Mesh topology
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Mesh topology is a network layout in which devices connect to multiple other devices, creating many possible paths between any two points. Because there is more than one route, traffic can reroute around a failed or congested node, which makes the network self-healing. It contrasts with star, bus, and ring layouts, where a single hub or a single path is a point of failure.
How it works
Network topology describes how devices are interconnected. In a star topology, every device connects to one central hub, and if the hub fails, the network fails. In a mesh topology, devices connect to several neighbors, so the graph has redundant paths.
A full mesh connects every node to every other node, which is rarely practical wirelessly. Real wireless meshes are partial meshes: each device connects to the neighbors it can reach and relays for others, so multi-hop paths stitch the whole network together. When a node leaves or a link degrades, routing shifts to an alternate path automatically.
Devices manage how many peers they hold at once, since each connection costs energy and radio time. Well-designed meshes score candidate peers on quality, availability, and load, and bridge separate clusters of devices into one routable network.
Why it matters
Redundant paths are what make a mesh resilient. No single node is essential, so the network survives failures, movement, and interference that would take down a star or ring.
Mesh topology also scales coverage with participation: every device that joins can extend reach and add capacity, rather than adding load to a fixed hub.
How it relates to Offline Protocol
Offline Protocol forms a partial-mesh topology on ordinary phones. Its transport layer, DORS, has each device score and connect to a bounded set of peers over BLE and WiFi Direct, relay up to 8 hops, and reroute around nodes that leave. Devices in the same cluster connect as members, and devices that can see a second cluster connect as bridges, merging separate pockets of coverage into one network.
See peer-to-peer mesh networking for how clusters form and routes are chosen.
Frequently asked questions
What is the difference between mesh and star topology?
In a star, every device connects to one central hub, which is a single point of failure. In a mesh, devices connect to multiple neighbors, creating redundant paths so traffic can reroute around a failed node.
What is a partial mesh versus a full mesh?
A full mesh connects every node to every other node. A partial mesh connects each node only to the neighbors it can reach and relays traffic through intermediate hops, which is how wireless meshes work in practice.
Why is mesh topology called self-healing?
Because it has more than one path between points. When a node or link fails, routing automatically shifts to an alternate path with no manual reconfiguration.
