The place where I did my internship used electronic keys that one would have to activate when coming into work each day (at least one of those little wall mount

The place where I did my internship used electronic keys that one would have to activate when coming into work each day (at least one of those little wall mounted stations (not much bigger than a fire alarm trigger) for that purpose on each floor in the stairwells). It would then stay active and capable of opening doors for ~8 hours, ie. a normal work day. Also, a nifty feature of these things as explained to me by the on-site guy dealing with electronics (including the management of these keys): these keys could be managed in different ways, e.g. grouped for departments, grunts vs. managers etc. AND the settings didn't have to be flashed to every single key or every single activation station, but instead flashed to one key (like the one of this employee) who then went around to a couple of stations and "activated" his key again, thereby transferring the updated/new setting(s) to the station which would then update every key inserted into it etc. etc. Meaning the key management was quite literally "viral".