Sniff Wi-Fi

Your humble author is starting a new Sniff Wi-Fi blog series today: Bad Security Stories Yours truly may not be the second coming of Bruce Schneier -- though from what I've read of Schneier's I like his vibe -- but all these years of sniffing (and working in Wi-Fi in general) have led to me picking up a fundamental understanding of communications and data security. So let's blog about it! A  college football cheating scandal -- or at least, the potential for one -- was recently uncovered and resolved in a matter of three days . To steal a quote from a memorable-but-not-to-be-described-in-polite-company scene in the film Tommy Boy... hmm, that's a mystery. A quick primer: Throughout last year's college football season, there were several accusations of 'sign-stealing'. Sign-stealing involves comparing the hand signals, posters and other 'signs' used by football coaches to signal to their players what formation and/or orchestrated 'play' to ru...

  Show  of hands: Who here has seen Retry percentages above 90%? If you work with Wi-Fi, your arm is likely reaching skyward as if you're hiding Darrell Lea licorice from the kids. (Hope you wore deodorant today.) Juniper Mist is most notorious for it. Nyansa Voyance -- which is no longer a Wi-Fi thing -- used to do it too. Aruba Central even has a built-in alert for it. The problem is, 90% retries doesn't really exist (and of course, 100+% retries is impossible). When an AP repeatedly sends retransmitted frames (packets) to a Wi-Fi client -- and let's pause to point out that centralized WLAN management systems can only reliably know AP-to-client (not client-to-AP) retry statistics -- the AP will typically drop a packet before re-sending it so  many times that the wireless retry percentage would ever truly hit 90%. So why, then, do we see retry percentage near, at or above 90%? Because some (most?) Retry% calculations often use a denominator of successful  frames in...