Sniff Wi-Fi

At the 2018 Wireless LAN Professional Conference (WLPC), I was scheduled to give a ten-minute "Ten Talk" on Wi-Fi surveying without using site survey software.  I aborted that talk at the last minute in favor of a talk on Ghost Frames .   After the WLPC, Matthew Norwood told me on Twitter that he was looking forward to the talk about surveying without using site survey software.  I don't want to disappoint Matthew, or anyone else who was looking forward to that scheduled Ten Talk.  Here, then, is a YouTube version of the aborted talk on Wi-Fi surveying without using site survey software: ****** If you like my blog, you can support it by shopping through my  Amazon  link or becoming a Patron on  Patreon .  Thank you. Twitter:  @Ben_SniffWiFi ben at sniffwifi dot com

The recently completed Wireless LAN Professionals Conference (WLPC) was nice enough to gift attendees a Wi-Fi Stand .  The product is a clever one, but as a person who believes in measuring Wi-Fi propagation accurately when surveying, I was concerned.  When I tested it, my results showed that my concerns appear to be unfounded. The Wi-Fi stand is an apparatus that screws in to the top of a tripod to make a vertical, rectangular structure that allows enterprise APs to be hung upside down from standard ceiling mounts.  If that is a little bit hard to visualize, here's my best shot at describing it: The graphic on the left is what the Wi-Fi Stand looks like and the graphic on the right is how the Wi-Fi Stand looks on top of a tripod. I am a big believer in designing & surveying Wi-Fi using real, production devices, and a longstanding problem with that has been temporarily mounting APs for the design/survey.  I've tried zip ties, and velcro.  I've gone...

If I sound a little bit surly today, it's because I spent last night watching this: For those who don't follow basketball, that's the brilliant Nikola Jokic (likely named in honor of wireless pioneer Nikola Tesla !) dissecting my beloved Milwaukee Bucks . If the result of the game -- the Bucks losing by 11 points in Milwaukee -- didn't make me surly on its own, my Wi-Fi experience yesterday surely didn't help.  The Wi-Fi in the Southwest Airlines terminal at LAX was slow and unstable, and the Wi-Fi at the aforementioned game (held at the 18,717 capacity Bradley Center) was mostly unusable in the seating bowl.  But what good does it do to stay surly?  Instead, I'll offer some tips on getting Wi-Fi working at high occupancy spaces. High occupancy Wi-Fi is a sensitive issue for me for two reasons: 1) I'm sick of fixing high occupancy deployments, and 2) As a frequenter of high occupancy areas, I'm sick of bad Wi-Fi in those areas. The trouble i...

Device vendor secrecy makes Wi-Fi worse for users. "Wi-Fi is all about the users."  It's my Pinned Tweet  and my professional operating philosophy.  I don't care about AP vendor preference or network management or heatmaps or anything else that doesn't improve the user experience.  I want every device for every user to work everywhere at all times, period.  That's the goal. It is frustrating to me, therefore, that Wi-Fi device makers are so tight with their information.  I've gotten a lot of blowback for my writing and Tweeting about what a mistake it is to set the Minimum Basic Rate (MBR) above 6 Mbps .  Most of it is balderdash from BS artists and other people who don't know Wi-Fi.  A not insignificant amount, however, is from people who know Wi-Fi, at least to some degree.  And the common refrain from those people can be summarized thusly: "Wi-Fi devices use more than just RSSI to determine when to roam."  Maybe things h...

One of my favorite things to do is teach Wi-Fi, and one of my favorite tools for teaching is Savvius  OmniPeek .  The good folks at Savvius were nice enough to provide OmniPeek for the Wi-Fi classes I oversee at Global Knowledge , and so I want to offer a taste of how OmniPeek can be used to learn about Wi-Fi device behavior, specifically with the iPhone X. Savvius OmniPeek is what I call a hardcore protocol analyzer.  The "hardcore" adjective comes from the fact that OmniPeek encourages the user to view frame (aka "packet") traces.  Non-hardcore protocol analyzers focus on providing statistics and graphs.  I am a big fan of all types of protocol analyzers, but the beauty of OmniPeek is that it offers options for viewing statistics and graphs, while making its frame traces simple to navigate. One of the things I like using OmniPeek for when teaching is illustrating the different ways that Wi-Fi devices and APs use the 802.11 standard.  An example is wh...

The Wi-Fi Alliance announced its next security enhancement today, called WPA3.  The press release touts "four new capabilities", but only one of the four affects practical Wi-Fi security. As they are occasionally wont to do, the Wi-Fi Alliance  announced a new certification today via a press release featuring an artisnal blend of normal words and corporate gobbledygook.  For those who speak fluent corporate gobbledygook, here are the four enhancements of WPA3 : Robust protections even when users choose passwords that fall short of typical complexity recommendations. Simplify the process of configuring security for devices that have limited or no display interface. Strengthen user privacy in open networks through individualized data encryption. A 192-bit security suite, aligned with the Commercial National Security Algorithm (CNSA) Suite from the Committee on National Security Systems to forther protect Wi-Fi networks with higher security requirements such as gover...

Back in my day, we called it The Corner .  Nowadays, the kids call it The Trap . (WARNING: Very NSFW) The average IT professional may not view Wi-Fi "Design" as being directly analogous to the inner city drug trade.  Yet, when Wi-Fi Professionals go through the process of choosing AP installation locations, they should know what even the most novice  B.G. drug dealer knows: that The Corner is also The Trap. When embarking on a Wi-Fi "Design", some things are obvious.  Coverage is needed everywhere.  The number of available APs must be appropriate for the number of expected Wi-Fi devices.  Physical objects (walls, doors, et al.) should be accounted for. A less obvious part of Wi-Fi "Design" is avoiding Hidden Node problems.  The Hidden Node problem occurs when two or more devices on the same channel A) cannot "hear" each other, and B) can interfere with each other. The reason why Hidden Node is a problem is that Wi-Fi devices rely o...