USB Virtualizer logging question

So I enabled basic USB logging on the USB Virtualizer. Questions though...

The "LogonID" in the log, is it associated with an account? a thin client? or just a random ID generated each time someone logs in?

For example the line like...
"Logon Session Data -> logonID 00000000:0202b2c8"

Is "00000000:0202b2c8" unique to anything? or is it just a randomly assigned number?