Path: csiph.com!eternal-september.org!feeder.eternal-september.org!mx02.eternal-september.org!.POSTED!not-for-mail From: Stefan Monnier Newsgroups: comp.os.linux.networking Subject: Re: How could I get a connection to an UDP port through two NATs that I don't own? Date: Tue, 31 May 2016 22:10:21 -0400 Organization: A noiseless patient Spider Lines: 18 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain Injection-Info: mx02.eternal-september.org; posting-host="8b378fb4d95e00460053ffde5fd4ffd8"; logging-data="6556"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19mliezFuxbRsUg5l2vgdvw" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.1.50 (gnu/linux) Cancel-Lock: sha1:CxH19kDlLy1qbAoOBFdZCeEE6yU= sha1:buTbzxJY05rtRJTMxwp+phrKPyo= Xref: csiph.com comp.os.linux.networking:3789 > I don't know the answer; just wanted to boil down the question. It > feels like you need at least one more host with a public address to > pull this off. And some kind of tunneling. That's right. ID do it as follows: - get a server machine somewhere on the internet (your home, your office, or some VPS hosting somewhere). - run an OpenVPN server on that server. - setup OpenVPN clients on your two UMTS-connected machines to connect to your server. - you can now talk via UDP over your very own VPN network at will. OpenVPN can run over UDP or TCP as well, and over any port (including 443), so you don't need any "passthrough" support from the NAT (IOW it works over any NAT). And it's rock-solid in my experience. Stefan