You may find some issues on Wi-Fi roaming when using a Deco system. Some of your wireless clients may fail to connect to the Deco Wi-Fi when the Fast Roaming feature is turned on. Some wireless clients sometimes roam to the remote Deco node although they’re just next to another node.

This story aims to explain the Wi-Fi roaming mechanism on a Deco system and help you understand the roaming behavior of your wireless clients.

Introduce of Wi-Fi roaming mechanism on Deco system

Several Deco nodes work together to form one mesh Wi-Fi network. Your wireless clients automatically connect to the Deco that provides the fastest speed as you move through your home, creating a truly seamless online experience. Support for IEEE 802.11k/v/r roaming protocols means switching from one Deco to another is so smooth that it’s unnoticeable, even during streaming and gaming.

1. 802.11k (Radio Resource Measurement)

With 802.11k, the Deco system periodically collects the information of the surrounding wireless environment and provide wireless clients with a list of nearby Deco nodes that are available to roam to. Neighbor Reports contain information about neighboring access points (APs) and help wireless clients quickly understand its surroundings.  

 

b. 802.11v (BSS Transition Management Frames)

With 802.11v, Deco will not only respond to Wi-Fi clients’ Neighbor Report request, but also evaluate the wireless connection quality.  When the current wireless connection quality is poor and there is a Deco node providing better wireless experience, Deco will recommend wireless clients to roam and prevent clients from sticking to a specific Deco node in most cases. Whether to roam is decided by clients and Deco just gives a roaming advice.

 

c. 802.11r (Fast BSS Transition)

To help wireless clients roam from one Deco to another on the same network, 802.11r has a feature called Fast Basic Service Set Transition (FT) to make the wireless authentication process more quickly. So, the time needed for a client that supports 802.11r to transition to another Deco is reduced. The 802.11r standard improves the connection quality especially for latency-sensitive applications, such as an active Skype call.

 

Note: 802.11k/v/r take effect only for wireless clients that support 802.11k/v/r as well.

If clients don’t support 802.11k/v, they won’t respond to 802.11k probe request so Deco will not guide them to roam and roaming can only be initiated by clients themselves. In this situation, clients may stick to the previous Deco.

 

If clients don’t support 802.11r, they may fail to connect to Deco. When the Fast Roaming feature is enabled in the Deco app, the wireless Beacon frames broadcast by Deco will carry 802.11r related information. Some clients can’t recognize this information and drop this Beacon frame, leading to connection failure.

Features involving 802.11 k/v/r in Deco app

Mesh Technology

Launch Deco app -> Tap “Internet” icon -> Select any Deco node -> You can see the individual Mesh Technology option for clients connected to this Deco.

Or you can Launch Deco app -> Tap specific device under online device list / Categories-> Click “Settings” button on the right upper corner-> You can see the Mesh Technology option for it.

Note: Not all Deco products have the toggle to turn on/off the Mesh Technology on the APP. For those Decos which we cannot find this toggle, the Mesh Technology is enabled by default. And this option will be added in the near future with the firmware upgrading.

 

The Mesh Technology option is the switch for 802.11k/v. With this feature enabled, the client can seamlessly switch to the Deco node that provides the fastest speed as you move around. Disable this feature only when you want to turn off seamless roaming between Decos for this client. After this option is disabled, roaming can only be initiated by the clients themselves.

 

Fast Roaming

Launch Deco app -> Tap “More” -> Tap “Advanced” -> Tap “Fast roaming”

Fast roaming with 802. 11r reduces authentication time and allows wireless clients to switch connection to different Deco nodes seamlessly.

Q & A

Q1: Why my clients fail to connect to Deco’s Wi-Fi network or disconnect from Deco’s Wi-Fi network when Fast Roaming is turning on?

 

Some wireless clients don’t support the 802.11r standard and couldn’t recognize the 802.11r related information in the Beacon frames broadcast by Deco either. In this case, you may find that these clients may fail to connect to Deco’s Wi-Fi network or disconnect from Deco’s Wi-Fi network after turning on the Fast Roaming feature.

If some of your clients have a Wi-Fi connection issue, it’s suggested to disable Fast Roaming for a try.

 

Q2: Why my clients roam to the Deco node farther away?  Why my clients don’t roam to the nearest Deco or roam slowly? 

 

The roaming behavior of wireless clients depends on several factors.

1. A Shorter distance does not mean a stronger signal.

Obstacles and wireless interference may affect the signal quality of the Deco units. You can get a better understand of the signal quality of surrounding APs via Wi-Fi analysis software such as Wi-Fi Analyzer.

2. It doesn’t reach the roaming threshold.

For AP steering, only when the signal strength of the current AP becomes lower than a threshold and the signal strength of another AP is good enough, Deco will recommend clients to roam via 802.11k/v.

3. The roaming behavior can vary depending on clients.

Deco can only provide a roaming suggestion. Whether to roam or not depends on the client itself as it has its own roaming threshold as well, which is decided by its manufacturer. In this case, clients may refuse the roaming suggestion or respond slowly causing the delay of roaming. There are also some clients that may decide to roam even though Deco doesn't recommend roaming.

 

If you want to stop your clients especially for stationary devices from roaming, you can try to disable the Mesh Technology option for these clients. Deco doesn’t support the feature to fix clients to specific Deco at present.

 

If your clients don’t roam to the nearest Deco, please check whether the roaming target provides much better signal strength. Please check whether your other clients also don’t roam under the same movement.

 

After you read this story and do some related tests, if you still think there is a problem with your client's roaming behavior, please kindly leave a comment.

 

Learn more about roaming standards from the IEEE website:

• IEEE Standard: 802.11k
• IEEE Standard: 802.11v
• IEEE Standard: 802.11r