Analyzing Network Coverage

Two methods were used to gauge the coverage of the wireless network once it was installed, the bandwidth-measuring website and the free Mac OS X wireless survey tool NetSpot.

NetSpot Survey

Two tests were done of the wireless coverage using NetSpot, one on the lower level of the school and one on the upper level. The same maps used for the initial site survey were loaded into NetSpot, a known measurement entered (staff room is 28 feet long), and then scans were done from multiple locations on each level to measure wireless signal strength from every classroom.

Once the walking survey was completed, NetSpot generates a "heat map" showing wireless signal strength over the covered area. The app shows all wireless signals from all networks (there were 33 other wireless networks detected in the neighbourhood by the app). Limiting the heat map to the "TeacherNet" access points, the results are:

Note that these heat maps show only the wireless signal strength, not network throughput. Note as well that on the upper level's heat map you can see the lack of coverage in the lower-left wing because of the issues with "daisy chaining" the OM2P access point in that location, which we hope to address.

The NetSpot survey files for the lower level and the upper level can be loaded into the application to see more details about the coverage. Bandwidth Tests

For more "real world" testing of connectivity, each classroom was visited with a MacBook Air connected to the TeacherNet network, and the bandwidth test was run while sitting at the educator's desk in each room (the likely location from which they would use the network). The result was a downstream and upstream number, in megabits per second, for each classroom, that looked like this:

The class-by-class results of this test were as follows:

The results are available as an Excel spreadsheet.

The diminished bandwidth measured in Room No. 1, the Kindergarten, was because that node is currently operating in wireless "mesh" mode, and, as a child of a first-generation hard-wired node, its bandwidth is half of the maximum.