DBS: a powerful tool for TCP performance evaluations

Network performance measurement tools, mainly used for TCP performance evaluations, have serious problems that their applications are limited to single point-to-point con guration and only the mean throughput for long term are measurable. Their major drawback is that they covers only a subset of the entire TCP functions and small variations of network systems. In this paper, we propose a TCP performance measurement tool called DBS (Distributed Benchmark System) which is aiming to give performance index with multi-point con guration and also in order to measure changes of throughput. It measure the performance of entire TCP functions in various operational environments. Experiments had been conducted using DBS to measure TCP end-to-end performance with various kinds of networks such as both LANs including FDDI, ATM, and HIPPI over ATM networks, and WANs including VSAT satellite channels. In short, DBS has the capability of both measuring and analyzing TCP performance more in details. Through these measurements, DBS unveiled details of TCP performance which cannot be realized by other existing tools.