Demand and service matching at heavy loads: a dynamic bandwidth control mechanism for DQDB MANs

The alpha tuning mechanism for distributed queue dual bus (DQDB) networks is proposed. This mechanism achieves a match between the users´ demand and the resulting protocol´s service patterns. The use of a tunable α-parameter (representing some fictitious user population) and access protection lead to a dynamic bandwidth control capability. The inherently position dependent fairness problems of DQDB are overcome, especially at heavy loads. Fairly uniform delays and uniform success rates of transmission are seen for every user. Analysis and simulation studies for different load patterns, show that it outperforms the bandwidth balancing mechanism (BBM). This mechanism may be extended to any unidirectional channel, to achieve demand and service pattern match