From: William Herrin <bill@herrin.us>
Subject: Re: [RRG] Long term clean-slate only for the RRG?
To: HeinerHummel@aol.com
Cc: jnc@mercury.lcs.mit.edu, rrg@psg.com
Date: Thursday, July 3, 2008, 3:45 PM
On Thu, Jul 3, 2008 at 3:49 AM,
<HeinerHummel@aol.com> wrote:
In einer eMail vom 02.07.2008 23:43:24
Westeuropäische Normalzeit schreibt
bill@herrin.us:
Layer-3 addresses presently describe two
characteristics of the
endpoint: its network location and its identity.
In a clean slate
environment, it is not obvious to me that
path-selection need know
anything about the identity part; it need only
know about one of the
network locations.
Right. I'd call it "learning from the
postman".A letter isn't checked at the
ingress postal office whether it is deliverable or not
(whether the receiver
has or has not moved to some other place). Instead it
is forwarded to the
egress postal office without such checking. No attempt
is made neither as to
inform, world-wide, any postal office when someone
moves to another
place. Every year many new residential areas are going
to be developed, but
no postman has ever complained about an (increasing)
scalability problem.
Heiner,
I'm not sure that speaks to the question. Let me borrow
your analogy:
Line 1: William Herrin
Line 2: 3005 Crane Drive
Line 3: Falls Church, VA 22042
Line 4: United States
Your point is that a post office in Dublin need not know
about 3005
Crane Drive. It need only get the mail to the US. The first
post
office in the US need not know about Crane Drive either; it
need only
get the mail to the post office for 22042. The post office
for 22042
does, however, need to know how to get to 3005 Crane Drive.
While that's undoubtedly true, all of lines 2 through 4
are used for
path selection at various stages of the letter's trip.
As Noel said,
they are inherently inseparable from the path selection
process.. I
could not, for example, tell the post office in Dublin to
deliver a
letter to "3005 Crane Drive, United States" or
"Falls Church VA,
United States." It wouldn't reach me.
-MY- point was that Line 1 need not be there at all. It is
an
identifier which serves no role in the routing. If you get
line 1
wrong or leave it off entirely your letter will still get
to me.
Line 1 is valuable for other purposes. I generally
round-file letters
addressed to "Current Resident" and I
wouldn't want to accidentally
open someone else's mail. However, there is no inherent
reason that
"William Herrin" must be a part of the address.
It would be just as
functional if I found it on a second envelope enclosed in
the first.
This is important, because as it turns out, letters address
to:
Line 1: William Herrin
Line 2: 6857 Lafayette Park Drive
Line 3: Annandale, VA 22003
Line 4: United States
will ALSO get to me, albeit a little more slowly. The
person with my
identity is reachable at multiple locations each of which
can be
described in a manner close enough to a hierarchy to be
efficient.
Regards,
Bill Herrin
--
William D. Herrin ................ herrin@dirtside.com
bill@herrin.us
3005 Crane Dr. ...................... Web:
<http://bill.herrin.us/>
Falls Church, VA 22042-3004
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