Subject: (ngtrans) Question about Neighbor Discovery over tunnels

From: Noelia Garcia <[email-masked]>
Date: Tue, 23 May 2000 16:26:56 +0200

I have developed an IPv6 stack for a router; to connect it to the 6bone  I
am implementing  tunnels  Ipv6 over Ipv4 according to the Internet Draft "
Transition Mechanisms for Ipv6 Hosts and Routers", but I have the next
problem: 
When the Ipv4 connectivity in the tunnel fails (because of an external
cause), the router does not realize of that , continues routing packests
through  the tunnel and these packets are lost. If I implement Neighbor
Unreachability Detection for the link local address of the end side of
tunnel, I could desactive this tunnel when no answer is received, and these
packets could use  an alternative path to reach the destination; however I
do not receive response to  the probe packets used by NUD I send . Therefore
I do not know how to detect that the IPv4 conectivity of one tunnel has
failed ( to desactivate it and use an alternative one) and how to detect
that is "up" again to activate it.
Could someone helping me???
Thanks.
Noelia.

---

From: JINMEI Tatuya / 神明達哉<[email-masked]>
Date: Wed, 24 May 2000 13:36:55 +0900

>>>>> On Tue, 23 May 2000 16:26:56 +0200, 
>>>>> Noelia Garcia <[email-masked]> said:

> Could someone helping me???

How about just running an IPv6 routing protocol such as RIPng or BGP4+
on the tunnel?

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

p.s. KAME's implementation (see http://www.kame.net) supports NUD on
p2p links, so you can expect routers based on the KAME's
implementation to react to your solicitation.