Subject: Server Unicast issue for DHCPv6 -19 Draft

From: "Bernie Volz (EUD)" <[email-masked]>
Date: Tue, 17 Jul 2001 10:28:46 -0500

Hi:

One more issue for the -19 draft ... for the "Server Unicast Option" (Section 18.10),
how is the server's Reply sent back to the client? 

The text in 14.4.6 won't work if the client is not on the local link:

14.4.6. Sending of Reply messages

   If the Request, Confirm, Renew, Rebind or Release message from
   the client was originally received by the server, the server
   unicasts the Reply message to the link-local address in the
   "client-link-local-address" field.

   If the message was originally received in a Forward-request or
   Forward-release message from a relay, the server places the Reply
   message in the options field of a Response-reply message and unicasts
   the message to the relay's address from the original message.

I guess the text could be re-written to say:

   If the Request, Confirm, Renew, Rebind, Decline or Release message from
   the client was originally received by the server and the IPv6 source address
   was a link local address, the server unicasts the Reply message to the
   link-local address in the "client-link-local-address" field otherwise it unicasts
   it to the IPv6 source address.

But, that's kind of nasty and complicated (why not simply always send back the
Reply message to the source of the client's message except when relayed).

Perhaps a better solution is for the client to include a "Reply-Address" option in
the Request, Confirm, Renew, Rebind, Decline or Release message? If the server
is configured to allow this, it would honor it (except when message was received
via a Relay-Forward).

- Bernie Volz

---

From: Jim Bound <[email-masked]>
Date: Tue, 17 Jul 2001 22:06:53 -0400 (EDT)

geeezzz the text is pretty clear.  If the server "ORIGINALLY" got the
packet then that means it was on link.  Come on .......we need to focus on
stuff we missed not argue semantics.  

my 2cents trying to get this done......

/jim

---

From: Ted Lemon <[email-masked]>
Date: Tue, 17 Jul 2001 19:14:22 -0700

> stuff we missed not argue semantics.  

In the case of a DHCP Renew, the client could have unicast
the message from a different subnet.   In the case of the other
messages, you are correct.

			       _MelloN_