S Woodside wrote: > ... > 44 bits are provider independent and encode GPS coordinates. > It's enough to have accuracy to roughly 10 meter squares. The 04 version reduced that to 6.4 m, but your point about it being somewhat course is valid. I stopped at 44 bits because the goal was creating a /48. If that is expanded to a /52 you are looking at > .5 m resolution. While this is possible to encode, the publicly available gear is not capable of measuring that accurately. > BUT ... that doesn't consider altitude. Depending on the intended use, that can be further encoded in the remaining bits to create a unique /64 per cubic .5 m, 2 km deep. > In addition, it's quite easy to see that 10 > meter squares may be a little bit too big for some purposes, even if > you're just talking about individual homes. Also, it doesn't > provide a > mechanism to define an area rather than a point. I could go on. > > So it's clear at least to me that under this scheme there is > not enough > space in IPv6 to do proper justice to georouting. We have the option of using longer than /64 prefixes if necessary. I would prefer not to go there, but given a unique need it could be done. Tony > > simon > > > [1] http://www.ietf.org/internet-drafts/draft-hain-ipv6-pi-addr-04.txt > > > -- > www.simonwoodside.com -- 99% Devil, 1% Angel > >