Wi-Fi stumblers and analyzers are a must-have when troubleshooting Wi-Fi interference and performance issues, or when simply checking channel usage on the wireless bands. They\u2019re also needed for Wi-Fi site surveys during the network design and deployment phases, as well as for security audits to look for rogue or misconfigured access points.\nEach tool gives you the basic wireless details of nearby access points: SSIDs, signal strength, channels, Media Access Control addresses, and security status. Most can even reveal \u201chidden\u201d or non-broadcasted SSIDs. Some offer additional functionality, such as details of nearby wireless clients, raw 802.11 packet capturing, frame statistics, performance testing, and map-based surveying.\n+ ALSO ON NETWORK WORLD: 7 free Wi-Fi stumbling and surveying tools +\nHere we review five low-cost Wi-Fi stumblers and analyzers: Acrylic WiFi Professional, insider 4, NetSurveyor, Wi-Fi Scanner and WirelessMon. It should be noted that, with the exception of Acrylic WiFi Pro, these entry-level tools don\u2019t show you the noise or signal-to-noise ratio (SNR) values like higher-priced enterprise solutions do. Here are a few quick takeaways:\n-- If you\u2019re looking for something really simple, consider the least expensive stumbler here: inSSIDer 4. It\u2019s user-friendly, gives you channel recommendations and helps identify interfering access points. However, it doesn\u2019t offer any saving or exporting. If you\u2019re looking for something more advanced, particularly with the ability to detect non-802.11 interference, take a look at the inSSIDer Office edition. It comes with the Wi-Spy adapter to take full RF spectrum measures with inSSIDer in the Wi-Fi bands.\n-- Acrylic WiFi Professional is a great option for more advanced wireless technicians since it can show the raw 802.11 frames, aid in penetration testing of Wi-Fi security, and even show the signal-to-noise ratio (SNR) values of the access points. However, entry-level techs might be turned off by the lack of help and documentation.\n-- If you want to check the Wi-Fi performance or prefer a stumbler that can generate reports, consider NetSurveyor Professional. However, since it doesn\u2019t provide full channel or security details and doesn\u2019t offer graphs for 5GHz, it\u2019s not the best tool for general surveying.\n-- If you\u2019re looking for an inexpensive map-based survey tool, or a tool that can help detect non-802.11 interference, take a look at WirelessMon. However, keep in mind that detecting non-802.11 signals or interference does require the Wi-Spy RF spectrum adapter, just like with the inSSIDer Office tool.\n-- And if you\u2019re looking for a simple stumbler that also gives you details on frames counts, consider Wi-Fi Scanner from LizardSystems.\nHere are the individual reviews:\n\nAcrylic WiFi Professional\nTarlogic Security offers Acrylic WiFi Professional, a Wi-Fi stumbler and analyzer that supports packet capturing and password cracking, regularly priced at $26.99. You can download a free trial of the Professional edition but it\u2019s limited to four days use. There\u2019s also a free edition with less functionality and a heatmap Wi-Fi surveying tool as well.\nWhen you open Acrylic WiFi Professional, you see the list of detected SSIDs. On top of the application you can toggle wireless capturing on and off, and toggle between the normal, monitor, and AirPcap modes. The monitor mode, also commonly called promiscuous mode, allows you to capture all wireless traffic; not just the traffic of your wireless connections.\nIn addition to the typical wireless information shown for the detected SSIDs, you see the Wi-Fi Protected Security (WPS) details for those that support it. It also can reveal hidden SSIDs, recognize larger channel-widths, and distinguish between PSK and enterprise security modes. You can give SSIDs aliases by adding them to the saved inventory list, useful to help you distinguish between real and rogue access points. We didn\u2019t however, find any real filtering capabilities; just the ability to hide SSIDs and stations after a certain amount of time from when they were last seen.\nUnlike most stumblers, Acrylic WiFi Professional can provide real SNR values when using an AirPcap device. The SNR values are highly useful when troubleshooting interference and performance issues and is usually only seen in high-priced enterprise tools.\n\nOn the bottom portion of the SSID list, you can tab between many graphs, lists, and details. One graph shows each SSID\u2019s signal strength. Another shows network quality ratings and along with detailed descriptions, suggestions, and solutions.\nUnder the list of SSIDs, you also have a tab to see a list of further network details of each SSID, a list of network requests from clients, location settings if using GPS capturing, and a tab to use when testing password security with their built-in brute-force cracker.\nFrom the main menu on the left of the application, you can tab between other screens. The Stations screen shows a list of all detected Wi-Fi devices and their details. The Packets screen shows the log of raw 802.11 packets and allows you to view the frame contents and details, which all can be saved and exported into a PCAP file. The Scripting screen is where you can generate scripts for use with the built-in brute-force password cracker.