Auto Hope between two different model APs

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Hi,
I have few Motorola AP 5131 and few Wing AP 7532. I have created same SSID under all APs Example SSID: WWMS-WiFi. 
I checked that my wireless device can auto hope as I walk in ware house. 
But at some point my devise keep connected to AP which is far than nearest AP.
Do you think auto hope can work between any two APs(Assuming Same SSID)?

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Ravi Patel

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Posted 2 weeks ago

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Chris Kelly, Employee

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Sounds like you're dealing with a 'sticky client' problem.  Not uncommon for certain wireless clients to do this.  The 7532, if it is using recent enough firmware, has some functionality that you can enable to help this issue.  It's called 'Roam Assist'.
The 5131 does not have this feature and there won't be much you can do on the 5131 to help with this issue.
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Ravi Patel

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Hi Chris,
Is that mean auto hope is only possible between two same model APs?
I have 5 motorola AP 5131 (which are pretty old) and newly installed 2 Wing AP 7532.
Do you think I should remove all AP 5131 and install AP 7532 or what is other possible solution?
At the beginning of buying AP 7532 i wasn't know about this thing.
Please advise.
Thank you
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Carlos Assunção

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If they are on the same subnet it should just fine. Except during roaming from 5131 to 7532 the devices shou authenticate again. But it should work fine.
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Chris Kelly, Employee

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Ravi, normally, you want to have APs from the same vendor to ensure proper communications between APs so that seamless roaming can happen.  But, even though the 5131 and 7532 are from the same vendor, they use different operating systems and will not communicate with each other.  You *will* be able to have the your wireless devices 'hop' between each of the 5131's, or between each of the 7532's, but if the client needs to hop from a 5131 to a 7532, the client will have to re-authenticate with the new AP as part of the hop.
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Aviv Kedem

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Hello Carlos,
IF you know what you are doing, it will work, but if not... it's not.
It's not officially supported configuration.

Regards

Aviv Kedem
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Carlos Assunção

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Hi, the authentication between roaming will happen , I have no doubt about that. But it will work even between different vendor. Got several projects with legacy access points and WiNG 5.X.
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Ravi Patel

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Hi Carlos,
Yes, you are right. my devices are able to hope between two different vendor APs but as you said it will re authenticate if it's different vendor AP. 
So, what exactly will happen in re authenticate ?
The issue i am facing here is my devices are auto disconnecting and auto connecting if its different vendor AP will come near by. Is this happening re authenticate?
Suppose I have all same APs then my devices should roaming between all APs and I will not have this re authenticate(dis connect & connect) issue. Is this right?
Thank you
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Chris Kelly, Employee

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Ravi, to be 100% clear, even if you have the same vendor APs and are using PSK, a wireless client will still have to re-authenticate every time it roams (generally takes about 40-60ms).  The only way to help this process is to enable one of the 'fast' type roaming protocols. (OKC, FT, PMK).

If you are just using pre-shared-key authentication (PSK), the roaming process is pretty quick.  It's normally not a problem and happens quickly enough that users don't notice.  

When this re-authentication CAN be a problem is when the client is using a time-sensitive application - like a voice call and using 802.1X authentication.  If it's using PSK instead (no 802.1X), this MIGHT NOT be a problem.  But if it's using 802.1X, and there's no fast roaming protocol being used, then most certainly the re-authentication process is going to be disruptive to the voice call.  The 802.1X authentication process will generally take 500-750ms...which is far too long a time to be acceptable for disruptive voice calls.  The majority of that time it taken by the during the .1X/EAP frame exchange.
(Edited)