[128024] in North American Network Operators' Group
Re: Addressing plan exercise for our IPv6 course
daemon@ATHENA.MIT.EDU (Owen DeLong)
Fri Jul 23 01:24:39 2010
From: Owen DeLong <owen@delong.com>
In-Reply-To: <4C491FC2.5040308@ttec.com>
Date: Thu, 22 Jul 2010 22:23:17 -0700
To: Joe Maimon <jmaimon@ttec.com>
Cc: nanog list <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Jul 22, 2010, at 9:51 PM, Joe Maimon wrote:
>=20
>=20
> Mark Smith wrote:
>> On Fri, 23 Jul 2010 00:33:45 +0100
>> Matthew Walster<matthew@walster.org> wrote:
>>=20
>>> On 22 July 2010 14:11, Alex Band<alexb@ripe.net> wrote:
>>>> There are more options, but these two are the most convenient =
weighing all
>>>> the up and downsides. Does anyone disagree?
>>>=20
>>> I never saw the point of assigning a /48 to a DSL customer. Surely =
the
>>> better idea would be to assign your bog standard residential DSL
>>> customer a /64 and assign them a /56 or /48 if they request it, =
routed
>>> to an IP of their choosing.
>>>=20
>>=20
>> I estimate that an addressing request will cost the ISP at least 15
>> minutes of time to process. When a minimum allocation of a /32 =
contains
>> 16 777 216 /56s, do you really need to create that artificial
>> addressing cost, eventually passed onto the customer?
>=20
> Funny how so much concern is given to eliminating the possibility of =
end users returning for more space, yet for ISP's we have no real =
concern with what will happen when they near depletion of their /32 what =
with /48s to some thousands customers, aggregation, churn, what have =
you.
>=20
There's no need to give it a lot of concern because that process is =
pretty well understood and not particularly different from the current =
process in IPv4.
When an ISP runs out, they apply for more from either their upstream, =
or, their RIR. Just that simple.
> The effort and cost of that on the organization is hard to predict, =
especially as how it may vary from size to size, organization to =
organization. Furthermore, everyone else pays with a DFZ slot.
>=20
Yeah, but, the number of DFZ slots consumed by this in IPv6 will be so =
much smaller than IPv4 that I really find it hard to take this argument =
seriously.
Additionally, it's not necessarily true due to allocation by bisection.
> /48 per customer gives the customer as many potential subnets as you =
have potential customers.
>=20
You say that like it is a bad thing.
>>=20
>> With more address space than we need, the value we get is addressing
>> convenience (just like we've had in Ethernet addressing since 1982).
>> There is no need to make IPv6 addressing artificially precious and as
>> costly as IPv4 addressing is.
>=20
> A balance should be struck and for that to happen, weight must be =
given to both sides.
>=20
And it has. /32 is merely the default minimum allocation to an ISP. =
Larger blocks
can be given, and, now that the RIRs are allocating by bisection, it =
should even
be possible in most cases for that additional space to be an expansion =
of the
existing allocation without changing the number of prefixes.
e.g. 2001:db8::/32 could be expanded to 2001:db8::/28
16 times as much address space, same number of DFZ slots.
Owen
