Subject: Overlapping namespaces

From: Iljitsch van Beijnum <[email-masked]>
Date: Wed, 8 Jan 2003 15:52:41 +0100 (CET)

If we go down the identifier/locator separation path, what would be
preferable:

1. Use an explicit namespace identifier
2. Accept overlapping namespaces

(For instance, without further information the identifier 0x782e7476
could be interpreted as either "x.tv", a valid hostname, or
"120.46.116.118", a valid IPv4 address.)

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From: Brian E Carpenter <[email-masked]>
Date: Thu, 09 Jan 2003 15:12:05 +0100

Why would we have to make that choice, rather than simply picking a
namespace?

I would recommend a subset of the IPv6 address space as the namespace,
with the current PA space as the locator space.

(Two IPv6 addresses in one packet, one as a locator and one as
an identifier. Why not?)

   Brian

P.S. This is a solutions discussion. Where's the requirements draft at?

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From: RJ Atkinson <[email-masked]>
Date: Thu, 9 Jan 2003 09:30:07 -0500

On Thursday, Jan 9, 2003, at 09:12 America/Montreal, Brian E Carpenter 
> (Two IPv6 addresses in one packet, one as a locator and one as

	The above is very substantially close to what the Mobile-IPv6 stuff
is doing, at least in the documents I skimmed last Fall.

Ran

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From: Iljitsch van Beijnum <[email-masked]>
Date: Thu, 9 Jan 2003 17:19:14 +0100 (CET)

> Why would we have to make that choice, rather than simply picking a

Maybe a better one will be invented in the future. Also, something like
HIP looks interesting and would be easier to support this way.

> with the current PA space as the locator space.

Hm, then those could also be used as the globally unique site local
addresses the ipv6 wg (or was it one of the others?) is looking for.
And it could lead towards Michel's MHAP.

> (Two IPv6 addresses in one packet, one as a locator and one as

Because IPv6 packets have too much overhead as it is. With an additional
32 bytes a TCP ACK would be 92 bytes, more than twice what it is in
IPv4. Also, why would the identifier have to be in each packet?
Exchanging them at the start of a session should be enough.

> P.S. This is a solutions discussion. Where's the requirements draft at?

There was essentially zero progress for the requirements draft in 2002.