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Most-urgent-first protocol for real-time wireless channels in a digital cellular/PCN environment
Published March 15, 1995 by Intelligent Transportation Systems in United States
Event: Intelligent Transportation: Serving the User Through Deployment~Proceedings of the 1995 Annual Meeting of ITS America
Providing mobile clients with real-time access to a shared information base in a digital cellular or personal communication network (PCN) environment is vital to the success of many future intelligent transportation systems (ITS) applications. The well-known limiting factors of such an environment are the relatively low channel bandwidth, a small number of available channels, and a potentially large number of users/clients to serve.
A most-urgent-first (MUF) protocol is proposed to solve the problem of accessing reverse (client-to-server) traffic channels, where mobile clients compete to convey their requests to the server. A method is also presented for evaluating the urgency of each client's request for traffic information. The MUF protocol gives more urgent requests higher priority, responds faster to more important inquirers, accommodates more clients in each channel, and allows information sharing among a potentially large number of clients. Moreover, all services can be provided in real-time. Finally, an UltraSAN model has been developed to evaluate the performance of the MUF protocol. Some of the issues related to operation of the MUF protocol are also discussed