> From: Keith Moore <moore@xxxxxxxxxxxxxxxxxxxx> Love the email address... > IPv4 NATs cause problems .. because they rob applications developers of > functionality, make the net less reliable and less flexible, increase > the cost of running applications and raise the barrier for new > applications, and increase the effort and expense required to > troubleshoot problems. These things may or may not have been perfectly understood a priori by those who deployed NATs, but my sense is that even if the world had to do it all over again, they'd do it all again, for a simple reason: these costs of NAT were outweighed by the benefits of NAT (allowing network expansion with little additional coding/engineering/deployment investment; also, it allowing other higher bang/buck things, such as advanced Web stuff, to be done, by allocating that effort elsewhere). > NATs don't cause us problems because they violate principles, they > cause us problems because they break things. But the fact that the > principles were being violated by NATs, was a clue that significant > problems might result from their use. Sadly, many people ignored those > clues because they didn't trust arguments that appealed primarily to > principle... and by the time the actual problems were well-understood, > it was too late. The first part of this I concur with, but not your conclusion; see the previous comment. Noel _______________________________________________ Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf