[AusNOG] IPv6

[Mark Andrews]

In message <8678eef1448b461db0b9abd67b105095 at mail2.lenevez.net.au>, Anthony Bor
tolotto writes:
>
> The person who turned it on in the first place would need to know what 
> IPv6 is. It is not turned on by default on most customer CPEs because not 
> every network or device supports it and the manufacturer doesnt want 
> returned equipment because it doesnt work when they bought it at Harvey 
> Norman because the ISP hasnt deployed it correctly.

And the ISP doesn't have to support it before the CPE attempts to
configure it.  The CPE attempts to bring IPv6 up in parallel with
IPv4.  If IPv6 does not come up because there is no DHCPv6 server
or no 6RD option in the DHCPv4 response etc. then no harm, no foul.
The lan(s) will remain IPv4 only.  The CPE will just wait for IPv6
to become available the same way as it will wait for a DHCPv4 server
to become available.

This is like the CPE not enabling DHCPv4 by default because the ISP
may not be running DHCPv4.

6in4 tunnels and 6to4 need to be manually configured.  Listening
for RA's, requesting 6rd configuration, attempting to bring up IPv6
over PPP can all be done automatically without harm.  You don't
configure IPv6 the lan until you have gotten addresses from the ISP
or you have other explict configuration.  You can even run 6rd in
parallel with IPv6 native so there is no need to do sudden transitions
when the ISP goes from 6rd to IPv4 native.

If IPv6 gets configured and is broken then the clients will fallback
to IPv4.  That is a RFC 1123 requirement which predates IPv6.

> Then you move to the customer that would potentially want to create a 
> port forward to a device using an IPv6 address which obviously isnt going 
> to work so it is easier for them to not use it.

Port "forwarding" is just opening a firewall hole.
 
> Less than 10% of our customers utilise our IPv6 deployment even though we 
> have it turned on by default and manage the stack at the same priority of 
> IPv4.

But they have it available.  You as a ISP are no longer the stumbling block.
 
> I welcome the day it is on by default but its the humans that is the 
> problem. You could say that about IT in general though
-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka at isc.org