The MPLS WG Archive

[Jeremy Lawrence <jlawrenc@cisco.com>]

Dmitry is quite correct, but a comment on applicability:
Bi-directional ATM LSPs might be useful for traffic engineering
(for example). However scaling ATM VC-based MPLS to any-to-any
connectivity amongst more than a couple of hundred or so eLSRs
will typically require VC-merge capability. VC merging is an
inherently unidirectional concept, so the applicability of
bi-directional VCs in ATM VC-based MPLS is somewhat limited.

Regards,

Jeremy Lawrence

At 09:12 02/26/2001 -0500, Dmitry Ryumkin wrote:
>Paul,
>
>Generalized MPLS defines procedures for bi-directional LSP setup.
>
>Regards,
>Dmitry Ryumkin
>
> -----Original Message-----
>From:   djiang1@lucent.com [mailto:djiang1@lucent.com] 
>Sent:   Monday, February 26, 2001 8:52 AM
>To:     Paul Moore
>Cc:     mpls@UU.NET
>Subject:        Re: MPLS LSPs and ATM PVCs
>
>
>HI Paul,
>
>I believe RSVP is never intended to set up two LSPs using one single
>operation.  We will have to use two RSVP signalling operations to set up
>the two LSPs, one for each direction, even if the PVC may be used
>bidirectionally.
>
>Regards,
>Jane D. Jiang
>
>
>
>
>Paul Moore <paul-patrick.moore@alcatel.be>@UU.NET on 02/26/2001 08:11:29 AM
>
>Sent by:  owner-mpls@UU.NET
>
>
>To:   mpls@UU.NET
>cc:
>Subject:  MPLS LSPs and ATM PVCs
>
>
>Hello,
>
>I have a question about MPLS and ATM. ATM point-to-point PVCs can be
>either uni-directional or bi-directional. MPLS LSPs are only
>uni-directional. Is there any work being done concerning bi-directional
>LSPs, for example, to allow two LSPs to be established by a single RSVP
>signalling operation?
>
>I've just joined the list, so apologies if this has already been
>discussed.
>
>Thanks,
>Paul
>
>--
>Paul Moore
>Alcatel Bell
>+32 3 450 3536
>paul-patrick.moore@alcatel.be