Efficient algorithms for the load-balanced demand point assignment problem in large-scale WLAN

One of the main issues to be addressed in the design of large-scale wireless LANs is that of assigning demand points to access points (APs) in such a way that each demand point is assigned to one of the available APs and the aggregate traffic demand (which is referred to as load in this paper) of all demand points assigned to any AP does not overload that AP. In this paper, we consider the problem of assigning demand points to APs with the objective of minimizing the maximum load among the set of APs, which qualitatively represents congestion at some hot spots in the network service area. We refer to this problem as the load-balanced demand points assignment problem. We formulated this problem as an integer linear program (ILP) and show that the problem is NP-hard. We propose two heuristic algorithms, namely MLPT and MAWDP, to obtain nearly optimal results in polynomial time. The effectiveness of these two algorithms are proven by the simulation results.

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