Subject: RE: soft permanent lsps

From: Juha Heinanen <[email-masked]>
Date: Mon, 6 Mar 2000 08:53:47 +0200 (EET)

Theimer Thomas writes:

 > don't you need exactly the same functionality when MPLS is used to control
 > optical lambda routers?  In this case the label represents the wavelength on
 > the outgoing interface.

yes.  may be curtis could comment on how this can be achieved using his
tunneling scheme.

 > However, you may also need some way to address a
 > specific port (unless all ports have individual IP addresses, which may not
 > always be the case) on your (lambda) router.

i don't see why interfaces in optical switches could not be identified
by ip addresses especially if the control plane is based on ip.

 > It would be nice to have a
 > common generic mechanism for signalling and addressing that covers both
 > applications, perhaps based on your draft. I have not seen any detailled
 > specs on this from the optical folks.

the only thing that would need to be changed in the sementics of the label
value and that can be taken care of in the base ldp documents.

-- juha

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From: Curtis Villamizar <[email-masked]>
Date: Mon, 06 Mar 2000 12:13:11 -0500

> yes.  may be curtis could comment on how this can be achieved using his

Since we've had some clarifications from Kireeti and I've been
exchanging some private email with Yakov, it appears that the ideas I
put forth and the PSC in draft-kompella-mpls-optical-00.txt are very
similar.

The only thing that I proposed that is not covered is the conventions
for the ERO that would be needed to do transparent tunnels and the
local configuration at the ingress to map a fixed label to a tunnel
that is localized entirely to the ingress LSR really could be
documented as a usage in an informational RFC.

The idea is that the outer tunnel simply provides a means to get
across a major region of the topology.  The RSVP adjacency could be
through the tunnel or as Yakov pointed out, somewhat out-of-band
through a simple technique already mentioned in the draft:

   If the LSR at the tail of the FA-LSP is not capable of packet
   switching, the Path message is unicast over the control plane to the
   tail of the carrier LSP, without the Router Alert option.

> value and that can be taken care of in the base ldp documents.

I think you should take a second look at
draft-kompella-mpls-optical-00.txt and
draft-kompella-mpls-bundle-00.txt.

Both draft may need some clarification since it was only after some
email exchange that I better understood how the authors intended to
use this.  [Or maybe I'm just denser than most readers.]

Curtis

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From: Juha Heinanen <[email-masked]>
Date: Mon, 6 Mar 2000 19:43:45 +0200 (EET)

>    tail of the carrier LSP, without the Router Alert option.

in case of optical SPLSPs the lambda device connected to the terminating
interface of the optical SPLSP may not participate in any kind of mpls
signaling.  there must be a means for the originating lambda switch to
select the lambda to be used for the optical SPLSP at the terminating
interface.

-- juha