Cisco 15327 - Manual (Page 256)

17-4
Ethernet Card Software Feature and Configuration Guide, R7.2
Chapter 17 Configuring Cisco Proprietary Resilient Packet Ring
Ring Wrapping
Figure 17-2 Cisco proprietary RPR Ring Wrapping
In case of a ring failure, the ML-Series cards connected to the failed section of the Cisco proprietary
RPR detect the failure through the SONET/SDH path alarms. When any ML-Series card receives this
path-AIS signal, it wraps the POS interface that received the signal.
Note Convergence times might exceed 50 ms in the case of multiple failures in the same ring, if traffic passes
through an ML-Series card configured with DRPRI (in active mode)
during the reloading of the ML-Series
card, or in the case of mismatched microcode images on ML-Series cards.
Note If the carrier delay time is changed from the default, the new carrier delay time must be configured on
all the ML-Series card interfaces, including the SPR, POS, and Gigabit Ethernet or Fast Ethernet
interfaces.
Note ML-Series card POS interfaces normally send an alarm for signal label mismatch failure in the
ONS 15454 STS path overhead (PDI-P) to the far end when the POS link goes down or when
Cisco proprietary RPR wraps. ML-Series card POS interfaces do not send PDI-P to the far end when
PDI-P is detected, when a remote defection indication alarm (RDI-P) is being sent to the far end, or when
the only defects detected are generic framing procedure loss of frame delineation (GFP-LFD), generic
framing procedure client signal fail (GFP-CSF), virtual concatenation loss of multiframe (VCAT-LOM),
or virtual concatenation loss of sequence (VCAT-SQM).
Fiber Cut
ML-Series RPR
Ring Wrap
Ring Wrap
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