Question

One of my favorite tools is called inSSIDer by MetaGeek. inSSIDer is a wireless network scanner. It was meant to replace NetStumbler, which was a Microsoft Windows Wi‐Fi scanner. There is a free version with limited features called inSSIDer Lite, and you can download it from https://www.metageek.com/products/inssider/free/ .

inSSIDer intercepts information from wireless devices and will report all of the wireless networks that are nearby. It will report details such as the SSID of the WAP and what channels the device is using, as well as signal strength, the physical type of the WAP, if it's secured, and the minimum/maximum data rate. You also get a graph of the WAPs divided up by channels 2.4 and 5 GHz. In Figure 6.2 , you see that inSSIDer Lite captures the SSID of the broadcasting router, channel, signal, 802.11 type, and kind of security that is being used as well as minimum and maximum data rates.

Figure 6.2 : inSSIDer capture of Wi‐Fi

If you know what is happening around you, you can use this data to fix problems you might be having or improve your network performance. Most people will use inSSIDer to pick the best channel that no one else is using for the best reception and no interference. You can check to see whether your network is secure and what other networks have been discovered.

If there is a lot of traffic on wireless devices around you, you will see this displayed in the visualizations of what channel each access point is on. They can overlap and basically compete for airspace. Using inSSIDer, you can make sure your router is using the best channel. Looking at Figure 6.2 , notice that there is a router in the 5 GHz channel all the way over to the right that is not sharing airspace with anyone. Yes, that's me.

One issue everyone experiences from time to time are dead spots. They are one of the most common pain points of Wi‐Fi technology. Depending on which version of inSSIDer you use, there is an option to change from Physical to Logical mode. If you change to Physical mode, you can walk around your work or home environment to evaluate whether your router is in the correct spot. If signal strength dips below ‐70 dBm, you have a weak area. If it falls below ‐80 dBm, you have a dead spot.