Nortel Networks NN43001-301 - Manual (Page 167)

Description 167
Figure 66
Example 7, Network Clocking with MUX
In this example, the direct connection to the CO (without a MUX) should be
used as a primary clock reference because this is where the least amount of
hardware is involved. The MUX must pass the clock and not generate its
own clock; in other words, it must be a slave (not Free Run). Synchronized
clocking is required.
Modes of operation
There are two modes of operation, tracking mode and free run (non-tracking)
mode.
Tracking mode
In tracking mode, the Primary Rate Interface (PRI) or Digital Trunk Interface
(DTI) loop supplies an external clock reference to the onboard clock
controller. Two PRI or DTI packs can operate in tracking mode, with one
defined as the primary reference source for clock synchronization, the other
defined as a secondary reference source. The secondary reference acts as
a back-up to the primary reference.
Nortel Communication Server 1000
ISDN Primary Rate Interface Installation and Commissioning
NN43001-301 02.03 Standard
Release 5.5 7 December 2007
Copyright © 2003-2007, Nortel Networks
.