Cache-and-forward Network Infrastructure In Urban Transport Systems

Today, efficient media content delivery in intermittent connected network has become a compulsory issue. In this thesis, we introduce a cache-and-forward network infrastructure which can reinforce the connectivity of intermittent connected mobile users in urban transport systems, so as to enable media content delivery among these users. The motivation of the study is inspired by the following two facts: one is the mobility pattern of commuters in urban transport systems, who tend to make regular journeys to the same place, and their trajectories show a high degree of temporal and spatial regularity. The other is the rapid development of high bandwidth wireless technologies, such as 802.11n, the transfer rate of which can achieve as much as 300Mbps~600Mbps. In this paper, delay tolerant network infrastructure is designed for intermittent commuters in urban transport systems.Our main contribution includes:(1) We propose network infrastructure which use store-and-forward routers to increase the contact opportunity of mobile commuters; our structure is mainly based on mobility pattern of vehicles and the high bandwidth of short range communication methods.(2) By analyzing the social pattern of mobile users, we also propose a router-centric prediction scheme that collects passenger historical trajectory information to determine the delivery scheme.(3) We test the feasibility of our infrastructure and delivery scheme based on real data set, which includes the real transport topology, the real timetable, and the real human flows. We analyze both the performance and the feasibility of our proposed network infrastructure and delivery scheme.In all, our proposed system is viable and can serve as a complement of the traditional wide area cellular data networks.