Performance Evaluation of CSMA (Carrier Sense Multiple Access) and MACA (Multiple Access with Collision Avoidance) over DSR

Abstract

Problem statement: Ad hoc wireless network (AWN) is a collection of mobile hosts forming a temporary network on the fly, without using any fixed infrastructure. QoS (Quality of Service) is the idea that transmission rates, error rates, and other characteristics can be measured, improved, and to some extent guaranteed in advance in ad hoc network however in particular concern for the continuous transmission of high bandwidth video and multimedia information this kind of content dependably transmitting is difficult in public networks using ordinary "best effort” protocols. Carrier Sense Multiple Access (CSMA) refers to a family of protocols used by stations contending for access to a shared medium like an Ethernet cable or a radio channel. MACA (Multiple Accesses with Collision Avoidance) Protocol is a Contention based Sender initiated Protocol which uses Three way handshaking means that RTS—CTS—Data packet exchange. It used in network congestion avoidance to help in determining the correct sending rate by binary exponential back off (BEB) Algorithm in which if any packet transmitted by a node is lost, the node uses the binary exponential back-off (BEB) algorithm to back off a random interval of time before retrying which is also inadequate trustworthy because of data sending acknowledgement is not received. Results: Packet delivery ratio (PDR) of the network decreases as the nodes are increases. CSMA gives constant PDR with different nodes while MACA gives higher PDR with minimum number of nodes and lower PDR as we increase the number of nodes. Average End-to-End delay increases as the number of nodes are increase but after certain number of nodes it’s again decreases as the nodes increases. CSMA gives better (lower) delay in comparison to MACA. Throughput are decreases as the nodes are increases in MACA, and in CSMA throughput are increases as the number of nodes are decreases. CSMA gives better throughput in comparison to MACA. Conclusion: The results obtained show that the analysis and performance evaluation of CSMA and MACA over DSR routing protocols. The performance has been measured with three parameters like packet delivery ratio, end-to-end delay and throughput.
Keywords: MANET; CSMA; MACA; DSR; PDR