Interest in smart cities is rapidly rising due to the global rise in urbanization and the wide-scale instrumentation of modern cities. Due to the considerable infrastructural cost of setting up smart cities and smart communities, researchers are exploring the use of existing vehicles on the roads as "message ferries" for the transport data for smart community applications to avoid the cost of installing new communication infrastructure. In this paper, we propose an opportunistic data ferry selection algorithm that strives to select vehicles that can minimize the overall delay for data delivery from a source to a given destination. Our proposed opportunistic algorithm utilizes an ensemble of online hiring algorithms, which are run together in passive mode, to select the online hiring algorithm that has performed the best in recent history. The proposed ensemble based algorithm is evaluated empirically using real-world traces from taxies plying routes in Shanghai, China, and its performance is compared against a baseline of four state-of-the-art online hiring algorithms. A number of experiments are conducted and our results indicate that the proposed algorithm can reduce the overall delay compared to the baseline by an impressive 13 to 258 .
During large-scale disasters, such as the Great East Japan Earthquake in 2011 or Kumamoto huge Earthquake in 2016, many regions were isolated from critical information exchanges due to problems with communication infrastructures. In those serious disasters, quick and flexible disaster recovery network is required to deliver the disaster related information after disaster. In this paper, mobile cloud computing for vehicle server for information exchange among isolated shelters in such cases is introduced. The vehicle with mobile cloud server traverses the isolated shelters and exchanges information and returns to the disaster headquarter which is connected to Internet. DTN function is introduced to store, carry and exchange message as a message ferry among the shelters even in the challenged network environment where wired and wireless communication means are completely damaged. The prototype system is constructed using Wi-Fi network as mobility network and a note PC mobile cloud server and IBR-DTN and DTN2 software as the DTN function. Sensors in future smart cities will continuously monitor the environment in order to prevent critical situations and waste of resources or to offer new services to end users. Likely, the existing networks will not be able to sustain such a traffic without huge investments in the telecommunication infrastructure. One possible solution to overcome these problems is to apply the Delay Tolerant Network (DTN) paradigm. This paper presents the Sink and Delay Aware Bus (S&DA-Bus) routing protocol, a DTN routing protocol designed for smart cities able to exploit mobility of people, vehicles and buses roaming around the city. Particular attention is put on the public transportation system: S&DA-Bus takes advantage of the predictable and quasi-periodic mobility that characterizes it.