Subject: Re: Patrick Faltstrom message: Why SiteLocal is not what solves the problems people want to solve

From: Dan Lanciani <[email-masked]>
Date: Sat, 5 Apr 2003 15:43:17 -0500 (EST)

Mika Liljeberg <[email-masked]> wrote:

|> > Great.  Let's work on that problem now.
|> 
|> Yes, of course we should. But, I think we can not get real force behind 
|> such work before we _first_ agree Site Local is not solving this 
|> problem, and we therefore agree Site Local should go away.
|
|Forgive me for being cynical, but another way to phrase the above is
|that the intent is to deny an existing solution to people who are
|content with it in order to force them to work on a new one.

You aren't being cynical enough.  Once site-locals are gone there is
absolutely no reason to believe that there will be any work on a new
solution.  We have had years and years to work on the routing/identifier
problem and it has gone nowhere.  The new "solution" for stable internal
connections is going to be the same as the recently proposed "solution"
for multi-homing:  send more money to your ISP and they will make their
links more reliable and refrain from renumbering you as frequently.

				Dan Lanciani
				ddl@danlan.*com
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From: Måns Nilsson <[email-masked]>
Date: Mon, 07 Apr 2003 10:18:44 +0200

> links more reliable and refrain from renumbering you as frequently.

Excuse me? An ISP renumbering a client? What have you been smoking? 

Short of not giving the same DHCP lease to a home-style DSL customer, I
know of no ISP who are shoveling around their customers onto different
prefixes. Doing so would be financial suicide. 

v6 is just longer addresses, harder to remember for humans. The design and
operation of networks will not differ much from today, and any thinking ISP
would refrain from shifting prefixes around inside the same PA block,
because: 

There is no need to do it, as long as the IGP copes, and it will. 
The customer would be upset and switch providers. 
Redesigning your net just because you can is not going to earn you money. 

You are inventing problems out of thin air, I am afraid. 

-- 
Måns Nilsson            Systems Specialist
+46 70 681 7204         KTHNOC  MN1334-RIPE

We're sysadmins. To us, data is a protocol-overhead.

---

From: Tim Chown <[email-masked]>
Date: Mon, 7 Apr 2003 10:31:46 +0100

> Redesigning your net just because you can is not going to earn you money. 

The home network "site /48" is (in current speak) the same as a global
IPv4 address; in IPv6 we hope to offer a home network a real network where
previously a (usually dynamic) IPv4 address was available.
 
> You are inventing problems out of thin air, I am afraid. 

Except that an ISP with a /32 is already in address conservation mode - it
can only allocate 65K home network prefixes to customers.  If it has a
million customers, then, HD-ratio included, it will need something like
a /22 allocation.   While /32's exist, customer networks will either get 
dynamic prefixes or be allocated less than a /48.

Of course the ISP would like to be able to charge for "extras" like static
network prefixes.   Aside from privacy issues, the static /48 prefix for
home and SOHO networks is a big win for IPv6.

Tim

---

From: Måns Nilsson <[email-masked]>
Date: Tue, 08 Apr 2003 08:16:37 +0200

> dynamic prefixes or be allocated less than a /48.

I do not work at a RIR, but I'd be very astonished to find resoning against
giving such a large ISP more than one /32. I do not think it is a problem,
once we are there. 

> home and SOHO networks is a big win for IPv6.

Yes, although I do not like the "charge extra" part.

---

From: Tim Chown <[email-masked]>
Date: Tue, 8 Apr 2003 07:48:36 +0100

> giving such a large ISP more than one /32. I do not think it is a problem,

I am relaying comments from telco operators who say that /32 is not enough
if we want static prefix delegations to large numbers of customers (a typical
large DSL operator will have over 1M subscribers).   Either the telco needs
to know they can get an *aggregatable* /22 (or similar) now, else they will
have to either allocate dynamic prefixes or /64 prefixes to homes/SME's who
use DSL.

The telcos are also not clear that they have a process to apply for a /22.
Also, they would be unlikely to find many disjoint /32's efficient (after
all, we want aggregation with IPv6, don't we?).

Tim

---

From: Ronald van der Pol <[email-masked]>
Date: Tue, 8 Apr 2003 10:44:10 +0200

> all, we want aggregation with IPv6, don't we?).

