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RE: [Softwires] BGP TE attr last call by softwires WG (2nd question)



Igor,

Doesn't this defeat auto-discovery?  I.e., how is a new PE added to a
given L1VPN?

Thanks,

John 

>-----Original Message-----
>From: Igor Bryskin [mailto:i_bryskin@yahoo.com] 
>Sent: Friday, August 29, 2008 5:51 AM
>To: Yakov Rekhter; Lou Berger
>Cc: Yakov Rekhter; Adrian Farrel; ccamp@ops.ietf.org; 
>softwires@ietf.org
>Subject: Re: [Softwires] BGP TE attr last call by softwires WG 
>(2nd question)
>
>Yakov,
>
>You said:
>
>
>... And while on the subject of scaling, please keep in mind 
>that BGP only stores L1VPN routes on PEs that have sites of 
>that VPN connected to them, and on an RR if used, but *not* on 
>any of the P routers. In contrast, rfc5252 (OSPF for L1VPN 
>autodiscovery) results in storing *all VPN TE information for 
>all the VPNs* on *all* the IGP nodes, both P and PE. So, 
>clearly BGP-based approach scales better than OSPF-based approach.
>
>Yakov.
>
>This is not true in case of multi-instance OSPF: one can build 
>an overlay interconnecting PEs via one or small number of Ps 
>using IPinIP tunnels and run in this overlay an instance of 
>OSPF specifically designated for distribution of L1VPN 
>information. In this case the OSPF solution won't scale any 
>worse than the BGP approach. Note. that rfc252 never said that 
>the instance of OSPF used for flooding of the L1VPN 
>information must be the same instance that is used for the 
>distribution of IP-related LSAs.
>
>Regards,
>Igor
>
>
>
>