It isn’t the first time someone built a heavily trapped, walled and patrolled border of that size.
Take a look at the Inner German Border. It was over 1300 km (approx. 810 mi) long, and was (average) about 5.5 km wide (a bit more than 3 miles).
From 1974 to 1979, 4956 people attempted to cross it, and only 229 (4.6%) actually made it.
Edited my comment to fix, thanks!
This is less of a source and more like a compilation of resources, but for anything spacecraft related I can always recommend Atomic Rockets. For this specifically, the page on Heat Radiators.
amateur radio was illegal to encrypt
Amateur radio is still illegal to encrypt (with some exceptions for controlling satelites), because private communication isn’t the point of amateur radio.
Besides, (in most countries) there are some topics that are illegal to talk over amateur radio about, mainly stuff like politics and religion. You’re also not allowed to offer telecommunication services (i.e. pass messages on for others). Enforcing those sorts of laws would be impossible with encryption.
But to answer your question: I think we probably wouldn’t have had an internet. Authoritarian regimes thrive on stability and maintaining the status quo, I think someone high up would have quickly decided that developing that sort of tech is too risky.
Depending on the language, there might exist an automated tool for generating those kinds of diagrams from code.