Experiment results and analysis of FTP and HTTP transmission over satellite network

摘要

In this paper, we present and analyze the results of two typical TCP applications - FTP and HTTP - over ATM based satellite network. The transmission of FTP and HTTP was done via Ka band KOREASAT-3. In FTP experiment, we measured the throughput varying TCP window size. The maximum throughput of file transfer was about 3 Mbps when the TCP socket size was 1Mbytes. When the TCP socket size is more than l Mbytes, the throughput was degraded. In the case of memory-to-memory transfer over satellite channel, the throughput mainly depends on the TCP window. But when TCP buffer size was increased to improve TCP throughput in satellite network, the TCP application that needs access to other media such as FTP was affected by other various factors. In RTTP experiment, we measure the throughput of HTTP version 1.0 and 1.1 under satellite network condition. In HTTP 1.0, the web browser can open several TCP connections simultaneously to access the objects linked in web pages. But HTTP 1.1 does not permit the multiple TCP connection in a time. HTTP version 1.1 supports the pipeline option. In the experiment, we measure the throughput of HTTP with various options in satellite network condition and analyzed the internal behaviors. HTTP 1.1 with pipelining option provided the best performance of all HTTP version and options.