Wireless: What is IEEE802.11r, IEEE802.11k, IEEE802.11v in SonicWave?
03/26/2020 9 8256
IEEE802.11r, IEEE802.11k, IEEE802.11v Settings
Why does roaming occur?
A Wi-Fi client will decide to roam to a new SonicWave (AP) when it detects a better signal from the new AP than the one it is currently associated with.
This behavior is normal, particularly when devices are moving around within an environment, such as laptops and mobile phones.
Why do clients face disconnectivity while roaming ?
Lets say we have two SonicPoints's in the network - SP1 and SP2 and a Client is connected to SP1.
When a client roams from this currently connected SP1 to the new SP2 it needs to re-establish an association/authentication request to that SP2.
In this situations the SPs are acting independent, this whole process must occur each time the client moves from one AP to another.
The client will disconnect from it's existing associated AP before connecting to the new one if 802.11k and 802.11r standards are not included.
Whenever a client roams it results in a time consuming period where the client has no network access. This can cause packet loss, dropped calls, or other negative performance.
How 802.11k, 802.11v and 802.11r help?
Both standards are equally capable of taking different measures to reduce the time required for a client to roam from one AP to another and reduce the roaming performance.
- 802.11k reduces the time required to roam by allowing the client to more quickly determine which AP it should roam to next and how. The SonicWave to which the client is connected will provide information regarding neighboring APs and their channels. Using this mechanism when the client is ready to roam, it has a better idea of where it will be roaming.
- 802.11v allows client devices to exchange information about the network topology, including information about the RF environment, making each client network aware of the environment, this helps overall improvement of the wireless network.
- 802.11r uses Fast Basic Service Set Transition (FT) to allow encryption keys (eg. PMK, PTK, GMK, GTK) to be stored on all of the APs in a network. Using this, a client does not need to perform the complete authentication process to the server every time it roams to a new AP within the network. Thus avoids a significant latency issues and packet loss.