My friend is on an uni where most of the ports are blocked so he can't even play games online, 80 is open obviously. The idea is "I will set up VPN tunnel on :80 on my router, so you should be able to connect to it and we can happily play again".
Now I wonder how much is this likely to fly...? What are the potential/usual obstacles here? (Besides the fact that I get annoying warning messages in the log.) Is it safe to say that when my friend can reach my webserver the VPN will work as well?
1 Answer
Two problems:
The additional latency added by the VPN may still prevent online game playing (e.g. all traffic will have to go to your home, thorough VPN, and then back to the Internet).
The university may have deep packet inspection firewall, or transparent proxy, on outgoing port 80 traffic, which could prevent VPN traffic on port 80. On top of it, any additional filtering at the university will add more latency...
Otherwise, don't see a reason why it wouldn't work. Common port numbers are just a convention, if you can configure a software to use an alternative port, it should work.
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