Lucent Technologies FT-2000 OC-48 User Manual

Control, Transmission, and Synchronization Interfaces
5-22 Issue 8.0 July 2002
Free Running/Through Timed Configuration 5
The free running/through timed configuration may be used for initial asynchronous
applications and reprovisioned later to the externally timed/through timed
configuration by adding an external DS1 synchronization reference.
The free running/through timed configuration applies to OC-48 point-to-point
applications (with or without FT-2000 OC-48 Repeater Bays) with asynchronous
(DS3) low speed interfaces only.
In the free running/through timed configuration (Figure 5-11), one FT-2000 OC-48
Add/Drop-Rings Terminal times its transmitted signals from its free running
internal oscillator. The internal oscillator at the other FT-2000 OC-48
Add/Drop-Rings Terminal uses the OC-48 line reference signal recovered from
the incoming OC-48 signal to derive timing for its transmitted signals.
The FT-2000 OC-48 Add/Drop-Rings Terminal in the through timed mode also
derives two DS1 synchronization outputs. The LAA18 TG3 (DS1) circuit pack
derives the DS1 synchronization outputs directly from the timing signal recovered
from the incoming OC-48 signal. The DS1 synchronization outputs are made
available to the office BITS clock or other SONET network elements in the office.
For more information about platform timing modes, refer to "Platform
Synchronization" in this section.
Figure 5-11. Free Running/Through Timed Configuration
FT-2000
OC-48
FT-2000
DS3 DS3
Free Running
CO CO
Through Timed

Lucent Technologies FT-2000 OC-48 Specifications

General

Brand	Lucent Technologies
Model	FT-2000 OC-48
Category	Network Hardware
Language	English