> The statement I was responding to was "the idea that a prefix can be > changed at a whim is just a fantasy.". The point is that arbitrary & > random prefix changes are reality and believing it doesn't happen is the > fantasy.
Okay, let me rephrase that: The idea that a prefix can be changed at a whim without having a serious impact on the reliability and performance of applications is just a fantasy. People who think that DNS is a sufficient replacement for stable IP addresses haven't actually bothered to look at how poorly DNS works, how ambiguous and unstable DNS names can be in practice, how quickly apps could expect to recover from address changes (especially when the zone servers themselves have moved). Nor have they investigated the burden of expecting apps to implement explicit app-level acks for everything that gets sent over a TCP stream (so that the app can recover from a connection broken by renumbering), because without such acks the app doesn't know how much data has actually been read by its peer. > While it is nice to believe that providers that do this are > subject to customer retaliation, where are the customers going to go? If > the SP otherwise provides the best service available (or increasingly > the only service), the renumbering even is a fact of life. I don't disagree with that - in fact I currently have to live with an BRI ISDN connection to my house because no provider that can provide higher bandwidth is willing to give me a stable IP address. But just as we cannot force providers to be reasonable, neither can we force applications to work under unreasonable conditions. The best we can do is to try to define what is reasonable and what is unreasonable. Keith -------------------------------------------------------------------- IETF IPng Working Group Mailing List IPng Home Page: http://playground.sun.com/ipng FTP archive: ftp://playground.sun.com/pub/ipng Direct all administrative requests to [EMAIL PROTECTED] --------------------------------------------------------------------
