I was never allowed in, but at a previous employer we had a scif onsite that had no internet in that room, and nothing was allowed out (except by a very painful

I was never allowed in, but at a previous employer we had a scif onsite that had no internet in that room, and nothing was allowed out (except by a very painful process involving a briefcase, handcuffs, multiple people, etc). Needless to say none of the computers in the scif has internet. Keeping them updated was surprisingly simple - we could bring updates in, we just had an increasing stack of USB drives and hdds that never left lol.