Evaluation of Flight Size Auto Tuning on 3.5G Commercial Wireless Packet Access Network

This paper evaluates a performance of Flight Size Auto Tuning (FS-AT), a TCP congestion control method for high speed wireless access networks, on the commercial network of 3G and 3.5G mobile communication systems. HSDPA expands a bandwidth of IMT-2000 to maximum at 14Mbps. The expanded bandwidth increases Bandwidth Delay Product (BDP) on an end-to-end channel. TCP is necessary to set congestion window (cwnd) larger than BDP to achieve maximum throughput of the channel capability. However, if cwnd becomes too large for BDP, TCP sender transmits packets excessively and packets are accumulated on a radio interworking node. To solve this problem, FS-AT is proposed as a congestion control method for high speed wireless access networks.