[135067] in North American Network Operators' Group
Re: Is NAT can provide some kind of protection?
daemon@ATHENA.MIT.EDU (Owen DeLong)
Sun Jan 16 00:45:57 2011
From: Owen DeLong <owen@delong.com>
In-Reply-To: <20110116143312.131f9c67@opy.nosense.org>
Date: Sat, 15 Jan 2011 21:40:41 -0800
To: Mark Smith <nanog@85d5b20a518b8f6864949bd940457dc124746ddc.nosense.org>
Cc: NANOG list <nanog@nanog.org>, Brandon Ross <bross@pobox.com>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Jan 15, 2011, at 8:03 PM, Mark Smith wrote:
> On Sat, 15 Jan 2011 18:21:52 -0600
> "Frank Bulk" <frnkblk@iname.com> wrote:
>=20
>> I hope the engineers in the organization will just tell their =
marketing folk
>> that it's not possible to hand out just one IPv6 address. "Our =
hardware
>> doesn't support it."
>>=20
>> I think there's still room for ISPs to charge $10/month for a static =
prefix,
>> though. And that's technically possible.
>>=20
>=20
> I think it is important to define what "static" means. My definition =
is
> that no matter where the customer's network attachment point moves to,
> the customer retains the same addressing while they have a continued
> commercial relationship with the SP - in effect PI address space =
within
> the SPs network. There is a fairly significant cost to preserving =
that,
> a guaranteed route table slot. This is typically a business product
> offering.
>=20
Uh, yeah, I think most SPs will only provide that as long as the =
customer
is attached at the same POP or possibly in the same Region, whatever
their aggregation zone happens to be.
If you're going to have the customer tying up a slot in the routing =
table,
there's not much benefit (from an SP perspective) vs. having them go
get an AS and a PI Prefix.
> The only other alternative people seem to think there is is dynamic,
> where every time the customer reconnects they may get different
> addressing. This is the typical residential product offering.
>=20
Well, there's static as long as the customer stays where they are or
moves within the same access aggregation facility. That's relatively
easy for the provider and solves 99.99% of the residential customer's
problems with dynamic.
> I think there is a useful middle point of "stable" addressing, where =
as
> long as their point of attachment (or point of service delivery - i.e.
> their home) doesn't change, a customer would continue to get the
> same addressing. This idea wasn't as useful or as applicable in IPv4,
Frankly, that's what I thought you meant by "static" at first.
> but would be quite beneficial in IPv6 when DHPCv6-PD is being used. It
> wouldn't be an assured address assignment, however the SP would
> endeavour to try to ensure the addressing stays stable over quite long
> periods of time. It's common enough for LNS/BRASes to do this anyway =
if
Hmmm... Now your going away from your definition of "stable" to what I
would call "semi-sticky dynamic addressing". It's a darker shade of gray
than "stable", but, still reasonably usable.
> the customer's connection lands on the same one. The trick is to =
expand
> this stability over the group of all LNS/BRASes that customers can
> attach to when they reconnect, such that is a SP designed behaviour,
> rather than an implementation behaviour of each individual LNS/BRAS.
>=20
You're making a rather large assumption here. Namely that all the world
is DSL.
Owen
