout information operations and electronic warfare (EW) where the related terminology isintroduced. Available standards about the related topics are also briefly presented in the lastchapter.
Acknowledgements
We would like to thank our PhD students Dr Turgay Karlidere, Yan Liang and Son ThanhNguyen. Turgay contributed Chapter 4 about Medium Access Control and provided us withthe sections about the standards in that chapter. Son is the author of Chapter 15, which is aboutthe standards on data security. Yan helped us edit two chapters.
Section 10.3 was adapted from Hegland et al. (2006), a paper we co-authored. We wouldlike to thank our fellow authors of this paper, A.M. Hegland, E. Winjum, S.F. Mjølsnes,Ø Kure and P. Spilling, for letting us include the paper in this book.
List of Acronyms
AAA Authentication authorization accountingACQUIRE Active query forwarding in sensor networksADC Analog-to-digital conversionAES Advanced encryption standardAH Authentication headerAKA Auxiliary key agreementAM Access meshAOA Angle of arrivalAODV Ad hoc on-demand distance vector routingARAN Authenticated routing for ad hoc networkingARIADNE On-demand secure ad hoc routing
BACNet Building automation and control networkBAN Body area networkBEC Backward error correctionBGP Border gateway protocolBM Backbone meshBWA Broadband wireless access
C2 Command and controlC4ISR Command, control, communications, computer, intelligence, surveillance,
reconnaissanceC4ISRT Command, control, communications, computer, intelligence, surveillance,
reconnaissance, targetingCA Certificate authorityCA Collision avoidanceCBRN Chemical, biological, radiological and nuclearCCMP Counter mode with cipher block chaining message authentication code
protocolCD Collision detectionCDMA Code division multiple accessCOMINT Communications intelligenceCRC Cyclic redundancy checkCRL Certificate revocation listCRS Charging and rewarding scheme
xx List of Acronyms
CSMA Carrier sense multiple accessCTS Clear to send
DADMA Data aggregation and dilution by modulus addressingDCF Distributed coordination functionDCMD Detecting and correcting malicious dataDES Data encryption standardDISN Defense information systemDLL Data link layerDoS Denial of serviceDS Direct sequenceDSR Dynamic source routing
EAP Extensible authentication protocolECM Electronic counter measureEGP Exterior gateway protocolELINT Electronic intelligenceEMP Electromagnetic pulseEPM Electronic protection measureESM Electronic support measureESP Encapsulated security payloadESRT Event-to-sink reliable transportEW Electronic warfare
FDD Frequency division duplexingFDM Frequency division multiplexingFDMA Frequency division multiple accessFEC Forward error controlFH Frequency hopping
GPS Global positioning system
HCI Human–computer interactionHMAC Hash message authentication code
IBC Identity-based cryptographyIBE Identity-based encryptionICMP Internet control message protocolIDS Intrusion detection systemIEEE International Electrical and Electronics EngineersIF Intermediate frequencyIGP Interior gateway protocolIHL IP header lengthIKA Initial key agreementINSENS Intrusion-tolerant routing in wireless sensor networksIP Internet protocol
List of Acronyms xxi
IrDA Infrared data associationIS–IS Intermediate system–intermediate systemISM Industrial, scientific and medicalIV Initialization vector
LA Location areaLAS Local area subsystemLDAP Lightweight directory access protocolLEACH Low-energy adaptive clustering hierarchy
MAC Medium access controlMAC Message authentication codeMACA Multiple access with collision avoidanceMACAW Multiple access with collision avoidance, wirelessMARQ Mobility-assisted resolution of queriesMD Message digestMIC Message integrity codeMIMO Multiple input, multiple outputMMSE Minimum mean square estimationMPDU MAC protocol data unitMR Mobile radioMS Mobile subsystemMT Mobile terminal
NATO North Atlantic Treaty OrganizationNAV Network allocation vector
OSI Open system interconnectionOSPF Open shortest path first
PAMR Power-aware many-to-many routingPC Personal computerPCF Point coordination functionPCM Pulse code modulationPDA Personal digital assistantPKC Public key cryptographyPKG Private key generatorPKI Public key infrastructurePRMA Packet reservation multiple accessPSFQ Pump slowly, fetch quicklyPSK Preshared key
