A Mobile Ad Hoc Network (MANET) is more prone to security threats than other
wired and wireless networks because of the distributed nature of the network.
Conventional MANET routing protocols assume that all nodes cooperate without
maliciously disrupting the operation of the protocol and do not provide defence
against attackers. Blackhole and flooding attacks have a dramatic negative impact
while grayhole and selfish attacks have a little negative impact on the performance
of MANET routing protocols.
Malicious nodes or misbehaviour actions detection in the network is an important
task to maintain the proper routing protocol operation. Current solutions
cannot guarantee the true classification of nodes because the cooperative nature
of the MANETs which leads to false exclusions of innocent nodes and/or good
classification of malicious nodes. The thesis introduces a new concept of Self-
Protocol Trustiness (SPT) to discover malicious nodes with a very high trustiness
ratio of a node classification. Designing and implementing new mechanisms that
can resist flooding and blackhole attacks which have high negative impacts on
the performance of these reactive protocols is the main objective of the thesis.
The design of these mechanisms is based on SPT concept to ensure the high
trustiness ratio of node classification. In addition, they neither incorporate the
use of cryptographic algorithms nor depend on routing packet formats which make
these solutions robust and reliable, and simplify their implementations in different
MANET reactive protocols.
Anti-Flooding (AF) mechanism is designed to resist flooding attacks which relies
on locally applied timers and thresholds to classify nodes as malicious. Although
AF mechanism succeeded in discovering malicious nodes within a small time, it
has a number of thresholds that enable attacker to subvert the algorithm and
cannot guarantee that the excluded nodes are genuine malicious nodes which was
the motivation to develop this algorithm. On the other hand, Flooding Attack
Resisting Mechanism (FARM) is designed to close the security gaps and overcome
the drawbacks of AF mechanism. It succeeded in detecting and excluding more
than 80% of flooding nodes within the simulation time with a very high trustiness
ratio.
Anti-Blackhole (AB) mechanism is designed to resist blackhole attacks and relies
on a single threshold. The algorithm guarantees 100% exclusion of blackhole nodes
and does not exclude any innocent node that may forward a reply packet. Although
AB mechanism succeeded in discovering malicious nodes within a small time, the
only suggested threshold enables an attacker to subvert the algorithm which was
the motivation to develop it. On the other hand, Blackhole Resisting Mechanism
(BRM) has the main advantages of AB mechanism while it is designed to close
the security gaps and overcome the drawbacks of AB mechanism. It succeeded in
detecting and excluding the vast majority of blackhole nodes within the simulation
time
