Abstract:

High-bandwidth delay product （HBDP） networks often have a very big slow-start threshold. In the slow start phase, the current TCP＇ s exponential increase strategy often increases the congestion window immensely after one round trip time. This easily results in network congestion and especially harmGSS （Gentle Slow Start）. When t   the congestion window size is small, the increase policy of GSS isnear the original exponential method; while the window size becomes bigger, the increa  se slows down and finally smoothly switches to the congestion avoidance phase. The NS2 simulation results show that GSS has higher bottleneck utilizatio  n, a smaller queue size and lower drop rates than slow start.

Key words: high-bandwidth delay product, TCP, congestion control, slow start