Issues with handoff E400

I'm using 3 e400s in a single floor office building. I have 2 wireless networks setup using different vlans. One for guest access and another for secured office access. 

The wireless network name is the same on all three devices, but I'm not using MESH. In the past with my cisco APs, when the signal was stronger the client's device would switch to the new AP. However, that doesn't appear to be happening with the e400s. At times the devices will stay connected to the AP with a poorer connection causing slowness.

This primarily occurs when a user goes from there desk, to a conference room. The laptop will hold the connection from the desk area and not pick up the new stronger signal in the conference room. This can be remedied by disconnecting, and reconnecting manually, but I'd like to get this setup automatically. 

Any help would be greatly appreciated. 

Hello, unfortunately it is entirely up to the wireless client when it comes to roaming, and it could vary widely between different device chips/types.  Manufacturers build in some features to help clients roam efficiently, such as 'Enhanced Roaming' and data rate pruning, but nothing replaces a good wireless design.  I would hesitate on using enhanced roaming unless you have a good idea of the coverage pattern of your wireless install.  It could cause more harm than good if you don't have enough coverage for all of the different wireless client types.  A laptop will typically have a stronger connection because of the number of antennas (2x2 or 3x3 MIMO), versus a smart phone or older device (1x1 SISO), but there are variations even within the same manufacturer.

Laptops in particular are notoriously 'sticky,' meaning they will hang on to the AP until the connection is very poor (early iPADs also had this issue).  The easiest 'fix' for your situation is to change the roaming aggressiveness on your laptop's wireless card (go to the actual adapter properties>advanced and change roaming aggressiveness to highest).  I would also change the preferred band to 5GHz and enable band steering on the AP.  5GHz coverage is typically less than 2.4GHz and may help push the client to roam.

I've attached a presentation that I've done for Telco's, MSP's and WISP's that may help with your wireless design. It is vendor agnostic, and is getting a bit old, but is updated for 802.11ac wave 2. It is all about giving the wireless client the best environment to make the best decision on how to connect to the AP.

There are also useful third party tools, such as AirMagnet, that can help with the predictive design (and verification of the install) in order to ensure that you have just the right coverage for the area and application.  Too much power/coverage is not always the answer.

Some changes to the AP configuration that may be beneficial:

- limit 2.4GHz bands to g/n/ac (or just n/ac if you have newer devices)

- lower 2.4GHz Tx power to 27 dBm (or 24 dBm)

- limit channel selection for 2.4GHz to 1, 6, 11 (potentially just 20MHz channels if more than 2 APs)

- enable band steering (potentially up to aggressive) if you have dual band clients

- verify channel plan and use the interference avoidance settings to automatically change channels if interference is detected.

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Have you tried enabling a roaming SnR threshold cut off on all your AP's?

I have not tried the roaming SnR threshold. Is 10 the recommendation?

I'll also try all the settings you suggested Eric. 

10 is probably a safe bet, but it is all dependent on what the current coverage and overlap look like.  Also, the wireless client may still try to go back to the poor AP, depending on the algorithm used in the driver.  I would use it more as a last resort.  More information on Enhanced Roaming here.

What I would suggest is taking a look at the SNR reported by the client at the point that you think it should have roamed to the other AP.  You can use the wireless adapter on the device, or cnMaestro, or a free Wi-Fi utility.  That will be a good indicator of threshold.

However, this may cause disruption of other clients, so you may need a larger sampling of wireless clients to ensure that the value being used isn't going to adversely affect your design in general.  Take a look at the attached, but if you have a smallish number of laptops, I would see if you can change the adapter settings first.

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