[124072] in North American Network Operators' Group
Re: IP4 Space
daemon@ATHENA.MIT.EDU (Stan Barber)
Mon Mar 22 18:54:08 2010
From: Stan Barber <sob@academ.com>
In-Reply-To: <75cb24521003181820k4d307d3eid7e25508c69ce82c@mail.gmail.com>
Date: Mon, 22 Mar 2010 17:53:01 -0500
To: Christopher Morrow <morrowc.lists@gmail.com>
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
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.
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
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.
Now, there are clearly lots of specifics here that may change over time =
concerning what the minimum prefix length for IPv6 advertisements might =
be acceptable in the DFZ (some want that to be /32, other are ok with =
something longer). I don't know how that will change over time. I also =
think that that peering will continue to increase and that the prefix =
lengths that peers will exchange with each other are and will continue =
to be less constrained by the conventions of the DFZ since the whole =
point of peering is to be mutually beneficial to those two peers and =
their customers. But, that being said, I don't think residential =
customers will routinely do native IPv6 peering either. I think =
IP6-in-IPv4 tunneling is and will continue to be popular and that =
already makes for some interesting IPv6 routing concerns.=20
Hope that clarifies my comment for you. Obviously, they are my opinions, =
not facts. The future will determine if I was seeing clearly or was =
mistaken in how these things might unfold. However, I think a discourse =
about these possibilities is helpful in driving consensus and that's one =
of the valuable things about mailing lists like this.
On Mar 18, 2010, at 8:20 PM, Christopher Morrow wrote:
> On Thu, Mar 18, 2010 at 7:36 PM, Stan Barber <sob@academ.com> wrote:
>> Ok. Let's get back to some basics to be sure we are talking about the =
same things.
>>=20
>> First, do you believe that a residential customer of an ISP will get =
an IPv6 /56 assigned for use in their home? Do
>> you believe that residential customer will often choose to multihome =
using that prefix? Do you believe that on an
>> Internet that has its primary layer 3 protocol is IPv6 that a =
residential customer will still desire to do NAT for reaching
>=20
> how are nat and ipv6 and multihoming related here? (also 'that has a
> primary layer 3 protocol as ipv6' ... that's a LONG ways off)
>=20
> -chris
>=20
>> IPv6 destinations?
>>=20
>> I am looking forward to your response.
>>=20
>>=20
>>=20
>>=20
>> On Mar 18, 2010, at 2:25 PM, William Herrin wrote:
>>=20
>>>> On Mar 5, 2010, at 7:24 AM, William Herrin wrote:
>>>>> Joel made a remarkable assertion
>>>>> that non-aggregable assignments to end users, the ones still =
needed
>>>>> for multihoming, would go down under IPv6. I wondered about his
>>>>> reasoning. Stan then offered the surprising clarification that a
>>>>> reduction in the use of NAT would naturally result in a reduction =
of
>>>>> multihoming.
>>>=20
>>> On Thu, Mar 18, 2010 at 11:07 AM, Stan Barber <sob@academ.com> =
wrote:
>>>> I was not trying to say there would be a reduction in multihoming. =
I was
>>>> trying to say that the rate of increase in non-NATed single-homing
>>>> would increase faster than multihoming. I guess I was not very =
clear.
>>>=20
>>>=20
>>> Hi Stan,
>>>=20
>>> Your logic still escapes me. Network-wise there's not a lot of
>>> difference between a single-homed IPv4 /32 and a single-homed IPv6
>>> /56. Host-wise there may be a difference but why would you expect =
that
>>> to impact networks?
>>>=20
>>> Regards,
>>> Bill Herrin
>>>=20
>>>=20
>>>=20
>>> --
>>> William D. Herrin ................ herrin@dirtside.com =
bill@herrin.us
>>> 3005 Crane Dr. ...................... Web: <http://bill.herrin.us/>
>>> Falls Church, VA 22042-3004
>>=20
>>=20
>>=20
