With the spread of smart devices, all networked and in many cases also connected to the Internet, it can be useful and interesting to have a general overview so that we can see how many of them are connected, what they are and if there are any intruders or problems.
Firstly, it is essential to know what devices and software are used in the company, to have an accurate and up-to-date list of hardware and software.
The second rule is to know who can access what resources, again having up-to-date documentation on this will be useful to check if anyone has accessed unauthorised resources.
With this information, using simple network scanning programmes, you can figure out what and who is connected; you can also use the router's control panel to do this. If you find a suspicious individual or access, investigate further and possibly block these accesses.