Subject: Issues with 14.3.1

From: "Bernie Volz (EUD)" <[email-masked]>
Date: Thu, 19 Jul 2001 16:24:17 -0500

In Section 14.3.1 of -19 (Creation and Sending of Request Messages)]
it says:

"If a client has no valid IPv6 addresses of sufficient scope to
communicate with a DHCP server, it may send a Request to obtain
new addresses."

- What difference does it make even if a client has addresses of
sufficient scope to communicate with a server? Seems to me we should
just say "If a client needs to obtain addresses, it may send a
Request to obtain [new] addresses."

- What exactly is meant by "new" addresses? I understand that the
client should not use a Request message to "renew" addresses, but
must these be "new"?

Suppose we have a client that is very simple and has no permanent
storage. So, each time it boots it simply does a Request on IAID 0.
If the client reboots, it will do the same (since it does not
remember anything about old "leases"). Now, does this mean that the
server MUST NOT allocate the client the same address on each
Request? Or is this a server policy issue? The text in Section
14.4.1 isn't of any help. If the server does allocate new
addresses, what does it do with the old addresses (put them on an
unusable list until the valid lifetime expires)?

Again, perhaps this is considered a server implementation issue?

My own feeling is that the server should give out the "old" addresses
if they are still valid (addresses with a preferred lifetime of 0
should likely not be included because as this is not a Renew, those
addresses really have no value to this client.) The server should,
of course, consider giving the client new (more) addresses as needed
(either to replace those no longer valid or per whatever policy the
server has).

- Bernie