We did the same thing... It seems easiest from a management perspective to copy the ipv4 logical layer with v6. The only change on our side was the fixed prefix length which if anything was a nice change. We did run into a few devices (old layer 3 switches) that don't support ipv6 and on those we either did not deploy IPv6 or moved the routing off for both v4 and v6 to the nearest "core" router that could handle v6 for any vlans that required the v6 capability. John van Oppen Spectrum Networks LLC 206.973.8302 (Direct) http://spectrumnetworks.us -----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu] On Behalf Of Valdis.Kletnieks@vt.edu Sent: Monday, August 27, 2007 10:25 AM To: John Osmon Cc: nanog@merit.edu Subject: Re: IPv6 network boundaries vs. IPv4 On Sat, 25 Aug 2007 23:56:29 MDT, John Osmon said:

Is anyone out there setting up routing boundaries differently for IPv4 and IPv6? I'm setting up a network where it seems to make sense to route IPv4, while bridging IPv6 -- but I can be talked out of it rather easily.

We decided to map our IPv6 subnets one-to-one to our IPv4, so each of our routed /22 to /27 subnets gets a /64 IPv6 prefix. This however was just due to the fact that our topology permitted that - your mileage may vary.