So I guess we have to keep this on the agendas of the RIR meetings.

	rvdp

---

From: Brian E Carpenter <[email-masked]>
Date: Tue, 08 Apr 2003 12:03:14 +0200

> all, we want aggregation with IPv6, don't we?).

I thought that was the reason for the RIR's sparse allocation
policy at http://www.ripe.net/ripe/docs/ipv6-sparse.html

In my experience the RIR's are *acutely* aware of the concern you
mention.

   Brian

---

From: "Jeroen Massar" <[email-masked]>
Date: Tue, 8 Apr 2003 12:10:58 +0200

Måns Nilsson wrote:

> --On Tuesday, April 08, 2003 07:48:36 +0100 Tim Chown 
> <[email-masked]>
> wrote:
> 
> > if we want static prefix delegations to large numbers of customers
(a
> > typical large DSL operator will have over 1M subscribers). Either
the
> > telco needs to know they can get an *aggregatable* /22 (or similar)
now,
> > else they will have to either allocate dynamic prefixes or /64
prefixes
> > to homes/SME's who use DSL.
> > 
> I find it *very* hard to justify SL because Telco registry people are
> incompetent. ;-) 
> 
> And, I am quite convinced that RIRen allocate so that they 
> can give out larger prefixes as things grow. 

Currently the RIRs who do IPv6 (ARIN,APNIC,RIPE) give out /32's
from a /29 growing space. And ofcourse if you really need more
you should just go the RIRs and ask... If you are big enough
you can also convince them that you need it and one should then
be able to get it ofcourse. This should result in every endsite
getting a globally routable /48 from it's upstream may it be a
home site or a company. Based on the fact that more and more
people are setting up wlan one can easily figure out that there
are more than one network in those endsites thus that they
require a /48 instead of a single /64. It's also easier for
administration in most cases instead of having seperate /64's
and /48 allocations.

Greets,
 Jeroen

---

From: Tim Chown <[email-masked]>
Date: Tue, 8 Apr 2003 11:18:52 +0100

On Tue, Apr 08, 2003 at 11:29:49AM +0200, Måns Nilsson wrote:
> 
> --On Tuesday, April 08, 2003 07:48:36 +0100 Tim Chown <[email-masked]>
> wrote:
> 
> > if we want static prefix delegations to large numbers of customers (a
> > typical large DSL operator will have over 1M subscribers).   Either the
> > telco needs to know they can get an *aggregatable* /22 (or similar) now,
> > else they will have to either allocate dynamic prefixes or /64 prefixes

This has nothing to do with site locals, except that telcos need prefix
headroom to avoid having pressure to use dynamic prefixes.  The key thing
for stable addressing is that the big ISPs have clear headroom.
 
> And, I am quite convinced that RIRen allocate so that they can give out
> larger prefixes as things grow. 

Yes, they allocate with some headroom, but is it enough?

e.g.
CWJ-JPNIC-JP-20020910                              2001:0C70::/32
NTTIP-AU-20020910                                  2001:0C78::/32
InterVia-JPNIC-JP-20020916                         2001:0C80::/32
CYPRESS-NET6-JPNIC-JP-20020918                     2001:0C88::/32
from
http://www.ripe.net/ripencc/mem-services/registration/ipv6/ipv6allocs.html

So there are 8 /32's available per allocation, kind of.  In other words
an ISP can grow to a /28, which is 2^20 /48's, which is 1M /48's, but
only if you ignore practicalities of deployment (which manifest themselves
loosely in the HD-ratio - RFC3194 I think - and I recall Alain Durand
also did a corresponding I-D for prefix allocations).

We don't want to put telcos or ISPs in the position where if they look
for a plan to deploy to a million end-users (long term) they feel
"cramped" and thus use dynamic allocations or /64's...  so now they can
get multiple /28's with growth, but these would be not aggregated.

Tim

---

From: Tim Chown <[email-masked]>
Date: Tue, 8 Apr 2003 11:49:46 +0100

> an ISP can grow to a /28, which is 2^20 /48's, which is 1M /48's, but

(Actually I think that's a /29, or 500K prefixes max...)

Tim

---

From: Brian E Carpenter <[email-masked]>
Date: Wed, 09 Apr 2003 16:42:12 +0200

> (Actually I think that's a /29, or 500K prefixes max...)

Regardless, I wouldn't be shocked by a DFZ where a given ISP had multiple
/29s if it grew really big. I do agree that ISPs need to have a sense
that they can get as many of the 35 trillion /48s as they need.

