Connected Dominating Set Based Hybrid Routing Algorithm in Ad Hoc Networks with Obstacles

Routing based on a connected dominating set (CDS) is a promising approach in wireless ad hoc networks. Wu and Li proposed a distributed approximation algorithm for calculating CDS in a given connected graph. However, this algorithm is difficult when there are obstacles in the network topology. Obstacle hybrid routing algorithm (OHRA), presented here, addresses these issues. OHRA consists of mobility model, CDS election and hybrid routing. In obstacle mobility model, we introduce STANDBY nodes as relaying nodes between two nodes that are invisible. This paper then proposes a distributed CDS election algorithm in the presence of obstacles. This algorithm extends Wu and Li's algorithm and utilizes STANDBY nodes to connect the existing dominating-nodes belonging to dominating set. In addition, OHRA based on a CDS uses hybrid routing scheme (flooding-based approach and position-based approach) to forward around any obstacles. Eventually, an example is given to show that the proposed approach can form a CDS and successfully construct routes.