1. Nortel Confidential Information 1 VPLS OAM (draft-mohan-l2vpn-vpls-oam) L2VPN WG, IETF-71 (Philadelphia) Mar 13, 2008 Dinesh Mohan (Nortel) Ali Sajassi (Cisco) Deborah Brungard, Henry Fowler (AT&T) Philippe Niger (France Telecom) Simon Delord (Uecomm)

2. 2 Overview draft-mohan-l2vpn-vpls-oam-00.txt presented at IETF-70 (Vancouver) Subsequent discussions & agreements VPLS/H-VPLS PE Model Solution applicability Next steps

3. 3 Solution Overview Solution offers significant functional coverage Proactive monitoring (fault detection) Diagnostics (fault verification, fault isolation) Performance monitoring (frame loss ratio, frame delay/variation Solution is applicable to monitoring: VPLS as Bridged Service (Customer service) VPLS as Emulated (V)LAN (VPLS VSIs connectivity) MPLS domain (PW/LSP Monitoring) Solution proposes using: IEEE 802.1ag/ITU-T Y.1731 for Service/LAN Emulation VCCV (Ping/BFD) for MPLS domain

4. 4 VPLS PE Model Bridge Module VPLS 1 Forwarder VPLS 2 Forwarder VPLS n Forwarder Emulated LAN 1 Interface Emulated LAN 2 Interface Emulated LAN n Interface VPLS UNI PWs Full Mesh Agreement reached that above represents the correct VPLS PE Mode Implied in the draft, and presented in IETF-70 Will be explicitly added to the draft in next revision

5. 5 H-VPLS PE Model Bridge Module PW Forwarder Emulated LAN 1 Interface VPLS UNI Bridge Module VPLS 1 Forwarder Emulated LAN 1 Interface Spoke PW Core PWs full mesh Spoke PE Core PE Agreement reached that above represents the correct VPLS PE Mode Implied in the draft, and presented in IETF-70 Will be explicitly added to the draft in next revision

6. 6 Solution Applicability (1) H-VPLS shown here (same solution applies since VPLS is simplified version) Ethernet Service layer can be monitored via Ethernet OAM and fault is localized to U-PE to N-PE, or N-PE to N-PE, or N-PE to U-PE segments PW OAM (VCCV using BFD/LSP Ping) is used to then determine if Spoke PW or Core PW is at fault Finally, if PWs are up, PW forwarder or VPLS forwarder is the suspect location U-PE Bridge Module VPLS UNI Bridge Module Bridge Module Bridge Module VPLS UNI PW Forwarder VPLS Forwarder Spoke PW Core PW MEP MIP Emulated LAN I/f N-PE U-PE

7. 7 Solution Applicability (2) H-VPLS shown here (same solution applies since VPLS is simplified version) Emulated LAN can be monitored via Ethernet OAM (different MD Level than Ethernet Service) and fault can be localized to N-PE to N-PE connectivity Scales much better than running BFD across each PW in full mesh per VSI PW OAM (VCCV using BFD/LSP Ping) used to determine if Core PW at fault Finally, if PW is up, VPLS forwarder is the suspect location U-PE Bridge Module VPLS UNI Bridge Module Bridge Module Bridge Module VPLS UNI PW Forwarder VPLS Forwarder Spoke PW Core PW MEP MIP Emulated LAN I/f N-PE U-PE

8. 8 Summary General agreement that draft-mohan-l2vpn-vpls-oam is applicable for monitoring VPLS using Ethernet OAM and VCCV/BFD/LSP Ping as described earlier

9. 9 Next Steps Progress draft-mohan-l2vpn-vpls-oam as WG draft Add the explicit model for VPLS and H-VPLS PEs Potentially introduce some description on addressing for emulated LAN interfaces, and brief primer on IEEE 802.1ag/ITU-T Y.1731 Elements of draft-stokes-l2vpn-cfm-vccv-oam-00 will be explored further to potentially include as an appendix Further discussion still occurring on the problem scope and applicability of solution presented in draft-stokes- vkompella-l2vpn-vpls-oam-01 See backup slide

10. Nortel Confidential Information 10 Backup

11. 11 draft-stokes-vkomplella-l2vpn-vpls-oam-01 Disclaimer: This is the presenters view of the problem space based on discussions this week, and the discussions are expected to continue draft is proposing to address problem when implementation/protocol bug may lead to scenario where CPU access of FIB (Forwarding Information Base) may present a different view than data plane access of same FIB AND such a situation is limited to a very small sub-set of MAC lookup entries (e.g. specific customer MAC addresses) This problem certainly does not occur when PBB/PBB-TE is front-ending a VPLS/H-VPLS since monitoring entities and data plane uses the same MAC address space

12. 12 VPLS OAM Requirements & Conformance OAM Requirement draft-mohanComments DiscoveryMulticast LBM (on-demand) CCMs may be used (proactive) Validate OAM monitoring end- points for a VPLS service Instance Fault DetectionCCMs are used – different periodicity is allowed (e.g. 10ms to 10min) Fault detection is a proactive operation Used to detect failure in continuity between VPLS Service Endpoints and also between VPLS Forwarders Fault VerificationUnicast LBMs – VPLS forwarder treat these frames as data frames Connectivity between two monitoring points can be established

13. 13 VPLS OAM Requirements & Conformance OAM Requirement draft-mohanComments MTU Verification and data pattern diagnostics Unicast LBMs with Data or Test TLVTo exercise different MTU sizes or exercise different bit patterns in payload Fault LocalizationLTM/LTR for detecting issues at Ethernet Layer, once a problem has been isolated to specific PW in MPLS domain, MPLS domain mechanism to be used Localize the fault as close to its occurrence as possible Frame Loss RatioUsing statistical sampling described in Y.1731 Determine frame loss performance metric, an integral component of SLAs Frame Delay/VariationY.1731 mechanisms can be appliedDetermine frame delay and frame delay variation performance metric, integral components of SLAs

14. 14