RDMNet

What is RDMNet?

RDMNet is a new, open protocol developed by ESTA to define a standard access method for RDM over ethernet. We built RDMNet functionality into LXNettools from the beginning to get a head start when devices start being deployed with this protocol.

Why should I care?

E1.33 RDMNet is a ratified ANSI standard created by a working group of industry peers from a vriety of fields and interests. This means that throughout the development of the protocol, a wide variety of opinions and voices were heard and able to develop the standard. This gives us a framework for allowing devices to interoperate effectively, and allows developers (like me), to be able to focus on one standard. This allows the end user to have the confidence that the protocol has undergone rigorous testing, as well as allowing purchasing stakeholders to be comfortable in the knowledge that they can purchase devices from one manufacturer without worrying about compatibility with system 'x'

How does it work?

RDMNet has been designed to work with both existing systems and those of the future, and as such introduces to us a few new concepts. The first of these is the scope. Every device in the system has a scope, which is a user-definable string, so you can give your devices a logical name based on, say, their location. Multiple scopes are possible in each system, so you could for example have a scope that defines your house lights, your architectural fixtures in the foyer, and so on.

Messaging is handled by a broker, a device that is connected to by a controller and passes mesages to the client devices, as well as buffering and sharing those responses with other controllers in the system. A broker can be a standalone device, or embedded in a device such as a lighting console. Each scope can only have one active broker at a time.

Without meaning to over-simplify, that's about as far as we need to go. Devices with an appropriate scope announce themselves to the broker, and the broker handles RDM messaging to these devices from the controller, be they devices passing through a node or gateway, or devices diretly connected to the ethernet network. As to when we'll see this implemented, it's over to the manufacturers now, the standard is ratified as ANSI E1.33, so it's time we saw some implementations.

For now, if you want to experiment with some of the features of RDMNet, ETC have an excellent suite of programs available at their ETC Labs GitHub, and we test out implementation in LXNettools against this for now until more devices are available.

Happy experimenting!