NetSpot's Discover Mode, which we are discussing in this howto is a really powerful and completely free tool that easily leaves even paid WiFi scanners behind.
The purpose of a WiFi scanner is to discover all nearby WiFi networks and collect as much information about them as possible. WiFi scanners can be divided into two categories:
Since NetSpot is a software scanner, we’ll be using the term WiFi scanner to describe software scanners.
With a capable WiFi scanner, you can learn a lot about surrounding WiFi networks, their performance, and coverage. Here’s a brief overview of some of the most important information that you can obtain with the help of a free WiFi scanner app like NetSpot:
To discover what else can a WiFi scanner tell you about a wireless network, go to the end of this article, were we talk in more detail about information provided by NetSpot.
Before you use a WiFi scanner there are a few things that you should consider to obtain the most accurate results possible.
Launch NetSpot. By default, the program opens in Discover Mode, that's exactly what you need for a quick snapshot of the nearby WiFi networks.
If you are in the Survey mode after your last launch, just switch back using the control on the main toolbar.Step 2
You don't need to run a WiFi survey to get a quick overview of the surrounding wireless range. Wait a second or two and the detailed information about existing Wi-Fi networks around you will start appearing in NetSpot.
In previous versions of NetSpot you were supposed to run a tiny "fake" wireless survey on a blank map to scan for wireless networks. Since NetSpot 2.0, this is no longer required as we introduced full-featured Discover Mode. So you get the info about all the networks that are not hidden in a separate list. The list is updated every 5-10-30 seconds. If a network disappears, you can still see it in the list for some time, and find out how long ago it was gone in the Last Seen column.
To pause scanning for Wi-Fi networks, just click the Pause button on the lower toolbar. Scanning will stop until you restart it. If you see too many networks on the list, you can filter them by SSID (name) or BSSID (MAC-address).
NetSpot's Discover Mode provides detailed info on each wireless network, the list of visible parameters is configurable if you secondary-click the table's header. Usually you would be interested in the network's name, BSSID, vendor, mode, network security, wireless channel, signal level, Signal-to-Noise Ratio and more.
You can visualize and export historical values sorted by time for the networks discovered. To see historical data visualized in a live graph, click Details on the lower toolbar. To export this data into CSV, click Export on the main toolbar.
That's all there is to it! You now have completed your Wi-Fi scan and have a complete list of the available wireless networks in your area. With this information you can choose the Wi-Fi network you wish to connect to or quickly find the one that interferes with yours. NetSpot offers the best WiFi scanning features among all WiFi scanners for Mac and (unlike some others) the Discover Mode is available in the completely free edition of NetSpot.
NetSpot is a comprehensive WiFi network scanner that can provide a wealth of useful information to help you learn more about nearby WiFi networks and troubleshoot various problems. If you’re new to network scanning, you might have trouble making sense of all the information provided by NetSpot, which is why we’ve decided to create this brief summary of the most important information you will come across when using NetSpot.
Service Set Identifier (SSID) is broadcast by wireless routers to announce the presence of a network. An SSID is for all intents and purposes the name assigned to a WiFi network. It can be zero to 32 bytes long, and it’s typically human-readable, such as the name of the internet provider followed by the surname of the customer. Many people like to give creative and funny names to their WiFi networks, like “It Hurts When IP” or “FreeViruses.”
Not all WiFi networks broadcast their SSIDs for a variety of reasons, with security usually being among them. A WiFi network that doesn’t have any SSID is called a “hidden network”. NetSpot automatically reveals the presence of hidden networks, giving a complete picture of all WiFi activity around you.
A single WiFi network can consist of many different access points. While this arrangement is less common when it comes to home networks, businesses and organizations couldn’t function without it. The presence of multiple access points creates the need for identifying the access point from which a data packet has originated. This is where an identifier called a basic service set identifier (BSSID) comes in.
The BSSID is the MAC address of the wireless access point (WAP), and it combines the 24-bit Organization Unique Identifier (the manufacturer's identity) and the manufacturer's assigned 24-bit identifier for the radio chipset in the WAP. The BSSID can help you determine the legitimacy of a WiFi network and avoid evil twin attacks, in which an attacker creates a fraudulent wireless access point that appears to be legitimate but is set up to eavesdrop on wireless communications.
