Sniff Wi-Fi

Last week's blog about Wasted Wi-Fi prompted some questions about AP transmit power in the enterprise.   Let's answer some of those questions by doing a little Q(-Tip)&(802.11)A, an exercise in which we watch a Q-Tip video before Answering a few questions about Wi-Fi. You've seen the Q(-Tip), now on to the A(nswer)s: Wasted Wi-Fi is all about APs and/or stations making inefficient use of a Wi-Fi channel.  When Wasted Wi-Fi happens, either data rates are lower than they should be, or Retry percentages are higher than they should be. The Q becomes, where do equivalent isotropically radiated power (EIRP), transmit power and conducted power fit in? The A is, higher data rates and lower Retry percentages tend to happen when signal-to-noise ratio (SNR) is higher, and higher EIRP/conducted power/transmit power leads to higher SNR. In other words, if you talk louder, then people hear louder.  When people hear louder, they have a better chance of being able t

Apparently Wi-Fi at the White House sucks !  A journalist asked me what might help it, so I figure I'll share my response: Hi [Very Wise Journalist Who Reached Out To Me, Ben Miller, For Comment], In some ways the White House is like any other large, multi-user space and in other ways it is very different. Uncommon challenges at the White House are likely the result of security requirements and the need to maintain the historical integrity of the building.  The White House almost certainly has areas that are off-limits to AP installers and there may be limits on where cable drops can be made. There is a distinct line between good and bad solutions when AP locations are restricted.  The goal of both solutions is to increase coverage to hard-to-reach areas.  The bad solution, which is likely happening at the White House, is to increase the transmit power of APs.  Increasing AP transmit power aids downlink data sent from an AP to a Wi-Fi device, but does nothing to impr

I have some interesting stuff about the topic that this blog is supposed to be about (WiFi sniffing) coming soon.  I promise.  But the FCC made some news concerning WiFi today, and I want to help people understand it. This post is happening because of what the FCC did in March, 2014.  What the FCC actually did was (probably) kill WiFi channels 52 to 144 by imposing new rules (the effects of which we have yet to see, because APs approved by the FCC prior to March, 2014 do not have to follow the new rules) that make WiFi devices more likely to work poorly when Doppler RADAR is on those channels.  What the FCC claimed they did was " increase availability of spectrum for high speed, high capacity " WiFi. Technically, the FCC can claim to be something other than liars.  The March, 2014 rules did increase spectrum availability in a narrow sample of use cases.  What was really going on, however, was the FCC doing the bidding of Doppler RADAR operators (who, possibly-not-so-coi