Lucent Technologies 555-233-119 slave, master, .

DEFINITY ECS Release 8.2 Maintenance for R8.2csi 555-233-119 Issue 1
April 2000
Maintenance Objects
3-221ATM-SYNC (ATM Synchronization)
3
This synchronization source is then distrib uted to all of its OC3 Interface
Modules. Each ATM Expansion Interface circuit p ack uses the received d ata
stream from the ATM switch to generate a timing signal. The Tone-Clock circuit
packs in the EPNs use this signal to generate timing for all the circuit pac ks in
their respective EPNs. All PNs, in the above mentioned sc enario are designated
the
slave port networks. The ATM switch is the master that contains the system
synchronization source. If the pri mary synchronization reference does not
provide a valid timing signal, ATM synchronization maintenance infers a switc h to
the secondary reference
.
If the primary synchronization referenc e is not providing a valid timing signal, the
system automatically switches to the secondary synchronization reference. If the
primary synchronization reference is in valid, and if the secondary reference does
not provide a valid timing signal or is not administered as a synchronization
reference, the switch infers that the local oscillator of the ATM switch provides the
system timing source. If the system is u sing the local oscillator of the ATM switch
as the system timing source bec ause the primary and sec ondary references are
providing invalid timing signals, when either the pr imary or secondary reference
becomes valid ag ain, the system switches back to the primary or secondar y
source. When both the primary an d secondary source become valid, the system
switches to the primary sourc e, since the primary source is alw ays preferred over
the secondary source wh en both sources are equally healthy.
Figur e 3-10 depicts a simplex ATM PNC with T1/OC3 synchronization reference
into the ATM switch.