In a home with several access points or a mesh system, the expectation is simple: I walk from the living room to the bedroom and the phone switches on its own to the nearest device. In practice the opposite often happens. The phone stays attached to the downstairs access point, with a very weak signal, while the one in the next room is idle. Understanding why this happens helps you fix it.
Who decides when to roam
The key point is that in Wi-Fi the decision to change access point belongs to the device, not the network. The phone or laptop evaluates the signal it receives and, when it considers it too weak, looks for a better alternative. Each manufacturer uses its own criteria, and many devices tend to stay where they are until the signal becomes really poor, because every switch involves a brief interruption.
This behaviour is sometimes called a "sticky client". The network can only suggest a switch or, in extreme cases, force it.
The three standards that help
Three extensions to the Wi-Fi standard were designed precisely to improve roaming. They work only if supported by both the access points and the device.
| Standard | What it does |
|---|---|
| 802.11k | The access point gives the device a list of nearby access points and their channels |
| 802.11v | The network can suggest that the device move to a better access point |
| 802.11r | Speeds up the handover by reducing the security key exchange |
802.11k: knowing where to go
Without 802.11k, a device that wants to change access point has to scan every channel to discover what is around. With the neighbour list, it already knows where to look and how far away each alternative is, so it decides sooner and better.
802.11v: a hint from the network
With 802.11v the access point can send the device a transition request towards another access point. The device remains free to ignore it, but many modern phones follow it. It is the gentlest way to correct a sticky client.
802.11r: a fast handover
With WPA2 or WPA3 every new association requires a key exchange that takes a moment. You do not notice it while browsing, but in a voice or video call it can cause a noticeable break. 802.11r, also known as Fast Transition, prepares the keys in advance and makes the handover almost instant.
There is a practical caveat, though: some old or cheap devices, especially smart home gadgets, handle 802.11r poorly and cannot connect to the network when it is enabled. If something stops working after you turn it on, it is the first suspect. One solution is to create a separate network without 802.11r for those devices.
Tuning access point power
A common mistake is setting every access point to maximum power. It seems logical, but it makes roaming worse: each access point is heard well even from far away, so the device has no reason to switch. Moreover the phone, which transmits at much lower power, hears the access point but cannot make itself heard well in return.
Reducing power, especially on the 5 GHz band, shrinks each access point's area and sharpens the boundary. The goal is moderate overlap: at transition points the device should see two access points with similar signals, not one very strong and one weak.
Minimum signal threshold
Many systems offer a minimum RSSI setting: when the signal received from a device drops below a threshold, the access point disconnects it, forcing it to look for another. It is effective but blunt: a threshold set too high causes constant disconnections at the edges of the house. Use it carefully and only after trying 802.11k and v.
A verification procedure
- Enable 802.11k and 802.11v on all access points, if available.
- Lower the 5 GHz power by one step and check coverage.
- Enable 802.11r and check for a few days that every device connects.
- Walk around the house during a video call and note whether and where it breaks up.
- Check in the management interface which access point the phone is connected to at different spots.
In my work this tuning, rather than adding more access points, is what solves most roaming problems in homes.
In short
- The device, not the network, decides when to change access point.
- 802.11k provides the neighbour list, 802.11v suggests the move, 802.11r speeds it up.
- Some old devices cannot cope with 802.11r: keep them on a separate network.
- Maximum power on every access point makes roaming worse.
- A minimum RSSI threshold is effective but should be used with care.
