Subject: BGP in L2VPN

From: John Smith <[email-masked]>
Date: Thu, 25 Mar 2004 08:30:24 +0000 (GMT)

Hello,

Can anybody give me a brief idea as to how BGP is used in establishing L2VPNs/VPLS. I am
familiar with how BGP is used in 2547bis networks.

Is easy extensibility provided via AFI/SAFI in MP_REACH_NLRI the reason? Or the fact that
BGP can be used to span multiple networks the main motivation factor?

Regards,
Smith

___________________________________________________________
Yahoo! Messenger - Communicate instantly..."Ping" 
your friends today! Download Messenger Now 
http://uk.messenger.yahoo.com/download/index.html

---

From: Robert Raszuk <[email-masked]>
Date: Thu, 25 Mar 2004 02:58:59 -0800

Hi John,

 > Can anybody give me a brief idea as to how BGP is used in establishing
 >  L2VPNs/VPLS. I am familiar with how BGP is used in 2547bis networks.

I think you will find your answer in the below document:

http://www.ietf.org/internet-drafts/draft-ietf-l2vpn-vpls-bgp-01.txt

> BGP can be used to span multiple networks the main motivation factor?

IMHO the main reason is the observation that for VPLS topologies which 
are by nature full mesh regardless of the number of ASes given VPLS 
spans the fact that BGP is used for auto discovery justifies the 
addition of label block information to the new NLRI format to achieve 
both discovery and signaling in the same protocol. The size of this 
delta addition from the protocol perspective is negligible.

Cheers,
R.