Dual-Homing Protection for MPLS and MPLS-TP Pseudowires Weiqiang Cheng, L. Wang, H. Li (China Mobile) K. Liu, J. Dong (Huawei) S. Davari (Broadcom) A. D'Alessandro (Telecom Italia) IETF91 PALS Honolulu 2014
Background Work was presented in IETF 88 and 90 Split the draft according to PWE3 chairs’ suggestion: Framework and scenarios of dual-homing PW protection Protocol extensions for dual-homing protection with static MPLS-TP PWs
Benefits of Dual-homing Protection Local protection Avoid PW switchover due to AC failure Avoid AC switchover due to PW failure PSN tunnel protection is no longer a MUST
PE Architecture Update Dual-homing PE Device Forwarder DNI PW Service PW Peer Dual-homing PE Device AC DNI PW between dual-homing PEs can carry traffic during failure Forwarder is responsible for switching traffic between AC, service PW and DNI PW.
dual-homing coordination One-side Dual-homing Scenario PE3 PE1 PE2 CE2 CE1 DNI PW linear protection Working PW Protection PW AC Redundancy Mechanism dual-homing coordination Service PW AC1 AC2 Can Provide protection for: AC failure PE failure PSN network failure
One-side Dual-homing Scenario PE3 PE1 PE2 CE2 CE1 1 DNI PW linear protection Working PW Protection PW AC Redundancy Mechanism dual-homing coordination AC1 AC2 Can Provide protection for: AC failure PSN network failure PE failure
One-side Dual-homing Scenario PE3 PE1 PE2 CE2 CE1 2 DNI PW linear protection Working PW Protection PW AC Redundancy Mechanism dual-homing coordination AC1 AC2 Can Provide protection for: AC failure PSN network failure PE failure
One-side Dual-homing Scenario PE3 PE1 PE2 CE2 CE1 3 DNI PW linear protection Working PW Protection PW AC Redundancy Mechanism dual-homing coordination AC1 AC2 Can Provide protection for: AC failure PSN network failure PE failure
Two-side Dual-homing Scenario PE3 PE2 CE2 CE1 DNI PW linear protection Working PW Protection PW AC Redundancy Mechanism AC1 AC2 PE1 redundancy mechanism 4 2 3 5 1 Can Provide protection for: AC failure PE failure PSN network failure
General Procedures Dual-homing PEs need to exchange PW state and switchover coordination request to synchronize the protection switching Forwarding behavior of dual-homing PE is determined by: Status of Service PW Status of AC Status of DNI PW AC Service PW DNI PW Service PW AC DNI PW Forwarding Behavior Active Up Service PW <-> AC Standby Service PW <-> DNI PW DNI PW <-> AC Drop all packets
Next Steps Solicit comments from WG WG adoption?