When planning a Dante audio network, it’s important to consider the network hardware involved.
Dante uses COTS (Commercial-Off-The-Shelf Hardware). This makes it simple to integrate into existing networks, or to design new ones.
The first considerations are whether to use a link local configuration to connect a small array of devices, or to create a larger network, requiring a network switch.
Link Local Networks (without a switch)
A link local network describes when Dante devices are directly daisy-chained to one another, and then to the Ethernet port on the computer. Note that all devices except the last in a chain would need two Dante ports - a Primary and Secondary, and would need to be configured in Switched mode. For a smaller configuration with a handful of devices, this may be perfectly adequate.
Additional Dante devices could be daisy-chained in such a configuration, such as Dante enabled stageboxes, or additional Dante-enabled mixers.
Using Dante With a Network Switch
A larger configuration will require a non-blocking network switch, which is often a ‘managed switch’. Devices are typically connected in a Star Network, with all devices connected to the network switch, and then the network switch connected to the computer’s ethernet port. Even larger configurations involving multiple network switches are possible.
Non-Blocking vs Oversubscribed Network Switches
Most inexpensive consumer switches are ‘oversubscribed’ by design. This means that they have limited bandwidth shared by all ports, and are unable to provide full bandwidth to all ports. This is a major consideration in a Dante network, as predictable data bandwidth is critical. A Non-Blocking network switch is able to provide full bandwidth simultaneously to every port on the switch. This is what is recommended for a reliable and predictable Dante network.
Which Cables Do I Need?
For a 1Gbps network connection, a Cat5e or better cable is required. Cables with higher specifications offer improved EMI/RFI rejection, and are capable of running over longer distances. Typically 1Gbps managed switches are used with Dante networks, so increasing the cable specifications will not increase data rates, but can help network resilience and futureproofing.
For very long cable runs, many managed network switches include SFP/Fibre (Small Form-factor Pluggable) ports. These function just as other network ports, but utilize optical transmission to prevent data loss over long distances. SFP requires specific cables and adapters.
Remember in your installation to allow for patching distance, typically 90 + 5 + 5 meters, otherwise SFP Fiber is needed.
Green Ethernet
Whichever network switch you use, it is essential it is possible to disable Green Ethernet on the device. Green Ethernet dynamically reduces data rates and causes unpredictable behavior which can interfere with Dante network performance.
PoE (Power Over Ethernet)
Many Dante devices support being powered by PoE (Power Over Ethernet). This is an easy and convenient way to power devices, using only an Ethernet cable, which also acts as the Dante AoIP connection. When choosing your network switch, it is sensible to check that it supports PoE, and how much power budget is available to devices.
IGMP snooping
IGMP snooping can help with the optimization of data transmitted across the network, particularly when using Dante devices in multicast. It's important to only have one switch on the network configured as the IGMP querier when enabling this feature. If you do not have an IGMP querier configured on the network, IGMP snooping should be disabled on all switches.
Summary of features to look for when choosing an Ethernet Switch for Dante
- Ability to disable Green Ethernet
- A managed network switch, typically SMB (Small Business Switches)
- Non-Blocking
- IGMP Snooping for traffic optimization
- PoE (not required for x16D, but useful for other Dante peripherals)
- SFP for where long fiber cable runs are necessary
- VLAN - allows you to isolate ports to different IP addresses, segment traffic, and/or allow the creation of redundant networks
- QoS (Quality of Service)
Which network switches do you recommend?
While Universal Audio does not endorse specific products, these devices are good examples of managed network switches that have been tested with x16D.
Netgear M2450-10G2XF-PoE+ 30W
Netgear has designed a range of managed network switches with AoIP in mind.
These have all the features you would look for to create a high quality Dante network.
The OOB (Out Of Band) ports allow you to directly connect a computer in case you have configured the device in a way that locks you out from accessing the main ports.
The combo RJ45/SFP ports allow for connecting SFP fiber for long distance runs. The ports can be trunked to link bandwidth when creating expanded networks with multiple switches.
CISCO Business CBS350-8FP-E-2G Managed Switch | 8 Port GE | Full PoE | Ext PS | 2x1G Combo
This network switch has a very similar feature set, and also can be rack mounted with the included kit.
Netgear 300 Series SOHO Plus (GS305EPP)
5-Port High Power PoE+ Gigabit Ethernet Plus Switch (120W)
This is a small but capable switch, suitable for smaller Dante networks, or expanding a network.
A good recommendation is to choose a network switch manufacturer, and to use switches from the same manufacturer and product range in your network. While mixing and matching switches from different manufacturers can work, there is a greater ease of administration when the switch management systems are all the same. In addition, prioritizing and configuring network traffic can become a more simple process. If there is an I.T. team involved, it’s a worthwhile exercise to consult with them on the switch hardware already in place, and to discuss the best approach for integrating a Dante A/V network.
Adding an Ethernet port to a computer
Many computers do not feature a built-in Ethernet port, but one can be added easily using a USB-C to Ethernet Adapter, or a Thunderbolt dock with an Ethernet port.
Universal Audio has tested some accessories, such as docks and adapters, and confirmed their compatibility with Apollo x16D. They are listed below:
- Belkin USB-C LAN
- CalDigit TS3 Plus 15-Port Thunderbolt 3 Dock
- Anker USB C Hub Adapter, 5-in-1 USB C Adapter
- Startech USB-C to Ethernet Adapter
This is far from an exclusive list, and most similar devices are expected to work well.
Considering network switch hops in your design
When designing a system with multiple switches, there is a tiny latency consideration of 0.1ms per switch hop, from one switch to another. All latency is automatically compensated, but it’s worth checking the latency pane in Dante controller to see if all devices are still able to operate at their designated latency setting.
The good news is this means you can have a lot of network switches before there is any significant impact on the performance of a Dante network. A good rule of thumb would be 10-20 switch hops without significant clocking or latency issues, and that could represent a truly massive network. Minimizing switch hops is of course a good part of the network design process.
It’s best practice to operate a symmetrical network design, in a spine and leaf structure for large AV networks.