These Wi-Fi Retry Percentages Are Too Dang High (no really... Retry% statistics are often inaccurate)
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...