مقایسه عملکرد الگوریتم های زمان بندی در محیط تحرک شبکه

Network mobility (NEMO) supports a network moving as a whole, and this may cause the bandwidth on its wireless link varying with time and locations. The quick and frequent bandwidth fluctuation makes the resource reservation and admission control lack of scalability but with heavy overhead. A feasible solution for this problem is using scheduling algorithms to optimise the resource distribution based on the varying available bandwidth. In this paper, the performance comparison of several well-known priority queue (PQ) and fair queue (FQ) scheduling algorithms are given and their advantages and disadvantages in the NEMO environment are analysed. Moreover, a novel scheduling algorithm, named adaptive rotating priority queue (ARPQ), is proposed to avoid the problems of the existing algorithms. ARPQ operates with a “priority first, fairness second” policy and guarantees the delay bounds for the flows with higher priorities and maintain the reasonable throughput for the flows with lower priorities. The simulation results show that ARPQ outperforms all the existing scheduling algorithms in mobile networks, whose capacities are time-varying and location-dependent.