  Adhoc wireless network with their changing topology and distributed nature
are more prone to intruders. The efficiency of an Intrusion detection system in
the case of an adhoc network is not only determined by its dynamicity in
monitoring but also in its flexibility in utilizing the available power in each
of its nodes. In this paper we propose a hybrid intrusion detection system,
based on a power level metric for potential adhoc hosts, which is used to
determine the duration for which a particular node can support a
network-monitoring node. The detection of intrusions in the network is done
with the help of Cellular Automata (CA). IDFADNWCA (Intrusion Detection for
Adhoc Networks with Cellular Automata) focuses on the available power level in
each of the nodes and determines the network monitors. Power Level Metric in
the network results in maintaining power for network monitoring, with monitors
changing often, since it is an iterative power optimal solution to identify
nodes for distributed agent based intrusion detection. The advantage of this
approach entails is the inherent flexibility it provides, by means of
considering only fewer nodes for reestablishing network monitors.
