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How to Fix a Cisco Wi-Fi Network Without Surveying, Adding APs or Moving APs

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The vast majority of Cisco Wi-Fi networks can be fixed without having to spend precious time and money on surveying, adding new access points (APs) or moving existing APs.  Here's how.

Cisco has some very fine enterprise Wi-Fi products.  Unfortunately, those very fine products often get deployed in a manner that leads to connectivity and performance issues.

The following steps take about ten minutes to perform, and will stabilize connectivity and performance for the vast majority of enterprise-class Cisco Wi-Fi networks.  Anything in bold is something to click or select or check or uncheck or type.

1. Access the Cisco wireless LAN controller (WLC) interface via a web browser.

2. Navigate to WLANs (menu) -> -> Security (tab) -> Uncheck WPA Policy -> Apply

NOTE: Wi-Fi Protected Access (WPA) is a Wi-Fi security method that uses temporal key integrity protocol (TKIP) encryption by default.  Using TKIP encryption disables 802.11n and 802.11ac data rates, effectively renderin…

Channel 13, F*#k Yeah!

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Wi-Fi is a technology used around the world and we, as Americans, respect all cultures and creeds.  That said, occasionally we like to celebrate ourselves (NSFW, as if the title didn't make it obvious):



Unfortunately, America has been behind the times in Wi-Fi.  No longer!  We now have motherf*#king 2.4 GHz channels 12 and 13.

This blog has a rigid rule to avoid politics, so I'll phrase this as apolitically as I possibly can: from January 20, 2009 to January 19, 2016, America's wireless authority -- the Federal Communications Commission (FCC) -- repeatedly authored rules that damaged Wi-Fi.  In 2010 the FCC banned Wi-Fi on channels 120 through 128, in 2014 the FCC messed up channels 52 through 144 by requiring additional dynamic frequency selection (DFS) scanning and in 2016 the FCC declined a proposal by satellite phone provider Globalstar to allow 2.4 GHz channels 12 and 13 to be used for "terrestrial, low power services" (TLPS), which just so happen to have the…

In Search of an Accurate Site Survey

This week's big Wi-Fi news was Ekahau's introduction of the Sidekick, an easy-to-carry, laptop battery-conserving device designed to make Wi-Fi site surveying more elegant.  Unfortunately, it appears to do more to exacerbate Wi-Fi problems than to solve them.

What is the number one problem in enterprise Wi-Fi?

It surely can't be security.  Security is a hot topic, but Wi-Fi security isn't really a problem anymore.  Even security problems that Wi-Fi gets blamed on -- Pineapple hijacking, Wi-Phishing, man-in-the-middle -- either aren't problems for modern devices & applications, or are problems that extend beyond Wi-Fi.

Maybe it's user density?  Or supporting a variety of devices?  Maybe it's connection issues; when moving or when the device is idle for too long?

Whatever the answer, chances are it comes down to one overarching issue: different Wi-Fi devices behave differently.  Capacity testing gets done using laptops, then smartphones cause the Wi-Fi to…

Eka-Heka-Hau Eka-Hiney-Ho or: Jussi's Big Adventure

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There are times in life when I feel like I've been misunderstood, and I would like to just wish away the communication gap. 

Unfortunately, there is no Wi-Fi Jambi, so instead I am going to use this short blog post to try to smooth things over with Jussi Kiviniemi, SVP of Ekahau.

For those who are unfamiliar, Ekahau is site survey software.  You can do predictive surveying (sometimes called "planning") with it and you can do live surveying (the "walking survey") with it.  Either way, the result is a nice looking "heat map" showing Wi-Fi coverage over your floorplans, like so:


Jussi Kiviniemi is the public face of Ekahau.  He's a Finnish guy and he goes to Wi-Fi conferences, hosts events, is active on Twitter, etc.

There are days when I think that Jussi doesn't like me.  And being the rugged, pro-American American that I am, I take responsibility for things that happen to me.

The root of Jussi's occasional distaste for me -- I think; I supp…

Ghost Frame Killah

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Recommending the exact opposite of what every enterprise Wi-Fi infrastructure vendor recommends can be awkward.  As awkward as the first meeting between Hank Kingsley (Jeffrey Tambor) and the Wu-Tang Clan?  (WARNING: extremely NSFW)


Maybe not that awkward.  
But while Hank had trouble relating to Wu-Tang member Ghostface Killah, Wi-Fi folks can avoid trouble by being aware of an increasingly common problem, the Ghost Frame Killah.
Ghosts, as we all are well aware, are apparitions that can have a detrimental effect on buildings built on Indian burial grounds, while remaining unseen to our earthly eyes.  If you have Ghosts, you may need to call a Ghost Bouncer to solve the problem.
Ghost Frames, on the other hand, are Wi-Fi frames ("packets") that can have a detrimental effect on Wi-Fi networks, while remaining unseen to our earthly Wi-Fi sniffing tools.  The solution to Ghost Frames is a simple one, but one that requires Wi-Fi folks to do the exact opposite of what enterprise W…

Cisco Gets a Case of Throughputitis

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Far be it from me to hate on a Wi-Fi vendor...

...but seeing Cisco's Wi-Fi recommendations for iPhones (and other Apple iOS devices) has led me to wonder whether The Cisco (Kid) is a Friend of Mine.
Cisco released a Best Practices doc for supporting iPhones, iPads, et al. back in November.  For whatever reason I missed it back then.  I'm bringing it up now because Keith Parsons had something about it on his Twitter feed and Ekahau has a webinar coming up on designing a Wi-Fi network for iOS devices.  
I am happy that Cisco is bringing up the topic of device-centric Wi-Fi design.  Wi-Fi is (or, at least, should be) all about the end user, and device-centric design implicitly acknowledges this.
I am less happy at several of Cisco's actual recommendations.  They seem to have fallen into the trap of believing (or, more perhaps more accurately, leading) the Latest Trendy Wi-Fi Disease, throughputitis.  
Throughputitis, as you all know, is Latin for "inflammation of the throu…

Assess Yourself

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Yo, man.  There's a lot of Wi-Fi installers out there flakin' and perpetratin', but scared to kick reality...
So what you want Wi-Fi engineers and admins to do?
Assess Yourself!  


To which you might respond, "Duh!"
Any networking or Wi-Fi person worth a lick knows that a network should be assessed before (and, in many cases, after) deployment.  What is far, far, far less well known is HOW to assess a Wi-Fi installation.  
Properly assessing a Wi-Fi installation involves two parts: assessing configuration settings and assessing the physical location of access points (APs) and antennas.  And if you don't assess both, you'll be making a sucker and you equal
While rolling through the streets of Searcy, AR in my main man GT Hill's 1984 Ferrari convertible, I was given some wise insight.  Not, "I only buy things that make money back," a former favorite quote of GT's prior to the purchase of said Ferrari.  Instead, it was wisdom about churches, whi…