Subject: RE: [rfc2462bis] summary and proposal about the M/O flags

From: "Christian Huitema" <[email-masked]>
Date: Mon, 24 May 2004 23:20:39 -0700

>   Note that it is possible that there is no router on the link in this
>   sense but is a node that has the ability to forward packets.  In
>   this case, hosts must be manually configured about the forwarding
>   node's address to be able to send packets off-link, since sending
>   router advertisements is the only mechanism to configure the default
>   router's address automatically.

You are describing the "multi-link subnet" or "ND-proxy" scenario. May I suggest that we leave this to a specialized multi-link or ND-proxy RFC? 

-- Christian Huitema

--------------------------------------------------------------------
IETF IPv6 working group mailing list
[email-masked]
Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6
--------------------------------------------------------------------

---

From: JINMEI Tatuya / 神明達哉<[email-masked]>
Date: Tue, 25 May 2004 18:16:05 +0900

>>>>> On Mon, 24 May 2004 23:20:39 -0700, 
>>>>> "Christian Huitema" <[email-masked]> said:

> You are describing the "multi-link subnet" or "ND-proxy"
> scenario. May I suggest that we leave this to a specialized
> multi-link or ND-proxy RFC? 

I don't mind to leave describing the issue to some other document(s),
but let me try to clarify one thing: I don't think this is specific to
the "multi-link subnet" or "ND-proxy" scenarios.  The problematic case
(if we call it a problem) can happen due to simple misconfiguration.

I'm even not sure if the "multi-link subnet" or "ND-proxy" scenarios
is ever related to the point I described...as far as I know, the host
can still see router advertisements from a "router" in the sense of
RFC2462 (or rfc2462bis), which is just located in a different link
from the host's link.  On the other hand, I was talking about the case
where the host does not see any router advertisements, whether via the
directly attached link or from a separate link via a "proxy" while
there is still a node that can forward any kinds of IPv6 packets.

					JINMEI, Tatuya
					Communication Platform Lab.
					Corporate R&D Center, Toshiba Corp.
					[email-masked]

---

From: Tim Chown <[email-masked]>
Date: Wed, 26 May 2004 22:53:16 +0100

> there is still a node that can forward any kinds of IPv6 packets.

[First, I think all your proposed changes are very good!]

The implication of the dhc discussion was that if the only way for a node
to learn its/a default router should be via receipt of an RA, and not via any
stateful protocol.   

The same discussion also suggested the same single solution for discovery
of on-link prefixes (i.e. these should be available only via RAs and not
via stateful protocols).

These have implications for your forwarding node on a link with no RA.

This issue needs to be clarified/documented somewhere.  I'm not sure the ND 
proxy document is that place...

Tim