Mobile ad-hoc network is collection of temporary nodes that are capable of dynamic forming temporary network, self organize, and infrastructure less with nodes contains routing capability. That case we can't predict where the heavy traffic load comes and collision comes and drop actual data packet by the receiver's and intermediate nodes, because all nodes are self governing and self controllable. In this paper, we identify several network aspects, some of which are unique to mobile ad-hoc networks, that affect congestion, as for example: data rate; data drop causes (via bandwidth, collision) number of MAC retransmissions, Minimum Contention Window etc. before that we study and analyze the result in case of medium access control as ( 802. 11 and TDMA) and we found that 802. 11 case collision comes because that approach cannot use RTS/CTS method after that TDMA time we found time division multiple access but packet delivery ratio less as compare to 802. 11 after that we apply our CSMA/CA (carrier sense multiple access with collision avoidance mechanism) and we get collision free transmission and enhanced performance as compare to 802. 11 and TDMA. In our approach we use RTS/CTS method for collision avoidance and also apply and enhance CSMA/CA via congestion control through contention window overshooting scheme and jam control technique and analyze our result on the bases of throughput, end-to-end delay, routing overhead, packet delivery ratio etc. Here we use NS-2. 31 simulator for simulation of MANET and take comparative analysis between 802. 11, TDMA and CSMA/CA mechanism.

Tdma 802. 11 Manet Csma/ca