Specifications

Chapter 4 Troubleshooting and Diagnostics Installation and Operation Manual
4-12 Monitoring Performance MPW-1 MP-4100 Ver. 2.0
When a pseudowire is used as a Megaplex-4100 timing reference source, the
timing source display includes information on the state of the pseudowire
adaptive clock recovery mechanism.
³ To display the pseudowire adaptive clock recovery mechanism state:
1. Navigate to Monitoring > System > Timing.
2. You will see the Timing screen. The information displayed on the screen
depends on the currently used timing source.
Table 4-7 explains the
information displayed when a pseudowire serves as the reference source.
Table 4-7. Timing Monitoring Parameters
Parameter Description
Active Clock Displays the type of timing reference source in use, Master of Fallback
Source Displays the selected nodal timing mode:
Internal – Timing locked to the MPW-1 internal oscillator
Rx Clock – Timing locked to the recovered receive clock signal of a user-selectable
interface, including a pseudowire configured as timing reference source
S Subsystem – Timing locked to the clock signal provided by the SDH/SONET
subsystem
Recovered – Timing locked to the recovered receive clock signal of a user-selected
pseudowire
Rx Clock Identifies the timing reference source in use: module type, its I/O slot number, and
the specific port. A pseudowire is identified as Recovered ID#X (PW#YYY), where X is
the index number of the pseudowire selected as recovered (adaptive) timing using
the System > Clock Source screen, and YYY is the pseudowire index number
Holdover Indicates whether the nodal timing subsystem is in the holdover state (Yes) or not
(No).
The nodal timing subsystem enters the holdover state when all the configured
sources (master and fallback) fail. In the holdover mode, the maintains the internal
reference frequency at the last value acquired before the failure. This situation
persists until at least one of the configured reference source returns to normal, and
thus is selected again as reference
Recovered Clock
Status
Displays the current status of the pseudowire adaptive clock recovey mechanism:
Free Run: indicates that the clock recovery mechanism is not locked to any clock.
Frequency Acquisition: indicates that the clock recovery mechanism is learning the
frequency of the selected reference.
Rapid Phase Lock: indicates that the clock recovery mechanism is in the training
process.
Fine Phase Lock: indicates that the clock recovery mechanism successfully completed
the training process., and is now locked. At this stage, the clock recovery mechanism
provides a stable clock of good quality.
----- : the adaptive clock recovery status is not relevant.