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Prior to configuring the Timing Synchronization Priority List, configure the IMG 1010 - Logical IMG and then the IMG 1010 - Physical IMG objects.
Primary and Secondary Reference Timing are hard-coded and are automatically configured. If Primary Loop and/or Secondary Loop Timing is going to be used, configure the Primary and/or Secondary Loop timing source on the DS-1 within any Bearer or Signaling interface other than the two Signaling interfaces that have the Primary and Secondary Reference sources hard coded to them. To configure, click on either the Bearer Spans or Signaling Spans object in the configuration tree.
When the Bearer or Signaling Spans pane appears, highlight one of the Bearer Interfaces in the Object Table at the bottom of the pane. Right click and select either Set Primary.
Repeat for the Secondary Loop timing source. Select Set Secondary.
Once all timing sources have been configured the sources need to be prioritized. Right-click the Physical IMG and select New Timing Synchronization Priority List. The Timing Synchronization Priority List pane appears as displayed below
Click in the Timing List field under the User-Specified tab and an Arrange Items dialog box will appear. The priority is displayed from top to bottom. The uppermost entry gets the highest or first priority and then the priority decreases as you move down the list. To change the priority, highlight one of the entries and click on the Up or Down button to move the entry up or down the list. Highest priority in the screen below is the Primary Reference and lowest priority is Free Running.
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The Primary Reference Port is hard-coded so that the Signaling/Timing interface 0 on the rear of the IMG will always be designated as Primary Reference.
The Secondary Reference Port is hard-coded so that the Signaling/Timing interface 1 on the rear of the IMG will always be designated as Secondary Reference.
Any of the other Bearer Interfaces on the rear of the 2020 IMG can configured to accept a Primary Loop or Secondary Loop timing reference.
For more information, refer to the IMG 1010 - Timing Synchronization Priority List and IMG 1010 - Loop Timing Configuration topics.
10.3.3 Software
Primary reference and secondary reference are hard coded so they are always configured to accept a loop timing source on TDM Signaling Port 0 and TDM Signaling Port 1 on the IMG. Primary loop can be configured on any bearer offset as shown below.
Right-click the Physical IMG and select New Timing Synchronization Priority List. The Timing Synchronization Priority List pane appears. See Below
The priority which the IMG will use the timing ports is generated here. A drop down menu in each of the fields will allow the user to change the priority.