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Community Member

77920 roaming problem

I have noticed that when my 7920 is roaming, it looses connection with the AP.

My AP has the very basic config, open authentication with a wep key on the SSID for voice and data vlan. I also have qos configured and applied.

I have read in this forum that there should be a 20% overlap for voice. How do I check my wireless signal overlap percentage?

Also when it comes to the channels, should all my ap be configured with the same channel for voice?

Can any one please tell me or point me in the direction for best practice in deploying 7920 with 1230 ap?


Community Member

Re: 77920 roaming problem

If you have AP version 12.3(4)JA or higher, then you need 1.09 firmware or higher on the 7920 or roaming will not work. For site survey, should use non-overlapping channels (i.e. 1,6,11). Ideally would like to roam to a non-overlapping channel (i.e. 1 to 6 or 11). Can easily just use 7920 and ensure you have signal of 30 or higher for both APs where they overlap.

Refer to the design guide for more info.

Community Member

Re: 77920 roaming problem

Thanks for your response. So if I use non overlapping channels 1,6,11 and I have eight access point in the building. Does that mean I will have two or more access points using the same channel?

What about the other channels, can I use those with the 7920. I will make sure I have firmware 1.09 or higher.

Also what option allows me to strengthen or weaken the signal of the access point?

I have read that signals between AP for 7920 deployment should overlap at least 20%. How do i determine how much percentage my access point her overlapping?


Community Member

Re: 77920 roaming problem

Yes. Should only use non-overlapping channels even though you have more than 3 APs. 7920 gives precedence to discovered non-overlapping channels.

Recommend 2.01 sw for 7920. Just need to ensure that you tune your network for 11mbps and you have -67dbm of signal always w/ 25db SNR. For adequate overlap, you can either just walk around and ensure you have RSSI of 30 or higher where the 2 APs overlap or you can use tools such as Airmagnet Surveyor (

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