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Network timing schemes, External network timing, Figure 1-3 – RAD Data comm IPmux-11 User Manual

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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

Figure 1-3

). 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