David Conrad wrote: > Tony, > > On Sep 13, 2007, at 5:29 PM, Tony Hain wrote: > > David Conrad wrote: > >> .... > >> IPv6 _is_ IPv4 with more bits and it is being deployed that way. > > No it is not, and you need to stop claiming that because it > > confuses people > > into limiting their thinking to the legacy IPv4 deployment model. > > I'm not particularly interested in getting into a "Yes it is! No it > isn't!" debate. I will merely point out that IPv6 has been > implemented and is being deployed as IPv4 with more bits. As I said, > you can argue it shouldn't be this way, but reality often sucks. I am not looking for a never-ending debate either. What people are overlooking is that part of any viable transition plan is to allow people to deploy the new widget in a way that they understand and are comfortable with. The fact that people -can- deploy IPv6 the same way they deploy IPv4 is a feature, not a requirement that they actually deploy it that way. Statements like yours only confuse people because they take it literally rather than in context that current deployments are not looking at the protocol differences beyond 'more bits'. When people start from the perspective that 'the names both start with IP and they are both packet delivery systems but they are different protocols' then find the similarities, they are much better off than when they start from the 'just more bits' perspective. > > I might suggest that the reason why major core infrastructures like > the telephony system, utility grids, etc. are often hodgepodges of > hacks and kludges is because the business case to throw out > successful deployment models and existing plants is difficult to > make. And when you do, you generally want to insure a high level of > backwards compatibility so that you don't have to change everything > to make use of the new bits. Either you need backwards compatibility, or you need the ability to support both until the old systems die off naturally. There was plenty of time to support both for a graceful transition, but people seem to want to wait until they are forced to change before they start, so the actual shift will be ugly and costly. > > > There are way too many arguments > > (even on this list of relatively smart people) where the fundamental > > difference of simultaneous use of multiple addresses is the key to > > thinking > > differently between the versions. > > Can you point to one widely used application, API, or operating > system (that doesn't require manual intervention) that supports this? > The applications you are looking for can't exist or be economically supported in IPv4/nat, so they have yet to make it to the market place. That does not mean 'we must restrict IPv6 deployments to match IPv4', even if the initial deployments are happening that way. There is a strong tendency to only worry about supporting current applications, but we really need to be building a framework to allow new applications to appear that failed economically in the past. While IPv4 is a good protocol, the general attitude that 'if it can't be done with IPv4 it is not worth doing' needs to go away. Tony _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf