A Study of Capacity-aware Traffic Control and Anycast Framework in Hierarchical Wireless Mesh Networks

• Main Authors: Pa Hsuan, 宣拔
• Other Authors: Chyi-Ren Dow
• Format: Others
• Language: en_US
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/48880936780876048384

博士 === 逢甲大學 === 資訊工程所 === 99 === Wireless techniques are convenient for network topology construction, such as wireless mesh networks (WMNs), mobile ah-hoc networks (MANets), and vehicular ad-hoc networks (VANets) to provide Internet and peer-to-peer data access services. Although route redirection traffic control schemes and dynamic routing metrics can be used to improve the performance of WMNs, available network bandwidth will be consumed for control message exchange. Anycast techniques for MANets and VANets can be used to find the nearest services through anycast addresses. However, searching for resources on networks often depends on the broadcast mechanism, which usually results in large overhead and consumes network resources. In this dissertation, we study the capacity-aware traffic control framework and anycast-based service discovery schemes in hierarchical wireless networks to improve the network performance. The traffic control framework can be used to dispatch data traffic in a multipath manner and improve utilization of wireless links and forwarding latency. A hierarchical queue framework is proposed to monitor and manage network traffic without the effort of message exchange. Through the monitored capacity information, the proposed traffic control system can automatically adjust the utilization of each path and Internet gateway. At the service discovery scheme aspect, anycast schemes can be used to reduce the request messages and decrease the response overhead received from duplicated packets. Furthermore, our scheme can support the discovery of K services. Three service discovery strategies are proposed to provide different reliability and network overhead requirements. This work implements the proposed traffic control system on NS2 and the IPv6 enabled Linux 2.6 platforms to evaluate the feasibility and system performance. The experimental results show that the behavior of the long-term delay model can be applied to short-term traffic control methods in WMNs since a large amount of data traffic allows the monitored system performance to rapidly converge to a stable state. Also, the anycast-based service discovery schemes are implemented on GloMoSim and IPv6 enabled Linux 2.6 platforms. The results demonstrate the efficiency of the anycast-based service discovery schemes and the feasibility of our IPv6-based anycast system.