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

Rob McEwen rob at
Fri Oct 2 06:09:00 UTC 2015

On 10/2/2015 1:10 AM, Mark Andrews wrote:
> or working out how many addresses a
> site needs when handing out address blocks

At first, I'm with you on this.. but then when you got to the part I 
quoted above...

it then seems like dividing lines can get really blurred here and this 
statement might betray your premise. A site needing more than 1 
address... subtly implies different usage case scenarios... for 
different parts or different addresses on that block... which could slip 
back into... "you blocked my whole /48... but the spam was only coming 
from this tiny corner of the block over here (whether that be a one IP, 
a /64, or a /56)... and now other parts of the block that were sending 
out legit mail, are suffering".

Likewise, sub-allocations can come into play, where a hoster is 
delegated a /48, but then subdivides it for various customers.

Rob McEwen
+1 478-475-9032

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