---- Original Message ----- From: "Stewart Bryant" <stbryant@xxxxxxxxx> To: <ietf@xxxxxxxx> Sent: Wednesday, October 05, 2011 2:01 PM > > Tom > > "I would take issue with OSPF/ISIS and IPv4/IPv6. " Stewart See my reply to Loa for the first. For IPv4/IPv6, we are not talking about two solutions which are concurrent in any sense of the word. When the limitations of IPv4 started to loom on the horizon, work was started on a replacement, and there were several candidates, of which - thankfully - one was chosen. The issue that was not given enough attention was how to migrate the world at large from IPv4 to IPv6. As has been clearly described on the MPLS-TP list, interworking is impossible, the Characteristic Information is too dissimilar, and with interworking being impossible, migration is naturally difficult. So it is an interesting problem, and the coexistence models of s.6 of this I-D are relevant, but it is a poor fit for having two rival solutions being developed concurrently for the same problem. I use video recorders, and latterly the DVD replacement, as poster children for this issue - most people can relate to these examples without needing an in-depth knowledge of A-law or some such:-) Tom Petch > Please can you expand a little on this. > > Stewart _______________________________________________ Ietf mailing list Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf