1. BGP VPLS Auto Site ID Bhupesh Kothari (bhupesh@juniper.net)
Kireeti Kompella
Thomas Spencer

2. 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

3. 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

4. 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

5. Auto Site ID Negotiation1 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

6. 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

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