\nAcrylic provides a few ways of saving and exporting collected data. You can save a PCAP file containing the raw 802.11 packets and also save the list of SSID details and graphs via export using the clipboard, HTML file, or images.\nThey provide some help and documentation on using the application, however it\u2019s not organized that well and the full manual they provide online is only available in Spanish.\ninSSIDer 4 \nMetaGeek provides a handful of Wi-Fi surveying, troubleshooting, and optimization tools. The inSSIDer 4 Wi-Fi stumbler, available for both Windows and Mac OS X, is priced at $19.99. No free trial is offered, but there\u2019s a 30-day money back guarantee.\nThe inSSIDer 4 GUI is very simple and straightforward. On the top portion of the application you find the access point list, which can be filtered based upon SSID, MAC address, channel, or signal. However, you won\u2019t find the ability to name the SSIDs or access points with aliases nor can you save or export the SSID list or details. Depending upon your wireless adapter and driver, it\u2019s possible to detect and reveal hidden SSIDs, but it\u2019s not officially supported by inSSIDer. However, larger channel-widths are recognized and security is distinguished between the PSK and enterprise modes.\nOn the bottom portion of the main screen, you see graphs showing channel usage and signal strength for both bands. Any SSIDs with larger channel-widths are depicted in the graph as well.\n\nYou can toggle between grouping the access point entries by radio in physical view or grouping by SSID in logical view, which we found convenient. Physical grouping means each line on the list represents a single physical radio on an access point, which could be hosting more than one SSID, and is usually good when you are working with a single access point. Logical grouping means each line on the list represents a SSID, which could be broadcasted on more than one radio or access point, and designed for when working with multiple access points.\nAmong the usual\u00a0access point details, you see the minimum and maximum supported data rates, which isn\u2019t always shown by Wi-Fi stumblers. However, you\u2019ll only find the signal strength given in negative dBm values; no additional percentage or signal bar indicator in the list of details.\nOn the access point list you can click on the column labels to sort the list using the values from that particular column. When you select a SSID or access point entry you see a signal strength graph and other details depends upon what view you\u2019re in.\nIn physical view, clicking an entry shows you a list of the virtual SSIDs on that radio. To help you identify interfering access points, it also conveniently shows you the recommended channel for that particular radio and lists the strongest\u00a0access point that\u2019s on the same or an overlapping channel, if any.\nIn logical view, clicking an entry shows you a list of all the different access points that are broadcasting that particular SSID.\nThough inSSIDer is a very simple program, it offers a good online user guide that explains the details and functionality while also providing general Wi-Fi troubleshooting tips.\nNetSurveyor Professional\nNetSurveyor Professional is just one wireless tool of many provided by Nuts About Networks. Priced at $34, it provides the Wi-Fi scanning functionality from their free edition, while adding performance testing features. They offer a fully functional trial, but you\u2019re limited to opening the application 10 times.\nAfter opening NetSurveyor Professional, you\u2019re met with the Connection Analysis screen. In the upper-right corner is the list of up to five wireless adapters currently installed and stats on their connections, including RSSI in negative dBm values and throughput percentages relative to the maximum real-world data rate. The maximum rate is configurable and by default set to 23.8Mbps. In the upper-left corner is a heatmap or waterfall chart, also showing the throughput percentages of each adapter.\nOn the bottom portion of the Connection Analysis screen, you can toggle between four charts, or show all at once. The time course view shows a line graph of the throughput values over time for each adapter and the spectrogram view gives you different visual of the same data. There\u2019s also a line graph showing connection breaks and a bar graph showing the average throughput and standard deviations of each connection.\n\nOn the Network Discovery screen is where you find typical Wi-Fi scanner or stumbler details. Though we found it could reveal hidden SSIDs, it doesn\u2019t recognize larger channel-widths (even overlapping channels in 2.4GHz) nor distinguish between PSK and Enterprise security. Additionally, you won\u2019t find any filtering functionality for the SSID list, besides hiding SSIDs from appearing on the graphs.\nOn the bottom portion of the Network Discovery screen, you can toggle between several graphs showing the signal levels and channel usage in different visual representations. However, none of the graphs show signal or channel usage for any access points in the 5GHz band, and even for 2.4GHz no channel overlapping is shown.\nThere are two ways in which you can save or log the results. First, you can create a report. This takes a snapshot of most of the current data and graphs and puts it into a PDF. The logging functionality allows you to record the capture so you can then replay it to see the synchronized connection stats and throughput graphs.