FreedomBox for Communities/Wi-Fi Roaming

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Community could be spread over a large area such an entire village or an educational institution. If there are multiple Wi-Fi access points with different names, users will have to know and provide password for each of these networks. To avoid this, it is desirable for the entire community to have a single Wi-Fi network name called SSID. When a user is connected to the nearest Wi-Fi account point and then moves such that they are out of the range of that access point and in range of another access point, we wish that the transition to be smooth. Existing connections should not break. User should not see a drop in Wi-Fi connection. User should not be promoted for a new password. This is known as Wi-Fi roaming and is commonly deployed in large area Wi-Fi networks such as campuses.

Access Point[edit]

Wi-Fi roaming is simple to implement on the access point side. The following conditions must be met:

  • Each of the Wi-Fi access points in the network must be configured to have the same SSID.
  • Each access point must be configured not to provide IP addresses on their own but instead relay any requests from clients in the Wi-Fi network to servers in the back-haul network. This can be achieved on the most Wi-Fi access points by configuring them in repeater mode.
  • Have a single entity on the LAN (back-haul network that connects all access points) provide DHCP addresses to all the agents. In case of community setups with FreedomBox, the FreedomBox server performs this task. See section on configuring FreedomBox network.

Client[edit]

Wi-Fi roaming on the client side is where all the magic is. They need to keep scanning for access points. When a user moves closes to an access point with a better signal (either more strength or better signal-to-noise ratio), they switch to that access point. Since clients store a given password in relation to an SSID, if the SSID of the new network is the same as the old one, the client will try to connect to it with the same password as the earlier network. Well implemented clients behave better than others. So, Wi-Fi roaming experience is dependent on the client. Most mobile devices are expected to work well.

Testing[edit]

Use an Mobile application that shows the signal strength, SSID, connected access point and channel number of Wi-Fi networks in the area. Connect to the network and roam around to move away to a better access point. You should see a switch from one channel to another channel.