Re: [dhcwg] 3rd & *FINAL* try before ABANDONING draft-ietf-dhc-dhcpv6-stateful-issues-04.txt

["Leaf Yeh" <[e-mail]>]

BV - I'm really surprised at the lack of feedback given that the community
at one time was very interested in this work and wanted to resolve the
issues with "combining" RFC 3315 and 3633. This also was supposed to be
input into the RFC 3315bis work .

 

If DHC-WG really wants a RFC3315bis, I suppose we definitely need its scope.


Will 3315bis obsolete 3315 only, or cover the scope of both 3315 and 3633? 

 

If the answer is the later, I guess 3315bis will also cover this piece of
work.

 

 

Best Regards,

Leaf

 

Ps. http://www.ietf.org/proceedings/88/minutes/minutes-88-dhc 

<quote>

Tomek Mrugalski then presented the RFC-3315bis design team slides.

    

    Tomek: Kick off RFC3315 bis and Design Team Formation

    Tomek: - using issue tracker for WG

           - call volunteers to joint in "Editorial Team",5-6 persons

    Suresh Krishnan: site-local addrs still in use

    Tomek: ok, solved

    Jinmei Tatuya: we can go over the email archive for checking issues

    Tomek: big task

    Alex Petrescu: split the work

    Suresh: separate a mailing list for design team, ask authors of

      RFC3315 first, the issue trackers to be managed well

    Kim Kinnear: How are old RFCs deprecated?

 

The following volunteered during the meeting to be on the design team:

Suresh Krishnan, Andrew Yourtchenko, Alexandru Petrescu, Sheng Jiang,

Daniel Migault, Marcin Siodelski, Tomek Mrugalski, and Bernie Volz.

Michael Richardson volunteered immediately after the meeting. Tomek

and Bernie will review and follow up with team.

 

Note: Everyone is encouraged to provide RFC 3316/3633 corrections and

areas with interoperability issues or needing clarification.

</quote>

 

 

 

From: dhcwg [mailto:[e-mail]] On Behalf Of Bernie Volz (volz)
Sent: Monday, November 25, 2013 5:57 AM
To: [e-mail]
Cc: Ole Troan (otroan); Ralph Droms (rdroms)
Subject: Re: [dhcwg] 3rd & *FINAL* try before ABANDONING
draft-ietf-dhc-dhcpv6-stateful-issues-04.txt

 

The 04 draft has expired and I'd like to publish a revised draft.

 

However, as this is a WG document, I can't just make changes on my own - I
need support for the WG for changes.

 

And I sent this out a while back (twice) but, to my knowledge, received NO
input.

 

So, I will once again solicit feedback as to whether people support this or
not.

 

If I do NOT receive any feedback (either positive or negative), the only
course of action is to ABANDON the stateful-issues work as it seems that
there is NO interest in this work and therefore no reason to continue it.

 

I'm really surprised at the lack of feedback given that the community at one
time was very interested in this work and wanted to resolve the issues with
"combining" RFC 3315 and 3633. This also was supposed to be input into the
RFC 3315bis work .

 

-          Bernie

 

From: [e-mail] [mailto:[e-mail]] On Behalf Of
Bernie Volz (volz)
Sent: Monday, June 10, 2013 3:55 PM
To: [e-mail]
Cc: Kim Kinnear (kkinnear); Ole Troan (otroan); Ralph Droms (rdroms)
Subject: [dhcwg] 2nd Try - draft-ietf-dhc-dhcpv6-stateful-issues-04.txt

 

As this is a WG document, I would like some feedback from people about
whether the proposed change is "valid". I received no feedback or discussion
about this Rebind issue. While this technically doesn't change 3315 as 3315
permits a Rebind to return the NoBinding status in the Reply and 18.2.4
never mentions adding 'new' addresses, I think this may well be a valid
interpretation of what is not said in 18.2.4.

 

To perhaps make the intended change more clear, here's some potential
wording for replacement text of 18.2.4 of RFC 3315. Some text was moved and
new text has + in column 1. This may not be the final text (suggestions to
improve greatly welcome).

 

18.2.4. Receipt of Rebind Messages

 

   When the server receives a Rebind message that contains an IA option

   from a client, it locates the client's binding and verifies that the

   information in the IA from the client matches the information stored

   for that client.

 

+  If the server finds the addresses in the IA for the client and the

   server determines that the addresses in the IA are appropriate for

   the link to which the client's interface is attached according to the

   server's explicit configuration information, the server SHOULD send

   back the IA to the client with new lifetimes and T1/T2 times.

