cost of dual-stack vs cost of v6-only [Re: IPv6 on SOHO routers?]

Thu Mar 13 15:46:28 UTC 2008

> I don't know why Leo thinks so, but even I can observe the 
> "extra recurring support cost of having to work through two 
> stacks with every customer that dials in" as being far 
> greater than any technology costs in either single-stack 
> scenario.  The 'recurring' part is the real killer.

This is why any ISP that has not moved their core network
over to MPLS, really needs to take a serious look at doing
so now. If you do this then you only really need to support
IPv6 on your edge routers (MPLS PE) which are used to connect
IPv6 customers. Those PEs will use 6PE to provide native IPv6
to your customers.

Dual stack is not the only solution.

Note that it is also possible to use something like GRE tunnels
over IP4 to build an IPv6 overlay. Depending on the scale of
your network (and your capital budget) this may also be an 
attractive way to ease into IPv6 without changing everything.

There is a whole smorgasbord of choices to make. It's not an
easy slam-dunk proposition and you can't just find someone
to tell you how to handle your network situation. It's not
like the early 1990's when you could get away with following
the crowd.

--Michael Dillon