Réf. : Re: Réf. : Re: R if._:_Re:_IPv6_Linklocal_address_and_IPSec_bug

From: <Sebastien.Josset(at)space.alcatel.fr>
Date: Mon Sep 22 2003 - 03:37:00 EDT

Hi Peter,

According to the book I use as reference (IPv6 theory and practic: O'Reilly, Gizele Cizault),
An IPv6 multicast address is: ff.flag(4bits).scope(4bits).group id (112 bits) And scope values can be:

0: reserved
1: Node local scope
2: link local scope

3 subnet scope

5: site scope
8: Organization-local scope
E: global scope
F: reserved

The idea is: 8 is a larger scope that 6 that is a larger scope that 4 etc. It only differs for 3 and 4. Ok, I agree that only references should be RFCs...
What I want to say is 'link local' (2) addresses need a patch in order to be deciphered by openBSD IPSec.
I've tested with (3) that does work. For the others I don't known.

Hope it helps,

best regards,

Sébastien Josset

Peter Curran <peter@closeconsultants.com> on 20/09/2003 10:34:15

Pour : Sebastien.Josset@space.alcatel.fr cc : ipv6@openbsd.org (ccc : Sebastien Josset/ALCATEL-SPACE) Objet : Re: Réf. : Re: R if._:_Re:_IPv6_Linklocal_address_and_IPSec_bug
> Please note that ff13::1234:5678 are multicast IPv6 address with network
> scope
> ('3') and works fine

Where does scope '3' come from?

According to RFC3513....
scop is a 4-bit multicast scope value used to limit the scope

         of the multicast group. The values are:

            0  reserved
            1  interface-local scope
            2  link-local scope
            3  reserved
            4  admin-local scope
            5  site-local scope
            6  (unassigned)
            7  (unassigned)
            8  organization-local scope
            9  (unassigned)
            A  (unassigned)
            B  (unassigned)
            C  (unassigned)
            D  (unassigned)
            E  global scope
            F  reserved

Cheers

Peter

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Received on Mon Sep 22 04:09:47 2003