Mesh networking

A mesh network is a network topology in which each node relays data for the network. All mesh nodes cooperate in the distribution of data in the network.

Mesh networks can relay messages using either a flooding technique or a routing technique. With routing, the message is propagated along a path by hopping from node to node until it reaches its destination. To ensure all its paths' availability, the network must allow for continuous connections and must reconfigure itself around broken paths, using self-healing algorithms such as Shortest Path Bridging. Self-healing allows a routing-based network to operate when a node breaks down or when a connection becomes unreliable. As a result, the network is typically quite reliable, as there is often more than one path between a source and a destination in the network. Although mostly used in wireless situations, this concept can also apply to wired networks and to software interaction.

A mesh network whose nodes are all connected to each other is a fully connected network. Fully connected wired networks have the advantages of security and reliability: problems in a cable affect only the two nodes attached to it. However, in such networks, the number of cables, and therefore the cost, goes up rapidly as the number of nodes increases.

Mesh networks can be considered a type of an ad-hoc network. Thus, mesh networks are closely related to mobile ad hoc networks (MANETs), although MANETs also must deal with problems introduced by the mobility of the nodes.

Shortest path bridging allows Ethernet switches to be connected in a mesh topology and for all paths to be active.

Wireless mesh networks were originally developed for military applications. Mesh networks are typically wireless. Over the past decade, the size, cost, and power requirements of radios has declined, enabling multiple radios to be contained within a single mesh node, thus allowing for greater modularity; each can handle multiple frequency bands and support a variety of functions as needed—such as client access, backhaul service, and scanning (required for high-speed handoff in mobile applications)—even customized sets of them.

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