Computing network coded data coverage in an opportunistic data dissemination network

Abstract

We consider an opportunistic wireless network where data repositories provide mobile users access to locally-cached data objects. In this setting using network/erasure coding to disseminate large data objects can greatly improve the performance and robustness of the network, but it becomes more difficult to plan, coordinate, and analyze the distribution of information. We introduce a simplicial data structure, the coverage complex, that captures enough of both the structure of the code and the geometry of the network that it can be used to draw conclusions about network coded data coverage. We give a distributed algorithm for computing the coverage complex based on local information, prove results on using it for coverage testing, and study more complicated cases where coverage testing can fail.