This question arose from a dispute with a friend of mine. Over the last few weeks, I've encountered an odd phenomenon. All my connections are never torn down when I disconnect from the Internet. Even ssh sessions stay intact across reconnects. How is that possible?
The answers here state it is perfectly normal. Then the question is: why do get TCP connections always lost for some people after reconnecting to the internet even without NATs in between, which is the case with the friend of mine. Other than the internet provider, both setups are comparable: Linux over dial-up.