Very nice utopia you live in, DC Guy...but you certainly don't manage large groups in a large company. Trust is wonderful...absolutely, no question. But if you are being paid to do job, and hired/retained with an expectation of NN hours/week-day, then your employer most certainly can and will track, at some level, whether or not you are holding up your end of the bargain. The OPs request for high level monitoring is simply an adjunct to the existing monitoring. That being the monitoring done by team leads/managers/supervisors...and peers. Yes, peers! "Hey Boss, whyinhell can DCGuy come in at 10 and leave at 2 every day, do no more work than anyone else here, and get away with it??" "I didn't know he was doing that" "Bloody hell, you call yourself a manager and don't when your people are coming and going?"
Face it, nirvana is a nice dream...the OP is asking for practical assistance for the real world.
And, to the OP, assuming you are in a windows world, logging domain logons/logoffs should be a very simple solution for you at a high level.
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