QAM Quadrature amplitude modulationQOS Quality of serviceQPSK Quadrature phase shift keyingQRS Quarantine region scheme
xxii List of Acronyms
RADIUS Remote authentication dial in user serviceRAP Radio access pointRBS Reference broadcast synchronizationsRC Rivest cipherRIP Routing information protocolRMST Reliable multisegment transportRSA Ron Rivest, Adi Shamir, Len AdlemanRSN Robust security networkRSS Received signal strengthRTS Request to send
SA Security associationSAODV Secure ad hoc on-demand distance vectorSHA Secure hash algorithmSIGINT Signal intelligenceSLSP Secure link state routing protocolSMCS System management and control subsystemSN Sequence numberSNDV Sensor network database viewSNEP Sensor network encryption protocolSNR Signal-to-noise ratioSPAAR Secure position-aided ad hoc routingSPI Sequence parameter indexSPIN Sensor protocols for information via negotiationSPINS Security protocols for sensor networksSOHO Small office, home officeSQTL Sensor query and tasking language
TACOMS Post-2000 tactical communicationsTCP Transmission control protocolTDD Time division duplexingTDM Time division multiplexingTDMA Time division multiple accessTDOA Time difference of arrivalTESLA Timed efficient stream loss-tolerant authenticationTKIP Temporal key integrity protocolTOA Time of arrivalTPSN Timing-sync protocol for sensor networksTRANS Trust routing for location-aware sensor networks
WAS Wide area subsystemWASM Wireless ad hoc, sensor and mesh networkWEP Wired equivalent privacyWi-Fi Wireless fidelityWiMAX Worldwide interoperability for microwave access
List of Acronyms xxiii
WLAN Wireless local area networkWMAN Wireless Metropolitan Area NetworksWMN Wireless mesh networkWPA Wi-Fi protected accessWPAN Wireless personal area networkWSAN Wireless sensor and actuator network
Part OneWireless Ad Hoc,Sensor and MeshNetworking
1Introduction
Although the wireless medium has limited spectrum and additional constraints whencompared to guided media, it provides the only means of mobile communication. In addition,more effective usage of the limited spectrum and advanced physical/data link layer protocolsenable broadband communications and integrated services over the limited wireless spectrum.Moreover, random and rapid deployment of a large number of tetherless nodes is possiblethrough wireless ad hoc networking, which is a technology with a wide range of applicationssuch as tactical communications, disaster relief operations and temporary networking in areasthat are not densely populated. As a result, the use of wireless ad hoc networking has becomepervasive. However, wireless ad hoc networking also introduces additional security challengeson top of those that exist for tethered networking:
• the wireless broadcast medium is easier to tap than guided media;• the wireless medium has limited capacity and therefore requires more efficient schemes
with less overhead;• the self-forming, self-organization and self-healing algorithms required for ad hoc network-
ing, and the schemes that tackle challenges such as hidden and exposed terminals, may betargeted to design sophisticated security attacks;
• the wireless medium is more susceptible to jamming and other denial-of-service attacks.
Wireless sensor and actuator networks (WSANs) are based on the random deployment ofa large number of tiny sensor nodes and actuators into or very close to the phenomenon tobe observed. They facilitate many application areas such as tactical surveillance by militaryunattended sensor networks, elderly and patient monitoring by body area networks (BANs)and building automation by building automation and control networks (BACnets). They are,in essence, ad hoc networks with additional and more stringent constraints. They need tobe more energy efficient and scalable than conventional ad hoc networks, which exacerbatesthe security challenges. The security schemes for WSANs should require less computationalpower and memory because sensor nodes are tiny and have more limited capacity than thetypical ad hoc network nodes such as a personal digital assistant (PDA) or a laptop computer.
Security in Wireless Ad Hoc and Sensor Networks Erdal Çayırcı and Chunming Rongc© 2009 John Wiley & Sons, Ltd