Abstract:Transmission Control Protocol(TCP) is tuned to perform well in wired networks or environment with low bit errors where packet losses occur mostly because of congestion.However,when TC Pis operated in high BER environment and suffers from significant losses due to bit errors,it does not make the best use of the available bandwidth of links because TC Phavles its current congestion window blindly.As a result,the performance of TC Pwould be deteriorated very much.Recently,the use of enhanced bandwidth estimation procedures within the congestion control scheme of TC Pwas proposed as a way of improving TC Pperformance over links affected by random loss.This paper first analyzes the problems faced by every bandwidth estimation algorithm implemented at the sender side of a TCP connection.Some proposed estimation algorithms,accuracy and performance are estimated.At the same time,the authors discuss the relationshi Pbetweent the bandwidth estimation accuracy and the fairness of protocol.Finally,this paper point out the further work should be done in future.