Energy Efficient Distributed Storage Systems with LT-Codes in Resource-Limited Wireless Systems

In this paper we study the problem of designing a distributed data storage system using rateless codes for resource constrained systems such as Wireless Sensor Networks (WSNs). Rateless codes, e.g. LT-codes, can achieve reduced complexity of both encoding and decoding, which caters well to the nature of limited resources in such systems. However, data in WSNs is inherently decentralized and that poses an additional challenge when attempting to build codes with unconventional degree distributions. We propose an energy efficient distributed dissemination and coding scheme to build a decentralized LTcodes based storage over a network of resource-limited nodes to provide data survivability against possible failures. In the proposed scheme, each sensor node assigns selection probabilities to storage nodes using Robust Soliton Distribution (RSD) in a distributed fashion, and disseminates its data over the storage network randomly. The proposed scheme is compared to similar schemes in the literature by means of simulations. The results show that energy consumption can be substantially reduced while achieving the required storage requirements.