14-07-2012, 10:44 AM
Detection of Black Hole Nodes in Mobile ad-hoc network
Detection of Black Hole Nodes .ppt (Size: 2.09 MB / Downloads: 59)
Introduction
AODV routing protocol: Every node in ad-hoc network maintains routing table. It contains information about the route to the particular destination.
Black Hole Attack: A black hole attack is one kind of denial of service attack 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.
cooperative black hole attack: If these malicious nodes work together as a group then the damage will be very serious. This type of attack is called cooperative black hole attack.
Contribution of Latha tamilselvan Solution
This solution proposed a method for identifying multiple black hole nodes in group.
The methodology works with slightly modified AODV protocol by using Fidelity table contains fidelity level that acts as a measure of reliability of participating node.
If fidelity level of participating node drops to zero then it is considered to be a malicious node term as a Black Hole and it is eliminated.
Drawback of Latha Tamilselvan solution
Main drawback is time delay because source node waits for RREP packet, again waits to collect the acks and then decides only a safe route.
Another drawback is that finding route contains a node which has malicious tendencies but not a black hole node.
Choosing fresh route/suspected route
Choosing fresh route-
. If a node has already routed data packets from and through
some neighboring node, that node should be a normal one.
Suspected route-
If a node has not successfully routed any data packets from or through some neighboring node, that particular node may be a black hole node and needs to be inspected further
A node with high receiving/transmission ratio should be inspected with higher priority.