RE: Unreachability detection at tunnels servers WAS: RE: Comments onzeroconf draft

[Soohong Daniel Park <soohong.park@samsung.com>]

> MUST Ipv6-in-Ipv4 tunnel servers, as routers, support NUD-like 
> mechanisms that enables
> them to send ICMP destination unreachable messages back to origin ?

(Sorry if I am missing anything on this thread because I didn't
fully follow up that so far.)

When I saw this draft, below sentence was to cover the above concern.
 
6.8. Tunnel End-Point Reachability Detection

   The tunnel protocol must allow for means for one tunnel end-point to
   verify the reachability of other tunnel end-points towards which it
   intends to send packets.

   The unicast neighbor reachability discovery functions provided by
   IPv6 Neighbor Discovery ([13]), i.e., unicast NS/NA exchanges, should
   be supported on the tunnel link.


NUD-like sounds good for me, however ICMP message exchange is not
only available to verity a reachability between two endpoints. So don't limit 
this goal to the ICMP. 

When I implemented IPv6-over-IPv4 tunnel using DHCP, I used TCP/UDP
port assigned by admin in advance between them, and it works well.


Hope this helps.


     Daniel (Soohong Daniel Park)
     Mobile Platform Lab. Samsung Electronics.