6

Does Android support the 802.11 specifications that allow fast roaming, i.e. prevent dropouts as you move between access points? If so, on what hardware and in what version?

802.11k assists the device in its search for nearby APs that are available as roaming targets by creating an optimised list of channels. When the signal strength of the current AP weakens, device will scan for target APs from this list.

802.11r authenticates more quickly through Fast Basic Service Set Transition (FT).

802.11v allows the network’s control layer to influence client roaming behaviour by providing it the load information of nearby access points. Device takes this "BSS transition management" information into account when deciding among the possible roam targets.

Apple's iOS does, as documented here and here. Windows 10 does if the WiFi adapter supports it as documented here and here (suspect latter is currently out of date with respect to PSK & open networks).

Some Samsung models do, as documented here.

But I can't find anything on stock Android (Google Pixel).

2
  • Looks like at least Samsung supports that for several devices (listed there) as part of their Knox. Android Source Code at least mentions 802.11k, also R (#2296) and v (#1595) – so I'd guess the answer is "Yes" – if the hardware supports it.
    – Izzy
    Aug 9, 2018 at 15:53
  • I think regardless of whether Android supports this or not, the drivers/modules for the WiFi hardware, and the hardware itself, must be capable of supporting these standard protocols, and this is not just about the Android OS being capable.
    – acejavelin
    Aug 9, 2018 at 16:01

2 Answers 2

2

Each of those amendments you listed above include a collection of methods/mechanisms/features that have been incorporated into the IEEE 802.11 standard to achieve particular goals/improvements. Whether or not these are supported on a device will depend on the following:

  1. Specific feature/mechanism
  2. Android version
  3. Device vendor implementation and drivers

Also, keep in mind that in order for these features to work, they not only need to be supported on the client device but also supported and enabled at the infrastructure level (e.g. access points).

Another thing specific to 802.11r (FT) is that it will improve transition times when using 802.1X/EAP (WPA-Enterprise) security. On a preshared key (WPA-Personal) network, the difference will be negligible at best.

Last but not least, even if all those mechanisms are supported and enabled you could still experience roaming issues. That's because a wireless network needs to be designed at Layer 1 (RF) so as to provide for a good roaming experience, among other things.


These could be of help:

Crowdsourced client device 11v support list: https://clients.mikealbano.com/home

More info about WLAN roaming: https://community.ubnt.com/t5/UniFi-Wireless/Wireless-LAN-Roaming-FAQ/m-p/1825118

2

Having now created 802.11r, k & v infrastructure firstly with Unifi and then OpenWRT, I can now say definitively that at least the Google Pixel 6 running Android 12 does. I can walk from one side of my house to the other without dropping a WhatsApp/WiFi Calling/Teams/Skype call.

Based on my experience, OpenWRT is the best way to get to this point but have to say that it has been tricky. The advantage of open source vs. Ubiquiti shenanigans; not needing a controller; and having freedom of choice wrt cost-competitive equipment (BT Home Hub 5A, Xiaomi 4A Gigabit edition) and the control outweighs the more challenging & less guided learning curve.

The biggest benefit for me came from Fast Transition (802.11r). Note that this does not (yet?) work for WPA3. And that WPA2-PSK allows "Over the DS" in addition to "Over the Air", as each access point can derive the required required PMKR1 on its own (i.e. without non-standardised CAPWAP communication). Although Andrew McHale's 802.11k/r/v testing concludes this isn't as good as logic might suggest.

Neighbourhood Reporting (802.11k) must be helpful but I can't say that I really notice the additional benefit and does require some interAP communication or careful configuration to set up. I found https://github.com/simonyiszk/openwrt-rrm-nr-distributor very useful and instructive.

802.11v reports as working, but the benefit at least in my scenario is not at all clear.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .