Directional Mac Protocol To Enhance Performance In Wlan.

Directional antenna systems not only enable users to have high quality links but also increase network throughput by allowing spatial reuse of wireless channels by the use of directional transmission. They come in different kinds varying from switched beam to adaptive beam forming antennas, single beam or multiple beam directional antennas. Traditional MAC protocols assume the use of omnidirectional antennas. Nodes with directional antennas are capable of transmitting in certain directions only and significantly reduce the chances of collision and increase the effective network performance. As part of my work a study of medium access control (MAC) scheme is studied for a WLAN wherein the nodes are equipped with smart antennas. This work clearly defines how spatial reuse can be achieved. Interference (radio noise) can decrease the signal-to-noise ratio (SNR) in a radio-based network. Directional antennas, can improve the SNR in a network. Simulation results performed In this research clearly indicates this by comparing nodes using omnidirectional antennas and the ones using directional antennas and then investigating the impact of these antennas on aggregate throughput and end-to-end delay of a WLAN.Security is another key issue to consider in wlans, in particular the wireless network is susceptible to attacks both on data content and user authentication such as denial of service, spoofing and eavesdropping. These attacks are due to the standards inherent flaws and space signal sharing caused by omnidirectional antennas it uses. In this work we will show the effectiveness of improving security in wlans using directional antennas by using a security definition software developed in Matlab.