Performance analysis of the DQDB (Distributed Queue Dual Bus) protocol

In this paper, an analytical model of the message delay in the DQDB (Distributed Queue Dual Bus) network is investigated. The DQDB network has been adopted as a subnetwork for the IEEE 802.6 MAN (Metropolitan Area Network) standard. The DQDB network consists of two high speed unidirectional buses and a series of stations attached to both of the buses. Messages arriving at each station consist of several packets according to its size. This system is approximated into ‘B’[^X’]/G/1 with exceptional first service queueing model’ by defining the concept of service time on a packet. The service time for a packet is defined as the time from the instant the packet arrives at the transmission buffer until the time the packet is fully transmitted. By using the BASTA property and the average work in the system, the mean message delay time is obtained. [In Korean.]