MPLS & Ethernet OAM Interworking (draft-mohan-pwe3-mpls-eth-oam-iwk)

1. MPLS & Ethernet OAM Interworking (draft-mohan-pwe3-mpls-eth-oam-iwk) PWE3 WG, IETF-71 (Philadelphia) Mar 10, 2008 Dinesh Mohan (Nortel) Nabil Bitar (Verizon) Philippe Niger (France Telecom) Simon Delord (Uecomm)

2. Overview • draft-ietf-pwe3-oam-msg-map provides mapping of defect states between PW and associated AC • However, Ethernet AC not covered in the draft since Ethernet OAM was work in progress at the time • This draft specifies the mapping of defect states between Ethernet AC and associated Ethernet PW • IEEE 802.1ag and ITU-T Y.1731 activities have now been completed, therefore, this activity is timely.

3. Reference Model • Ethernet ACs do not necessarily have to be a physical link between CE and PE • CE is not necessarily an end customer device, rather is a device in client network connecting to PSN for emulated service

4. Forward and Reverse Defects • PE1 may detect forward defect in local Ethernet AC via one of: • AIS alarm generated by CE1 • Failure in local link on which AC is configured • Failure to receive CCMs if local MEP is configured on the AC • PE1 may detect forward defect in PW via one of: • Forward defect indication received from PE2 • Unavailability of PSN path in PW domain to PE2

5. Forward and Reverse Defects (cont’d) • PE1 may be notified of reverse defect in local Ethernet AC via: • CCMs with RDI bit set when MEP is configured on the AC • PE1 may be notified of PW reverse defect via: • Reverse defect indication from PE2

6. PW Status and Defect Notification Options • Use of Native Service Fault Notification • Ethernet PW currently do not specify native service fault notifications • However, if a MEP is created on PE associated with Ethernet PW, native service notification options include: • AIS frames sent by MEP to peer MEP on other PE (convey forward defect) • Suspension of CCM frames (convey forward defect) • RDI bit in CCM frames (convey reverse defect) • Use of PW Status Notification (for MPLS PSNs) • Forward defect: logical OR of local AC (ingress) receive fault AND local PW (egress) transmit fault • Reverse defect: logical OR of local AC (egress) transmit fault AND local PW (ingress) receive fault • Use of BFD Diagnostic Codes • When using VCCV • CV type of 0x04 used to indicate BFD for PW fault detection only and notification is carried out via Status Notification • CV type of 0x08 used to indicate BFD for both PW fault detection and AC/PW fault notification, only BFD is used for fault notifications

7. Ethernet AC & PW Defect States Interworking (1) • PW Forward Defect States Interworking (entry) • PE1 ability to receive user traffic from CE2 is impacted • Notify CE1 • If MEP is configured on AC, CCM not turned ON, send AIS • If MEP is configured on AC, CCM turned ON without Interface Status TLV support, stop sending CCM • If MEP is configured on AC, CCM turned ON with Interface Status TLV support, reflect state in Interface Status TLV • Notify PE2 • Via Native Service OAM mechanisms, if supported on PE for PW; ELSE • Via PW status notification or via VCCV-BFD diagnostic code (if CV type of 0x08 negotiated) • If forward defect entered via loss of control adjacency, no action is needed • PW Forward Defect States Interworking (exit) • Reverse of the above steps

8. Ethernet AC & PW Defect States Interworking (2) • PW Reverse Defect States Interworking (entry) • PE1 ability to transmit user traffic to CE2 is impacted • Notify CE1 • If MEP is configured on AC, CCM turned ON, set RDI bit in CCMs • PW Reverse Defect States Interworking (exit) • Reverse of the above steps

9. Ethernet AC & PW Defect States Interworking (3) • AC Forward Defect States Interworking (entry) • PE1 ability to receive user traffic from CE1 is impacted • Notify PE2 • Via Native Service OAM mechanisms, if supported on PE for PW; ELSE • Via PW status notification or via VCCV-BFD diagnostic code (if CV type of 0x08 negotiated) • Notify CE1 • If MEP is configured on AC, CCM turned ON, set RDI bit in CCMs • AC Forward Defect States Interworking (exit) • Reverse of the above steps

10. Ethernet AC & PW Defect States Interworking (4) • AC Reverse Defect States Interworking (entry) • PE1 ability to transmit user traffic to CE1 is impacted • Notify PE2 • Via Native Service OAM mechanisms, if supported on PE for PW; ELSE • Via PW status notification or via VCCV-BFD diagnostic code (if CV type of 0x08 negotiated) • AC Reverse Defect States Interworking (exit) • Reverse of the above steps

11. Next Steps • Two possible options include: • Merge this draft with draft-ietf-pwe3-oam-msg-map • Pursue this draft as PWE3 WG draft • Authors are open to either option, however, if draft-ietf-pwe3-oam-msp-map is close to completion, then option 2 might be best • This draft if structured to be a standalone document with references to draft-ietf-pwe3-oam-msg-map • Authors would like to get a sense from the room and request the group to make this a WG draft • since it addressed a major gap in current AC and PW defect mappings