cb.list6 wrote: > I think there is something here that is interesting, and that is the > interplay between paper design, evolution, and ultimately the emergent > complex dynamical system we call the internet ... which is almost > completely zero compliant to the e2e principle. Not that e2e is the wrong > principle, but ipv4 could not support it as of 10+ years ago. As long as a NAT box is directly connected to the Internet and is UPnP capable, which is the case at my home, hosts behind it can enjoy full end to end transparency (PORT command of FTP works), if hosts' IP and transport stack is modified a little. > Hence, nearly > every internet node is behind a stateful device (cpe or cgn nat) That is not a problem if state of the device is known to the end, because IP and transport stack of the end can reverse the translation. See draft-ohta-e2e-nat-00.txt for details. > or server > load balancer. There is also widespread disbelief in how dns operates in > the real world (not everyone gets the same answer). It has nothing to do with the end to end transparency. If operators of the servers think any server is fine, it is not a problem. Masataka Ohta >