On Oct 17, 2005, at 2:24 PM, Tony Li wrote:
To not even *attempt* to avoid future all-systems changes is nothing short of negligent, IMHO.
On Oct 17, 2005, at 2:17 PM, Randy Bush wrote:
and that is what the other v6 ivory tower crew said a decade ago. which is why we have the disaster we have now.
and there I would agree, on both points. now, the proposal put forward lo these many moons ago to avoid any possibility of a routing change was, as I recall, Nimrod, and the Nimrod architecture called for variable length addresses in the network layer protocol and the use of a flow label (as in "IPv6 flow label") as a short-form address in some senses akin to a virtual circuit ID. There has been a lot of work on that in rrg among other places, but the word from those who would deploy it has been uniformly "think in terms of an incremental upgrade to BGP" and "maybe MPLS will work as a virtual circuit ID if we really need one". As you no doubt recall all too well, the variable length address was in fact agreed on at one point, but that failed for political reasons. Something about OSI. The 16 byte length of an IPv6 address derived from that as well - it didn't allow one to represent an NSAP in IPv6, which was an objective. So the routing problem was looked at, and making a fundamental routing change was rejected by both the operational community and the routing folks. No, IPv6 doesn't fix (or even change) the routing of the system, and that problem will fester until it becomes important enough to change. But lets not blame that on the "ivory tower folks", at least not wholly. We were all involved.