Expansion processing module (epm) – ZyXEL Communications Multi-service Access Platform MSAP2000 User Manual
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7. Product Specification
MSAP2000 Technical Manual V3.0
7-19
7.8. Expansion Processing Module (EPM)
Overview
The Expansion Processing Module (EPM) co-works with the Expansion
Link Module (ELM) to provide capacity expansion for a single node.
The EPM is installed within the extension shelf, whereas the ELM is
installed within the main shelf.
The EPM provides the extension shelf’s with a synchronized clock, and
also converts and transmits the control commands sent from the Main
Processing Module (MPM).
Features
And
Benefits
Panel LEDS indicate status, faults, alarms, and network connection
Timing recovery circuit, with ultra-low jitter
Simplified insertion and monitoring procedures for STM-1 Overhead
Byte
Protection Switch functions
Clock synchronization recovery, and excellent phase lock loop
technologies
Alarm and fault monitoring and reporting
Digital cross-connection for all STM-1 Timeslots
Use of non-volatile memory devices for storage of performance data
Function
Diagram
Application
When more than one shelf is needed, installation of EPM in the
expansion shelf is needed. A corresponding ELM must be installed in
the main shelf and link with EPM using a multi-mode fiber patch-cord.
ELM
MPM
Module
Local node communication
Module
EPM
Module
Local node communication