[124080] in North American Network Operators' Group
Re: IP4 Space
daemon@ATHENA.MIT.EDU (Daniel Senie)
Tue Mar 23 00:40:05 2010
From: Daniel Senie <dts@senie.com>
In-Reply-To: <5F1787CD-3F1D-481A-86F7-4310C8559797@academ.com>
Date: Tue, 23 Mar 2010 00:39:26 -0400
To: NANOG list <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Mar 22, 2010, at 6:53 PM, Stan Barber wrote:
> In this case, I am talking about an IPv6<->IPv6 NAT analogue to the =
current IPv4<->IPv4 NAT that is widely used with residential Internet =
service delivery today.
>=20
> I believe that with IPv6 having much larger pool of addresses and each =
residential customer getting a large chunk of addresses will make =
IPv6<->IPv6 NAT unnecessary. I also believe that there will be IPv6 =
applications that require end-to-end communications that would be broken =
where NAT of that type used. Generally speaking, many users of the =
Internet today have not had the luxury to experience the end-to-end =
model because of the wide use of NAT.=20
End-to-end applications will face much of the same interruption issues =
in the future as today. They will face firewall equipment that inspects =
the packet stream and purposefully blocks applications that are =
potentially harmful (e.g. vectors for systems infection). While the =
address translation part of stateful inspection firewall processing may =
not be used for IPv6, all other aspects of firewall function will be as =
applicable to IPv6 packets as they are to IPv4.
>=20
> Given that these customers today don't routinely multihome today, I =
currently believe that behavior will continue. Multihoming is generally =
more complicated and expensive than just having a single connection with =
a default route and most residential customers don't have the time, =
expertise or financial support to do that. So, the rate of multihoming =
will stay about the same even though the number of potential sites that =
could multihome could increase dramatically as IPv6 takes hold.
I deal more with small businesses than residences, but I will take issue =
with the premise presented. Today there are many products, especially =
firewalls that allow "multihoming" of a sort using multiple upstream =
connections in conjunction with IPv4 and NAT. This is fairly simple, and =
can allow smaller offices, such as a company's field offices to combine =
multiple broadband connections, such as a cable modem and a DSL =
connection, to attain higher reliability and increased bandwidth.
Because these appear to be just two broadband customer modems in one =
location (whether small business or residence), you cannot easily =
determine that such combining is being done.
As this is a VERY useful, and well-used capability, it will be =
interesting to see what the vendors choose to offer in their equipment =
as IPv6 support improves.
