RAD Data comm IPmux-11 Manuel D’Utilisation

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Installation and Operation Manual 
Chapter 1  Introduction 
IPmux-11 Ver. 2.00 
Functional Description 
1-7 
•  Internal timing – in this mode, the Tx clock is derived from an internal 
oscillator.  
•  External timing – in this mode the Tx clock is derived from the external clock 
input. The external clock port also outputs the input clock signal to allow 
connection to other units, if needed. 
 
In adaptive timing the regenerated clock is subject to network packet delay 
variation. That is why the quality of the adaptive clock depends on the quality of the 
network. 
 
Network Timing Schemes 
The following paragraphs describe typical timing schemes and the correct timing 
mode settings for achieving end-to-end synchronization.  
External Network Timing 
When the edges of the network are synchronized by an external network clock 
source, all the IPmux-11 units should be configured to work in loopback timing 
mode (see 
). This topology enables any-to-any connectivity.  
 
Figure 1-3.  IPmux-11 in Loopback Timing Mode 
External timing from the network can also be issued to IPmux-11 by external clock 
input. 
Note