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Research Direction Introduction. Advisor: Professor Frank Y.S. Lin Present by Hubert J.W. Wang. Outline. Introduction Motivation Problem Description. Introduction. Background. The rapid advancement of wireless technologies has enabled a broad class of new applications.
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Research Direction Introduction Advisor: Professor Frank Y.S. Lin Present by Hubert J.W. Wang
NTU OPLab Outline • Introduction • Motivation • Problem Description
NTU OPLab Background • The rapid advancement of wireless technologies has enabled a broad class of new applications. • Some of the applications are safety-critical or life-critical such as: • Patient tracking • Traffic monitoring • Emergency rescue and recovery • Etc. • Availability has became a critical issue in wireless network.
NTU OPLab Jamming attack • Definitions • Jamming is any attack to deny service to legitimate users by generating noise or fake protocol packets or legitimate packets but with spurious timing.[1] • Jamming refers to blocking of a communication channel with the intent of preventing the flow of any information.[2] • Jamming attacks exploit the shared nature of the wireless medium in order to prevent devices from communicating or receiving.[4] • ….
NTU OPLab Jamming attack(cont’) • Nature of wireless networks. • Countermeasures • Mitigation • Prevention
NTU OPLab Wireless Mesh Network • A WMN is dynamically self-organized and self-configured, with the nodes in the network automatically establishing and maintaining mesh connectivity among themselves. • Wireless Mesh Networks(WMNs) consist of : • Mesh routers • Mesh clients • The integration of WMNs with other networks can be accomplished through the gateway and bridging functions in the mesh router.
NTU OPLab Wireless Mesh Network(cont’) • Architectures • Infrastructure/Backbone WMNs
NTU OPLab Wireless Mesh Network(cont’) • Architectures • Client WMNs
NTU OPLab Wireless Mesh Network(cont’) • Architectures • Hybrid WMNs
NTU OPLab Wireless Mesh Network(cont’) • Characteristics • Multi-hop wireless network • Extend the overage range with out sacrificing the channel capacity • Provide non-line-of-sight(NLOS) connectivity among the users with out direct line-of-sight links. • Multiple radios • Integration • Mobility
NTU OPLab Literature Survey – Jamming Attack • [4]Jamming sensor networks: attack and defense strategies • W. Xu, et al., Network, IEEE, vol. 20, pp. 41-47, 2006 • Models of jammers: • Constant jammer • Deceptive jammer • Random jammer • Reactive jammer • Detection Strategies: • PDR • Carrier sensing time • Signal strength
NTU OPLab Literature Survey – Countermeasures • [2]Using honeynodes for defense against jamming attacks in wireless infrastructure-based networks • S. Misra, et al., Computers & Electrical Engineering, vol. 36, pp. 367-382, 2010 • Mitigation techniques • Channel Surfing • Spatial Retreats • Using Wormholes • Mapping jammed regions • Spread Spectrum Techniques
NTU OPLab Literature Survey – Countermeasures(cont’) • The general approaches used for tackling jamming attacks consist of the following steps: • Attack detection • Attack mitigation • Attack prevention • Using honeynodes to prevent jamming attack from affecting the communication channel: • Sending fake traffic on a nearby channel
NTU OPLab Literature Survey – Countermeasures(cont’) Jammer 1 2400 MHz Honeynode Run 2405MHz Base Station Hop Jammer 2 Jamming 2430 MHz Base Station
NTU OPLab Literature Survey – Countermeasures(cont’) 2400 MHz Honeynode Jammer Jamming 2405 MHz Base Station Random Scan 2420 MHz Honeynode Jammer 2425 MHz Base Station Jamming
NTU OPLab Literature Survey – Jammer localization • Three challenges of jammer localization • Jammers will not comply with localization protocols.[6] • Require special infrastructure(e.g. ultrasound, infrared or laser infrastructures).[5-7] • Jamming has disturbed network communication.[6] • Unable to transmit the localization info out or the jamming area. • Should not require extensive communication among network nodes.
NTU OPLab Literature Survey – Jammer localization(cont’) • [5]Lightweight Jammer Localization in Wireless Networks: System Design and Implementation • K. Pelechrinis, et al., Global Telecommunications Conference, 2009. GLOBECOM 2009. IEEE, 2009, pp. 1-6. • Simple localization method which relies on PDR • Distributed
NTU OPLab Literature Survey – Jammer localization(cont’)
NTU OPLab Literature Survey – Jammer localization(cont’) • [6]Localizing jammers in wireless networks • H. Liu, et al., IEEE International Conference on, 2009, pp. 1-6 • Existing range-free techniques • Centroid Localization(CL) • Weighted Centroid Localization(WCL) • The accuracy of those method is extremely sensitive to node densities.
