The MPLS WG Archive

[Giles Heron <giles@packetexchange.net>]

On Fri, 2002-07-26 at 09:30, neil.2.harrison@bt.com wrote:
> Giles....my apologies, but I have to correct you here as I feel you are
> misrepresenting an important issue....please see below.

no misrepresentation intended.  No correction required ;-)

> regards, Neil
> 
> > -----Original Message-----
> > From: Giles Heron [mailto:giles@packetexchange.net]
> > Sent: 26 July 2002 01:44
> > To: Jothilingam, Vasudevan " "(Vasu)
> > Cc: IETF MPLS List
> > Subject: RE: initiating a discussion on mpls singaling protocols
> > 
> > 
> > On Wed, 2002-07-24 at 18:55, Jothilingam, Vasudevan (Vasu) wrote: 
> > > Giles
> > > 
> > > I understand that, I just wanted make sure..
> > > So are we suggesting that Just have LDP. Well, I am not 
> > sure what will that
> > > buy us 
> > > without TE.
> > 
> > No - I am suggesting that we need LDP, and that we also need a TE
> > mechanism.  Given that RSVP-TE is so widely deployed I think the
> > opportunity for CR-LDP has passed. 
> NH=> There is general LDP and targeted LDP....the former creates mp2p
> entities, but I believe your requirement is for the latter which creates p2p
> entities (though I assume you could use RSVP-TE for this too, so its not
> clear to me that LDP is a 'must' in your case.....but please correct me if
> this is not the case).
[snipped to end]

I want *both* mp2p LDP and targetted LDP.

I want the former because it:

1) minimises the number of labels required in the core - O(N) rather
than O(N squared).

2) enables auto-generation of full mesh connectivity (each PE advertises
a single label for itself which reaches all other Ps and PEs).

3) is a good last resort even when RSVP-TE is being used (because of the
above)

I want the latter for L2 over MPLS.

Sure the L2 stuff could be done with RSVP-TE (someone specified this in
a draft at one stage I think?) but LDP seems a to me a much more natural
way to advertise labels over a single hop than RSVP-TE.

Giles
 
-- 
=================================================================
Giles Heron    Principal Network Architect    PacketExchange Ltd.
ph: +44 7880 506185              "if you build it they will yawn"
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