Introduction
The Telos Alliance has been an industry leader in providing audio over IP solutions to the media industry since introducing Livewire in 2003. While other AoIP standards have come along, the Telos Alliance prides itself not only on the merits of Livewire but on our product's interoperability.
This document will cover how Telos Alliance devices that support Livewire+ AES67 integrate with Dante devices in AES67 mode.
Using AES67
The Telos Alliance has not implemented Dante. However, Telos and Audinate (inventor of the Dante Protocol) have implemented AES67, the protocol used to connect these two systems. Four points need to be accounted for to configure the system successfully.
A PTP Clock source has to be available to all devices
Session Announcement Protocol (SAP) must be present
Each device must be configured to use an AES67 compatible stream mode
The multicast addresses of the streams that need to be routed
Setting the clock source
AES67 requires the use of a PTP Grandmaster, and all devices must receive clock sync from it to exchange audio. Telos Alliance devices will need to be set to the PTP slave option to receive the PTP clock sync. Please consult the specific product manual for instruction on how to set up clock priority. For Dante devices, no changes will need to be made as they use PTP by default.
Session Announcement Protocol
Session Announcement Protocol (SAP) is a method for advertising what streams are available on the network. SAP is not part of the AES67 standard itself but is one of the optional advertising methods that can be used for AES67. Audinate’s Dante Controller can only route streams that have an SAP announcement.
Some Livewire+ AES67 devices have SAP built-in. With devices that have SAP built-in, once each is configured, interconnecting Livewire+AES67 devices and Dante is as easy as point and click.
The Livewire+ devices that support SAP at the time this document was authored are:
xNode (version specific and must be enabled in the UI)
VX Enterprise
VX Prime Plus
Infinity
This list of devices will continue to grow as time goes on.
If you have a Livewire+ AES67 device that does not support SAP, you will have to manually note and enter the Dante multicast Tx addresses into the Livewire+ device. To add the SAP announcement required for the stream to appear in the Dante Controller, a free tool called RAV2SAP, which ALC NetworX created. Using the RAV2SAP tool, you will manually enter the multicast source addresses of the Livewire+ streams.
For specifics on whether a product supports SAP or activates SAP Announcement, please refer to the product manual.
Configuration
Stream Modes
Both Dante and Livewire+ AES67 have a variety of different stream settings. To send an AES67 stream, both the Dante device and Livewire+ AES67 Devices configurations will need to be adjusted.
Configuring a Livewire+ AES67 Device to send an AES67 Stream
The configuration of a Livewire+ AES67 device to send an AES67 stream is done from the device's web interface. Configuring the source to transmit an AES67 stream can vary slightly from device to device. This document speaks in broad terms, but you can find specifics in each product's manual.
Every Livewire+ AES67 device will have a page where you can configure the Sources. On the Source page, you will also have the option to set the Stream Mode. Depending on the device in question, you will want to set this to type "Low Latency Stereo" or "Stereo 1ms (AES67)". Use the given device's save function to set the Stream mode to be AES67 compatible.
Enabling AES67 on a Dante device
The configuration of the Dante device will be done through the Dante Controller application. Open the Device View, and then open the AES67 Config tab.
If The AES67 Config tab is not present on the Dante device, please consult the equipment manufacturer.
On the AES67 config page, there is a menu called AES67 Mode. In this menu you will see the Current status a device is set to and a field called New where you can set whether the AES67 mode is active or not. If the Current field says Disabled, set the New field to Enabled.
A prompt will appear warning you the device will need to be rebooted for the changes to take effect. Click “Yes” in the prompt, and then click the Reboot button under the Reset Device field.
Choosing non-conflicting multicast address ranges
Next, the Tx Multicast Address Prefix has to be set. This setting selects the multicast subnet on which the Dante device will send AES67 to the network. Dante Controller may choose any multicast address on which to send from within the configured range. This is why it is important to set a range apart from the Livewire+ devices source multicast addresses.
The traditional Livewire channel range is from 1 through 32767, so the multicast subnets that Livewire can be assigned to are 239.192.000.000/15 through 239.196.000.000/15. Livewire+AES67 also allows source addresses to be specified as any legal multicast address, by entering the full 239.x.x.x IP multicast address.
Telos recommends setting the Tx Multicast Address Prefix to a Multicast subnet not used by traditional channel numbered Livewire, as it will help to avoid duplicate multicast addresses on the network.
To set the Dante prefix for your network type the desired value into the New Address Prefix and click “Set”.
With AES67 enabled, open the Transmit tab in Dante Controller:
Select the channel you wish to configure and then open the Create Multicast Flow Panel. Now select the channels that are to be included in the new multicast flow, and click create.
Now on the right side of the screen, you will see the Tx multicast address. Note this address, as you will need it later.
Audio Connections:
For a Livewire+ device that implements SAP, making audio connections with Dante is point-and-click.
