Using a GPS to perform a Wi-Fi survey

It is important to perform a wi-fi survey so that you can determine not only the perfect place to locate your access point or bridge but to gain an understanding of the channel co-existence challenge you may face.  With wireless access points in surrounding neighborhoods and businesses, you will need to  perform a survey by walking around and mapping out the BSAs (Basic Service Area) of wireless that surrounds you and your organization.

Below is an example of our school’s perimeter.  Matt, Chris and James, students in the Computer Information Technology, class performed a survey using a Microsoft GPS and Vistumbler.  This survey revealed access points and their channels of current wireless at our institution and  includes APs in surrounding businesses and neighborhoods.  These were mapped using Google Earth after exporting their KML file from Vistumbler.

This type of survey allows IT professionals to analyze data exported to ensure the correct channels can be used at their organization.

Miller Goodroe Felts

After exporting the wireless information, you can analyze each access point or wireless device by clicking on it.  Below is an example of the information exported into Google Earth.   Each device shows SSID, Network Type, Mac Address, Channel, Security, Encryption Type, Data Rates, Latitude, Longitude and Manufacturer information.   Analyst using this information can also determine the best placement of wireless devices along with channel information.

ESSID Expanded

Channel co-existence is when access points share channels that are very close to one another.

802.11 wireless on 2.4 Ghz has three non-overlapping channels.  These channels are 1, 6 and 11.  The closer channels are, the more likely interference will take place.  With the amount of wi-fi in use today, IT professionals have to chose between 2.4 Ghz and 5 Ghz and and try to select channels that are not in use if possible.   Professional access points and bridges can also adjust power as necessary.   A dense population can make this very challenging.

If you look at the students’ survey by zooming out to see how many access points can be seen, this is what you are looking at!  Now you can see why site surveys are important at your organization.

Exploded

In addition to this survey, a secondary survey using a spectrum analyzer is very important to search for interference from other sources.  (See our review of the Airview Spectrum Analyzer)

analyzer-software

Channel information (Chart from Wikipedia)

NonOverlappingChannels2.4GHzWLAN-en.svg

Here’s another look at a wireless survey showing vertical lines and signal strength.  (James M. KML survey)

Another view James Miller KML

Achieving Excellence in the New School Year – Computer Information Technology at TCAT-Shelbyville

Our Information Technology Career Cluster winner, the Tennessee College of Applied Technology (TCAT) Computer Information Technology (CIT) program has been working hard over the summer to expand its outreach efforts, stretch its curriculum across Career Clusters and reach more students…more

Configuring WDS to extend your wireless network

Want to extend your network and make it more reliable and robust?   

Here’s what you will need -

  • Two routers with the same firmware
    • Preferably Tomato or DD-WRT

Login to the first router.  

In this example, the static number 192.168.1.1 is the Main router.

  • Enable the WAN to match your ISP  
  • Enable DHCP
  • Enable Access Point + WDS  (Picture two below)
    • You must have the same wireless configuration on both routers
      • Enter the MAC address of router two under WDS Link with.

Router 1 no 1

Router 1 no 2

Login to the second router

  • Disable the WAN
  • Disable DHCP
  • Assign the router a static IP address (Below we have given the router .250)
  • Enter Router One’s IP Address for the Gateway
  • Enter a DNS of your choice
  • Make the wireless configuration the same as the first router.  Under WDS, change the drop down to automatic.

Router 2 no 1

Router 2 no 2

With the same settings, you can now extend your network several hundred feet under the right conditions.  Because the SSIDs are the same, once you join one of the routers with a smartphone or laptop, it will seamlessly change to the stronger signal.

With Tomato, you can chain together approximately 12 devices.

Links-

Tomato RAF

Shibby’s Tomato

DD-WRT

Note; The IP addresses and MAC addresses are in a lab environment.

How does it look on a network map?  The two routers are actually connected together.  The switch is the four ports on the back of the router closest to the internet.

Map

HP Pavilion 11 x360 Review

I usually don’t review hardware products but I felt a need to review HP’s Pavilion 11t-n000 x360.   

