Design and Analysis of Secure and Efficient Relay based Cooperative Medium Access Control Protocol for Wireless Network

Abstract

Wireless networking changed the scenario from old style systems with low speed, large in size, low configuration output devices and low performance applications to higher speed and performance devices and application like laptops, mobile phones, gaming devices etc. A low cost and high data rate facility is provided by IEEE802.11 standard. There is 2 kind of scheme is available in IEEE802.11 MAC protocol. First one is distributed coordination function and second one is point coordinated function. DCF offer a facility to form ad hoc network spontaneously and PCF offer a facility to form network using infrastructure. So dcf helps to create infrastructure less ad hoc network and with the help of pcf infrastructure based network can be created. newlineWe can achieve better performance if we can maximize throughput, minimize delay and collision so these 3 factors play major role to improve network performance. Lots of research has been already done for enhancing network throughput. One approach is DMA (Different MAC Service Data Unit size (MSDU) Adaptation), where smaller MSDU size data packets are given to those stations whose transmission rates are lower. And higher transmission rate stations are given packets whose MSDU size is larger. Another approach is Different Initial Contention Window size Adaptation (DICWA). Here higher data rate stations have smaller initial contention window sizes, so their back off counter reduces to zero rapidly which implies better chance to access the channel rapidly in preference to those stations which have lower transmission rates. Another approach was to combine both the above mentioned techniques. newlineOur approach to increase the throughput is, through co-operation. In this type of communication, we take help to the nodes available near the source or destination nodes and have willingness to help others. Such nodes help to transmit data as volunteer. By this approach, the throughput can be increased and the delay can be reduced.