Demand test descriptions and error codes - Avaya Support

This creates a hierarchy where the master PN receives timing from the public network, and
every other PN derives its timing from the master through the CSS. See Figure 74: Traditional
Sync Operation.
Figure 74: Traditional Sync Operation
Public
Network
Typically, a pair of interfaces from the public network are configured — one as a primary and
one as a secondary. The IPSI/Tone-Clock in the Master PN can:
● Lock onto either interface
● Switch between them in the event of a failure
In the event of a dual failure, the Tone-Clock in the master PN can generate its own timing and
keep every PN synchronized. However, these PNs would not be synchronized with any other
public-network interfaces that exist in any of the PNs.
When a center stage is implemented via an ATM network, it is possible to obtain timing from the
ATM network. For more information, See ATM-SYNC (ATM Synchronization).
S8700-series IP-PNC
Primary
Secondary
Master
PN
S8700-series IP-PNC Server Sync Operation
Center
Stage
Switch
For an S8700 IP-PNC system, its port networks (PNs) are connected via the customer’s IP
network. This network cot be used to transmit timing information between the PNs. The
complete set of PNs need not be synchronized with each other. Inter-PN bearer traffic is carried
as VOIP, while the Media Processors’ internal jitter buffers deal with differences in transmission
rates.
894 Maintenance Alarms for Communication Manager, Media Gateways and Servers
Slave
PN
Slave
PN
Slave
PN