RE: GMPLS Sonet extensions

[Jimmy Gendron <jgendron@hyperchip.com>]

Vishal,

thank you for the details. How the protection type is managed? Is it the
SONET LSP that set up an optical LSP with, for example, 1+1 protection?
Which entity is responsible to deal with protection at first when we try to
set up an MPLS LSP with 1+1 prot through SONET?

Thank you,

Jimmy

-----Original Message-----
From: Vishal Sharma [mailto:vsharma87@yahoo.com]
Sent: Friday, June 08, 2001 10:06 PM
To: 'Susumu Yoneda'; Jimmy Gendron; ccamp@ops.ietf.org
Subject: RE: GMPLS Sonet extensions


Jimmy, Susumu,

Your idea (assuming a peer model) is basically correct. Since all nodes
have the same view of the network, you could compute an ERO at the
ingress router and have the PATH message follow the hop-by-hop route
to the egress router.
(Note, however, that the PATH message will travel
on the out-of-band IP control network; therefore, it would be non-associated

signaling.)

Also, Susumu, if the peer model is in effect, then all messges will,
in fact, have to be shared by all nodes, since that is precisely what
the "peer model" implies.

But you do have to be careful about what "LSP" you are requesting, since the
characteristics of the requested LSP are not interpreted in the same way by
the
various pieces of equipment in your figure. (A SONET ADM requires a
different
way of defining a circuit than an IP router or an OXC.)
Therefore, one possibility would be to do a "layered setup", where an LSP
at the lower layer is setup before the PATH message at the higher layer
is tunnelled over it or allowed to propagate further.

For example, when the PATH message for the packet
LSP arrives at the SONET ADM, the peer SONET ADMs would have to setup
a corresponding SONET circuit between themselves, and then either tunnel
the PATH message for the packet LSP over this circuit, or (assuming your
out-of-band network), at that time, allow the PATH message for the packet
LSP to propagate to the next MPLS router. (The setting up of the SONET
channel, likewise, would be a recursive process, with the OXC first setting
up an optical lightpath between themselves, and tunneling the request to
set up the SONET channel over it, once that lightpath is setup.)

A more detailed discussion of this subject, with corresponding animations
and figures, that you may also find helpful is available in a talk I gave at
MPLSCon'01, and can be found at:
http://www.mplscon.com/missing_presentations.htm
(Dynamic path establishment in MPLS-controlled multi-service networks.)

-Vishal


On Friday, June 08, 2001 6:00 PM, Susumu Yoneda
[SMTP:yone@japan-telecom.co.jp] 
wrote:
> Hi,
>
> I also assume that there would be an out-of-band signalling network based
on
> a suite of GMPLS protocols including LMP. I think there will be issues to
> address whether all messages will be shared by all nodes, i.e router,
> SDH/SONET, and OXC or not. This will be a part of security issues.
> -------------------------------
> Susumu Yoneda   tel +81 3 5540 8493
> Japan Telecom    fax +81 3 5540 8485
> Information & Communication Labs.
> e-mail  yone@japan-telecom.co.jp
> -------------------------------
> -----Original Message-----
> From: owner-ccamp@ops.ietf.org [mailto:owner-ccamp@ops.ietf.org]On Behalf
Of
> Jimmy Gendron
> Sent: Friday, June 08, 2001 10:01 PM
> To: 'ccamp@ops.ietf.org'
> Subject: GMPLS Sonet extensions
>
>
> Hi,
>
> I used to read almost all stuff regarding GMPLS since a week. I understand
> most of the architecture, but I still have a question since the beginning;
> as an unified control plane, how do the routing/signaling protocols
exchange
> informations on a configuration like this:
>
> MPLS Router -----> SONET ADM ------> OXC  -----> WDM ----------- WDM
> -------> OXC --------> SONET ADM --------> MPLS Router
> (Ingress)
>
> Its a basic point to point configuration, but it will allow me to
understand
> the basic features of GMPLS. If I want to create an MPLS LSP between the
two
> MPLS routers, how do the RSVP PATH message is sent to the network?
(Assuming
> that we have an out-of-band IP control network running LMP)
>
> My guess is that the PATH message will leave the ingress router with a
PATH
> message with a calculated ERO. It assumes that the network is in respect
> with the peer model...everyone have the same routing table and know the
> actual network topology. So, my PATH message will follow the CSPF (ERO)
and
> go to the egress router. Am I right?
>
> Best regards,
>
> Jimmy Gendron
>