Mobile Intelligence

18.5 SIMULATION RESULTS

NS-2 simulator has been widely used for evaluating ad hoc routing protocols. It uses two-ray ground reflection model [23] for radio propagation, which accounts for physical phenomena such as signal strength, propagation delay, capture effect, and interference. The transmission range for a node is set to 250 m. NS-2 deploys random waypoint model for mobility, in which a node starts from a random point, waits for a duration determined by pause time, then chooses another random point, and moves to the new point with a velocity uniformly chosen between 0 and maximum velocity “V_max.” The medium access control (MAC) protocol is set to IEEE 802.11 distributed coordination function (DCF) and the routing protocol to DSR. In our simulations, the traffic from sender to receiver is a constant bit rate (CBR) flow with data rate of 2 Mbps and packet size of 512 bytes. Instead of maintaining CBR flows between fixed set of senders and receivers for the entire simulation run, CBR flows are dynamically varied between randomly chosen set of senders and receivers. Such a setup increases the total count of discovered routes and in turn exposes benign nodes to more malicious nodes. The simulation run for each run is 300 s, and the maximum and minimum duration for CBR flows are 20 and 40 s, respectively.

18.5.1 SMRTI and Malicious Nodes

SMRTI is implemented as a wrapper to DSR protocol in NS2 and a mobile node with SMRTI enabled is known as SMRTI node. During route discovery stage, ...