Evaluation on parallel downloading method using HTTP over UDP

Abstract

(Parallel downloading) is one of the most effective technologies which speed up downloading large files on the Internet. As ubiquitous networks will be realized in the near future, downloading large files quickly is also very important on various types of networks. However, if we use the parallel downloading method on dynamic networks, such as ad hoc networks, it will not work well because of high loss rate and delay. To address this issue, we adopt UDP as a transport layer protocol instead of TCP which guarantees perfect in-order delivery unnecessary for file downloading. In our previous paper, a prototype of the parallel downloading method using HTTP over UDP is developed, and it is confirmed that our method outperforms the traditional method which adopts TCP, especially when loss rate is high and delay is large. In this paper, the key feature of the parallel downloading method using HTTP/UDP is evaluated through simple theoretical estimation and some simulation experiments. As a result, it is confirmed that the large division number tends to yield short download time. The proposed method can be an attractive protocol to distribute large files on dynamic networks composed of wireless links.