Subject: RE: draft-ipngwg-default-addr-select-00.txt

From: [email-masked]
Date: Fri, 29 Oct 1999 11:12:04 -0400

Steve,

So  a node should know that two or more interfaces are on the same link?
I am not sure how you had in mind that this would be done. Could you
elaborate on this?

Thanks
Alex

Steve Deering <[email-masked]> on 10/29/99 10:27:42 AM

Sent by:  Steve Deering <[email-masked]>

To:   Richard Draves <[email-masked]>
cc:   [email-masked] (Alex Conta/US/3Com)
Subject:  RE: draft-ipngwg-default-addr-select-00.txt

Sorry for not having the cycles to engage in this address-selection
discussion at the moment, but here's a nit that caught my eye:
At 12:00 AM -0700 10/29/99, Richard Draves wrote:
>...link-local destinations can't be forwarded between interfaces,...
Link-locals *can* be forwarded between interfaces connected to the same
link.
Steve
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---

From: Steve Deering <[email-masked]>
Date: Fri, 29 Oct 1999 08:35:21 -0700

>I am not sure how you had in mind that this would be done. Could you

Alex,

Today, it could be known only via manual configuration.  We could think
about specifying a protocol for auto-detecting that situation (e.g., send
a link-local multicast out each interface and see if it arrives on any
othe interface), but given the rarity of the situation, I don't think
that's an urgent work item.

Steve

---

From: Steve Deering <[email-masked]>
Date: Fri, 29 Oct 1999 09:03:57 -0700

>that's an urgent work item.

To follow up my own message, the reason I pointed out this technicality
(that a node may have more than one interface to the same link) is to
suggest that it would be good if implementations didn't wire in the
assumption that 1 link = 1 interface.  For example, you will probably
have some sort of data structure for an "attached site" that lists
or points to the set of interfaces attached to that site, and it
would be a good idea to have an analogous data structure for an
"attached link" that lists the set of interfaces attached to that
link; of course that list will by default contain a single interface
and will very rarely contain more than one interface.

Steve