Control, Transmission, and Synchronization Interfaces
Issue 8.0 July 2002
5-7
!
CAUTION:
All DS3 and EC-1 signal outputs from the FT-2000 OC-48 Add/Drop-Rings
Terminal for 2-Fiber Rings must be properly terminated at all times.
Therefore, these outputs must be connected to cross-connect panels that
have internal 75-ohm terminations (for example, Lucent Technologies
cross-connect panels meet this requirement) or other working transmission
equipment (for example, DACS III-2000 Cross-Connect System or
DDM-2000 Multiplexer) where the associated low speed interfaces are
equipped. When operating the FT-2000 OC-48 Add/Drop-Rings Terminal
with cross-connect panels that do not automatically terminate the DS3 and
EC-1 signal outputs, 75-ohm termination plugs must be placed at the
cross-connect panel.
Care must be exercised during maintenance operations to ensure that the
DS3 and EC-1 signal outputs are not inadvertently unterminated. In
releases prior to Release 5, if DS3 and EC-1 signal outputs are not
terminated properly, false trouble conditions could be reported by the
FT-2000 OC-48 Add/Drop-Rings Terminal. In Release 5, it is still
recommended that DS3 and EC-1 signal outputs be terminated properly.
However, if DS3 and EC-1 signal outputs are not terminated properly and
the unterminated DS3 and EC-1 ports in the drop direction (from OC-48
line) are in the NMON state, false trouble conditions will not be reported by
the FT-2000 OC-48 Add/Drop-Rings Terminal.
The FT-2000 OC-48 Add/Drop-Rings Terminal for 2-Fiber Rings has no fixed
connection, or association, between the low speed interface circuit packs and the
OC-48 high speed lines (add/drop traffic) or between high speed line 1E and 1W
(through traffic). User specified cross-connections allow any low speed interface
slot to be cross-connected to any STS-3 tributary of OC-48 high speed line 1E or
1W. They also allow any incoming STS-3 tributary of OC-48 high speed line 1E or
1W to be cross-connected to the same-numbered outgoing STS-3 tributary of the
other OC-48 high speed line. The FT-2000 OC-48 Add/Drop-Rings Terminal for
2-Fiber Rings offers an STS-3 time slot assignment capability that allows the
following cross-connections:
â– 1-way cross-connections (available in Release 4.1 and later releases)
â– 1-way-DRI cross-connections (available in Release 4.1 and later releases)
â– 2-way cross-connections (available in Release 3 and later releases).