Reference no: EM133695106

Choose a location and use a Wi-Fi scanning tool to determine the signal strength of Wi-Fi networks within a physical space, visualize your measurements by creating a "heatmap"-style plot, and analyze the results. Site surveys are an essential part of wireless networks administration and can help pinpoint signal-strength issues that have the potential to become security issues.

1. Installing a Wi-Fi scanning tool On either a smartphone or laptop, install a Wi-Fi scanning tool that updates responsively and shows signal strength of multiple networks in units of dBm (a negative number between -120 and -30). A recommended tool for Windows is NirSoft's "WifiInfoView", available at https://www.nirsoft.net/utils/wifi_information_view.html

2. Selecting measuring, and diagramming your space Select an area for your scan that you have access to and are allowed to scan. If it is at a workplace, be sure to get permission from your site administrators. The total size of the area should be at least 50 square meters (500 square feet). The area should all be on approximately the same level (not multiple floors.) The area does not need to be rectangular, and it can consist of multiple rooms and can be indoor, outdoor, or a combination of both, as long as there are measurable Wi-Fi signals for at least three networks. Measure the full dimensions of the space and draw a basic floorplan diagram, indicating walls and inside/outside areas. If you are aware of the location of any wireless access points, you may also mark those on your diagram. Then, mark a grid of points that are two meters apart for measurement. Your diagram must have at least 30 measurement points.

3. Initial scan and network choice Start your Wi-Fi scanning tool and walk around the space you have selected in an informal scan. Take note of the signal quality of various networks, and choose three networks to include in your formal scan. You do not need to choose the three strongest networks; you may wish to include weaker networks or networks with a more highly variable signal, in order to make your heatmap more interesting. For each network chosen, record the SSID (name) and whether the network is 2.4GHz or 5GHz. Page 2 of 3

4. The formal scan and data recording Start the scanning software, take your scanning device (laptop or phone) to each point you have marked out, and hold it up 30 seconds. Keep your device at the same height and oriented in the same direction at each spot. Write down the signal strength in dBm of your three chosen networks three times, at 0 seconds, after 15 seconds, and after 30 seconds. You will average the three readings for each network to get a more accurate number. If possible, do the entire survey in a single span of time, so that time of day, weather, usage, etc. will have as little impact as possible on your measurements.

5. Creating the heatmap Once you have finished your scan, average the three values for each network at each point. Also, choose a fake name for each of your three networks to anonymize your results. You can simply use "network 1", "network 2", and "network 3", or you may be slightly more descriptive, such as "mine", "neighbor 1", and "neighbor 2." Just make sure to choose names that do not reveal any location or personally identifying information. Use the provided "tkheatmap" program to create an RGB visualization of the signals. Make new heatmap of size big enough to fit all your data points in, then click each square corresponding to a measurement location and use the sliders or type in the signal strength for each of your three networks. You can leave any squares blank that don't correspond to measured places in your diagram. The signal strength of your "network 1" channel will be represented by the red channel, "network 2" by green, and "network 3" by blue. The brighter/lighter the colors, the stronger the signal, and the blending of colors indicates the degree of overlap. When interpreting your heatmap, keep in mind that RGB colors blend in this way: Red + Green = Yellow; Red + Blue = Magenta; Green + Blue = Cyan And the blending of all 3 colors produces white. Take a screenshot of your heatmap to paste in the report you will submit, described below. Use an image editing or paint program to draw any walls or boundary lines on the screenshot image.

6. Analysis written report to present the conclusions of your site survey. The report should have at least the following elements: - A description of the area you selected to survey: what type of environment it is, size, building materials, indoor or outdoor, residential, commercial, industrial, etc. - Include your hand-drawn or computer-drawn picture of the area, with the measurement points. - Describe the type of device (laptop, phone) you used to take the measurements and what Wi-Fi analyzer software you used. - Paste in the screenshot of your finished heatmap, with boundary lines drawn in. Page 3 of 3 - Also, include the complete table of all your measurements. You may wish to use a spreadsheet program for this and copy the table over. - Thoroughly analyze your readings and heatmap. Questions you may wish to address include: Which point has the strongest signal for each network? The weakest? What are the points of greatest overlap of signals? Do you see any evidence of interference or weakening due to overlap? Do the frequencies or channels used seem to affect this? If you have any experience with connecting to any of your chosen networks, you may also relate those experiences to the measurements you have made. The report must be written in complete sentences in paragraph style, with minimal or zero usage of bullet points. You may also use section headings to further structure your report. Put your name, the lab title, and the date at the top of your report and submit it on Blackboard.