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BLACK HOLE IN MANETSUBMITTED TO:--SUBMITTED BY:--Dr. SAPNA GAMBHIRINDRAJEET KUMARCSE DEPTT.MNW/887/2K11

ContentIntroduction to networkTypesWireless networkMobile ad-hoc network (MANET)Security issuesAttacks in MANETDetection & Resolving Query sessionReference

IntroductionNETWORKINGArea basedMedium based LAN WAN MANWIREDWIRELESS

Wireless NetworksNeed: Access computing and communication services, on the move

Infrastructure-based Networkstraditional cellular systems (base station infrastructure)

Wireless LANsInfrared (IrDA) or radio links (Wavelan)very flexible within the reception area; ad-hoc networks possiblelow bandwidth compared to wired networks (1-10 Mbit/s)

Ad hoc Networksuseful when infrastructure not available, impractical, or expensivemilitary applications, rescue, home networkingMany ApplicationsPersonal area networkingcell phone, laptop, ear phone, wrist watchMilitary environmentssoldiers, tanks, planesCivilian environmentstaxi cab networkmeeting roomssports stadiumsboats, small aircraftEmergency operationssearch-and-rescuepolicing and fire fightingChallenges in Mobile EnvironmentsLimitations of the Wireless Networkpacket loss due to transmission errorsvariable capacity linksfrequent disconnections/partitionslimited communication bandwidth

Limitations Imposed by Mobilitydynamically changing topologies/routeslack of mobility awareness by system/applications

Limitations of the Mobile Computershort battery lifetimelimited capacitiesMANET (Mobile ADHOC N/W)Introduction.Collection of mobile wireless nodesLinks are made & broken in arbitrarily way.No fixed infrastructureConstrained resourcesProblem Design a routing algorithm that are secure

Routing ProtocolsProactive protocolsTraditional distributed shortest-path protocolsMaintain routes between every host pair at all timesBased on periodic updates; High routing overheadExample: DSDV (destination sequenced distance vector)

Reactive protocolsDetermine route if and when neededSource initiates route discoveryExample: DSR (dynamic source routing),AODV.

Hybrid protocolsAdaptive; Combination of proactive and reactiveExample : ZRP (zone routing protocol)Security ISSUES INMANETSecurity Requirements in MANETAvailabilityData Confidentiality Data IntegrityNon-repudiation Attacks External attacksInternal attacksPassive attacksActive attacks

10 Threats10Attack in Manet Active attack & passive attack

Types of attack ( cont)Gray hole attack:-- As soon as it receive the packet from neighbor the attacker drop the packet.

Type of active attack.In some other gray hole attacks the attacker node behaves maliciously for the time until the packets are dropped and then switch to their normal behavior . Due this behavior its very difficult for the network to figure out such kind of attack. Gray hole attack is also termed as node misbehaving attack. Types of attack (cont)Warm hole attack:-- Wormhole attack is a severe attack in which two attackers placed themselves strategically in the network. The attackers then keep on hearing the network, record the wireless data.

BLACK HOLE ATTACK

A kind of denial of service where a malicious node can attract all packets by falsely claiming a fresh route to the destination and then absorb them without forwarding them to the destination. Co operative Black hole means the malicious nodes act in a groupRoute Requests in AODVBASEFHJDCGIKRepresents transmission of RREQZYBroadcast transmissionMNLRoute Request and Route ReplyRoute Request (RREQ) includes the last known sequence number for the destination

An intermediate node may also send a Route Reply (RREP) provided that it knows a more recent path than the one previously known to senderIntermediate nodes that forward the RREP, also record the next hop to destination

A routing table entry maintaining a reverse path is purged after a timeout intervalA routing table entry maintaining a forward path is purged if not used for a active_route_timeout intervalLink Failure A neighbor of node X is considered active for a routing table entry if the neighbor sent a packet within active_route_timeout interval which was forwarded using that entry

Neighboring nodes periodically exchange hello message

When the next hop link in a routing table entry breaks, all active neighbors are informed

Link failures are propagated by means of Route Error (RERR) messages, which also update destination sequence numbersThe black hole problem in current AODV protocolAODV is an important on-demand routing protocol that creates routes only when desired by the source node.When a node requires a route to a destination, it initiates a route discovery process within the network. It broadcasts a route request (RREQ) packet to its neighbors. (Figure 2)The black hole problem in current AODV protocol (cont.)

The black hole problem in current AODV protocol (cont.)Once the RREQ reaches the destination or an intermediate node with a fresh enough route, the destination or intermediate node responds by unicasting a route reply (RREP) packet (Figure 3) back to the neighbor from which it first received the RREQ.The black hole problem in current AODV protocol (cont.)

The black hole problem in current AODV protocol (cont.)Any intermediate node may respond to the RREQ message if it has a fresh enough route.The malicious node easily disrupts the correct functioning of the routing protocol and make at least part of the network crash.The black hole problem in current AODV protocol (cont.)

Cooperative black hole attack

SolutionSlightly modified AODV protocol by introducing Data Routing Information (DRI) Table (reliability table).

Another approachFidelity level:-----Collecting responses.

Choosing a response to forward data.Updating the fidelity level.Receiving acknowledgement and broadcasting fidelity packets

Conclusion and future work (cont.)In this seminar we have studied the routing security issues of MANETs, described the cooperative black hole attack that can be mounted against a MANET and proposed a feasible solution for it in the AODV protocol. ReferencesBo Sun,Yong Guan,Jian Chen,Udo , Detecting Black-hole Attack in Mobile Ad Hoc Network , The institute of Electrical Engineers, Printed and published by IEEE, 2003.Hongmei Deng, Wei Li, and Dharma P. Agrawal, Routing security in Wireless Ad-hoc Network,IEEE Communications Magazine, Issue 40, pp 7075,2002Latha Tamilselvan, Dr. V Sankaranarayanan Prevention of Co-operative Black Hole Attack in MANET JOURNAL OF NETWORKS, VOL. 3, NO. 5, MAY 2008