A speed-based adaptive dynamic parallel downloading technique

In this paper, we describe adPD, an improved parallel downloading approach for Peer-to-Peer environment. adPD assigns each server equal portion of file as large as possible, and ensures client downloading from each server without interrupt. And after faster servers finish their own work, adPD reallocates part of unfinished work of some slower servers to them. This reallocation is proportional to the ratio of server speed. By this means, adPD dynamically adjusts the proportion of a file retrieved from each server during the downloading process to match the bandwidth of each connection, and also reduces the number of block requests as many as possible. Our experiment results show that adPD is an effective parallel download scheme in Peer-to-Peer environment.