There's a project called SCION [1] that (among other things) does roughly this. In essence, participants announce their presence over a multicast-type protocol,

There's a project called SCION [1] that (among other things) does roughly this. In essence, participants announce their presence over a multicast-type protocol, and in order to send packets to anyone, you must have received a recent announcement from them. It's a quite fascinating re-imagination of the Internet, solving many of its problems (and probably introducing a whole slew of new ones). [1] https://www.scion-architecture.net/ https://www.scion-architecture.net/