On Tue, Dec 7, 2010 at 10:43 AM, Lamar Owen <lowen at pari.edu> wrote: > On Tuesday, December 07, 2010 10:32:32 am Tom H wrote: >> Is 172.16.10.72 a private address of yours or of your ISP? > > More to the point; do you have a route to his address? I have a route to his dsl router, which, assuming that the ipv4 and ipv6 firewalls are as good at allowing/disallowing access, makes his current ipv4 and his future ipv6 addresses equally accessible.