Broadcast repair for wireless distributed storage systems

In wireless distributed storage systems, storage nodes are connected by wireless channels, which are broadcast in nature. This paper exploits this unique feature to design an efficient repair mechanism, called broadcast repair, for wireless distributed storage systems with multiple-node failures. Since wireless channels are typically bandwidth limited, we advocate a new measure on repair performance called repair-transmission bandwidth, which measures the average number of packets transmitted by helper nodes per failed node. The fundamental tradeoff between storage amount and repair-transmission bandwidth is obtained. It is shown that broadcast repair outperforms cooperative repair, which is the basic repair method for wired distributed storage systems with multiple-node failures, in terms of storage efficiency and repair-transmission bandwidth, thus yielding a better tradeoff curve.