Re:A list of ways to “Break the Internet” for the 48 hours b...
by Retric on Tuesday December 12, 2017 @08:45PM
(#15911317)
It's a little more insiduis than that. They don't want to make it clear by blocking things what they can and can't track. Instead they degrade service from things they have little control over to things they do.
In Wireshark, normally you'll see flurries of variable-sized traffic across 53 then either 80 or 443. But for a VPN, you just see a constant flow of boring packets over 500.
Why doesn't China's national firewall block port 500? Possibly because it would also block the personal VPNs of the leadership of the Chinese government.
(Edits for clarity)