Clever SSID Naming

When we set up our networks in the UEWA class our students get to pick the name. We’ve had some pretty funny ones over the years. Here are some of the best. Tom Lawrence @Lawrencesystems.com contributed to this list:

IP4U

I believe Wi can Fi

EZHACK

No more Mr Wi Fi

Tell my Wi Fi love her

Wi Fi the Feeling

The Promise LAN

CIA Van

Collision Domain

PWD is admin-1234

 

 

 

WiFiMan Desktop app

When teaching the UBWA class, I have had students download the Device Discovery Tool from the Ubiquiti download page, but recently we’ve run into a problem with the tool.  In order to run it you have to have Java installed, but the Device Discovery tool doesn’t work with the latest version of Java, version 8 update 291.  In order to run the tool you need Java version 8 update 251, and it’s difficult to find Java 8.251.  if you want the old discovery tool You can download Java 8.251 64bit here https://www.filepuma.com/download/java_runtime_environment_64bit_8.0.2510.8-25279/ 

Then you can install the old Device Discovery tool from here: https://www.ui.com/download/utilities/default/default/device-discovery-tool-java-all-platforms

However, you may want to try the new WiFiMan desktop app instead. It runs discovery just like the Java tool but it runs as an executable file. It can run on Windows, Linux, and MAC. The problem I found is that it’s hard to find the download location for it. The app isn’t fully functional yet so the version that you download says it’s version 0.2.2.

You can download the desktop app here:

https://community.ui.com/releases/WiFiman-Desktop-0-2-2/74d8bc1d-6735-444b-a7fc-0ea2584ccb89 

As for now, we are kind of stuck in-between tools. People are having trouble with the Discovery of devices through WiFiMan.  The Java version works well, but only on the older version of java.

My advice is to try them both and see what works for you. For now, I’m going to use the old Java based tool and hope that the WiFIMan Desktop app is released in a functional version soon.

Does Wi-Fi cause radiation sickness?

Back in the 1970’s when I joined the military, I was in a Scout platoon and I was trained as a Ground Surveillance Radarman, MOS 17K.  The device that we used created a radio wave in the J Band (16GHz).  We used headphones to listen for changes in the 10KM area in front of us. We learned to be able to detect tanks, jeeps, and if we were really good, we could detect people moving through the area. The nomenclature of the Radar was AN/PPS5. It had a 1 degree bandwidth and a 50dBm transponder.

The old-timers in the platoon would tell the newbies, “If you stand in front of the radar for too long it will make you sterile.”

Apparently that wasn’t true because those guys spawned a new generation of tin-foil hat wearing crazies that claim Wi-Fi signals can harm you if you stand in front of an Access Point, or hold your smart-phone too close to your head.

Wi-Fi is based on creating radio waves in the 2.4 and 5GHz bandwidth spectrums. They are specific frequencies, created by an intentional radiator that emit from a directional antenna. The radio waves are part of the electro-magnetic spectrum, just like light waves, x-rays, and gamma-rays. As part of the electromagnetic spectrum, Wi-Fi radio waves travel at the same speed as other radio waves, so if anyone ever complains that the Wi-Fi is slow you can tell them that it’s travelling at the speed of light (300,000,000 m/s)!

 

The radio waves in 2.4 and 5 GHz measure approximately 5.5” and 2.25” respectively, so they are not small enough to penetrate cells in our body and thus pass through. Our bodies do absorb some of the energy that is emitted from an intentional radiator as it passes through us so the question is, how much power is emitted from a wireless access point?

Wi-Fi is a very low power technology. The amount of power generated has to match the power domain of the devices that the access point will support, otherwise our smartphones and computers would be able to receive the signal but the access points would not be able to detect the incoming signals due to a power mismatch.  That signal strength has been determined to be around 20dBm. At this power level smartphones can create the power needed without needing to increase the form factor of the device.

You might ask, how much power is 20dBm? DBm stands for decibels per milliwatt.  It’s an algorithmic representation of power based on the watt measurement system. 20dBm equates to 100mW which is one tenth of one watt. So the total amount of power that is emitted from an Access Point, and measured directly on the face of the AP, is one-tenth of one watt.

As the Wi-Fi radio wave travels through the air it loses power so that after the wave travels one meter the strength has dropped by 40-47 Db, so that at one meter out the signal strength will be less that one milliwatt. Not enough power to do much more than elevate a radio-wave above the noise of other radio waves and definitely not enough power to affect our cellular tissue.

The AN/PPS-5 had an Intentional Radiator of 50 watts, so it was considerably stronger than a Wi-Fi Access Point. It created waves in the J band, which is in the 16 GHz range. That converts to about .75 inches wide, still, hundreds of times larger than a cell.  So even though I spent a lot of time in front of our Ground Surveillance Radar system, I was still able to produce a normal family.

 

Blessings from the Webers!

Training with then Cloud Gen2+

This weekend I’m headed to Orlando to teach a Sat/Sun class on UniFI. I’ve started using the UCK-Gen2+ and creating “sites” for each user. This is turning out much better than having students create their own controller on their PC. It still gives students the capability to configure the controller. Now each student gets two ports on a switch and they connect their computer and an AP into a VLAN that’s created prior to class. That way they can control the AP and make config changes.

This week I’m bringing along a SHD that we can look at because it has AirView and AIrTool on it. Two very nice tools that I’d like students to see. We are still using the AC-Lite APs, which I like a lot.

I recently bought an LTE, but I haven’t installed it yet. Maybe we will get a chance in an upcoming class. I’d like to use it because WiFi in the hotels is almost always sketchy. Hopefully I can transition over soon and make it part of the class.