Wireless mesh networks have been receiving a great deal of attention as a broadband access alternative for a wide range of markets, including those in the metro, public-safety, government, energy, transportation, hospitality, education, enterprise, carrier-access and residential sectors. An increasing number of deployments today are composed of larger clusters of nodes; previously, there were more point-to-point and point-to-point-to-multipoint deployments. Mesh networks with nodes that have two or more active associations with surrounding nodes can support ranges exceeding one or two hops as they relay traffic to and from the wired broadband connection.
In this environment, hybrid technologies or hierarchical network organization are used to build and optimize the network through effective distribution of client (wireless user) access and backhaul connectivity. A cluster may have multiple wireless or even solar-powered nodes and one wired backhaul node acting as the gateway to the Internet or other fixed-network resources. Clients can theoretically connect from anywhere in or around the wireless network to that resource.
Critical topics for wireless access networks include provisioning of high network capacity, service differentiation, node-to-node encryption, client security and fast mobile roaming. Throughput and latency are also key factors for the viability of such networks.
In this context, the hardware design of the nodes (single-radio vs. multiradio), the mesh algorithms and protocols that run the system, and configuration flexibility are all crucial considerations that affect the performance of the scalable mesh fast-reroute function.
To ensure a scalable mesh network, wireless nodes should be self-configuring, self-tuning and self-healing. This makes it possible to deploy extremely large-scale, intelligent, high-speed networks with predictable performance and resiliency.
Such nodes also make a scalable mesh network easier to deploy than a wired network. The nodes--and the resulting network--can be turned up quickly, enabling high user densities and providing a stable carrier-grade infrastructure for residential and corporate applications.
While customers expect to receive voice, video and data services, many existing wireless mesh networks cannot adequately support all of those applications simultaneously. As these networks are implemented, problems commonly are not detected until the network exceeds two or three hops; only then are high latency and low throughput recognized, and the limited reach of the network fully realized.
In these networks, data applications such as Internet access can achieve acceptable performance; however, latencies are too high for voice and video streaming, which, if implemented, could take the network down.
On the other hand, some of the largest wireless mesh networks today provide extremely high throughput and can maintain it, with minimal latency, across a dozen or more wireless hops. These large networks are capable of supporting such bandwidth-intensive and timing-sensitive applications as real-time streaming video, data acquisition, automated alarm triggering and control systems.
It is also important for wireless mesh networks to support mobile roaming. Some can support mobile roaming handoff at speeds of 60 miles per hour; even better, some wireless mesh nodes employing optimal fast-roaming algorithms can support handoff of mobile calls at speeds of more than 200 mph--the speeds of international railway systems--and provide real-time Internet access, Wi-Fi voice and streaming video surveillance.
