Issues of DHCPv4 over v4-in-v6 tunnel [RE: WGLC ent-analysis-03: DSTM]

[Pekka Savola <pekkas@netcore.fi>]

I've changed the subject line, as a placeholder for future 
discussions..

On Mon, 22 Aug 2005, Christian Huitema wrote:
> >    While DHCPv4 may or may not require minor tweaks (e.g., relating to
> >    link-layer adaptation),
> >
> > => using DHCPv4 over a tunnel is *not* a minor tweak.
[...]
> The design becomes a little bit harder if we cannot use multicast,
> either because it is not reliable or because it creates too much
> overhead. But there are solutions -- certainly simpler than doing IPv4
> over ATM.

Well, we could have the same assumptions as DHCPv6 -- either 
multicast, or relays (certainly not just multicast).

But can't we just make the assumptions:
 1) the tunnel is point-to-point, so neither side performs ARP (so we 
may not need to define ARP), just throws the packets over.

 2) DHCPv4 server must reside at the tunnel end-point.

Isn't it then pretty much irrelevant which L2 addresses are used by 
the client (in the payload) as long as they're a good identifier in 
the DHCP server's database?

Note that I don't see modifications to DHCPv4 client or server 
software as a problem (but hopefully the changes should be minimized), 
because those sites wanting to deploy v6 dominant networks require 
lots of software updates in any case.

Maybe this discussion should go over at DHC WG, though.

--
Pekka Savola                 "You each name yourselves king, yet the
Netcore Oy                    kingdom bleeds."
Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings