Analyzing Throughput of TCP in IEEE 802.11 Based Ad-hoc Networks

In order to allow programmers to follow conventional techniques while creating applications that uses an internet, software in the internet must provide the same semantics as a conventional computer system, it means it must guarantee reliable communication. Transport protocol provides reliability, which is fundamental for all the applications. The transmission Control protocol (TCP) is the transport level protocol that provides a completely reliable connection –oriented, full duplex stream transport service that allows two application programs to form a connection, send data in either direction, and then terminate the connection. Wireless multihop ad-hoc networks are network systems that can be deployed without relying on any infrastructure such as base stations hence are mobile networks such networks causes packet losses due to congestion and transmission errors . here a packet level model is proposed to investigate the impact of channel errors on the TCP performance over IEEE802.11 based multihop wireless networks A markov renewal approach is used to analyze the behaviour of TCP – Vegas . This paper motivates and describes the three key techniques employed by Vegas, and presents the results of a comprehensive experimental performance study—using both simulations and measurements the model takes into account the different proportions between the interference range and transmission range and adopting more accurate and realistic analysis to the fast recovery process. The results show that the impact of the channel error is reduced significantly due to the packet retransmissions on a per-hop basis and a small bandwidth delay product of ad hoc networks