\nThough the GUI and operation are straightforward, they still offer thorough documentation via an online help link.\nWi-Fi Scanner\nWi-Fi Scanner is from LizardSystems, which also has several other network-related utilities. It serves as a basic Wi-Fi stumbler and gives detailed connection stats, which can also be used for troubleshooting. After the fully functional 30-day evaluation period, you can register for the free Basic edition with the connection statistic functionality disabled. The full Standard edition costs $79.95, which is relatively high when compared with similar tools.\nWhen you open the application, you\u2019re met with an attractive and user-friendly GUI. You can see the list of SSIDs on the top portion and to the left of that you can easily filter the list based upon signal quality, network type, security type, and wireless band. Though it distinguishes between PSK and Enterprise security and recognizes larger channel-widths, it doesn\u2019t fully support 802.11ac.\nOn the bottom portion of the main screen, you can flip through a few graphs: combined signal strength of all SSIDs and then a graph showing channel usage and signal strength for each wireless bands.\n\n\u00a0\n\u00a0\ncutline: Wi-Fi Scanner opens to the SSID list and graphs, and allows for easy filtering on the main screen.\nOn the Wireless Information screen, you can see the details of the current wireless connection, which you can toggle between different wireless adapters. Line graphs and counters are also shown for various MAC and PHY layer frame types, including total transmitted, received, failed, and different encryption frames.\nOn the Wireless Information screen, you can click the Profiles tab on the right to view the list of wireless network profiles saved by Windows. This isn\u2019t useful unless you\u2019re running Windows 8 and later.\nThough it\u2019s not very apparent with Wi-Fi Scanner, you can export all data including the graph images. However, it\u2019s a pretty crude way: you right-click on the data, copy to clipboard, and then paste into an appropriate program, such as a text editor, spreadsheet, or image editor.\nOther than the exporting, everything else is self-explanatory. However, it would be nice if they offered some real documentation. Clicking the Help shortcut takes you to their support page, but the only information we could find is some FAQ.\nWirelessMon\nWirelessMon is a Wi-Fi stumbler that also offers basic integrated map-based surveying and RF spectrum scanning with Wi-Spy. It is provided in a few different editions by PassMark, which offers other general computer testing tools and is the host of many popular hardware benchmark databases. They offer a free limited edition for up to 30 days, Pro edition ($49) with all functionality, and then a Standard edition ($24) without the GPS or mapping capabilities.\nWhen you open WirelessMon, you\u2019re greeted with an old style GUI. On the top portion of the main screen, you see the details of your current wireless connection along with a simple bar chart showing the channel usage and signal level of all SSIDs. For channel usage you can toggle between 2.4GHz, 5GHz, and RF spectrum levels if using Wi-Spy.\n\nOn the bottom portion of the main screen, you find the list of the detected SSIDs and their details. Most of the usual details are shown, including any hidden SSIDs that have been revealed. However, 802.11ac and larger channel-widths aren\u2019t fully recognized.\nOn the left of the application, you can tab between other screens. On the Statistics screen you see counters for many different 802.11 frame types, including total transmitted and received, failed, and retries. On the Graphs screen, you can view simple line graphs for signal strength and data rates.\nOn the IP Connection screen, you find the details of the currently selected adapter and the IP address details of its present connection.\nOn the Map screen, you can upload a floor plan or map to perform map-based surveying. Once you collect samples by clicking your location on the map or using GPS, it will create a heatmap of the signal levels for your desired access point(s) or channel. This is a very simplified version of what\u2019s offered in enterprise-level surveying products, such as AirMagnet, Ekahau, and TamoGraph.\nThe application provides saving, logging, and exporting features. The logging function saves summary information in a text file and then access point and connection details in text or map-based formats. There\u2019s a simple filtering setting that allows you to specify the particular SSIDs you to want to be saved by the logging. The application also allows you to save your project, which keeps the list of SSIDs and any samples taken for the signal strength map. You can also independently export the SSID list and heatmap.\nWe found the help and documentation to be thorough and useful. When you click the help button, it conveniently opens to the related page from the online documentation.\nEric Geier is a freelance tech writer\u2014keep up with his writings on Facebook or Twitter. He\u2019s also the founder of NoWiresSecurity providing a cloud-based Wi-Fi security service, and On Spot Techs providing RF site surveying and other IT services.