The WiFi signal is split into multiple channels, which are akin to the lanes on the highway. In North America, the exact number of channels is 11, while in most of the world, the number is 13. WiFi channels are important because they help prevent signal interference, but they work as intended only when properly configured.
Ideally, you should configure your WiFi network to broadcast on the least cluttered channel, preferably one that doesn’t overlap with adjacent channels: Channels 1, 6, and 11. NetSpot is a capable WiFi network scanner that can perform WiFi channel analysis and instantly reveal the least cluttered channel.
WiFi networks are broadcast in two frequency bands: 2.4 GHz and 5 GHz. The 2.4 GHz frequency band is split into 14 different channels (not are channels are available in all parts of the worlds), with all channels spaced 5 MHz apart from each other except for a 12 MHz space before channel 14. The 5 GHz frequency band is split into much more channels than the 2.4 GHz frequency band, with each channel being 10 to 160 MHz wide.
Higher frequencies don’t penetrate solid objects nearly as well as lower frequencies, and the same holds true even when it comes to WiFi frequency bands. Modern WiFi routers often broadcast simultaneously on both frequency bands to achieve the best signal strength possible.
To prevent unauthorized access, it has become a common practice to encrypt WiFi networks using several available WiFi encryption standards, including Wired Equivalent Privacy (WEP) and Wi-Fi Protected Access (WPA). WEP is the older of the two standards, and it’s now considered to be obsolete because WEP-protected WiFi networks can be cracked in the matter of minutes with tools that are readily available for download online.
WPA is far more secure than WEP, especially when it comes to its last two versions, WPA2 and WPA3. WPA2 is by far the most commonly used WiFi encryption standard today, but WPA3 is expected to overtake it in the near future. As a rule of thumb, you should always use the strongest WiFi encryption standard your router supports.
Emitted together with data packets is information about the vendor of the WiFi router from which the packets originate, such as Cisco, Netgear, Linksys, D-Link, or Asus.
The IEEE 802.11 standard for implementing wireless local area network (WLAN) WiFi computer communication in various frequencies is constantly evolving to satisfy the demand for high data transfer speeds, low latency, and wide coverage. Today, the most commonly used WiFi standards include 802.11ac, 802.11n, and 802.11g, with 802.11ac being the most advanced.
However, there are already WiFi routers with support for 802.11ax, a next-generation WiFi standard that aims to provide 4x the throughput of 802.11ac at the user layer.
WiFi signal strength is measured in dBm, which is a logarithmic unit of level used to indicate that a power ratio is expressed in decibels (dB) with reference to one milliwatt (mW).
NetSpot displays the minimum, maximum and average signal strength, and it can also plot signal strength on a graph to help you identify signal strength drops, which could be a sign of interference.
To obtain accurate results when scanning WiFi networks with NetSpot WiFi scanner, you should keep your laptop still otherwise the movement of your laptop may influence the results. When measuring and evaluating signal strength, it’s important for the surrounding environment to remain as constant as possible. Even something as simple as an opened window can affect the strength of the measured network.
When creating a WiFi site survey using NetSpot, your goal is to zig-zag through the surveyed area until it’s completely covered. We recommend you always start in one corner and methodically move to the opposite one, making sure to cover as much ground as possible.
If you ever need to scan a WiFi network that you can’t get close to, you can purchase an external WiFi adapter with a strong antenna and powerful amplifier. Some WiFi network adapters have a gain of as much as 1000 mW, but you should first check your local legislation to verify that their use is legal in your country.
To scan for wireless networks make sure you have NetSpot installed on your computer and follow these comprehensive steps:
BSSID identifies Access Points and their clients. It is generated by combining the 24-bit Organization Unique Identifier (the manufacturer's identity) and the manufacturer's assigned 24-bit identifier for the radio chipset in the WAP. Thanks to this unique identifier you will know whether a WiFi network is legitimate or not.
A WiFi signal is split into channels. In North America the number of channels used in wireless connection is 11. Getting on a channel that is not crowded helps avoid interference and get a better signal.
A frequency band is an interval in the frequency domain, within the limits of a lower and an upper frequency. WiFi signal is broadcast on two frequency bands: 2.4 GHz and 5 GHz. Each band is split into multiple channels that are used by various wireless networks.