The MPLS WG Archive

[George Swallow <swallow@cisco.com>]

At 09:21 AM 3/21/2002 -0500, David Allan wrote:

> George: 
>
> Is suggesting that all LSRs have the full internet routing
> table and MPLS full connectivity a realistic example.

I got out of the business of telling operator how to run their networks
long ago.  I would not suggest this, but
our implementation will support it.  The way most ISPs currently
run, turning on LDP without doing anything
else will get you exactly the above.  

> I thought eliminating BGP in the
> core simply meant default route to the BGP speakers, and full one-hop
> mesh of BGP speakers. Otherwise the internet COULD not scale as every LSR
> would require a full routing table, and metrics presumably would be
> leaked from BGP into the IGP. Could such a network **EVER**
> converge?

Yes you can use MPLS to eliminate BGP in the core.  Most ISPs today,
however, are carrying the full internet routing table in *all* of their
routers and they do converge.

...George

> cheers 
> Dave 
>
> > -----Original Message----- 
> > From: George Swallow
> [mailto:swallow@cisco.com]
> > Sent: Wednesday, March 20, 2002 5:59 PM 
> > To: Shahram Davari 
> > Cc: 'Thomas D. Nadeau'; 'mpls@uu.net';
> swallow@cisco.com 
> > Subject: Re: Y.1711 requirements from IETF 
> > 
> > 
> > > Where did you get this " ALL LSPs MUST"
> statement from? May 
> > be you are 
> > > reading a different Y.1711 than I have. All I can
> find are 
> > the following 
> > > statement: 
> > > 
> > > " ... It is strongly recommended that CV OAM
> packets be 
> > generated on all LSPs 
> > > (in order to detect all defects and potentially
> provide 
> > protection against 
> > > traffic leakage both in and out of LSPs).
> " 
> > 
> > I have one customer providing an IP VPN service who has
> >1500 PE 
> > routers and probably well over a million LSPs. 
> Most of the LSPs 
> > represent VPN connectivity can carry very little
> traffic. 
> > 
> > Would you "strongly recommend" that CV OAM
> packets be generated on all 
> > their LSPs at a rate of 1 per second?  Can you
> point to *any* 
> > currently deployed network other than those using MPLS
> solely for 
> > traffic engineering where this would be a good
> idea?  If I'm carrying 
> > the full internet routing table and using LDP
> downstream unsolicited 
> > should every router generate 108,000 (the current
> number of routes) CV 
> > OAM packets per second? 
> > 
> > Perhaps you should revisit this "strongly
> recommended" 
> > recommendation.  Perhaps you should provide for
> generation of CV OAM 
> > packets at rates other than 1  second.
> > 
> > ...George 
> > 
> > ================================================================== 
> > George Swallow       Cisco Systems                  (978) 497-8143 
> >                      250 Apollo Drive 
> >                      Chelmsford, Ma 01824 
> > 
> >