DMX / Artnet or E1.31 over Wifi..

[Andrew Frazer]

Got a challenge.. Distribute about 100 universes of DMX, across a wide space, without having any wired infrastructure other than Power.. The ground is concrete so digging it up is problematic ( it would be 1000's of meters )..

My gut feeling says Wifi just isn't an option, but maybe i'm being old school..

Anybody got any thoughts about this?

[Jason Kyle]

Use 5.8GHz and split universes over several non-overlapping channels and use
directional antennas or at least narrow beam width omni's. Don't waste your
time with 2.4GHz since the bandwidth is insufficient plus every man and his
dog has an iPhone or whatever probably setup as a wireless hotspot so you'd
always be competing for spectrum.
I would recommend some gear but you might get upset LOL

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[Simon Newton]

I'd talk to the guys at Lumen Radio. I can give you their contact
information if you want.

Simon

[Andrew Frazer]

Do you sell Wireless?

[Andrew Frazer]

The lumen gear is nice, ( have seen it and played with it ) but unless they have something new, they don't' support 100's of universes..

[Mr.Goose]

I've got quite some good experience with Wifi setup, and if you use the right tools such as Ubiquiti or Cisco, it will be easier to use that kind of solution.
In any case, 5Ghz range is the one to use, especially to comply with regulation such as TPC of DFS, but also because of the native design of 802.11a.
Coupled with the proper Ethernet-DMX converters, such as 8 ports node, and using multicast packet such as sACN, you'll be close to the limit of a right bandwidth usage.
Regards

[Hippy]

Hey Andrew,

 

I've been working on compression of DMX for just such purposes, and found over one frame for one universe is pretty useless, though over a group of frames which are destined for separate universes, the resultant compression can be quite significant.  I've used both RLE and DEFLATE and had varying results.   RLE is great if you have lots of zero's, but with every channel at different levels (pixel mapped video for example) it's useless.  DEFLATE is great when your compressing multiple universes at a time, and I could achieve about 500 chunks per second maximum throughput (core i5) bringing 16 universes down to about 3-4kb per chunk,  at 30FPS =ing about 150kb/s (not constant of course).  Even better is processing the DMX and sending delta values across universes rather than full frames (using a 16-bit value for channel/value with a separate upper/lower half universe boundary) - but only where the total size of the delta chunk is going to be less than the compressed chunk.   As a chunk, timing of transmission back to DMX becomes less of an issue also since all universes are decompressed and available at the same time. Obviously I didn't use Art-Net nor sACN, but custom protocol on TCP which was transported over ADSL2 lines so naturally there was latency involved too, so 8 chunks were buffered before playback commenced and that seemed sufficient. 100 universes could be a different story though!!

 

All this is windows, closed source and commissioned work, so completely useless for you and OLA sorry, but the concept of a processed/compressed DMX transport stream between OLA nodes is up for grabs.  

 

Cheers,

 

 

 

[Ryan Wilkinson]

I'd recommend Wifi on the 5ghz. Lumen radio is 2.4ghz. When it has weak signal it skips which is very noticeable in fades. I'd recommend Ubiquiti or Mikrotik gear. Both make great Wifi devices for such a thing and won't set you back hundreds of thousands of dollars. They are very reasonably priced. 

[Stefan Krüger]

We have used the  D-Link DAP-2590 Wireless N Dual Band PoE Access Point on a traid faire setup. we used the 5GHz band and had no problems. The 'Handheld Devices' (I Pod and Pad) never loosed signal.
and also in the other end of the hall the connection was excelent. we only used this connection to send control messages to a server.. so no streaming data.
this device has connections for the antennas so you could exchange the original with some directional...

[mrpackethead]

 Hey Hippy, im interested in pursuing osme kind of compression.  ANy suggestons?

[Ernst den Broeder]

At the risk if adding latency, I think I would try running an OpenVPN tunnel between the end points of the wireless link with the compression feature turned on.  Might not need to reinvent a wheel here.

My $0.00 worth.

[Andrew Frazer]

Thats an interesting idea!

[Hippy]

Any compression will add latency, but a compressed VPN should be faster than capture dmx-compress-transmit-decompress-send dmx.  My setup was non-realtime art installation, but for live purposes it's not really needed, you just duplicate links etc.

Cheers,
Hippy

[Michael Sauder]

You can get routers with dedicated encryption cards, which may speed up the VPN even faster.