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This isn't how badge readers work. Every controlled door is wired to a relay panel. That panel connects to a access control db - but it always maintains a cache

This isn't how badge readers work. Every controlled door is wired to a relay panel. That panel connects to a access control db - but it always maintains a cache that is very slow to expire... because the manufacturers weren't clueless morons.

kamaal 5y ago
>>cache that is very slow to expire... People have been WFH/Remote working for a while now. Like 1.5+ years. Besides when everything runs fine it all feels magic. You discover how things can break in a situation like this. Im pretty sure they are now rushing to restore access for every FB employee to their buildings.
cududa 5y ago
Except some of the readers were made in house. I’ve never been into a Facebook conference room that didn’t use one of their custom touch screen/ card readers.
- sennight 5y ago
  That isn't access control, that is a an intern project. Those readers aren't wired to devices that could trap you in a burning building, they simply provide a rube goldberg solution to the traditional sign-in sheet.
cromka 5y ago
> Every controlled door is wired to a relay panel. That panel connects to a access control db Absolutely not. E.g. HID is a well-documented protocol and you can do whatever you want using the RS232 interface they come with (depending on the model). I personally wrote a gateway that would dynamically and directly check the access with my own software.
- sennight 5y ago
  lol, California fire code makes no exemptions for python projects... this whole story has a "virgins talking about sex" vibe.