A Load-Balancing QoS Routing Protocol for Wireless Mesh Networks

Abstract

由於在下一代的通訊系統中，無線網狀網路可作為連接使用者與網際網路的最後一哩之通道，無線網狀網路在近年來受到相當大的關注。傳統上，best effort traffic 在網際網路上扮演著重要的角色，是網際網路上主要的traffic組成。然而，隨著網路設備的capacity增加，需要服務品質保證的各種應用服務，像是VoIP或是video stream等等，也逐漸的出現在網際網路上。因此，無線網際網路作為連接網際網路與使用者端的骨幹網路，其繞徑協定必須要能同時處理best traffic與QoS traffic此二種異質性的traffic。在本篇論文中，我們提出LBQR來處理這樣的問題。此外，為了能夠在處理繞徑的問題時，兼顧網路資源的使用效率，我們還考慮了網路負載平衡的問題。LBQR在實作上係建立於DSDV上。我們並假設LBQR底層之MAC為802.11。從實驗的結果顯示，在throughput與admission ratio上，LBQR比其他的繞徑協定有著更好的效能。

Recently, wireless mesh networks (WMNs) have received much attention, because they can serve as the last-mile for broadband Internet access in the next-generation communication systems. Traditionally, best effort traffic plays an important role in the Internet. However, as the capacity of network device increases, there are more and more QoS-aware applications appearing in the Internet. Thus, to serve as the backbone for Internet access, the routing protocol for WMNs must be able to handle heterogeneous traffic (i.e., QoS traffic and best effort traffic) simultaneously. In this thesis, we propose a load-balancing QoS routing (LBQR) protocol that can handle the two kinds of traffic. In addition, for efficient use of resource, we take the network load-balancing into consideration. LBQR protocol is implemented in a distributed manner, which is based on the destination-sequenced distance-vector routing (DSDV) protocol. We have simulated the proposed protocol under the IEEE 802.11 medium access control. The simulation results show that the proposed LBQR protocol has better performance than other protocols in the aspect of throughput for best effort sessions, admission ratio and end-to-end delay for QoS sessions.