Today's production systems are heavily reliant on 3rd party networks for control & configuration, to interconnect system components, or to interface to other systems. With it comes the reality that our systems will never be better than our networks and the performance of the network becomes critical to success.

Switches

Switches are available at various prices ranging from tens/hundreds of dollars to many thousands of dollars. Many of them will look and feel the same to the user and probably are for simple tasks that do not require a performance guarantee from the network. Example of this could be 1 computer connected to configure one device does not require much switch throughput nor timeliness of the connection.
What normally sets more expensive switches apart are their internal components, software as well as technical support provided by the switch manufacturer. Switch component differences commonly include more PoE power capabilities, mechanical robustness, upgraded/internal/redundant PSU, robust lockable connectors but also the microprocessors and memory that mange the switch and its traffic.

Ethernet inherently moves non-linear packages around and includes mechanisms to re-send and re-arrange them if the network has an issue. Real-time media such as audio and video are very sensitive to these non-linearities as we want our audio and video to be continuous and without any gaps. To practically transport real-time audio and video over networks the network must be robust and capable of transporting without any interruptions. For this many technologies, such as PTP clocking, QoS prioritization and VLAN traffic segregation tools, which are all pieces of software running on our switches, have been deployed and are in regular use in our systems to ensure that what is most important gets to its destination on time and intact.

We all know the experience when our own computers start to slow down and have issues. Perhaps it is because of the 50 browser taps that are open, along with the 100Mb PowerPoint, while listening to Spotify in high resolution whilst monitoring a live stream. At some point computer can no longer keep up and deliver upon the most important tasks.

Now, let's imagine that a switch is a computer…

Just like the computer the more stuff we put through a switch the more drain it will put on the switch’s resources. At some point the switches which perfectly handled two ports and some light configuration starts to feel it. As we add more and more Dante, AES67, NDI etc the switch processor and memory won’t be able to keep up with prioritizing the most important real-time media and we will experience choppy audio or worst case a disconnection because our PTP derived clock became unstable, while we discover our beautifully architected VLAN are actually manged by the same microprocessor and memory as the rest of it.

“Is this switch xyz capable?”

We commonly get asked if a xyz switch isn’t perfectly capable to be used with our systems and our applications engineers do collect our own and our customer’s experiences on the Clear-Com Solution Finder where you can look up various types of switches and recommended settings for them.

Switch capability should always be considered a starting point in specifying a network.

Switch Capabilities vs. Network Capabilities

A network can comprise of multiple switches, their connected devices, and their traffic. One of those switches can be perfectly capable of delivering excellent performance for xyz real-time media protocol. However, is the network the capable switch is a part of capable of the xyz real-time media protocol after it has been loaded with 36 NDI sources, 384 inputs of Dante (32 of which are multicast), remote control for mixing consoles, loudspeaker systems, CCTV system, steaming Lighting Control, and the client’s internet connection for the conference?

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