> 6to4 is a transition technique that I would argue is not > really appropriate for a large site (i.e, one with _many_ > subnets). I.e. one with a /48 allocation from an RIR. Therefore it would appear that 6to4 is targeted at small sites such as home users who will likely receive a /56 from the RIR. Therefore Keith's concerns are warranted. > Give me a break. Use leading zeros for the first 8 bits of > the subnet part and everything else still works just fine. Are you sure of that? Can you point me to a draft or RFC where this is documented? > The biggest barrier to the success of IPv6 is the lack of a > short-term ROI. There just isn't a strong business case for > anyone to invest in deployment. It's really that simple. In two or three years, IPv4 network growth will be severely limited. Any business whose revenue growth is linked to IP network growth, must use IPv6 for this beyond two to three years from now. IN order to successfully use IPv6 for the mission critical network growth that is the engine of business revenue, they need to have at least a year of trials and lab testing in advance. That means there is not much more than a year before such businesses will have missed the boat. Some may argue that Return three years from now on Investment made today is not short term, and that is true. However, if the investment is not made today, the platform for short term ROI will not exist in three years time. That does make a strong business case and some companies are busy working behind the scenes to prepare for the disruption caused by IPv4 runout. For some, the disruptive event will be fatal and for others it will be very profitable. This message will soon reach the investment community so you will soon see investment analysts asking very tough IPv6 deployment questions, and rating stocks appropriately. That is definitely a short term ROI scenario for IPv6. Think back to the days when the OSI protocols were expected to be the next big thing, replacing IPX, DECNET, Appletalk and NetBIOS. IP was for universities and labs. In telecoms, ISDN and ATM were the wave of the future. This is the way things were in 1993. Two years later, in 1995 we were experiencing exponential growth of the TCP/IP Internet. I believe that it was something like 1500% growth in that year and dozens of new books about the Internet came on the market joining the 3 books that were on the market in 1994. It is almost certain that IPv4 runout will drive a similar upsurge in IPv6, although not quite the same magnitude. --Michael Dillon _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf