How to wish you hadn't forced ipv6 adoption (was "How to force rapid ipv6 adoption")

Mark Andrews marka at
Fri Oct 2 05:10:10 UTC 2015

In message <560E0C44.5060002 at>, Rob McEwen writes:
> On 10/2/2015 12:18 AM, Mark Andrews wrote:
> > A hoster can get /48's for each customer.  Each customer is technically
> > a seperate site.  It's this stupid desire to over conserve IPv6
> > addresses that causes this not IPv6.
> In theory, yes. In practice, I'm skeptical. I think many will 
> sub-delegate /64s
> Plus, nobody has yet addressed the fact that new /48s will be just so 
> EASY to obtain since they are going to be plentiful... therefore... the 
> LACK of scarcity will make hosters and ESP... NOT be very motivated to 
> keep their IP space clean... as is the case now with IPv4.

The brakes are already in place at the RIR level.  At this level
you can't just get more /48's with no accountability.

> Also, it seems so bizarre that in order to TRY to solve this, we have to 
> make sure that MASSIVE numbers of individual IPv6 IP addresses.. that 
> equal numbers that my calculate can't reach (too many digits)... would 
> all be allocated to one single combined usage scenario. Then allocating 
> only /48s multiples that number by 65K. Mind boggling

There are 281474976710656 /48's.  That is what you manage, not IPv6
addresses.  It's also most probably got more digits than you
calculator supports. :-)

Stop thinking addresses and start thinking sites.  We went to 128
bit of addresses so that we could stop worrying about individual
address, the sizes of subnets or working out how many addresses a
site needs when handing out address blocks except in the most extreme


> -- 
> Rob McEwen
> +1 478-475-9032
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka at

More information about the NANOG mailing list