Geographical cluster-based routing in sensing-covered networks

The relationship between coverage and connectivity in sensor networks has been investigated in recent research treating both network parameters in a unified framework. It is known that networks covering a convex area are connected if the communication range of each node is at least twice a unique sensing range used by each node. Furthermore, geographic greedy routing is a viable and effective approach providing guaranteed delivery for this special network class. In this work, we will show that the result about network connectivity does not suffer from generalizing the concept of sensing coverage to arbitrary network deployment regions. However, dropping the assumption that the monitored area is convex requires the application of greedy recovery strategies like traversing a locally extracted planar subgraph. This work investigates a recently proposed planar graph routing variant and introduces a slight but effective simplification. Both methods perform message forwarding along the edges of a virtual overlay graph instead of using wireless links for planar graph construction directly. In general, there exist connected network configurations where both routing variants may fail. However, we will prove three theoretical bounds which are a sufficient condition for guaranteed delivery of these routing strategies applied in specific classes of sensing covered networks. By simulation results, we show that geographical cluster-based routing outperforms existing related geographical routing variants based on one-hop neighbor information. Furthermore, simulations performed show that geographical cluster-based routing achieves a comparable performance compared to variants based on two-hop neighbor information, while maintaining the routing topology consumes a significantly reduced amount of communication resources.