An IP scanner is a tool that can give you vulnerable information about your network. It can scan one or more IP addresses or an entire network.
Each IP scanner tool contains its own features. An advanced scanner can manipulate the TCP handshake for fast scanning, doing it by crafting a special TCP packet.
The common feature of an IP scanner is including:
- Ability to scan a range of ports.
- Use Full TCP scan aka as connect().
- Discovering of open ports.
- Option to scan more than 1 IP address.
Basic IP Scanner:
A basic IP scanner will use the above features to scan a selected IP address. It will show back the result it a nice dashboard that will contain information related to the results. The information can from port information – like what is the default service that uses this port. To extra information like the operating system that is under this IP address.
Advanced IP Scanner:
Advanced IP address will contain the feature of a basic IP scanner and will have some more feature, it might use other scan methods, use build-in scripts for OS and service detection. Scan a full network (range of IPs). It might also extract vulnerable information from the open ports in each scanned device. Like if the device has shared folders, what are the services that the device have and so on.
What the tool can do for you?
With an IP scanner tool, you can easily scan your network to get your network topology. It can check if there are some unwanted or unknown devices connected to your network. This can be archive if you scan your network as in a range of IP addresses. Think about a unknow PC device or a small router that allow WIFI network access.
Here are some tools in that area that you should know about.
*Source of the below tool info is from the software publisher website.
Angry IP scanner is a fast and friendly network scanner for Windows, Linux, and Mac.
It is very extensible, allowing it to be used for a very wide range of purposes, with the primary goal of being useful to network administrators.
Nmap (“Network Mapper”) is a free and open-source (license) utility for network discovery and security auditing.
Many systems and network administrators also find it useful for tasks such as network inventory, managing service upgrade schedules, and monitoring host or service uptime.
Nmap uses raw IP packets in novel ways to determine what hosts are available on the network, what services (application name and version) those hosts are offering, what operating systems (and OS versions) they are running, what type of packet filters/firewalls are in use, and dozens of other characteristics.
It was designed to rapidly scan large networks, but works fine against single hosts. Nmap runs on all major computer operating systems, and official binary packages are available for Linux, Windows, and Mac OS X.
In addition to the classic command-line Nmap executable, the Nmap suite includes an advanced GUI and results viewer (Zenmap), a flexible data transfer, redirection, and debugging tool (Ncat), a utility for comparing scan results (Ndiff), and a packet generation and response analysis tool (Nping).
With Advanced IP Scanner, you can scan hundreds of IP addresses simultaneously at high speed. The software scans ports of network computers and finds HTTP, HTTPS, FTP, and shared folders. Scan your network (including Wi-Fi network) to get more information about all connected devices including computers’ names and MAC-addresses.
Free IP scanner is a very fast IP scanner and port scanner. It is intended for both system administrators and general users to monitor and manage their networks.
Powered with multi-thread scan technology, this program can scan hundreds of computers per second. It simply pings each IP address to check if it’s alive, then optionally it is resolving its hostname, scans ports, etc.
*Source of the above tool info is from the software publisher website.
About the above tools:
So as you can see there are several tools that you can use as an IP scanner tool. If you are working as a network admin or responsible for devices that connected to the network. It is recommended, from time to time, to check what is the status of your devices. If there is an unauthorized device connected. Also, it can be good to find open ports that should be closed.
Using such a tool can help you verify that there are no unknown devices that connected in your network, no unwanted ports are open, and so on.
Usage for home users:
As a home user, if you have a wireless network as most of us have those days, it can be good to use an IP scanner to check that there is no unwanted device connected to your home network using your internet. Saving money by using your network. In a more severe situation access sensitive data on your devices. Checking that can be done using one of the above IP scanner tools that were mentioned above.
We have some nice guides, on this site, that you can read to go deeper with some of the above tools. It can help you with the how-to-use question when it comes to using the tools.