topic Security-risk Interferer 'WiFi Inverted' is detected. in Wireless

Security-risk Interferer 'WiFi Inverted' is detected.

thomas03usmcsf — Sun, 04 Jul 2021 03:50:45 GMT

Anyone have any solid information on this warning? I found a few things online, but nothing great. Thanks.

Security-risk Interferer 'WiFi Inverted' is detected.

Nicolas Darchis — Fri, 30 Sep 2011 06:58:52 GMT

Actually, spectrally inverted is swapping the I and Q arms of the signal.

   I(n)' = Q(n);

   Q(n)' = I(n);

That just looks like noise to any WIFI chip, other than for Long Preamble 11b.

Inverted: I/Q (in-phase/quadrature) modulation is inverted, compared to the 
802.11 spec

Security-risk Interferer 'WiFi Inverted' is detected.

patoberli — Wed, 23 Nov 2011 11:41:18 GMT

Do you maybe have more information about this?

I receive that alarm around 10-30 times a day on our campus. WCS treats this alarm with a Severity of Critical and thus I receive the email. But the email does not really contain any details.

Is there a way to troubleshoot this issue on the controllers?

Is there a way to found out which controller raised the alarm?

The alarm usualy goes away after 1-2 minutes.

Security-risk Interferer 'WiFi Inverted' is detected.

patoberli — Mon, 20 Feb 2012 08:39:04 GMT

Hi (small update)

We also have still quite a few of those messages. Running Controller 7.0.230.0 and WCS 7.0.230.0 and many 3500 and 1142 APs.

I once checked a few of those alerts and they seemed to come from old iPhones 3G running a 3.x iOS release. Might be a software issue on those models. But that is just a guess on my side. I haven't invested all that much time into it.

Have you got any more information about this, or are we the only ones receiving this kind of errors?

Security-risk Interferer 'WiFi Inverted' is detected.

Stephen Rodriguez — Mon, 20 Feb 2012 13:48:04 GMT

take a look at this previous thread.

https://supportforums.cisco.com/message/3460743#3460743

Steve

Security-risk Interferer 'WiFi Inverted' is detected.

sro — Fri, 24 Feb 2012 11:54:19 GMT

Hi patoberli

I have a customer with the same problem. Every day he got also about 20 "security risk "WIFI Inverted" is detected" per day.My customer has many 3502 APs, and the wism i running 7.0.116.

I have tried to find the inverted WIFI, with my spectrum expert card. I can see the inverted WIFI with spectrum expert, but I was not able to find them physically. After 1-2 minutes they disapeer again.

So I see a semilar problem like you patoberli.

You wrote that it possible was and old iPhone 3G with IOS 3.x. Have you invested more time into this ?

I hope to here from you 🙂

Soren

Security-risk Interferer 'WiFi Inverted' is detected.

patoberli — Fri, 24 Feb 2012 12:46:30 GMT

Hi Soren

No I haven't spent anymore time. I actually don't even remember how I found the Macaddress of those "Inverted Wifi" devices. But like you, they disappear after some seconds/minutes and thus I don't really care.

pato

Security-risk Interferer 'WiFi Inverted' is detected.

Mark Lancaster — Wed, 30 Jan 2013 17:55:23 GMT

Updating this older thread with some info. I was running spectrum expert around a new 3500 AP, and I noticed "WiFi Inverted" signals detected when the AP was in monitor or Spectrum Expert mode.