Towards the Benefit of Multi-hop Relaying in Opportunistic Networking

Hop count is an important parameter for routing strategies in wireless network. Particularly in the opportunistic networks, due to the intermittent connectivity between mobile nodes, it imposes great impact on the delivery performance in terms of delivery ratio and average latency. In the previous works, there are papers either claimed that two-hop is enough, or claimed that more hops increase the delivery delay, and also there is the attitude that more hops reduce more delivery delay. All of those conclusions are well justified under their specific assumptions and conditions, but the factors arousing such different attitudes towards multi-hop benefit have not be well investigated. In this paper, we establish a framework to analyze opportunistic multi-hop relaying benefit based the concept of Good Relay Ratio (GRR), and discuss the factors that impact max-benefit hop count in three typical multi-hop forms. Finally, we make a set of realistic trace-driven simulation to verify the analytical results. It is expected that the framework and result implications are meaningful to the routing strategy design in opportunistic networking.