THE BAD-FI

Sad-Fi. 🙁

AP on metal.

Below metal.  

Beside metal.  

Surrounded. By. Metal.  

The #1 type of BAD-FI that I see. People still don't get that radio waves need to be able to get to the client. 

 

STOP BLOCKING YOUR APs.  

From the unexpected attenuators file… via @scottm32768

So, here's a good example of why you should at least do a spot check to see if anything's changed in your environment. Like, I don't know, teachers mounting ROUND METAL THINGIES from the ceiling?!

Also, AP mounted DIRECTLY on metal. :-(

Ok, I'm calling it - mounting near, on, or around METAL is the #1 stupid thing on BAD-FI.

    Ok, ok, you win!!! Install APs on metal for all I care!!! via @gugamastroianni

    • APs designed for HORIZONTAL mounting installed VERTICALLY. This is why it's important to understand antenna patterns.
    • APs mounted DIRECTLY on what looks like walls with METAL on them. People, WiFi and METAL DON'T MIX.

    Well, at least they got the antennas right. (sigh) via @EmperorWiFi

    "Just when I thought I was out... THEY PULL ME BACK IN!!!!"
     
    - Michael Corleone

    At least the antennas are correctly positioned. But, AP mounted directly on concrete, METAL cable tray directly in from of AP, antennas right next to concrete overhang. Geez, you'd think someone at MIT could figure this out. 

    Another Reminder that Metal & WiFi Don't Mix

    Sadly, this is very common. In the following replies to this Tweet, Todd correctly recommends that his customer suspend the AP below all the metal obstructions.

    Typically, when we do that we use a piece of all-thread, cut to size, attached to a 4-gang box to mount the AP from. Here's a good example from Jennifer Huber's blog.

    There are a few issues here:

    1. The AP being so close to metal (in this case the very beam it's attached to) means that the immediate reflections from the metal start to distort the signal as soon as it emanates from the AP.
    2. The metal below the AP are blocking, AND reflecting that signal.

    This all adds up to a poor user experience on the ground. Where the signal is degraded, blocked, and attenuated.

    For an idea of how metal affects RF signal I refer you to this excerpt from the CWDP (Certified Wireless Design Professional) Study Guide:

     

    “Examine an antenna, and you will find that it is made of metal parts and dielectrics. The metal parts of the antenna do not even have to be touching each other. It should be clear that bringing metal or dielectrics close to an antenna can have a dramatic effect on performance.”
     
    Excerpt From: Shawn M. Jackman, Matt Swartz, Marcus Burton & Thomas W. Head. “CWDP Certified Wireless Design Professional Official Study Guide.” iBooks. 

    (Click the link to read the rest of the chapter and view the excellent graphic)

    So, be aware of where your APs are placed, and what surrounds them. Give the RF some time to propagate before it comes back and slaps that AP upside the head.

    :-)

    tumblr_ntlu0vLMCe1qbd6x4o1_1280.jpg

    @HeyEddie quality airport AP mounting pic.twitter.com/66rR5diudU

    — Shaun Neal (@sv_neal)

    August 7, 2015

    —

    Yes, Wi-Fi is EXACTLY like Magic Pixie Dust! You sprinkle a ‘lil over there, and a ‘lil over here, and Voila! Inter-webs at your service!

    It’s a nice fairy-tale, but in reality Wi-Fi is “stuff”. Invisible, high-frequency stuff, mind you, but “stuff” none-the-less. That’s means it’s affected by other stuff like, oh, I don’t know GIANT, METAL, KIOSKS, maybe?

    Metal AFFECTS radio frequencies. Water AFFECTS radio frequencies. Heck, PEOPLE affect wireless frequencies! 

    Take care where you place your APs, and understand how the antennas propagate the RF signal. Even a base understanding of this would have kept this wonderful, little example of “Wireless Design” from happening.

    Yeah, we could complain about TP-Link this, and Ubiquiti that, but properly designed and INSTALLED Wi-Fi solutions work pretty well in most situations.

    AND GET YOURSELF ONE OF THESE. You’ll thank me. →

    Well, AFTER you read it you’ll thank me.
    No need to thank me now.
    But, you will.
    Go ahead - I’ll wait.

    “One of the examples of the high quality installation work encountered when auditing a public wifi network at a large student accommodation facility recently.”SUBMITTED BY: @TheEvertBopp—RF device in metal box.How. Does. This. Keep. Happening?

    “One of the examples of the high quality installation work encountered when auditing a public wifi network at a large student accommodation facility recently.”

    SUBMITTED BY: @TheEvertBopp

    —

    RF device in metal box.

    How. Does. This. Keep. Happening?