Pseudowire Redundancy And Active / Standby Dual Homing; Lock Instruct And Loopback For Mpls-Tp Pseudowires - Alcatel-Lucent 7450 Manual

Pseudowire Redundancy and Active / Standby Dual Homing

PW redundancy is supported for static MPLS-TP pseudowires. However, instead of using T-LDP
status signaling to signal the forwarding state of a PW, control channel status signaling is used.
The following PW redundancy scenarios must be supported:
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Note that active/standby dual-homing into routed VPLS is not supported in for MPLS-TP PWs.
This is because it relies on PW label withdrawal of the standby PW in order to take down the
VPLS instance, and hence the associated IP interface. Instead, it is possible to enable BGP multi-
homing on a routed VPLS that has MPLS-TP PWs as spokes, and for the PW status of each spoke-
SDP to be driven (using control channel status) from the active or standby forwarding state
assigned to each PW by BGP.
It is possible to configure inter-chassis backup (ICB) PWs as static MPLS-TP PWs with MPLS-
TP identifiers. Only MPLS-TP PWs are supported in the same endpoint. That is, PWs in an
endpoint must either be all MPLS-TP, or none of them must be MPLS-TP. This implies that an
ICB used in an endpoint for which other PWs are MPLS TP must also be configured as an MPLS-
TP PW.
A failover to a standby pseudowire is initiated based on the existing supported methods (e.g.
failure of the SDP).

Lock Instruct and Loopback for MPLS-TP Pseudowires

MPLS-TP supports lock instruct and loopback for PWs, including the ability to:
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MPLS-TP provides the ability to conduct test service throughput for PWs, through the
configuration of a loopback on an administratively locked pseudowire.To conduct a service
throughput test, an administrative lock is applied at each end of the PW. A test service that
7450 ESS MPLS Guide
MC-LAG and MC-APS with single and multi-segment PWs interconnecting the PEs.
MS-PW (S-PE) Redundancy between VLL PEs with single-homed CEs.
Dual-homing of a VLL service into redundant IES or VPRN PEs, with active/standby
PWs.
Dual-homing of a VLL service into a VPLS with active/standby PWs.
administratively lock a spoke-sdp with MPLS-TP identifiers
divert traffic to and from an external device connected to a SAP
create a data path loopback on the corresponding PW at a downstream S-PE or T-PE that
was not originally bound to the spoke-sdp being tested
forward test traffic from an external test generator into an administratively locked PW,
while simultaneously blocking the forwarding of user service traffic
MPLS and RSVP
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