What is WiFi Roaming and how to use it on VigorAP?
Wireless roaming is when a wireless client(station) moves around in an area with multiple access point(AP), it may automatically switch to another AP which has better signal strength.
However, the wireless signal handover is a decision of the wireless clients, and we often find the wireless clients stick to the original connected AP which has weak wireless signal but don't roam to the AP with the stronger signal.
AP Assisted Roaming
VigorAP provide "AP-assisted Client Roaming" which could assist the wireless clients to roam more effectively. Network administrator could set up conditions related to RSSI or Link rate for AP to kick out the wireless clients with poor signal, and help the "sticky" wireless clients transfer to the optimized
Configuring on VigorAP
1. To enable wireless roaming in the network, the APs must have the same SSID and use the same security mode and password phrase.
2. Channel on each AP does not have to be the same, actually, it is recommended to use different and non-overlapping channels for each AP to avoid interference between them.
3. After preparing the SSID, go to Wireless LAN >> Roaming and set up the parameters.
- Minimum Basic Rate
AP will immediately disconnect the wireless client whose link speed (Mbps) is lower than the minimum rate.
- Strictly Minimum RSSI
AP will immediately disconnect the wireless client whose RSSI(-dBm) is lower than the minimum RSSI.
- Minimum RSSI with Adjacent AP RSSI over
If the wireless client 's RSSI(-dBm) is lower than the minimum RSSI, and there is another VigorAP on the network, which has a signal with the wireless client stronger enough (RSSI is higher than current RSSI, and the difference is over the defined value), only then will the AP disconnect the wireless client. This mode requires information exchange between the APs, so it will work only when all the AP are VigorAP that supports this feature, and are connected by Ethernet and under the same LAN subnet.
Note: Basic Rate and RSSI Requirement can be enabled at the same time, AP will disconnect the wireless client once it meets one of the conditions.
Network administrator could check the wireless client information such as Link Speed and RSSI from Wireless LAN >> Station List
How to improve client handover between AP
1. Network adapter settings on stations:
Some wireless network adapter support Roaming-Aggressive feature which could be found on Device Manager > Wireless network adapter (Right Click) > Properties > Advanced. Client could change Roaming-Aggressiveness value to Highest
2. Wi-Fi roaming on Android, we can see the signal strength on Android.
Go to Developer Options>> WiFi Verbose logging.
Then we can check the Wifi RSSI(-dBm).
Network administrator could also check the "kick off" message in the Diagnostics >> Syslog Explorer. The message means AP had disconnected the wireless client because of AP-assisted roaming settings.