[tor-talk] Tor and PCP (Port Control Protocol)

[Anders Andersson]

Since my ISP implements carrier-grade NAT[1] (with an opt-out system)
I read a little about it and found something called the "Port Control
Protocol"[2] (PCP). Unless I am mistaken, and *if* my ISP implements
it, it seems that it could enable me to run a Tor relay on one of the
shared IP numbers.

>From what I understand it would make it possible for me to send a
message to my ISPs router saying something like "I want an external
port bound to this ip:port on my network", and it would either assign
a port on the external IP and return it to me, or deny the request. If
accepted, I could have my Tor announce that external ip:port and
everything should work as expected.

Now, before I dig in to this, I wonder if someone else has experience
with it? Any flaws with this hypothetical setup?



[1]: https://en.wikipedia.org/wiki/Carrier-grade_NAT
[2]:https://en.wikipedia.org/wiki/Port_Control_Protocol