The USB-based Wi-Spy Mini is a 2.4 GHz RF receiver / detector. Since it "sees" more than just 802.11 networks, it can detect 2.4 GHz RF activity the Wi-Fi card on your laptop can't detect, but that could be causing interference to your Wi-Fi network.
For example, microwave ovens are known to cause Wi-Fi interference. In the screenshot below, notice the small blue lines within the straight lines. They represent detected RF within the frequency used by the detected SSIDs. This screen shot was taken with my laptop about 6 feet from a microwave oven that was turned off.
This next screen shot shows the the RF activity with the laptop in the same location with the microwave oven running. Clearly, there is a lot of interference now that can impact Wi-Fi performance. The take-away here is the Wi-Spy Mini included with the inSSIDer for Office product provides a level of information you don't get with the free versions.
inSSIDer Office calculates a value called Link Score for each SSID. This value is based on signal strength, the number of overlapping networks, RF activity and the number of SSIDs operating on that specific SSID. A perfect Link Score is 100. The lower the Link Score, the poorer your wireless experience may be at that specific location.
inSSIDer Home also calculates a Link Score, but it does not take into account RF congestion. So it can give potentially misleading results. In the top right of the screenshot, you can see the Link Score on SSID = MDC9 is 91.
The Analyze tab provides multiple "Observed Issues" per SSID. Up to 8 SSIDs can be analyzed simultaneously with inSSIDer for Office. The messages displayed per SSID include Low Signal Strength, Recommended Channel, Non-Standard Channel, Strong Co-Channel Network(s), Strong Overlapping Network(s), Overlapping Starred Networks, Weak Security, and Poor Channel Placement. Clicking on the message provided in the Analyze tab presents further output with recommendations on how to rectify the issue.
I was able to recreate the six of those messages, but couldn't recreate the messages for Weak Security or Poor Channel Placement. I was surprised I didn't get the Weak Security message, as inSSIDer correctly detected one of my Wi-Fi networks was set to Open security. In Table 1 below, I've listed the output for each message.
|Low Signal Strength||From this location, the signal strength of (SSID) is lower than recommended. This will cause slower-than optimum throughput rates as well as connectivity issues. Deploying an additional access point may give greater coverage if accessing (SSID) from the spot is desired.|
|Recommended Channel||Improve the Link Score by switching (SSID) to Channel x.|
|Non-Standard Channel||(SSID) is currently deployed on Channel x, which is a non-standard channel. For best speed and connectivity, please place your network on channels 1, 6 or 11.|
|Strong Co-Channel Networks||(SSID) shares channel x with one or more networks with especially strong RSSI (signal strength). Since wireless activity from (SSID) competes for available airtime with these strong-signal network(s), low throughput is likely to occur.|
|Strong Overlapping Networks||(SSID)'s channel is overlapped by networks with strong RSSI (signal strength).|
|Overlapping Starred Networks||(SSID1) and (SSID2) are overlapping each other. This condition will cause slow speeds on each network. Please use the standard non-overlapping channel scheme of 1-6-11.|
Table 1: "Observed Issue" messages
I found that inSSIDer for Office was easy to use, easy to install, and provided clear information. Having numerical information about each SSID at each location throughout the building I used for testing made it quite clear whether the Wi-Fi network in each location should be adjusted.
The key to optimizing wireless performance is maximizing signal strength and minimizing channel and RF interference in areas where the wireless network is most commonly used. inSSIDer for Office enables you to do just that by providing precise signal strength measurements, displaying the number of SSIDs on each channel, and graphically displaying RF activity.
With the free versions of inSSIDer, you can measure signal strength and determine which channels are in use. For $199, inSSIDer for Office provides more detail on a per channel basis, analysis and recommendations, as well as insight to RF activity.
You've heard the saying "use the right tool for the job." If I'm tasked with optimizing a wireless network for a business, I want all the details and recommendations I can get my hands on to take the guesswork out of where to install APs and what channels to use. In my mind, inSSIDer for Office is the right tool for that job!