[181811] in North American Network Operators' Group
Re: Dual stack IPv6 for IPv4 depletion
daemon@ATHENA.MIT.EDU (Mel Beckman)
Sun Jul 5 11:52:40 2015
X-Original-To: nanog@nanog.org
From: Mel Beckman <mel@beckman.org>
To: Josh Moore <jmoore@atcnetworks.net>
Date: Sun, 5 Jul 2015 15:52:36 +0000
In-Reply-To: <6CC42ADB-2942-4466-87C9-E246EB08CBE1@atcnetworks.net>
Cc: "nanog@nanog.org" <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
Dual-stack doesn't require public IPv4 addresses. Since IPv4 is in short su=
pply, providers must still do what they can to conserve them. This means NA=
T, with appropriate management to not overload any one IP, or CGN if you wa=
nt to keep public IPv4 (but no longer unique ones) on CPE. Not every custom=
er needs direct IPv4 connectivity without NAT; those that do must pay for i=
t. If those who have it aren't willing to pay, they must give up their publ=
ic IPv4 address.=20
That is the most efficient direct IPv4 provisioning concept we have today. =
Given the history of IPv6 adoption, it's clear that people won't move until=
they experience pain sticking with IPv4.=20
"On demand" IPv4 isn't currently being done anywhere AFAIK, and since we're=
abandoning IPv4 it's not likely anyone has that on their priority list. It=
's not a good policy to go out of your way to make IPv4 users comfortable. =
IPv4 is going to go away, and the sooner customers get that and go to IPv6,=
the sooner the pain will stop :)
-mel beckman
> On Jul 4, 2015, at 6:02 PM, Josh Moore <jmoore@atcnetworks.net> wrote:
>=20
> Traditional dual stack deployments implement both IPv4 and IPv6 to the CP=
E.
> Consider the following:
>=20
> An ISP is at 90% IPv4 utilization and would like to deploy dual stack wit=
h the purpose of allowing their subscriber base to continue to grow regardl=
ess of the depletion of the IPv4 space. Current dual stack best practices s=
eem to recommend deploying BOTH IPv4 and IPv6 to every CPE. If this is the =
case, and BOTH are still required, then how does IPv6 help with the v4 addr=
ess depletion crisis? Many sites and services would still need legacy IPv4 =
compatibility. Sure, CGN technology may be a solution but what about applic=
ations that need direct IPv4 connectivity without NAT? It seems that there =
should be a mechanism to enable on-demand and efficient IPv4 address consum=
ption ONLY when needed. My question is this: What, if any, solutions like t=
his exist? If no solution exists then what is the next best thing? What wou=
ld the overall IPv6 migration strategy and goal be?
>=20
> Sorry for the length of this email but these are legitimate concerns and =
while I understand the need for IPv6 and the importance of getting there; I=
don't understand exactly HOW that can be done considering the immediate is=
sue: IPv4 depletion.
>=20
>=20
> Thanks
>=20
> Joshua Moore
> Network Engineer
> ATC Broadband
> 912.632.3161
