Towards a reliable memory repository built on an unreliable distributed sensor network

We propose a protocol for a distributed sensor network of unreliable components that causes the network to behave collectively as a memory device. The reliability of this memory device is greater than that of the individual components. Nodes with redundant data are not spatially collocated, so the system is robust to spatially localized damage. Address-datum pairs are submitted to the network at a designated interface point. The address in the pair determines the nodes that are used to store the pair. Messages are transformed on each hop, based on differences in addresses between the source and destination of the hop. The composition of these transformations produces a path dependent transformation on messages that provides reliable communication on the ensemble of unreliable parts. The reliability of the memory device is a tunable parameter that is achieved by adjusting the redundancy. We show how reliability improves with redundancy. We also show that optimum reliability is achieved with relatively modest redundancy.