DMX and Art-Net


    Aug 22 2014 | 7:01 pm
    Hello,
    I am very interested in DMX and the new technologies surrounding DMX. I have a couple of questions and was wondering if I could get some advice. Firstly I am curious about Art-Net vs. sACN. Which one is better and which one is the one to use (i.e. what are the differences)? It seems to me like Art-Net is in more use even though sACN is supposed to be the succesor...Is this correct?
    Also, am I correct in my understanding that ACN (real ACN) is supposed to be the succesor to DMX, with many benefits?
    For Art-Net devices, many, such as the ENTTEC ODE just have an Ethernet port for their input. I am assuming I can just plug an ethernet cable from my computer to the ODE device and it will work, but, if I wanted to also use wired internet on the computer, I would plug my computer AND the ODE into a router, correct?

    • Aug 22 2014 | 7:40 pm
      sACN isn't really the 'successor' to Art-Net and DMX. Full ACN is supposed to be the successor, but it hasn't taken off in any serious way. No lighting fixtures or consoles support it, and it doesn't seem to be high on anyone's agenda. There's a lot of reasons for this, from software development to data distribution, but the upshot it that if it ever takes off, it will take a good while to trickle down to the average theatre show/gig. DMX is here to stay for a good while.
      sACN is basically a compatibility layer for sending DMX/Art-Net style data (lists of 8-bit values) over ACN networks. The only real difference compared to Art-Net is that sACN sends data using multicast (as opposed to broadcast). This is only really a problem for large networks and other performance-critical applications.
      The ODE can plug via a router or switch yes, it's like any other piece of networking equipment.
    • Aug 22 2014 | 9:08 pm
      Thank you for your answer David, as well as for all your work with DMX. Multicast sounds the same as broadcast though so I am curious about the difference.... Also, do many fixtures support sACN? Is there any value on learning about these other protocols or is it safe to stick with Artnet
    • Aug 22 2014 | 9:23 pm
      If you broadcast a packet, you send it to every device on the network, whether they've asked for it or not. This means that sending broadcast generates a large amount of network traffic (the more connected devices, the more traffic). Multicast allows devices to register that they are interested in receiving packets from a particular multicast IP. This request is understood by switches and routers, so when a packet is sent on a multicast address it is only routed to the devices which have asked for it.
      Art-Net was originally broadcast only, but the more recent revisions of the protocol have introduced unicast Art-Net, which is now the preferred mode of operation. If a console has Art-Net node discovery, then it's likely to use unicast transmission to send Art-Net.
      I wouldn't bother with sACN. Art-Net is far more widely supported and understood. The multicast advantage doesn't really apply unless you're dealing with large scale multi-purpose show control networks.
    • Aug 22 2014 | 10:06 pm
      Thank you so much for your detailed explanation. You're the man.
    • May 22 2015 | 6:34 pm
      Can you help me get artnet out of max For Live