On Thu, Oct 21, 2010 at 8:07 AM, Ben Butler <ben.but...@c2internet.net> wrote: > Hi, > > Showing my ignorance here, but this is one of the things I have wondered, > given that we run both v4 and v6 for a period of time on the Internet, > presumably at one time or another a particular resource may only be able in > v4 land, then v4 and v6, then finally v6 only. > > I have never been particularly clear how an end network that exists only in > v4 or v6 address space is able to access a resource that only exists in the > other. Is can sort of see some freaking huge NAT box type thing that > summarizes v6 in a v4 address scope or contains the v4 address range at some > point inside the v6 address space - but how can a v4 host get to a hot in v6 > world that sits outside this without going through some form of proxy / nat > gateway between the two. > > Or are the two simply not inter-communicable? > > Ben > > -----Original Message----- > From: Patrick Giagnocavo [mailto:patr...@zill.net] > Sent: 21 October 2010 15:59 > To: Owen DeLong; NANOG > Subject: Re: Only 5x IPv4 /8 remaining at IANA > > On 10/21/2010 4:28 AM, Owen DeLong wrote: > >>> Actually for those of my clients in one location, it served as an >>> impetus to extend a contract with Level3 for another 3 years - with >>> their existing allocation of a /24 of IPv4 addresses included. >> >> All well and good until some of their customers are on IPv6... >> Then what? > > I'm sorry, can you expand on exactly what you mean by this? > > Are IPv6 connected machines unable to access IPv4 addresses?
IPv6->IPv4 is called NAT64, and it works today pretty well. Most things work very well (web, email, ...), somethings don't (skype ..) http://www.youtube.com/watch?v=AmjlptEva4Y#t=1h32m26s http://tools.ietf.org/html/draft-ietf-behave-v6v4-xlate-stateful-12 http://ecdysis.viagenie.ca/ As your major NAT vendor, they probably have NAT64 in the road map for the next 6 to 12 months. IPv4->IPv6 initiated connection are a lost cause that cannot scale in any good way. Cameron