Subject: RE: to be draft-ohta-multi6-8plus8-00.txt

From: [email-masked] (Noel Chiappa)
Date: Sat, 24 Jan 2004 08:22:27 -0500 (EST)

> From: "marcelo bagnulo" <[email-masked]>

    >> How can you make IDs survive ISP changes?

    > Well, this is a plus but it is not the problem that we are trying to
    > solve here, right?
    > .. we could have a multihoming solution that don't provide this

Not that I'm arguing *against* doing this, but I'm just curious as to what the
perceived need is (for having the identity not change if you stop buying
service from your old ISP and switch to a new one). Let me devil's advocate
for a second...

I mean, when you change ISP's, if you expect any incoming connections (i.e. if
you're in a directory database with some fixed name) then you have to go into
the database(s) (DNE, etc) and update it to show your new location. So what's
the issue if you have to change the identity field too?

I guess the answer is two-fold - and both parts assume that when you change
your location, you don't need to do anything manual to get the new location
into the computer which moved.

First, iff you don't expect any incoming connections, then if your identity
stays the same there is nothing to change in the moved computer. (If your
identity changed, you'd have to get that into the computer after it moved. Not
impossible, but an extra problem.)

If you do expect incoming connections, you still don't have to change anything
in the computer, just the DNS/etc record(s) - and if one day we get secure DNS
with secure updates, presumably the moved computer could update the DNS
automatically.

Did I miss anything?

	Noel

---

From: Masataka Ohta <[email-masked]>
Date: Sun, 25 Jan 2004 08:28:51 +0900

Noel;

> service from your old ISP and switch to a new one).

Please be aware that we buy service from multiple ISPs, some of which
may change.

> the issue if you have to change the identity field too?

With ISP independent ID, you don't have to change ID hardcoded in
some file such as domain_name<->ID mapping.

> with secure updates, presumably the moved computer could update the DNS

It is a classic misunderstanding on possibility of automatic
renumbering ignoring DNS glue, which is too subtle to
understand without much expertise in DNS.

							Masataka Ohta

---

From: "marcelo bagnulo" <[email-masked]>
Date: Sun, 25 Jan 2004 12:29:24 +0100

Hi Noel,

Well, i think that providing stable ids (independent of the provider) is a
good approach not really becuase today things may be simpler but because we
can benefit from it in the future.

I mean, i guess we agree that renmbering when changing ISP is a must and so
obtaining a simple and cheap renumbering process is good.

Probably locators will be hardcoded in less places than today, so they will
be simpler to renumber and IDs will be hardcoded in some of the places that
ip are used today and perhaps in many others, since they will be used for
recognizing endpoints in apps and filters, acls and so on

So renumbering locators maybe simpler than renumbering IPs today, but
renumbering IDs may be quite complex since it may require lots of manual
configuration

IMHO, stable ids are good

Does this makes sense to you?

Regards, marcelo

> Not that I'm arguing *against* doing this, but I'm just curious
> as to what the perceived need is (for having the
> identity not change if you stop buying
> service from your old ISP and switch to a new one). Let me
> devil's advocate for a second...
>