NTU OPLab Literature Survey – Jammer localization(cont’) • Virtual Force Iterative Localization(VFIF) • Use CL to perform initial position • Re-estimate the location until the estimated jammer’s position is closed to the real location • Termination • When the jammed region contains all the jammed nodes and • all boundary nodes falls out of the region. • Iteration • The jammed nodes will pull the jammed region toward themselves, • while the boundary nodes will push the jammed region away from them
NTU OPLab Literature Survey – Jammer localization(cont’)
NTU OPLab Literature Survey – Jammer localization(cont’) • Pull and Push function
NTU OPLab Literature Survey – Jammer localization(cont’)
NTU OPLab Literature Survey – Jammer localization(cont’) • [7]Wireless Jamming Localization by Exploiting Nodes’ Hearing Ranges • Z. Liu, et al., Distributed Computing in Sensor Systems. vol. 6131,2010, pp. 348-361 • Hearing-range-based localization scheme • A jammer may reduce the size of a node’s hearing range
NTU OPLab Literature Survey – Jammer localization(cont’) • The effect of Jamming on the Communication Range
NTU OPLab Literature Survey – Jammer localization(cont’) • The effect of Jamming on Network Topology
NTU OPLab Literature Survey – Jammer localization(cont’) • Jammer Localization Algorithm where • is the hearing range of node A
NTU OPLab Literature Survey – Jammer localization(cont’) • Estimating the hearing range • Average of: • The location of the furthest remaining neighbor(lower bound) • The location of the nearest lost neighbor(upper bound) • Estimation error between:
NTU OPLab Literature Survey – Jammer localization(cont’) • The nodes that can contribute to the jamming localization have to satisfy the following requirements: • They have a reduced hearing range. • The new hearing range under jamming attack can be estimated. • They are able to transmit the new hearing range out of the jammed range.
NTU OPLab Problem Description • Problem • Jamming attack • Environment • Infrastructure/Backbone WMNs • Role • Attacker • Defender
NTU OPLab Defender • Attributes • Nodes • Base Station • Mesh router(with 2 NICs) • Mesh client • Honeynode(with 3 NICs) • Guard Node
NTU OPLab Defender(cont’) • Attributes • Budget • Planning phase • Non-deception based • Deception based • Defending phase • Localization • Approximate • Precise
NTU OPLab Defender(cont’) • Strategies • Preventing the attacker from obtaining topology information. • Distracting the attacker • Real-time reaction
NTU OPLab Attacker • Attributes • Budget • Preparing phase • Mainly small-scale jammers • Mainly large-scale jammers • Attacking phase • Compromising mesh router
NTU OPLab Attacker(cont’) • Strategies • Preparing phase • Node compromising • Defense resources oriented • Easiest to find • Jamming • Range oriented • User number oriented • Traffic oriented
NTU OPLab Scenario Base Station Mesh router Compromised mesh router Jammed mesh router Honeynode Jammer Attacker
NTU OPLab Scenario – Defender Strategy 1(Preventing) Base Station Mesh router Which mesh router is important?
NTU OPLab Scenario – Defender Strategy 1(Preventing)(cont’) Base Station Mesh router Near Base Station?
NTU OPLab Scenario – Defender Strategy 1(Preventing)(cont’) Base Station Mesh router The one with the most users?
NTU OPLab Scenario – Defender Strategy 1(Preventing) Base Station Mesh router the one with the highest connectivity?
NTU OPLab Scenario – Defender Strategy 1(Preventing)(cont’) Base Station Mesh router Or the one with the most traffic?
NTU OPLab Scenario – Defender Strategy 2(Distracting) Base Station Mesh router Where to distract the jammer?
NTU OPLab Scenario – Defender Strategy 2(Distracting)(cont’) Base Station Mesh router Honeynode The region with the most users?
NTU OPLab Scenario – Defender Strategy 2(Distracting)(cont’) Base Station Mesh router Honeynode Or the region with the most traffic?
NTU OPLab Scenario – Defender Strategy 3(Real-time reaction) Base Station Mesh router Jammed mesh router Jammer How to localize a jammer?
NTU OPLab Scenario – Defender Strategy 3(Real-time reaction) (cont’) Base Station Mesh router Jammed mesh router Jammer Approximate the jammer’s location by the change of the range of boundary nodes.
NTU OPLab Scenario – Defender Strategy 3(Real-time reaction) (cont’) Base Station Mesh router Jammed mesh router Jammer Send out a guard node to discover the precise hearing range of boundary nodes Gotcha!