Who knows the applet for displaying network connection activity in the form of an icon when the computer has not yet been logged in?

Question

linux

So that the applet or tool allows you to display network activity / inactivity as an icon before authorization into the computer or when it is locked. Authorization of workstations is configured over the network. On Cent OS 6.6 to go.
For example, the workstation booted up, reached the authorization, and below the network connection activity in the form of an icon.

Answer 1

For some reason it seems to me that you are solving a slightly different problem, such as "how to warn the user that the machine is offline so that he does not waste time on fruitless login attempts."
On the subject: it will not be easy on bare CentOS. But in general the problem seems to be solved:
1) KDE has widgets on the lock screen
https://www.maketecheasier.com/customize-kde-lock-...
2) Something like conky can be made to work from the lock screen through the screensaver
Bad example, for ubuntu and xscreensaver
askubuntu.com/questions/543646/how-to-get-conky-wo...