• SABBAR INSAIF JASIM Lecturer in Al-Dour Institute,Salah-Adden, Dour.
Keywords: transmission control protocol, protocol data unit, user datagram protocol, customer-provided equipment, ACK


One of the imperative elements of TCP is the congestion control of the system which happen when numerous info streams touch base at a router whose yield limit is not as much as the whole of the data sources. This paper introduced how Old Tahoe (Congestion Avoidance) could and Tahoe (Fast Retransmit) affect the congestion control. The system was simulated using Network Simulation Program (NetSim) to study the performance of system in terms of delay and utilization for Old Tahoe (Congestion Avoidance) and Tahoe when the congestion occurred and when there is no congestion and no error  and the results showed that fast retransmit was better utilization and low delay than congestion avoidance


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