I enjoy Jack Bauer's adventures, and I'm pretty good with suspension of disbelief, but please.
ONE firewall that controls/limits access to ALL of our infrastructure systems?
The clumsiest exposition EVAR.
"Gee, Jack, we both know this information about the current plot, but let me just say it awkwardly for the benefit of the stupid viewer."
"No problem, Chloe. By the way, did you know that I tortured people and I'M NOT SORRY, even though I've said that twice in every episode so far?"