Do I have to set all my devices to PTP clock to use AES67?

Customer Asks

I am trying to integrate AES67 devices into our Livewire network, specifically the Comrex Multirack, and I was wondering if we need to set ALL of our devices to synchronize to our PTP clock to make it work right?

Answer

No, you do not need to set all Livewire devices to be a PTP clock slave. Some devices that aren't fully AES67 compliant can only accept Livewire clock.

What's important is any clocks are all synced together, somehow, so they both have the same reference.

Scenario #1

Usually, you would select a single xNode (possibly two) and set the clock settings on that xNode such that it is the master for both PTP and Livewire.

Telos Alliance xNodes (as of version 2) can produce an IEEE1588-2008 (PTPv2) compliant PTP "ARB" master. An ARB master is an ARBITRARY master. That is to say; it's a proper PTP clock that does not have a GPS master reference. An ARB Master is often sufficient for devices not sharing audio between multiple locations.

To do this;

  1. Using your Web Browser, connect to the xNode you will designate as your PTP + Livewire master.

    The best choice for a master node is one that is centrally located and connects to your core network switch. It should not connect to an edge switch.

  2. Navigate to the Synchronization and QoS page.

  3. Set the Clock Mode setting to "PTP/IEEE 1588 ARB clock class 248 + Livewire Primary master."

  4. Click Apply at the bottom of the page. The change will take effect immediately.

You can only have one Livewire master on your Livewire network. If you have another device set as Always Master, this setting will cause a problem. Please see this document on determining your current Livewire master. If you already have a node set to Always Master, you would need to change it to "3 - default."

Changing this setting will cause a Master Clock election to happen on your system. Changing the master should not cause any problems but, be aware that all devices will begin to "re-sync" to this new Livewire master.

Scenario #2

You already have an IEEE1588-2008 PTP Grand Master, and you want to use that as a clock for both.

  1. Using your Web Browser, connect to the xNode you will designate as your PTP "slave" + Livewire master.

    The best choice for this device is one that is centrally located and is connected to your core network switch. It should not be connected to an edge switch.

  2. Navigate to the Synchronization and QoS page

  3. Set the Clock Mode setting to "PTP/IEEE 1588 slave only + Livewire Primary master"

  4. Click Apply at the bottom of the page. The change will take effect immediately.

This change will force this xNode to become a slave to the PTP clock, but produce the clock for the Livewire network.

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