My father-in-law wanted a Microsoft Surface but still wanted a keyboard and the functionality of a laptop.   He also wanted to avoid the expense of a Microsoft Surface and wanted something with a small profile, light weight, lots of storage and plenty of ram for traveling.  He found the HP Pavilion 11 x360 that has the following features:

  • Quad core Pentium 2.17 Ghz
  • Windows 8.1 64bit
  • 4 GB DDR3 
  • 500 GB HD 
  • Beats Audio
  • less than 1″ profile
  • Screen 11.6″ (Touchscreen)
  • Gyros built in
  • 1 -USB 3.0
  • 2 -USB 2.0
  • Wireless 802.11
    • Miracast compatible 
  • Ethernet Port
  • 5 hour battery life (45 watt AC adapter)
  • SD Mediacard Reader
  • 12.12 x 8.46 x 0.86 in 
  • 3.08 lbs
  • HDMI
  • TruVision Webcam
  • 1 year warranty

I expected the laptop (netbook?) to be slow.  I was surprised at how responsive it was with 4GB of RAM.  It is by no means a powerful gaming computer but is a match for home, business or school users.   The pc is upgradeable to 8GB and a hybrid hard drive which would make a difference in performance.  Is this necessary for the typical user?  Probably not.

Once you setup a Microsoft account, Windows 8.1 has the Microsoft store (which now has over 400,000 apps ) and OneDrive to backup and sync pictures, files and more. 

With the HP Pavilion 11, you can fold the keyboard to have a tablet or you can flip the keyboard down and use the pc in ‘tent’ mode so it supports the tablet functionality.   Folding the keyboard under the touchscreen gives you a tablet.   The touchscreen is very responsive to the slightest touch.   

20140817_135729      20140817_135748

At $399,  I don’t know why you would buy a laptop or a tablet.   

More Information

 

Free College? The Tennessee Promise

TNPromise

Beginning with the Class of 2015, the Tennessee Promise will provide Tennessee high school graduates the opportunity to attend a community or technical college free of tuition and fees.

More information about the Tennessee Promise  (PDF download)

Going to take a certification that involves binary?

Going to take a certification that involves binary?

Here’s a quick tutorial~

Let’s say you are given an IP address of 192.168.1.135 in an answer.

What is this number in binary?

Here’s what you do.

Take a simple key to convert the numbers in the octets into binary.
The key is this:

128   64   32   16   8   4   2  1

Now let’s take the first octet of 192 and let’s see how many times the numbers above (the key) go into the given octet.

How many times does 128 go into 192?     192 – 128        1 time
This will leave us 64.
Next, how many times will 64 (your remaining number) go into the next number in the key(64)?

64 -64       1 time

Now the remaining number is 0.   So if you subtract 32 from 0 the number will be 0.  16 from 0 is 0, 8 from 0 is 0, 4 from 0 is 0, 2 from 0 is 0 and finally 1 from 0 is 0.

Look at your answers. 11000000 -This will represent 192.

Now let’s do the 168 octet.

128 goes into 168 – 1 time.   The remaining number is 40.   64 goes into 40 – 0 times.    32 goes into 40 – 1 time.  This gives you a remainder of 8.   16 (the next number in the key) goes into 8 how many times? 0 . 8 goes into 8 – 1 time.  The remainder is now 0.    4 goes into 0 – 0 times.   2 goes into 0 – 0 times.  1 goes into 0 – 0 times.   Look at your answers (bold).

168 will be 1010100

Of course the next number (third octect) which is 1 will be 00000001.

If you use the above key for 132, along with the subtraction method, 132 will be 10000100.

Your final answer is 11000000.1010100.00000001.10000100

 

Try a these yourself using the subtraction method above -

192.168.1.32
192.168.1.111

 

Flip over and see the answers

11110110˙10000000˙00010101˙00000011
01100100˙10000000˙00010101˙00000011
:ɹǝʍsuɐ

How to tie your cloud storage services together

How can you tie your cloud storage services together?   It’s actually easy if you use MultCloud.   MultCloud ties together all of the most popular cloud storage services so you can upload files to multiple sites through a single sign-on.

Completely FREE app for home and commercial use.
Single login for multiple cloud accounts.
Add unlimited accounts such as Dropbox, Box, OneDrive, etc

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Add Cloud

Signing up is easy and free.   Once you sign in, you can connect your cloud services and use the power of MultCloud to Upload or Download files from a central dashboard.

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