Due to their characteristics of dynamic topology, wireless
channels and limited resources, mobile ad hoc networks
are particularly vulnerable to a denial of service (DoS) attacks
launched by intruders. The effects of flooding attacks in network
simulation 2 (NS2) and measured performance parameters are
investigated, including packet loss ratio, average delay, throughput
and average number of hops under different numbers of attack
nodes, flooding frequency, network bandwidth and network size.
Simulation results show that with the increase of the flooding frequency
and the number of attack nodes, network performance
sharply drops. But when the frequency of flooding attacks or the
number of attack nodes is greater than a certain value, performance
degradation tends to a stable value.