The Telecommunications Advancement Organization of Japan (TAO) has put the concept of the Smart Gateway (SG) forward as a way of realizing safety and comfort for the drivers of Japan. The system will provide a variety of information, such as multimedia information that doesn't require a guarantee of transmission within a particular period, and cruising assistance information that does require a guarantee of transmission within a particular period, for driver's safety. The roadside system that is a component of the SG is discussed here. There are two requirements for this system: the first is step-by-step construction, because implementing it all at once would be both difficult and expensive. The second is an urgent-message guarantee that ensures the delivery of emergency information such as cruising-assistance information, etc., to drivers in real time. An autonomous decentralized system (ADS) will be used to meet the first requirement. A highly reliable Quality of Service (HQoS) control method that dynamically determines the priority level of data in response to drivers' needs and then supplies information, is proposed to meet the latter requirement. The architecture of this roadside system, and the HQoS control method based on ADS concepts, is discussed in this paper.
Abstract