 

   If the server cannot find a client entry for the IA and the server

   determines that the addresses in the IA are not appropriate for the

   link to which the client's interface is attached according to the

   server's explicit configuration information, the server MAY send a

   Reply message to the client containing the client's IA, with the

   lifetimes for the addresses in the IA set to zero.  This Reply

   constitutes an explicit notification to the client that the addresses

   in the IA are no longer valid.  In this situation, if the server does

   not send a Reply message it silently discards the Rebind message.

 

+  If the server cannot find a client entry for the IA and the server

   determines that the addresses in the IA are appropriate for the link

   to which the client's interface is attached according to the server's

   explicit configuration information, and the addresses are not in use,

   the server MAY assign the addresses to the client and send a Reply

   message to the client with new lifetimes and 1T1/T2 time for the

   bindings. If the server cannot assign the addresses to the client,

   the server returns the IA containing no addresses with a Status Code

   option set to NoBinding in the Reply message.

 

+  Note: A server SHOULD NOT provide additional bindings to the client

   as the client could accept a Reply from a different server (this is

   the same issue as in the Discussion under the Rapid Commit option,

   see section 22.14).

 

   The server constructs a Reply message by setting the "msg-type" field

   to REPLY, and copying the transaction ID from the Rebind message into

   the transaction-id field.

 

   The server MUST include a Server Identifier option containing the

   server's DUID and the Client Identifier option from the Rebind

   message in the Reply message.

 

   The server includes other options containing configuration

   information to be returned to the client as described in section

   18.2.

 

 

There are four possible response to a Rebind (note that I'm restricting my
wording here to addresses as that is all RFC 3315 speaks to, but you can
replace "address" with "delegated prefix" for 3633):

1.       No response. This is used when the server does not have a record of
the bindings and cannot determine whether the bindings are on-link. As the
addresses may be valid, but this server has insufficient information to
determine this, it is best it remain silent. If other servers respond, the
client will have its information. Otherwise, the client will deal with the
issues when the lifetimes expire.

2.       Reply with Bindings with 0 lifetimes. This is used when the server
determines that the bindings are not on-link.

3.       Reply with NoBinding status code(s) response. This is used when the
server is unable to assign the addresses requested or the client needs "new"
information. As this will cause the client to return to sending Request, it
provides the server another and better chance to provide the client complete
information.

4.       Reply with updated lifetimes and T1/T2 times. This is when the
server has a record of bindings and they are still valid or is able to
assign what the client already has.

Based on other changes to stateful-issues, I'd also indicate that the server
MUST pick one of these for ALL of the IA_* options. And, I think the server
should pick the lowest numbered respond based on processing each binding.

 

Note again the server should NOT allocate any "new" addresses to the client
even if its current configuration would dictate as it would not know if the
client uses this information, UNLESS the server is configured honor Rapid
Commit. If there is new information that should go to the client, the server
should either respond as in case 3 above or initiate a Reconfigure of the
client.

 

-          Bernie

 

From: [e-mail] [mailto:[e-mail]] On Behalf Of
Bernie Volz (volz)
Sent: Monday, May 13, 2013 2:04 PM
To: [e-mail]
Subject: [dhcwg] draft-ietf-dhc-dhcpv6-stateful-issues-04.txt

 

Hi:

 

This is an updated version of this document. It includes a few minor changes
from the WG last call and is there mostly to restore this document as it has
expired a few days ago.

 

I still have a bunch of the comments from the WG Last Call in
January/February to address.

 

There is also one key issue that will need some discussion from the WG. In
particular, handling of Rebind requests.

 

One major flaw with respect to the Rebind message handling in RFC 3315 and
this draft is that as the client has sent the Rebind to multiple servers,
all of which could respond, there is no way for a particular server to know
whether its Reply will be accepted by the client. This is essentially the
same issue with using Rapid Commit in a Solicit when there are multiple
servers available.

 

I think the Rebind processing should essentially be changed so that a server
will either return everything the client requested to be rebound (and
nothing more) or nothing (in which case it returns NoBinding status for all
bindings).

 

If the server is willing to extend (or grant) the existing leases, the
Rebind is fine. If the server is unwilling or unable, then it should force
the client back into a Request phase as described in RFC 3315 section
18.1.8. That 18.1.8 section is also the only place a NoBinding status
appears to be mentioned in terms of the Rebind.

 

-          Bernie