Securing Wireless Sensor Networks From Sinkhole And Black Hole Routing Attacks

Wireless Sensor Network(WSN)technology is extensively incorporated in diverse application domains due to its dynamic self-organization capabilities,decentralized nature,data acquisition and processing expertise.A sensor network consists of large number of sensor nodes densely deployed to monitor the environment precisely and communicate data to sink node using the wireless medium.In sensor networks,it is very significant to provide secure communication with respect to different environments.One of the important security threats in WSN is routing attacks.These attacks are practiced to disconnect a sensor network from its central base station.Sensor network routing protocols are simple in terms of performance,route discovery etc.and for this reason they are more prone to routing attacks.There exist several routing attacks like Sinkhole,Black hole,Selective forwarding,Wormhole attacks etc.However Sinkhole attacks act as a platform for launching other attacks.Sinkhole attacks typically work by making a compromised node look especially attractive to surrounding nodes with respect to the routing algorithm.If a malicious node takes control of routing path then all the traffic flows through this compromised node.Hence,data transmission over the WSN becomes unsecure and results into loss or leakage of confidential information.Black hole is another routing attack where malicious node drops all the received packets instead of forwarding towards the right destination.Sinkhole and black hole are considered significant security threats for WSN because existing AODV routing protocol does not provide security.Generally,Sensor nodes are resource constrained in terms of radio range,processor speed,memory and power.Due to these constraints,existing encryption and hashing schemes in wired and wireless network are not deemed suitable for sensor networks and other non-cryptographic solutions proposed for handling routing attacks are not enough efficient and capable of detecting described routing attacks.Therefore,WSN requires effective and economical solution to circumvent these routing attacks.The main contributions of this dissertation are as follows.1)Developed a secure routing protocol AODV-SDR to detect and remove Sinkhole attack without using any type of encryption,keying mechanism and hashing function.AODV-SDR implements validation packets during route discovery in response of fake route reply generated by malicious node to identify the false destination.Destination sequence number is used for route freshness and higher sequence number shows more fresh route.Adversary pretends to have fresh route to destination by generating fake route reply having higher destination sequence number to attract network traffic.Source compares the destination sequence number of route replies and validation replies to identify fake destination.The numbers of transmissions are not increased significantly due to unicasting of validation packets on the forward path.AODV-SDR does not introduce any overhead on node‘s resources.2)Introduced AODV-BDR to detect and remove black hole attack by using neighbor-based authentication approach.Current approach detects malicious node during route discovery phase and does not introduce any specialized monitoring node.While discovering route,any intermediate node who claims to have a fresh route to destination sends its Next Hop Node(NHN)address to source in route reply packet.Source sends validation packet to NHN for authentication of route reply sent by Previous Hop Node(PHN).Validation packet checks either PHN is in the neighbor list of NHN and has fresh route to destination.If above conditions are satisfied then PHN is considered as a valid node otherwise malicious node.3)Proposed a secure routing protocol AODV-MDR to detect malicious node in wireless and adhoc networks.AODV-MDR described non-cryptographic approach because many cryptographic approaches are complex and power hungry therefore not suitable for resource constrained wireless sensor networks.Proposed secure routing protocol confirms the authenticity of claimed path and implements hop count verification by gratuitous RREP along with acknowledgement packets.Gratuitous RREP and acknowledgement packets are unicast on established routes so number of transmission does not increase significantly.4)Articulated another secure routing protocol AODV-BHDR to detect black hole attack in promiscuous mode.This mode allows node to overhear each network packet that reaches in its locality.Previous hope node(PHN)of route reply(RREP)generating node confirms the authenticity of claimed path by sending route confirmation packet to destination.Just neighbor node of route reply generating node confirms nodes trustworthiness and route confirmation.Although,this approach introduces little overhead on nodes resources but sustains routing security which was main objective of our research.