Two things called “mesh”
“Mesh” is used for two quite different setups, and the difference matters when you are deciding what will work without infrastructure.
- Home mesh Wi-Fi is a product category: several access points placed around a house or office that work together as one Wi-Fi network. Your phone, laptop and television connect to them the way they would connect to any router.
- A wireless mesh network in the general sense is one in which the devices themselves pass traffic along for each other. There may be no access point at all. A mesh network of phones, sensors or radios is this second kind.
Both use the mesh idea of many links instead of one centre. They differ in which devices relay.
How home mesh Wi-Fi works
A single router may not cover a whole home. The Wi-Fi Alliance’s technology overview of EasyMesh notes that walls, floors and wiring affect coverage, and that the number of connected devices adds traffic. Mesh systems answer this with more access points.
Wi-Fi EasyMesh is the Wi-Fi Alliance’s standards-based approach to networks with multiple access points. In its description, EasyMesh access points work together to form a unified network, guide devices to the best access point, and change the network’s structure as conditions change. It is also meant to let access points from more than one vendor join the same network.
The links between the access points are often called the backhaul. prplMesh, an open-source EasyMesh implementation from the prpl Foundation, describes its backhaul handling as preferring wired connections for reliability and falling back to wireless when needed. The same project lists settings such as network names and passphrases syncing across all the nodes, and steering devices to the best access point.
IEEE 802.11s is a separate standard. It is the IEEE amendment that describes how 802.11 stations form self-configuring multi-hop networks, and router software such as OpenWrt supports it, so it is one way to build the wireless links between access points.
The phone is a client, not a relay
In a home mesh, your phone is an ordinary Wi-Fi client. It joins one access point at a time, and the access points decide how its traffic crosses the backhaul. The phone never forwards traffic for the laptop in the next room.
That has two consequences. Coverage ends where the access points end; step outside their range and your devices lose the network, even if another phone is a few metres away. And if the access points lose power, the network is gone for every device at once.
How a device-to-device mesh works
In a device mesh, every participant can relay. The Bluetooth SIG’s mesh FAQ describes a network with no central hub or routing nodes in which messages travel over multiple paths, with mains-powered nodes relaying for others. RFC 2501 describes mobile ad hoc networks as mobile nodes that route for each other with no fixed infrastructure, a model covered in what is a mobile ad hoc network.
Phones can join this kind of mesh too, using software that runs on each device. Wi-Fi itself also has device-to-device modes: the Wi-Fi Alliance describes Wi-Fi Direct as letting devices create their own networks with no access point, and Wi-Fi Aware as direct device-to-device connections without traditional network infrastructure. Those give devices direct links; relaying a message across several devices is left to the software above them. Can phones form a mesh network without internet? covers what that software has to do.
Side by side
| Home mesh Wi-Fi | Device-to-device mesh | |
|---|---|---|
| Who relays | Access points only | The devices themselves |
| Your phone’s role | Client of one access point | A node that can forward for others |
| Needs installed hardware | Yes, the access points | No |
| Main purpose | Coverage for one network and internet line in a building | Communication where infrastructure is missing or down |
| Example standards | Wi-Fi EasyMesh | Bluetooth Mesh, IETF MANET protocols |
Which one you need
If the goal is good Wi-Fi and internet in every room, a home mesh is the right tool, and EasyMesh is the standard to look for if you want to mix vendors.
If the goal is for devices to reach each other when there is no access point, no power, or no internet, a home mesh does not help, because every device still depends on the access points. That needs a device-to-device mesh, where the phones or sensors carry each other’s messages.