Connecting audio from a Dante device to a Livewire+ device with SAP
On a Livewire+ device that has SAP implemented, there is a browse feature, which provides the ability to see the multicast channel as well as the hostname of the Dante device transmitting the stream. The SAP announcement doesn’t contain the channel labels that are visible in the Dante controller. Use the multicast address as the unique identifier for the Dante stream.
On the Livewire ‘Destinations’ web page, click the browse icon for the Destination where you wish to receive the AES67 stream. With the Browse window open, click the AES67 SAP tab, and then select the stream you wish to receive by clicking on the multicast address.
Note on the AES67 SAP tab, you will see all devices (including Livewire+ with SAP) advertised.
Connecting audio from a Dante device to a Livewire+ device without SAP
The other way to receive an AES67 stream from a Dante device is to type in the Dante Tx multicast address directly into the destination field of the Telos Alliance device you wish to subscribe to the stream.
Finding a Dante device’s Tx Multicast Address
Dante Controller automatically generates the Tx multicast address when the AES67 flow is created, from within the range set on the Dante AES67 configuration page. Either use the Dante flow Tx Multicast address that was noted when the flow was first created, or view the multicast address in the Dante controller.
In the Dante Controller open the Device view. Once the Device view opens, select the Transmit tab where the multicast address will be listed on the right side under the Transmit Flows.
Connecting from a Livewire+AES67 device to a Dante device
A Livewire+ device implementing SAP will automatically send SAP announcements, and the Livewire+ AES67 channels will already appear in the Dante Controller window. (See the next section on how to create SAP announcements for Livewire+AES67 devices that do not have SAP built-in.)
Enabling the SAP announcement will vary from product to product. As an example, the xNode, SAP announcements, can be enabled on the Synchronization and QoS web page.
With the SAP announcements enabled, open the Dante controller and locate the AES67 stream you want to route. You can identify the stream by either the multicast address or the source name. In the “Dante Transmitters” list, the multicast address will be listed first followed by the source name from the transmitting Telos Alliance device.
With your Transmitter located, go down the list of Dante Receivers until you locate the device you want to route audio. Click on the + sign to open the route, and place the cross points on the router. Once the green checks appear you have successfully created a route.
Creating SAP announcement for a Livewire+ device without SAP
Multicast Addresses
There is only one way to route audio from the Telos Alliance device to Dante device. SAP announcements must be used to make AES67 streams appear in the Dante Controller window. There is, unfortunately, no manual method to enter streams to receive into Dante Controller.
Because AES67 is being used to connect the two systems together, knowing the multicast address of the Livewire+AES67 stream source will be required.
Finding the multicast address of a Livewire+ AES67 Source
Setting the Livewire Channel or multicast address is a device-specific process. This document speaks in broad terms, but specifics about setting up the Livewire Channel or multicast address can be found in each product’s manual.
There are two ways to configure a Livewire+ AES67 device's stream address. The first is by typing the full multicast address directly into the channel address field:
The other option is to configure a device with a Livewire Channel, and then pull the SDP file out of the device in question. On the page where you set the Livewire Channel, there will be an option to download the Stream Description Protocol (SDP) file. How this is displayed in the web GUI varies so please consult the product manual
With the SDP downloaded, you can change the file extension of the SDP file to .txt, and then when you open the file in a text editor you will see the multicast address for this source.
Generating an SAP announcement using RAV2SAP
Using the free RAV2SAP utility, an SAP announcement can be manually created for any AES67 source.
To create a new SAP announcement for each Livewire+AES67 source:
Press the LOCAL: SDP button.
Either cut and paste the SDP file of the Livewire+ source or cut and paste a template SDP file and edit in the Livewire+ source multicast address, into the “Add SDP Stream” box that opens.
Be sure the LOCAL “AUTO” function is enabled.
RAV2SAP will create SAP announcements from the local manual entries, and now the Livewire+AES67 source will show up in the Dante Controller window and be able to be selected.
An SDP template
The following text is an example of an SDP file and may be used as a template by copying all the lines, and replacing the source multicast address (the red numbers in the “c= “ line), and name (the green text in the “s= “ line).
v=0
o=- 3 1 IN IP4 172.16.248.225
s=xNodeTest
c=IN IP4 239.67.1.1/128
t=0 0
m=audio 5004 RTP/AVP 96
a=rtpmap:96 L24/48000/2
a=recvonly
a=ptime:1
a=maxptime:5
a=ts-refclk:ptp=IEEE1588-2008:E8-EB-11-FF-FE-3A-18-13:0
a=mediaclk:direct=0
a=sync-time:0Closing
Creating a converged AoIP network may seem a bit daunting at first, but it certainly does not have to be. If the steps that are described in this document are taken into account then it should be smooth.
In the event, you do run into any issues or have questions please contact support at support@telosalliance.com or by phone +1 (216) 622-0247.