Network Utility

Network Utility was an application included with macOS up to MacOS Catalina that provided a variety tools that could be used related to computer network information gathering and analysis. Starting with macOS Big Sur the application is no longer included.
Network Utility shows information about each of your network connections, including the Mac Address of the interface, the IP address assigned to it, its speed and status, a count of data packets sent and received, and a count of transmission errors and collisions.
Services.
The available services or tools found in the Network Utility:
Actionable Items.
Examples of what the Network Utility can help with:
Port scan information.
Network Utility uses the tools supplied in the unix directories for most of its functions, however for the port scan it uses a unix executable in its resources folder, stroke, found at Network Utility.app/Contents/Resources/stroke.