Using Net Broadcaster to communicate between multiple computers - your experiences?

  • Tech Staff

    I've been building a project where I'm using the Net Broadcaster to communicate between three machines. It's pretty basic - a master control machine and two secondary machines. Each is connected via a wired LAN, each is running three displays. When the operator hits go on the primary machine, the secondary machines follow suit

    There's a few quirks here and there (and a lot of planning and spreadsheets to keep track of what machine is playing what media on what display). Still, the results have been impressive and reliable, and I was curious if anyone out there in Izzy-land had some neat tips or tricks for working with these patches, or if there was interest in an in-depth tutorial or report on how the system works (including show files).

  • Tech Staff

    I would love to see an in-depth tutorial with a show file.

    The closest I've got is my Mac networking tutorial here, but it's just the setup, not so much the programming end of synching machines.

    It's incomplete and I'm having trouble getting into wordpress to edit it, so please forgive any errors or omissions.

    Best wishes,


  • Beta Platinum


    That sounds amazing. One of the reasons that I first started using Isadora was for the multi-machine functionality. At the time (about 15 years ago) this functionality was available through 'Watchout', and because of what appeared to be strong corporate buy-in that software became, and is still, the standard in many respects. However, the price tag was huge, thinking back if I can remember correctly, Watchout was close to $6000 for a licence. I soon learn't that the humble Isadora software could be configured to do the same thing - using the Machine ID setting in Isadora preferences and the NetBroadcaster actor, and you know it was a fraction of the cost. If I had not been involved with the contemporary dance sector and the dance tech community I may never have come across Isadora or been compelled to look into its features. It was oriented towards artists and experimental creative practices particularly along the vein of the Troika Ranch company.

    I have done many projects centred on the functionality of Net Broadcaster. In those early days linking multiple machines was the only way to get the power for even two realtime video output channels at an acceptable frame rate and resolution. I have also used multi-computer set-ups that provide projection to spatial zones in installation work or as video illumination to discrete areas of a scenographic design. The advancement in computer video power has meant more output channels can run through a single computer, but as we move to 4k or 8k video projects tethering individual outputs to multiple single machines through network synchronisation will be on the cards again.

    One area of the workflow that was always a challenge with network synchronisation of multiple computers was the distribution of the Isadora software licence. Enabling one patch to make changes and then having to relaunch patches to move the licence activation around the rig. It inspired me to invest in multiple simultaneous licenses so that the whole rig is running on fully functional patches (I have chalked up 4 licences for this purpose that have been upgraded to USB keys, so I am little worried about the future cost of Isadora). Imagine getting into a situation where the show is running and suddenly having a problem with a patch that is running in demo mode? Even in development trouble shooting multiple patches and building the synchronised functionality means going from one patch to another on multiple machines. I used a lot of 'Shared Desktop' networking and also KVM splitters in production. 

    Now is possibly a good time to talk about multiple machine integration and solutions.The discussion about licence schemes has not yet identified or suggest a solution for synchronised instances of the software on multiple computers.

    Best Wishes


  • i'm doing this properly for the first time for an installation later this year (see this thread) and have been struggling to get it working smoothly. @Woland has been advising me and his tutorial is the place to go for all the necessary details in setting up a network. Massive thanks! i shall run through the tutorial and test everything in a couple of weeks, once i have another show out of the way.

  • I've been using OSC transmitters/receivers for something similar - except sending the data over the internet between two theatres. The patch is essentially a multi-channel vision mixer with virtual PTZ controls and a cue recall system, and all of the control can be operated either locally or remotely. There's also a couple extra computers in one location with a different patch to run live subtitling (also via OSC). I imagine you could do the same with Net Broadcasters and a VPN - OSC is just a little more convenient, because you can point it directly to the other computer's public IP address.

    Running Isadora on multiple machines is great. Especially with NDI and TCPsyphon to send video around as well as controls. I hope the licensing changes make it a little easier to deal with, but it's a great feature either way.