[CGA-EXT] One more bit for hash information in CGAs? ( was [Fwd: [BEHAVE] Modified EUI-64 format]

marcelo bagnulo braun <marcelo@it.uc3m.es> Mon, 06 July 2009 18:58 UTC

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Date: Mon, 06 Jul 2009 20:58:17 +0200
From: marcelo bagnulo braun <marcelo@it.uc3m.es>
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Cc: Dave Thaler <dthaler@windows.microsoft.com>
Subject: [CGA-EXT] One more bit for hash information in CGAs? ( was [Fwd: [BEHAVE] Modified EUI-64 format]
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There is an ongoing discussion in BEHAVE ml, where it seems that we 
could use the "g" bit in order to include hash information...
considering that the hash length is one of the key limitations of CGAs, 
we may consider updating 3972 to use this bit...
comments?

I attach the extract of the thread below...

-------- Mensaje original --------
Asunto: 	[BEHAVE] Modified EUI-64 format
Fecha: 	Thu, 2 Jul 2009 04:06:21 +0000
De: 	Dave Thaler <dthaler@windows.microsoft.com>
Para: 	Xing Li <xing@cernet.edu.cn>
CC: 	Behave WG <behave@ietf.org>



Similarly, with privacy addresses referred to in the draft quote
at top, RFC 3041 section 3.2.1 point 3 forces the randomized
interface identifier to adhere to this requirement, so that it's
a 63-bit random number, not a 64-bit random number.  And with
CGAs, RFC 3972 section 4 point 6 similarly forces a generated
interface identifier to adhere to this requirement. (As an aside,
it also reserves the "g" bit which is actually unnecessary
since it's not IEEE EUI-64-derived.  RFC 4291 only discusses
the "g" bit for addresses derived from IEEE EUI-64's, which
is why RFC 3041 and a translation format can still use that bit).