Replication vs Erasure Coding in Data Centric Storage for Sensor Networks

In-network storage of data in wireless sensor networks (such as DCS-GHT, for instance) is considered a viable alternative to external storage since it contributes to reduce the communications inside the network and to favor data aggregation.

In current approaches it exploits pure data replication to assure data availability.
In this paper, we consider the use of n out of m codes and data dispersal in combination to in-network storage. In particular, given an abstract model of in-network storage we show how n out of m codes can be employed, and we discuss how this can be achieved in three cases of study. Since the configuration of the n out of m and of the network is particularly critical with respect to correct data encoding, we define framework aimed at evaluating the probability of correct data encoding and decoding. Then we exploit this result and simulations to show how, in the cases of study, the parameters of the n out of m codes and the network should be configured in order to achieve correct data coding and decoding with high probability.