AudioCodes IPmedia 3000, Installation Manual

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Installation Manual 60 Document #: LTRT-94704
Mediant 3000 & IPmedia 3000
Pin FE Signal GE Signal
7 N/C Rx D+
8 N/C Rx D-
Figure 3-13: RJ-45 LAN Ethernet Network Port and Connector
3.3.4 Cabling PEM for BITS Mode
When the Mediant 3000 is configured (software) for the Building Integrated Timing Source
(BITS) synchronization mode, you need to follow the procedure described in this section for
appropriate cabling.
Notes:
•
Cabling for BITS mode is applicable only to Mediant 3000.
•
For a detailed explanation on configuring the BITS clock synchronization
mode, refer to the
User's Manual .
In BITS mode, both active and redundant blades are synchronized by two BITS source
interfaces (input trunks). The BITS trunks flow through the two SA/M3K blades (located in
the front panel - refer to ''Alarm, Status and Synchronization Blade'' on page
33 ), each with
a designated timing module, which is located on the PEM modules. Two SA/M3K blades
are required to ensure seamless clock operation in case of failure in one of the SA/M3K
blade's timing-modules (i.e., clock redundancy). When one of the BITS reference clock
sources fails, the Mediant 3000 automatically switches to the secondary source as a
reference clock for the whole system.
For Mediant 3000 Simplex systems (i.e., single blade), if the primary BITS clock source fails
(and clock fallback is enabled), the device uses the secondary BITS clock source. However,
during the transition between the failed clock and the secondary clock, the device remains
in hold-over mode until the secondary clock is acquired.