Requirements for IPv6 Firewalls

George Herbert george.herbert at
Thu Apr 17 20:45:59 UTC 2014

On Thu, Apr 17, 2014 at 11:32 AM, Eugeniu Patrascu <eugen at>wrote:

> ...
> It's a bigger risk to think that NAT somehow magically protects you against
> stuff on the Internet.
> Also, if your problem is that someone can screw up firewalls rules, then
> you have bigger issue in your organization than IPv6.

> There's a fair argument to be made which says that kind of NAT is
> > unhealthy. If its proponents are correct, they'll win that argument
> > later on with NAT-incompatible technology that enterprises want. After
> > all, enterprise security folk didn't want the Internet in the
> > corporate network at all, but having a web browser on every desk is
> > just too darn useful. Where they won't win that argument is in the
> > stretch of maximum risk for the enterprise security folk.
> >
> >
> Any technology has associated risks, it's a matter of how you
> reduce/mitigate them.
> This paranoia thingie about IPv6 is getting a bit old.
> Just because you don't (seem to) understand how it works, it doesn't mean
> no one else should use it.

You are missing the point.

Granted, anyone who is IPv6 aware doing a green-field enterprise firewall
design today should probably choose another way than NAT.

What you are failing is that "redesign firewall rules and approach from
scratch along with the IPv6 implementation" usually is not the chosen path,
versus "re-implement the same v4 firewall rules and technologies in IPv6
for the IPv6 implementation", because all the IPv6 aware net admins are
having too much to do dealing with all the other conversion issues, vendor
readiness all across the stack, etc.

Variations on this theme are part of why it's 2014 and IPv6 hasn't already
taken over the world.  The more rabid IPv6 proponents have in fact shot the
transition in the legs repeatedly, and those of us who have been on the
front lines would like you all to please shut up and get out of the way so
we can actually finish effecting v6 deployment and move on to mopping up
things like NAT later.

This is why listening to operators is important.

-george william herbert
george.herbert at

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