On 11/13/08 10:06 AM, Hallam-Baker, Phillip allegedly wrote: > > I beleive that the question would not arise If we had a coherent > Internet architecture > > The idea that an application can or should care that the IP address of a > packet is constant from source to destination is plain bonkers. It was > no an assumption in the original Internet architecture and should not be > an assumption that any application should rely on. That's not the problem. The issue is location. Once we have established a session then how the packets are labeled for network layer purposes doesn't matter much (modulo security) but how do we get communications set up in the first place? Suppose I want to reach "foo". Who do I ask to find a locator for him? Split DNS works fine when there are just two states, inside and outside -- a DNS server can be configured to know how to respond in each case. But if you were to sprinkle NATs all over the Internet there would be no place that could give a confident answer about how I, over here, should name foo in the network layer in order to get a packet to him, and have that answer get to me in the correct form. So it is very important to understand where we think it might be safe to put what kinds of NATs. swb _______________________________________________ Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf