Not sure what you mean by "their own version of internet", but access to any means of trans-border communication was indeed restricted.

As to computers - it's not like you could walk into a store and buy one, they simply didn't produce them in quantity (central planning economy took a while to recognize that need). But if you could find one, access was not particularly restricted. You could also build a simple home computer yourself if you were into electronics. Schematics were published in hobby magazines and it was a cool thing to do, not something frowned upon by authorities.