Both yours and tedunangst example (SSH) have one important commonality which is not present in IP: they become immediately available to two parties as soon as these two parties upgrade.
With IP, all the intermediate nodes need to upgrade to use the new protocol (tunneling tricks aside).
This difference would probably be a significant factor in the speed of adoption. Tunneling obviously can emulate the 2-party model, but then we're left with the problem of managing the crazy amount of tunnels (and security issues) and sunsetting them.
With IP, all the intermediate nodes need to upgrade to use the new protocol (tunneling tricks aside).
This difference would probably be a significant factor in the speed of adoption. Tunneling obviously can emulate the 2-party model, but then we're left with the problem of managing the crazy amount of tunnels (and security issues) and sunsetting them.
Now if the ideas like http://tools.ietf.org/html/draft-vandevelde-idr-remote-next-... were discovered/implemented a decade ago - could that have been used to turn an N-party transition problem into a 2-party transition problem ?