為了滿足人們對於行車便利性的需求，應用於車輛的導航系統產品日益更新。它不但提供駕駛者路線導引的功能，並包含其他行車所需的相關資訊，因此漸漸地變得越來越普及。另外在車輛隨意網路(VANET)上實現網路漫遊的想法，其相關議題受到人們廣為注意及討論。經由散佈在路邊的存取點(APs)，在車上的人們即可透過這些基礎建設來存取無線網路。然而無線網路的交通負載，往往是不均勻的散佈在各個存取點上，這會進而影響到各個使用者的頻寬分配公平性，尤其是在由好幾百輛具有高移動性的汽車所組成的車輛隨意網路中，情況會更為嚴重。因此我們研究連結控制來達到存取點之間的負載平衡，進而提升整體的系統的效能和公平性。
本篇論文提出一個根據導航路線，在路線上未來可能發生換手的地點，預先做選擇存取點的動作，進而替每輛汽車規劃出一個連結存取點的順序排程(RSU-association-schedule)的演算法，以達到在各個存取點之間的負載平衡。實驗結果顯示我們的方法確實能夠改善整體的公平性。

In-vehicle navigation products have been thriven constantly for fulfilling people’s need in convenience. It does not only provide traveling route but also related information required by drivers. Therefore, vehicle navigation systems have been widely used by lots of drivers. Internetworking over Wireless Vehicular Ad Hoc Networks (VANET) is getting more attention and discussion. People can use mobile devices, including smart phones, laptops and PDAs, to associate with nearby access points which are installed on the roadside for roaming in a wireless network. However, the traffic load often displays unbalanced distribution among the APs in the WLANs, which leads to unfair bandwidth share of each user. This situation may be critical in VANET composed of thousands of vehicles which have high mobility. Hence, we study association control to achieve load balancing among APs, and improve the fairness and overall performance further.
In this thesis, we propose a novel algorithm of association control for planning an RSU-association-schedule by selecting an appropriate RSU in advance to achieve load balancing among RSUs. The simulation results show our scheme possesses the improvement of the fairness.

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