Minimizing the Average Waiting Time of Unequal-Size Data Items in a Mobile Computing Environment

Abstract

In a mobile computing environment, waiting time is an important indicator of customer satisfaction. In order to achieve better customer satisfaction and shorter waiting times, we need to overcome different constraints and make the best use of limited resources. In this study, we propose a minimization problem, allocating unequal-size data items to broadcast channels with various bandwidths. The main idea is to solve the problem in the continuous spaceRn. First, we map the discrete optimization problem fromZntoRn. Second, the mapped problem is solved inRnoptimally. Finally, we map the optimal solution fromRnback toZn. With the theoretical analyses, we can ensure the solution quality and execution speed. Computational experiments show that the proposed algorithm performs well. The worst mean relative error can be reduced to 0.353 for data items with a mean size of 100. Moreover, almost all the near-optimal solutions can be obtained within 1 millisecond, even forN=500, whereNis the number of data items, that is, the problem size.