Abstract
This paper presents a novel architectural solution to address the problem of scalable routing in very large sensor networks. We develop a routing solution off-network control processing (ONCP) that achieves control scalability in large sensor networks by shifting certain amount of routing functions to an ldquooff-networkrdquo server. A tiered and hybrid routing approach, consisting of ldquocoarse grainrdquo global routing, and distributed ldquofine grainrdquo local routing is proposed for achieving scalability by avoiding network wide control message dissemination. We present the ONCP architectural concepts and analytically characterize its performance in relations to both flat and hierarchical sensor routing architectures. We also show ns2 based experimental results indicating that for large sensor networks with realistic data models, the packet drop, latency and energy performance of ONCP can be significantly better than those for flat and cluster-based protocols.