Lucent Technologies R5SI Computer Hardware User Manual


  Open as PDF
of 2643
 
DEFINITY Enterprise Communications Server Release 5
Maintenance and Test for R5vs/si
555-230-123
Issue 1
April 1997
Maintenance Object Repair Procedures
Page 10-947MMI-SYNC
10
MMI-SYNC
NOTE:
Refer to ‘‘Troubleshooting Multimedia Call Handling (MMCH)’’ in Chapter 5
for MMCH troubleshooting information.
Each Port Network (PN) must have a TN787D or later MMI circuit pack assigned
as the Multimedia Interface (MMI) master synchronization source for that PN. If
one or more MMI circuit pack is administered in a PN, one MMI circuit pack is
designated as the master synchronization source for all MMI circuit packs within
that PN.
The MMI circuit pack generates a synchronization signal and puts that signal on
the TDM bus. Other MMI packs or any other circuit pack within a PN can listen to
this signal and “synchronize up” to it. The first MMI circuit pack inserted in a PN
is normally designated as the master. As subsequent MMI packs are inserted,
they are instructed to listen and synchronize to the time-slot of the master MMI. In
the unlikely case of an MMI losing this reference, an uplink message is sent from
the MMI circuit pack that lost the signal to maintenance, which also clears the
“event” counter on this MMI with a downlink message. This forces the MMI circuit
pack to return the current state of the synchronization signal. If the signal is still
lost, then the recovery algorithm is entered. Note that during this time, the MMI
circuit pack synchronizes to its internal clock, and there should be no service
disruption. A loss of synchronization is usually the result of a circuit pack failure.
The maintenance strategy is to switch the master source away from the bad pack
to another healthy MMI circuit pack within the PN.
1. Where P is the port network number (1 for PPN and 2 or 3 for EPN); C is the carrier designation (for
example, A, B, C, or D); and SS is the address of the slot in the carrier where the circuit pack is
located (for example, 01, 02, ..., and so forth).
MO Name (in
Alarm Log)
Alarm
Level Initial Command to Run
1
Full Name of MO
MMI-SYNC MINOR test board PCSS l r# Multimedia Interface Circuit Pack