User manual

Chapter 3 Device Configuration
18 Cajun M770 Manager User’s Guide
Viewing ATM Clock Synchronization Configuration
Some multimedia applications, such as voice, require that a single clock is
propagated throughout the network. The clock source is usually a Public Telco
switch connected to a local PBX through a telephony network. Using the Cajun
M770 ATM Device, up to four external references can be configured, two from
ATM ports and two from external E1/T1 sources. These are all directed to the
M-SPS module which selects one of them to be the source input timing device. It
uses the selected source to generate a 19.44MHz clock which is distributed to all
modules. This is used by all ATM ports to synchronize Sonet frames.
The ATM Clock Synchronization dialog box provides information about the
method currently configured for synchronizing the clocks in the Cajun M770
Device.
To view and edit clock synchronization parameters from Chassis View:
1 Click .
OR
Open the
Configuration
menu and select
ATM Clock Sync
. The ATM Clock
Synchronization dialog box appears.
Figure 3.6 Clock Synchronization Dialog Box
The ATM Clock Synchronization dialog box shows the module type, status, and
current source of clock synchronization. It also provides a table of clock
synchronization parameters for all the clock sources, and allows you to edit their
configurations.
To edit the configuration of a clock synchronization source:
1 Select one of the sources from the table.
2 Modify the parameters in the
Row Configuration
area of the dialog box.
3 Click
OK
. The configuration of the clock source is modified.