This article originally appeared in the PLSN’s sister publication, Stage Directions (April 2014), continuing a series of technical articles in that magazine including “Ethernet Demystified” (June 2013), “Perplexing Protocols” (Aug. 2013), “Know Your Nodes” (Oct. 2013) and “How Clean Are Your Pipes” (Dec. 2013).
In the past columns (see note above) I’ve written about various hardware options related to your lighting control network. These include nodes, switches, topologies and latencies. If you’ve missed these, be sure to check back in the back editions of Stage Directions (archived on stage-directions.com) for more information on the hardware required to create a modern and reliable network for your console. There is another important factor to consider when designing your system: the software configuration of the network itself. That is the topic I’m addressing below.
Multiple Configurations
One of the great advantages that an Ethernet network gives you is flexibility in configuration, so rather than having to pull different cables to alter a configuration, you can simply change some settings and completely alter the behavior of your Ethernet system.
There are many reasons you might want to alter the configuration of your Ethernet system. Maybe you’re working in a venue that receives different shows bringing their own console and fixtures on a daily or weekly basis, or perhaps you need the flexibility to switch between control consoles for different styles of show.
Using the management tools available, it’s simple to select a port on a particular node and then to define its behavior at the click of a mouse. Let’s examine a couple of examples. .
In System A, the venue network is running as a single console network. The two nodes are patched and operating as 10 universes of Art-Net outputs from the central console (universes 0-9). This allows the production staff to control the whole rig with their console. In System A, the house lights are controlled on universe 9.
System B is a little trickier, thanks to a touring production that is bringing their own console to a venue. But even with their own console, they want to use the venue’s network infrastructure, as they’d rather not run a lot of cables for a one-night show. With network management tools, the venue’s electrician can alter the configuration of the nodes to output different universes of Art-Net data (coming from the touring console) for the touring show’s info, but still send universe 9 Art-Net data from the house console to one single port on the network to control house lights.
By altering the configuration on the nodes, the original patch on the venue’s console can be left untouched. Once the touring production leaves, a simple mouse click will restore the original venue settings. As you can see, the configuration of the network and nodes can have a dramatic impact on the speed of the venue’s turnaround. Rather than running additional cables, a few mouse clicks can get the venue working.
So, how can you adjust all of these settings? Unfortunately, the answer to this is not a simple one. Each node manufacturer designs their own configuration software, and while there are certain parameters that can be controlled from generic software, the configuration method will vary depending on the manufacturer you are working with. Some manufacturers offer configuration through a web-based interface while others require you to run their own proprietary software. A few examples of the configuration software include LumiNet Monitor from Luminex, DMX-Workshop from Artistic License (the makers of Art-Net), and even the web interface for Enttec.
But across all these platforms there are a few general settings, even if they are given slightly different names depending on the manufacturer. I’ve tried to use generic terms here, but be aware that some of the terminology can be different.
- Port: Each input or output from a node is generally referred to as a port. There can be varying numbers of ports on a node, and each can have their own configuration.
- Protocol: Depending on your node manufacturer, you may have the option of multiple control protocols that the node supports. It’s important to match this setting to whatever protocol your console is outputting.
- Universe number: Depending on which protocol you select, the exact numeration of the universe number will be one or more digits. For example, with Art-Net 3, the numeration uses three digits (one single digit each for Net, Subnet and Universe) which make up the universe number as a whole.
- Direction: Some node manufacturers allow you to select whether a port on the node is an input or an output port. Confusingly, some manufacturers consider input to mean an input to the network, while others consider it to be an input to the fixtures. The generally accepted method is that the input and output are relative to the node (i.e., an input to the node comes from a console, while an output goes to a fixture). Refer to the manufacturers documentation on this is really the best advice I can offer.
In addition to these core settings, you may well also be presented with configuration options to: select the DMX refresh rate; enable or disable RDM; make other configuration options which are specific to the manufacturer you are dealing with. In general these settings are best left alone unless you need to make a change—manufacturers spend a lot of time trying to ensure their default settings will work in the majority of cases, and unnecessary fiddling could lead to poor system performance.
Another aspect of many network management tools is the ability to create a visual layout of your networked devices. This allows you to see the topology of your system in a single view, and in many cases also lets you monitor the health and status of the devices. While this feature is not an essential requirement when selecting a network tool, it can save you valuable time by giving you real-world information about which devices dropped offline and what, downstream, is connected to those. After all, a picture paints a thousand words, right?
Troubleshooting Your Rig
As alluded to in the visual layout tool above, while it’s all well and good being able to configure the system another essential function of any network tool is the ability to monitor your rig and, if something goes wrong, to alert you to that as quickly as possible. While failures in networking gear are rare, they can be catastrophic to your control system. I’ll focus on redundancy and backups in another article. For now, we’ll try and figure out the best way to ensure that you become aware of any faults, as soon as they happen. Some tools monitor better than others—and the ability to alert you to faults varies from displaying an error on-screen to generating an email, SMS or even pushing a notification to your iDevice. Depending on your needs and the “mission critical” nature of your system, a once a day “is everything there?” check before the show goes up could be enough for you. When selecting and testing your monitoring system, a simple way to perform a test is to unplug a network node and see what sort of alert happens by default.
Another aspect of good network control software will allow you to save and restore a copy of all the settings throughout your network. While it’s relatively rare, occasionally changing settings on a device might lead you to having a configuration which doesn’t work for your system, which means your system won’t work. By offering a restore option you can get everything back into a known-good state, often with a single click. This can be invaluable for the “nothings working” moment minutes before curtain-up! (We’ve all been there, right?)
This functionality can also be used to restore particular settings depending on the usage of the venue. As in our earlier example with System A and System B, the two configurations could be stored as files and recalled when the system was to be used in each configuration.
Whatever package you choose, the network management tool is likely to be central to your configuration of the system. Spend some time evaluating the options based on which hardware you’ve chosen—not all applications support all hardware. Generally the manufacturers of the software will have a list of supported hardware on their website for you to use as a guide.
Peter Kirkup, vice president of entertainment at LumenRadio AB, is a frequent contributor to PLSN’s sister publication, Stage Directions.
