On 31 maj 2010, at 03.39, Mark Andrews wrote: > And have any of those that say this tried: > > 1) tried dual stack > 2) tried IPv6 only through NAT64 (NAT-PT) > > with a sample of customers or are they just talking without any > reference points. I am spending lots of my time trying to get some _real_data_, but I do not have it yet. I am though running dual stack with native IPv4 and native IPv6 in my home office, on all my servers, and have quite some experience on dual stack. And that was not as fun as I expected. I.e. my data is based on dual stack be worse than I expected, and having people asking me "would native IPv6 only be better", or "what about native IPv6 with NAT64/DNS64". And I have also read various papers people in IETF have written on how to handle the quite normal case with SMTP where MX records are in use (which have been far from complete), and then maybe IP6 or IPv4, and IPv6 or IPv4 for DNS transport, and quite often search paths in DNS as well... The number of DNS lookups needed explode exponentially, you get timeouts on application layer, applications show timeout boxes as if the mail server is not responding when in reality multiple seconds are used for DNS lookups. It is messy with dual stack. Messier than what I think many people think. Including me (and I thought I had quite good overview of how it worked). > Runing dual stack internally without external IPv4 connectivity is > just as bad as running dual stack internally without external IPv6 > connectivity. You just don't want to go down that path. I claim it is worse than having IPv6 only. > Yes. I've tried to run IPv6 only. Real IPv6 only, IPv4 completely > disabled in the OS. It wasn't fun. So have I. For example at the IETF in Anaheim one morning when IPv4 connectivity was broken. For me it worked better than dual stack, when accessing things that was reachable over IPv6. But that was with my OS (MacOSX) that have relatively good IPv6 support. So there are good things and bad things with both dual stack and IPv6 only. And no, we do not have any data, but we do not have good documents on how to run dual stack either. Patrik
Attachment:
PGP.sig
Description: This is a digitally signed message part
_______________________________________________ Ietf mailing list Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf