Mesh node

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. It can be applied to both wired and wireless networks.

Wireless mesh networks can be considered a type of Wireless ad hoc network. Thus, wireless mesh networks are closely related to mobile ad hoc networks (MANETs). Although MANETs are not restricted to a specific mesh network topology, Wireless ad hoc networks or MANETs can take any form of network topology.

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 that all its paths are available, 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.

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

Wireless mesh radios are different from Wi-Fi ad hoc, which are commonly found in smart phone ad hoc networks, laptop computers, and wireless LANs. Wireless mesh radios primarily support voice rather than desktop or software computing. A radio device is different from a computer or smart phone, since the latter is programmable and has multi-function compute capability.

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