On Sat, 31 Mar 2012 19:35:05 -0500, Charles N Wyble said: > How much geographical accuracy does this imply? Just enough to indicate > where the "heart" of a network is, or was traditionally. A chunk can > represent any number from 0-65534, because it can represent up to 65535 > unique numbers and we start at 0. So, longitude can be expressed as a > number of degrees "moved east" of the prime meridian from 0-360. This > means the difference between each integer in a longitude chunk is > 360°/65535, or .005493°. At the equator, where a degree represents the > longest distance, that works out to about .4 miles [1]. For any other > latitude, however, precision is better than that. Latitude, which goes > from -90 to +90, can be represented as a 0-180 number where the equator > is at 90, which works out to .002747° precision.
I'll bite. Is 60 Hudson 0.4 miles wide? > I'm not sure what to make of it. Seems like someone trying to re > establish classful addressing and not understanding routing, subnets, > managed networks etc. No, it's somebody trying to re-invent geographical routing and not understanding yadda yadda yadda. The traceroute from my apartment to my office, a 20 minute bike ride iin the real world: traceroute -A 192.70.187.198 traceroute to 192.70.187.198 (192.70.187.198), 30 hops max, 60 byte packets 1 192.168.2.1 (192.168.2.1) [AS8151/AS28513] 1.491 ms 1.452 ms 3.909 ms 2 71.62.120.1 (71.62.120.1) [AS21508] 18.133 ms 18.203 ms 37.221 ms 3 te-8-2-ur01.blacksburg.va.richmond.comcast.net (68.85.71.97) [AS20214] 18.002 ms 17.986 ms 17.959 ms 4 te-8-3-ar01.staunton.va.richmond.comcast.net (69.139.165.161) [AS33287] 21.101 ms 21.075 ms 21.047 ms 5 te-8-1-ar01.chesterfield.va.richmond.comcast.net (68.86.173.165) [AS21508] 29.087 ms 29.089 ms 29.029 ms 6 te-0-1-0-0-cr01.charlotte.nc.ibone.comcast.net (68.86.91.113) [AS7922] 38.882 ms 46.911 ms 46.916 ms 7 pos-3-14-0-0-cr01.atlanta.ga.ibone.comcast.net (68.86.85.213) [AS7922] 43.328 ms 45.617 ms 45.602 ms 8 nyc-e5.nyc.us.net.dtag.de (68.86.88.186) [AS7922] 45.585 ms 45.563 ms 45.540 ms 9 te4-2.ccr01.atl02.atlas.cogentco.com (154.54.10.233) [AS174] 42.049 ms 42.978 ms 42.959 ms 10 te0-0-0-1.ccr21.atl01.atlas.cogentco.com (154.54.0.165) [AS174] 41.061 ms 41.088 ms 41.097 ms 11 te0-5-0-7.ccr21.dca01.atlas.cogentco.com (154.54.42.193) [AS174] 40.750 ms te0-0-0-7.ccr21.dca01.atlas.cogentco.com (154.54.28.213) [AS174] 40.914 ms te0-0-0-3.ccr21.dca01.atlas.cogentco.com (154.54.28.201) [AS174] 40.878 ms 12 te0-1-0-5.ccr21.iad02.atlas.cogentco.com (154.54.2.50) [AS174] 40.638 ms te0-1-0-1.ccr21.iad02.atlas.cogentco.com (154.54.26.130) [AS174] 40.195 ms te0-3-0-5.ccr21.iad02.atlas.cogentco.com (154.54.41.230) [AS174] 43.299 ms 13 38.127.193.146 (38.127.193.146) [AS174] 43.281 ms 43.171 ms 43.208 ms 14 isb-7606-1.vl155.cns.vt.edu (192.70.187.148) [AS1312] 48.902 ms * * Quite the little trip - north to Staunton, south to Atlanta, north to DC, south to B'burg again, and I dunno WHAT happened at hop 8. :) Every single person who suggests geographically-based routing or addressing fails to understand that there's no cable connecting AS21508 to AS1312. And there's likely to never be one (we invited all the local providers to peer, several did accept because it lowered their upstream transit costs, Comcast apparently didn't see the added complexity as being worth the infinitesmal savings it would get them at their Cogent interconnect). So sending packets to 21508 because it's geographically "close" and hoping it will get to 1312 (or vice versa) is a fool's errand. And if you're not basing routing decisions based on the geographic address, who *cares* if the address reflects location? At that point, you're much better off basing my IP address off the fact that I'm a Comcast customer and Comcast probably knows how to get packets to me. I'll overlook the little detail that trying to use latitude and longitude as the basis for IPv6 addresses ends up wasting literally an entire Pacific's worth of address space. ;)
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