VPLS Extensions for Provider Backbone Bridging - draft-balus-l2vpn-vpls-802.1ah-01.txt

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VPLS Extensions for Provider Backbone Bridging -
draft-balus-l2vpn-vpls-802.1ah-01.txt

• John Hoffmans KPN
• Geraldine Calvignac - France Telecom
• Raymond Zhang - British Telecom
• Nabil Bitar - Verizon
• Florin Balus, Mustapha Aissoui, Matthew Bocci -
  Alcatel-Lucent

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Scope

• Extensions to existing VPLS Solution to
  accommodate IEEE 802.1ah
• Follows RFC 4762 template
• Focus of this version
• Intra-domain use case
• Integrated PBB VPLS Model

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PBB VPLS Requirements

• Add useful PBB capabilities to VPLS
• MAC hiding, VPN Aggregation
• Maintain MPLS Benefits
• Avoid running STP in the Core
• Traffic Engineered, Resilient Backbone
• Selective introduction of PBB
• Large VPNs, lots of CE switches
• No PBB awareness in core PEs
• Maintain Interoperability
• Native Ethernet Access
• Coexist w/ Regular VPLS/PWE3
• Support both 11 and M1 models
• ISID to VPLS

VPLS Domain 2
PE4
PE3
VPLS Domain 3
VPLS Domain 1
PE1
PE2
PE5
PE6
Ethernet
CE
CE
CE
CE
CE
CE
CE
CE
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Solution Details - PBB VPLS

• PBB VPLS running in Edge PEs
• Handles both I and B components
• CMAC to BMAC mapping
• No BVID tunneling
• 11 Model (ISID to B-VPLS)
• Using only PBB MAC Hiding
• No need to manage ISIDs
• Regular VPLS in PE3, PE4
• B-MAC based forwarding
• No ISID, CMAC - awareness
• Only PWs, no Ethernet UNIs

VPLS Domain 2
PE4
PE3
VPLS Domain 1
VPLS Domain 3
PE1
PE2
PE5
PE6
Ethernet
CE
CE
CE
CE
CE
CE
CE
CE
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Extensions to LDP MAC Withdraw

• Potential Blackholing issue in PBB
• Dual-Homing of CE to PE1, PE2
• Access Topology Change i.e. failure of the
  active link to PE1
• I1 Traffic Blackholed to BM1 (PE1)
• Existing MAC Withdraw in Backbone VPLS should not
  be used
• BM1 is still reachable, no need to flush
• Flush only CMAC -gt BMAC entries
• Proposed Solution
• Flush all CMACs in I1 except the ones owned by
  PE2 (BM2)
• New LDP TLV in Address Withdraw message indicates
  the impacted ISID domain(s) (I1) and the BMAC
  (BM2)

Y X
PE4
B
BM5 BM1
PE3
B
VPLS
I2
PE5 (BM5)
B
X-gt BM1
I1
B
B
PE1 (BM1)
PE2 (BM2)
I1
I1
CE
CE
CMAC Y
CMACs X1-100
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PBB VPLS M1 Model
VPLS Domain 2

• Many ISIDs aggregated inside one B-VPLS
• Less provisioning, PWs in the core
• Good fit for ISIDs that share same PEs
• What if flood containment is required?
• e.g. contain I2 Flooding to PE1, PE2 PE5
• Solution create per ISID Flooding Trees
• ISID-based Group BMAC used by PBB for flooding
• Use LDP to declare, register ISID (Group BMAC)
  location in the B-VPLS context

B
B
PE4
PE3
VPLS Domain 3
VPLS Domain 1
B
B
B
B
I1
I1
I2
I2
I1
I2
PE1
PE5
PE2
PE6
CE
CE
CE
CE
CE
CE
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Next Steps

• More details on Flood containment, Multicast
  Handling
• Interworking between PBBN and MPLS
• Authors would like to request WG Feedback on
  mailing list