Enhanced self-token protocol for high-speed multimedia communications

Local area networks (LAN) are considered an approach to supporting multimed ia services, such as voice, video, image, and data. To realize a multimedia LAN, the priority control function must be implemented for each traffic ch aracteristic. In this paper, we propose a multimedia protocol, called the E nhanced Self-Token Protocol, for transmitting multimedia services in a LAN environment. This method supports synchronous and asynchronous transmission by using two kinds of self-tokens, one for synchronous and the other for a synchronous transmission. Synchronous data have a higher priority than asyn chronous data. Therefore, the bandwidth and real-time transmission of synch ronous data are guaranteed. The remaining bandwidth is allocated to asynchr onous data. Performance evaluation via simulations shows that synchronous d ata can be transmitted within the predetermined interval. A comparison with FDDI shows that the proposed method has better throughput for asynchronous data. Furthermore, the proposed protocol can guarantee the upper limit of the Token Rotation Time (TRT) as in the Timed Token Protocol. (C) 1999 Scri pta Technica.