Bus switched networks: An ad hoc mobile platform enabling urban-wide communications

In this paper we propose to leverage the public transportation system of any given city to obtain a scalable and efficient urban backbone by deploying an opportunistic network on buses. The paper proves that Bus Switched Networks (BSNs) are feasible for deployment in real cities and that they can meet the application level requirements for a large class of applications by ensuring high delivery ratio and acceptable delays under different conditions of packet load. We envision a multi-platform metropolitan network backhaul where BSNs play a relevant role and focus on a novel and lightweight probabilistic routing protocol. We prove that the protocol is highly effective in satisfying the loose QoS required by urban-wide delay-tolerant information services and perfectly scales to urban level. The protocol performance evaluation derives from an benchmark analysis of the protocol on three cities which have been selected to explore geo and structural diversity. Finally, the paper presents URBeS, an analysis platform that, given a specific city served by public transportation, produces bus mobility traces and traffic analysis for any given routing protocol.