   Brian

---

From: Tim Chown <[email-masked]>
Date: Thu, 10 Apr 2003 00:22:25 +0100

> that they can get as many of the 35 trillion /48s as they need.

OK, so long as the ISP's know that and don't start rolling out with 
dynamic prefixes... this would only increase clamour for site locals :(

Tim

---

From: Robert Elz <[email-masked]>
Date: Thu, 10 Apr 2003 17:29:30 +0700

Date:        Thu, 10 Apr 2003 00:22:25 +0100
    From:        Tim Chown <[email-masked]>
    Message-ID:  <[email-masked]>

  | On Wed, Apr 09, 2003 at 04:42:12PM +0200, Brian E Carpenter wrote:
  | > 
  | > Regardless, I wouldn't be shocked by a DFZ where a given ISP had multiple
  | > /29s if it grew really big. I do agree that ISPs need to have a sense
  | > that they can get as many of the 35 trillion /48s as they need.
  | 
  | OK, so long as the ISP's know that and don't start rolling out with 
  | dynamic prefixes... this would only increase clamour for site locals :(

It is irrelevant.    One of the big advantages of intermittent connections
is that they can trivially be switched to any provider.

It is highly reasonable for a site to use an ISP which specialises in
business users, but use them only during their off peak periods (at
night), and also use an ISP that specialises in home users, and use
them during their off peak periods (during the day).   Even if that
doesn't result in lowered rates, it almost certainly results in better
throughput, using the ISPs links when they're not as busy as they
are when they're most used.

But this results in 2 /48's - even if those two are stable, they're
not consistently workable, and hosts need to know which one they can
safely use right now.

That could be done using some form of scoped addressing - but SL
addresses are a better solution for that (since they're obvious),
or it can be done by only advertising the address which actually works
generally at the minute, which is what is likely to happen.

So, now all the addresses in the site switch around at least twice
a day - and there are probably periods during which neither works
(neither is advertised) so some other addresses are needed.

Nothing that comes from an ISP is, or ever will be, suitable for
use for stable addresses - not even if the ISPs were selected as a
distribution mechanism for PI addressing, there are too many issues
to deal with.

On the other hand, some address block, selected by the IETF, and
labelled as available for stable addressing purposes (just like
1918 addresses) allows a site to have confidence that the addressing
it is using for its internal communications will remain stable,
and safe to use.

What that prefix is doesn't really matter, it could be f000::/5
or E000:/4 or C000:/3 ... it could even be FEC0::/10.   Then, when
we have a block of addresses that work only locally within a site
we can give them a nice easy to remember name to use to talk about
them - maybe we call them "site local".

kre

---

From: Tim Chown <[email-masked]>
Date: Sun, 13 Apr 2003 10:24:07 +0100

On Sun, Apr 13, 2003 at 11:21:56AM +0200, Jeroen Massar wrote:
> 
> It's a /29 which the RIRs keep in reserve, that should cover
> somewhat 99% of the ISP's on this globe fortunatly.

There are still quite a few ISPs with more than 500K customers.

> I would find it very neat if an ISP requested say a /22 btw :)

The bigger mobile operators have 10M+ customers... so maybe not
that far off :)

Tim

---

From: "Jeroen Massar" <[email-masked]>
Date: Sun, 13 Apr 2003 11:21:56 +0200

It's a /29 which the RIRs keep in reserve, that should cover
somewhat 99% of the ISP's on this globe fortunatly.
The other 1% are 'big' enough and should have enough clue
and realize that they can get the space with IPv6.
Ofcourse for any instance:
'if you didn't ask the RIRs then you don't know if you can get it'

Greets,
 Jeroen

---

From: Thomas Narten <[email-masked]>
Date: Mon, 14 Apr 2003 06:51:11 -0400

Brian E Carpenter <[email-masked]> writes:

> Regardless, I wouldn't be shocked by a DFZ where a given ISP had
> multiple /29s if it grew really big. I do agree that ISPs need to
> have a sense that they can get as many of the 35 trillion /48s as
> they need.

Or a single /28, or something even shorter.

See, for isntance, "RIPE 261 Document: IPv6 Address Space
Management". Implementation of this algorithm eliminates even the
current /29 limitation.

http://www.ripe.net/ripe/docs/ipv6-sparse.html

Thomas