Mesh topology

In short: In a mesh network devices are connected to each other over several paths. In a fully meshed network every device has a direct connection to every other one.

In more detail: If a line or node fails, routers use routing protocols to find another path. This makes the network very reliable.

In Depth

• Full mesh: n·(n−1)/2 connections, 15 for 6 devices. This gets expensive quickly, so it is used only for a few very important nodes.
• Partial mesh: only important nodes have several paths. That is the normal case, for example in the core of provider networks. The internet is partially meshed as well.
• Advantages: high reliability, several paths for load distribution.
• Disadvantages: high cost, complex planning and configuration.
• Wireless: the wireless variant is called mesh.

See also: network topologies, router