Re: High level comment on draft-li-ccamp-confirm-data-channel-status-00.txt,

["Diego Caviglia" <Diego.Caviglia@marconi.com>]

Hi Dan,
        first of all I think that the ID addresses a real problem.

Regarding the bits and bytes I prefer to not implemet new messages but just
updateds the existing ones that seems to fit to the problem.

I think that having a timeslot that should be usable that is actually
unusable is a failure from the control plane prespective.

So I think that is correct to use the Fault Management Messages to convey
information about unusable channles.

Regards

Diego



Dan Li <danli@huawei.com>@ops.ietf.org on 23/08/2006 09.55.49

Sent by:    owner-ccamp@ops.ietf.org


To:    xuhuiying@huawei.com, "Zafar Ali (zali)" <zali@cisco.com>, MEURIC
       Julien RD-CORE-LAN <julien.meuric@orange-ft.com>
cc:    ccamp <ccamp@ops.ietf.org>

Subject:    Re: High level comment on
       draft-li-ccamp-confirm-data-channel-status-00.txt,

Hi,

Thanks Julien and Zafar for your comments. I agree with Julien. This I-D
just wants to provide a control plane tool to detect the inconsistent data
channel status in the tranport plane.

Actually I have received several private emails think this I-D addresses a
real problem, but regarding the new LMP messages which are introduced in
this I-D, some people pointed out that the already deployed channelstatus
messages (id = 17, 18, 19 and 20) may be extended to carry also the
timeslot information instead only data link. But I have a concern that the
Fault Management Messages usually are triggered by fault detection, these
messages should not be sent if no fault is detected. The confirmation of
data channel status may need to be performed periodically or triggerd by
user.

I would like to hear from you guys, what's your comments? Not only the
concerns raised above, but also other issues in this I-D.

Regards,

Dan

----- Original Message -----
From: "MEURIC Julien RD-CORE-LAN" <julien.meuric@orange-ft.com>
To: "Zafar Ali (zali)" <zali@cisco.com>; <xuhuiying@huawei.com>;
<danli@huawei.com>
Cc: "ccamp" <ccamp@ops.ietf.org>
Sent: Tuesday, July 11, 2006 2:31 AM
Subject: RE: High level comment on
draft-li-ccamp-confirm-data-channel-status-00.txt,


Hi Zafar.

I don't really get you on this. I figure out you're referring to
removing the connection states when RSVP refreshes are not received any
more, aren't you? If so, I'm afraid this is not enough for transmission
devices, where resources can be physically cross-connected even though
there is no (or no longer) corresponding RSVP state. Therefore having a
mechanism to avoid such discrepancies would be welcome.

Regards,

Julien


P.S.: If you totally rely on a management plane, I agree this should be
useless (e.g. the NMS should already know if a cross-connection deletion
failed, cf. Diego's 2nd slides seen this morning).

________________________________


From: owner-ccamp@ops.ietf.org [mailto:owner-ccamp@ops.ietf.org] On
Behalf Of Zafar Ali (zali)

Dear Authors,

RSVP refreshes do this job, so I am not sure motivation for this draft/
LMP extensions.

n.b. The draft state, "Although such a situation can be resolved through
the use of the Acceptable Label Set object in GMPLS signaling [RFC3473],
such a procedure is inefficient since it may require an additional
signaling exchange for each LSP that is set up", so I assume that RSVP
signaling is present (Although I did not understand the quoted statement
from the ID). Even if RSVP is not present, e.g., optical core is
completely controlled by a management entity, I would argue introduce
presence of LMP.

Thanks

Regards... Zafar