BGP VPLS Auto Site ID Bhupesh Kothari (bhupesh@juniper.net) Kireeti Kompella (kireeti@juniper.net) Thomas Spencer (tsiv@att.com)

VPLS Site ID Requirements Site IDs configured on each VPLS PE must be unique per VPLS domain. Exception is multi-homing. Site IDs must be dense per VPLS domain. Good allocation: 10,11,12,13,50,51,52,53

VPLS Auto Site ID Goals Eliminate the need to provision site IDs Distributed approach with no central device (like PE, RR) allocating site IDs for better scaling and fault tolerance properties No extra state on PEs beyond what already exist today Backwards compatibility with current explicit site ID allocation approach Procedures should work when VPLS domain span multiple AS

VPLS Auto Site ID Approach Each PE keeps track of site IDs already in use and claims an unused ID when it needs one If two PEs claim the same site ID, then they run a collision resolution algorithm to resolve the collision in favor of one of the claimants Algorithm guarantees convergence: all sites will ultimately pick unique site IDs Simple optimizations make the chance of a collision extremely small in real life Explicitly configured site IDs always win over dynamically generated ones

Auto Site ID Negotiation 1 2 Claim Wait to receive NLRIs Send a claim adv. Wait for collision No collision=>send a real adv. Withdraw claim adv. Real Claim 3 8 4 Real 5 8 1 5 1 8 E D A C 1 8 6 1 8 VE ID B 2 1 8 Offset Range BGP VPLS NLRI

VPLS Auto Site Restrictions Site IDs need to be explicitly configured with multi-homing PEs cannot tell that they are connected to the same site and coordinate site ID allocation

VPLS Auto Site ID Details are in: Questions? draft-kothari-l2vpn-auto-site-id-00.txt Questions?