Internet Edge Router replacement - IPv6 routetablesizeconsiderations

George Bonser gbonser at
Thu Mar 10 22:34:05 CST 2011

> Of course, it does - you may have many content farms/instances, and
> taking down point-to-point links can DoS your entire set of
> farms/instances, whereas an attack against a given endpoint access
> network doesn't necessarily mean that your other
> properties/networks/services are being attacked, as well.

And I say taking down 10 such farms is no bigger problem than taking
down 10 /64 backbone links.  Same challenge. A /64 is a /64, seen one
you've seen them all. 

> There is no good reason to use /64s on point-to-point links.  It is
> wasteful (please, no more about the supposed infinitude of IPv6
> addresses; some of us reject this as being shortsighted and
> insufficiently visionary concerning eventual one-time-uses of IPv6
> addresses at nanoscale) and turns your routers into sinkholes.  It is
> Very Bad Idea.

I wouldn't say it is wasteful so much as it is unnecessary but the
difference is that everything is pretty much known to work as expected
with a /64 subnet.  Anything broken with a /64 is really broken and the
vendor would be expected to get right on it.  If something breaks while
using a /127, the doctor might tell you to stop sticking the spoon in
your eye.

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