An effective dynamic parallel downloading scheme with network coding in λ-grid networks

In lambda-grid networks, data files are stored on file servers as replicas, and those replicas are downloaded in parallel to reduce downloading time. However, parallel downloading raises the blocking probability of lightpath establishments because parallel downloading wastes many wavelength resources. To resolve this problem, we propose a parallel downloading scheme with network coding which encodes data at intermediate nodes. The proposed scheme enables file servers to store many replicas and thus replicas are easily downloaded with low wavelength resources. Through simulation experiments, we show that the proposed scheme improves the blocking probability and the downloading time efficiently.