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Various recent intelligent transport system projects are promoting vehicle safety and efficient vehicular traffic control all over the world. One of ITS applications is a system that solves road traffic problems by using vehicular communications technology. Inter-vehicle communication (IVC) is the communications technology for vehicles to exchange moving vehicle information by wireless networks without any base stations. The Vehicular Ad-hoc Network (VANET) is expected to provide new applications for passengers of vehicles by enabling vehicles to communicate with each other via IVC as well as with roadside base stations via roadside-to-vehicle communications. However, when each vehicle transmits its own information to neighboring vehicles, the amount of information being transmitted increases significantly. To solve this problem, we present a novel real-time recognition method for vehicular traffic congestion via VANET with IVC. Vehicles collect the original GPS information of other vehicles by communicating with each other, and they create content that may be useful for drivers by analyzing that original information. The proposed method can reduce the information amount and deliver the analyzed contents to other vehicles efficiently. Computer simulation results show that the proposed method provides real-time information of vehicular accidents and traffic congestion to distant vehicles accurately.

Many people have suffered and died due to a lot of large-scale disasters such as earthquake, fire, and terrorism, etc. In disasters where most evacuators become panic, two things are necessary for their immediate evacuation. The first is to estimate the location of the disaster occurrence. The second is to construct an evacuation support system that searches for safe and efficient evacuation routes. In this paper, we propose Emergency Rescue Urgent Communication — Evacuation Support System (EUC-ESS) based on Mobile Ad-hoc networks (MANET) composed of many mobile terminals. Using experiments and computer simulations, we show that this system would support evacuators in determining appropriate routes for survivors.

Inter-Vehicle Communication (IVC) is one of the most important technologies to realize advanced Intelligent Transport Systems (ITS). We extensively apply the IVC technology to the communications between pedestrians and vehicles. We call this kind of communications VPEC (Vehicle-PEdestrian Communications). The objective of this paper is to present an effective control scheme for VPEC and to evaluate the performance of proposed scheme by experiments. We deal with direct communications between pedestrians and vehicles. Due to the battery shortage of pedestrians' terminals (p-node), we have presented a reflect-transmission scheme. In this paper, we propose a new access protocol for reflect-transmission scheme, and show its validity by various experiments with several vehicles.

Content Distribution Networks (CDNs) are highly advanced architectures for networks on the Internet, providing low latency, scalability, fault tolerance, and load balancing. One of the most important issues to realize these advantages of CDNs is dynamic content allocation to deal with temporal load fluctuation, which provides mirroring of content files in order to distribute user accesses. Since user accesses for content files change over time, the content files need to be reallocated appropriately. In this paper, we propose a cost-effective content migration method called the Step-by-Step (SxS) Migration Algorithm for CDNs, which can dynamically relocate content files while reducing transmission cost. We show that our method maintains sufficient performance while reducing cost in comparison to the conventional shortest-path migration method. Furthermore, we present six life cycle models of content to consider realistic traffic patterns in our simulation experiments. Finally, we evaluate the effectiveness of our SxS Migration Algorithm for dynamic content reconfiguration across time.