Client Roaming - drop connections if connection is not reliable

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  • Updated 3 years ago
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Hi,

Is there an option to force "client roaming" if the RSSI is bad? So that the connection drops and client authenticates to another AP (if it's availble?)
I want setup this behaviour that clients disconnect at a RSSI of -85 dBm because we see some issues when clients or on the edge of coverage of different AP's.
This also helps with sticky clients...mostly scanners which can work on lower data rates. (non dense deployment).

I know Cisco has such setting => http://ccie-or-null.net/2011/05/16/control-roaming-wlc/

Any advice?
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Aart Kenens

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Posted 3 years ago

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John Fabry

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It depends on the client.  Apple does not have the option.  They will not roam until -75 to -80.  This is to extend battery life. Almost every other manufacturer has some type of setting. It may be by db or y generic setting,  aggressive roaming or not. The recommendation from Apple is to set the radio TX power as low as you can and add APs if needed for coverage. For the other manufacturers you just need to do your research to see what the client is capable of. Sorry.
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J. Goodnough, Champ

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apple wireless roaming info:

https://support.apple.com/en-us/HT203068
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Mike Kouri, Official Rep

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John's advice is good, another thought is to disallow the lower data rates. I believe most Aerohive Systems Engineers generally advise customers to disallow data rates below 11MBps, and sometimes even higher, depending on the density of the APs.
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Aart Kenens

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Yes, I also thought about cutting down data rates but we got motorola/psion terminals which need to have the 1/2 mbps rates. (according motorola)
These terminals are just telnet clients but the problem we experience is that we need to scan the goods outside and we have an unusual outside storage place.

In our case making the outside wifi environment more dense will increase costs but I think we will have too much channel overlaps creating other problems as some spaces are wide open (200m).

But this is not the issue, the issue is that the terminal (Psion Omnni XT15) doesn't roam properly when the environment isn't dense enough. Their algorithm for roaming doesn't make sense when you've sometimes bad coverage. Those terminals get sticky and Motorola WIFI and Cisco controllers can help with client roaming.
I must say the client doesn't have roaming issues if the RSSI stays under +- -70/75dBm.(dunno about SNR)
Our MC9090 handhelds doesn't have those roaming issues like the XT15's.

So in cases like ours where the client doesn't have a good roaming algorithm(or a flaky one) such setting/feature will help if we could enable it on a SSID.
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Metka Dragos

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Aart,
did you try the SNR settings in radio profile? I know you say that you do not know the SNR, but odds are high that if RSSI is low that SNR will be low too

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Aart Kenens

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Hi Metka,

Yes I am aware of this setting and this has been enabled for a test but it didn't help.
I think this is only to prevent connecting/probing clients who have a bad SNR?
If so that wouldn't solve my terminal getting dropped from the current connection if it has a bad SNR?
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Aart Kenens

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@Mike Kouri, can this feature or setting be placed on the roadmap? I see use in it.