A Tight Upper Bound on Online Buffer Management for Multi-Queue Switches with Bicodal Buffers
The online buffer management problem formulates the problem of queuing policies of network switches supporting QOS (Quality of Service) guarantee. In this paper. we consider one of the most standard models, called multi-queue switches model. In this model. Albers et al. gave a lower bound e/e-1, and Azar et al. gave an upper bound e/e-1 on the competitive ratio when in. the number of input ports, is, large, The), are tight. but there still remains it gap for small in. In this paper, we consider the case where m = 2. namely. a switch is equipped with two ports. which is called a bicordal buffer model. We propose an online algorithm called Segmental Greedy Algorithm (SG) and show that its competitive ratio is at most 16/13(similar or equal to 1.231), improving the previous upper bound by 9/7(similar or equal to 1.286). This matches the lower bound given by Schmidt.
buffer management multi-queue switches competitive analysis