Design and management of wireless mesh networks

无线网状网络(WMN)由通过无线链路互连的固定无线路由器组成，其中一小部分用作经由有线(例如，以太网)或无线(例如，WiMax)链路到互联网的网关。无线网状网面临的关键挑战之一是支持高吞吐量。最大可用带宽随着网状网中源和目的地之间的距离(即，移动设备和到互联网的网关之间穿越的无线路由器的数量)的增加而迅速下降；这种下降是由于来自相邻跳和路径的干扰造成的。例如，在具有相同和全向无线电范围的网络中，从单跳到两跳会使流的吞吐量减半。对于希望提供人们习惯的有线网络的延迟/吞吐量水平的网络提供商来说，这可能是灾难性的。WMN的容量可以使用具有多个(正交)信道的多无线电节点来增加；此外，通过仔细地调整无线路由器的发射功率，可以最小化干扰，从而增加容量。在这个项目中，我们打算：(A)为无线网状网的设计开发新的“统一”模型和工具，主要目标是增加无线网状网的容量；我们建议的独特之处在于，我们不是处理每个组件(例如，多通道、功率控制、成本等)。另外，正如迄今在文献中所做的那样，我们将使用统一的方法通过利用它们之间的密切关系来解决上述问题；以及(B)开发新的基于策略的自适应管理方案，为不同类别的用户提供服务质量支持和保证。这些方案背后的基本新颖思想是通过重新配置(例如，新的信道分配、新的拓扑)WMN来对异常(例如，故障和拥塞)作出反应，同时最小化(理想地避免)对正在进行的业务的影响。

Wireless mesh networks (WMNs) consist of stationary wireless routers interconnected by wireless links with a small fraction acting as gateways to the Internet via wired (e.g., Ethernet) or wireless (e.g., WIMAX) links. One of the key challenges facing WMNs is supporting high throughput. The maximum available bandwidth degrades rapidly with increasing distance between the source and destination in the mesh network (i.e., the number of wireless routers traversed between the mobile device and the gateway to the Internet); this degradation is caused due to interference from neighboring hops and paths. For example, in a network with identical and omnidirectional radio ranges, going from a single hop to two hops halves the throughput of a flow. This can be disastrous for network providers eying to provide the level of latency/throughput people are accustomed to with their wired networks.The capacity of WMNs can be increased using multi-radio nodes with multiple (orthogonal) channels; also, with careful adaptation of transmission power of wireless routers, one can minimize interferences and thus increase the capacity. In this project we intend to (a) develop new "unified" models and tools for the design of WMNs with the primary goal of increasing the capacity of WMNs; the uniqueness of our proposal lies in the fact that rather than treating each of the components (e.g., multi-channel, power control, cost, etc.) separately, as has been done so far in the literature, we will address the above issues using a unified approach by exploiting the intimate relationship among them; and (b) develop new policy-based adaptive management schemes to provide QoS support and assurance for different classes of users. The basic novel idea behind these schemes is to react to anomalies (e.g., failure and congestion) by reconfiguring (e.g., new channel assignment, new topology) the WMN while minimizing, ideally avoiding, the impact on the ongoing traffic.