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Re: GMPLS Sonet extensions
Jimmy,
Connection set-up is performed on a per layer network basis. For its
purpose of setting up a connection, the layer network uses available
bandwidth to that layer network. For the case a protected connection is
to be set up, it is important to know at what level the protection is
required. I.e. this layer network or a server layer network. If it is
the former, the layer network has to create two unprotected connections
starting/ending at bridge/selector functions; e.g. a 1+1 SNC protected
VC-4 connection would be dealt with this way within the HOVC layer
entwork.
However, if it is the latter (server layer network contains protection),
the layer network which sets up the connection doesn't care at all about
protection; e.g. case of a VC-4 connection running over a 1+1 MS
protected line or over a MS SPring protected ring - the HOVC layer
entwork doesn't care about the protection.
Regards,
Maarten
Jimmy Gendron wrote:
>
> 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
> >
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