Poor wireless roaming performance with Mitel 5624 Wi-Fi phones

[maximumboost]

We have 4 x Mitel 5624 Wi-Fi phones we're trialling at a customers site.
The site uses a D-Link DWC-2000 wireless controller + 149 D-Link DWL-8610AP access points.
Our problem is that we can't get the phones to seamlessly / fast roam between access points.
We removed all security from the voice SSID thinking security was the issue but that made no difference to the roaming performance.
We've tested every recommended wireless controller / WAP setting from multiple configuration guides for Aruba, Cisco, etc. but nothing has worked thus far.
The phone can take anywhere from 1 minute - 5 minutes to roam to a WAP outputting a better signal.
You can be standing directly in front of a WAP outputting a -30dbm signal and the phone will remain connected to a WAP outputting -80dbm.
Phones are running the latest firmware version 6.0.7

From our perspective it seems like the roaming algorithm in the phone is broken.
Anyone have any suggestions on how to improve the roaming functionality or experienced the same problem?

[Dogbreath]

I have a customer using these with Ruckus and doesn't have this problem. There may be a brief drop in audio, but nowhere near 1 minute.

[acejavelin]

Do the D-Link AP's support WMM-PS? We have seen large deployments that do not support it have issues similar to what you describe, the Mitel 5624 does not require it (like Spectralink) but will use it. Had to change out 30 Open Mesh AP's to Meraki because of it.

[maximumboost]

@Dogbreath - The voice stream doesn't drop for 60 seconds, it's the roaming process that can take over 60 seconds.
The 5624 phone hangs onto a WAP outputting signal at a strength of -80 to -85 dbm when you're standing directly under a WAP outputting signal at -30 to -40 dbm.
When the phone finally does roam you may get between 5 - 15 seconds of silence or garbled voice.

@acejavelin - U-APSD is turned on in the radio profile for the 2.4Ghz / 5Ghz radios which I believe is the same as WMM-PS.

[Gambler]

DogBreath - How do you have the phones configured to work on the Ruckus network?

[sunspark]

DogBreath - How do you have the phones configured to work on the Ruckus network?

i'm looking also to this information , if any one know if we need to use WMM PS or not .

[Dogbreath]

I am pretty sure WMM was on - I remember something finicky about the WLAN when setting this up. Unfortunately I can't give you any more detail as both the Ruckus and the MiVB in question were decommissioned and we've never deployed any 5624's [or Ruckus] since then.

[mark.vanderheijden]

Have seen cases where the SSID was hidden and giving roaming issue's

[sunspark]

But in hospitality environment you can't show ssid : wifi_5624 

[acejavelin]

But in hospitality environment you can't show ssid : wifi_5624 

Name isn't relevant... Give it a SSID like "housekeepingcarts", "hvacmonitor", "internalonly", or "NO INTERNET AVAILABLE" and no one will care it's there, or just use a random generator and call your SSID "eZzKr5&2WodQ%Y#" and use MAC address filtering if necessary.

[sunspark]

I'm not sure that's the source of the problem

[NEPhoneGuy]

Just saw a bulletin on these. FYI. The 5624s are going EoL and the 5634s are replacements.

[sunspark]

Just saw a bulletin on these. FYI. The 5624s are going EoL and the 5634s are replacements.

where did u find this information ?

[NEPhoneGuy]

InfoChannel from the Mitel portal. I think it's a mess but I try to look at it every few days because the front page there shows the latest stuff.

[sunspark]

Mitel announces manufacturing discontinuation and end-of-sales/end-of-life for the Mitel 5624 WiFi Handset
and the Mitel IP-DECT IPBS 432/442 base station products due to end-of-life components.
The products are replaced by new product introductions of Mitel 5634 WiFi Handset and Mitel IP-DECT IPBS
532/542 base stations