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DMX E1.31 behind a second router


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The LOR Document "AN Introduction to DMX and E1.31 for Pixel Control" is an excellent beginner's document for getting started setting up a second router to keep the UDP packets off the main computer network.  I followed the instructions and have LOR S4 Pro running on a WIN-XP system connected to a Linksys WRT400 router to which is also connected a Joshua Systems ECG-DR4 Ethernet to DMX bridge.

Above that is my house network RT-AC68U router and a network of PCs, HUE Lights, Stereo, TVs etc.  The WAN port is plugged into a SHAW Cable Modem.


So we have:

SHAW Modem into RT-AC68U with IP #

    WRT400N is connected via WAN port and assigned by the RT-AC68U

          WRT400N has an internal IP of

          LOR PC is connected to WRT400N and assigned by WRT400N

          ECG-DR4 is connected to WRT400N and assigned fixed via WEB page on the ECG-DR4


From a command.exe window, the LOR PC can ping the ECG-DR4, the WRT400N and any other node on the house network and even (Google) so it has full access to the internet.


Although it's set to the same workgroup (ARTISAN) other than pings in the DOS window cannot use Explorer to access any shared drives on the house network.


The house network can ping the WRT400N router on the IP and get responses.  It cannot ping the LOR PC or the ECG-DR4 on the 192.168.2.xxx subnet.  And because of that it also can't use file explorer to access any shared folders on the LOR PC.


And therein is the problem.  One reason to use the subnet is to keep the UDP packets from flooding the house network and a quick look with wireshark shows that LOR running on a house network PC creates a lot of UDP packets. (as expected).


The second reason is so the LOR PC can just run show software and have new shows placed onto the sequences folder.  That's only possible at the moment using sneakernet and a USB dongle.


Page 33 of the LOR document states it's possible to share data between the networks but it's beyond the scope of the document and to check google.  I've had no luck there.


I've set up static routes on the house network to try to get to via the gateway both with mask and with no luck.  


I suspect the WRTN400N is blocking outside (from its' perspective) access.  But I can't find anything that would allow devices on 192.168.0.xxx access while preventing say from getting in.


Any suggestions?  The information would be a useful addition to the LOR document.




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If both PCs have ethernet and wireless capability, you can do as I did. It took a lot of messing around, but this is what I did. 

My setup is as follows: Computer "A" is my sequencing machine and daily driver, Computer "B" is used just for shows. I needed the ability to communicate between A & B, so when I finish working on a sequence, a simple batch file mirrors my LOR "A" directory with that on "B." I also understood the need to get the E1.31 traffic off of the main network, but that didn't jive with my requirement for comms between A and B, since A is my main computer (and on the home network). 
Then it occurred to me that both machines have both wireless capability and ethernet capability. So, I dug up an old router, and set it up as an access point with an IP address of 192.168.2.x.(note the 2) My main network's ip addresses are 192.168.1.x.(note the 1) Then I connected both A and B to the old access point (wirelessly) and the wireless NICs get an address from DHCP of 192.168.2.x. I give my e1.31 controllers an address of 192.168.2.x, but the wired ethernet NICs on A and B still have an IP of 192.168.1.x.
So after all of this, I have accomplished what I set out to do. A and B can communicate with each other. "A" can sequence, test shows, and be on the main network (read: internet), "B" can run shows. However, the e1.31 traffic is not on the main home network, so now I can have the LOR control panel running with no performance hit on the network whatsoever.
I still don't understand why the LOR comm listener needs to be so chatty, but I'm not a programmer.. What I do know is that when xlights is running (and LOR is not), the network doesn't appear to take any performance hit at all. 
I hope this helped a bit.
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The alternative is to add a second Network Interface Card to the Show Computer and tie that one into the House network.  It will get an IP from the ASUS RT-AC68U and the activity on the show side shouldn't be an issue.  Although I don't know if the UDP broadcast would then be sent to both NICs.


I still think the WRT400N is preventing access from the WAN side much like even if you knew the IP generated by the SHAW CABLE modem you still couldn't get into the 192.168.0.x house network.


This has to be easy once you know how.

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Have you considered a static route to keep the multicast traffic off the house network?

From one of my other posts:

If you are using multicast, it will broadcast across both nics.

You can add a static route that will contain the multicast traffic to the nic you are using for E1.31 traffic ...

route -p add mask <ip of correct pc interface to use> metric 5

The "p" in the route command will make this a persistant route meaning you dont have to set it everytime.


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These are all excellent suggestions.  That is the beauty of IP networking, it is so flexible that you can find many solutions for a problem and each solution has its pros and cons.


The setups shown in my document (even at 30+ pages) can not even be considered 'crawling'.  They are more 'baby rolls on floor to get from A to B'.  In fact, anyone who reads that thing who knows about IP networking probably has had to purchase a new computer monitor.  I'm sure after every page they said 'What the heck is this guy thinking!!!!  That's not the way to do that!!!', and then at some point punched the screen.  They would be right :P

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  • 2 weeks later...


I take it your suggestion is for one PC with two NICs? 

Running WIreShark on my home network PC and filtering for UDP broadcast messages while LOR is running on the show PC on the other router doesn't present any packets from the LOR system.   And the LOR is sending packets to the DR4 Ethernet to DMX board which in turn is sending DMX out to my DMX module.

I've been distracted on other projects for the last week or so but now have a chance to get back at things. 

I think for now I'll use SneakerNet to move any shows developed on a system other than the show computer.  For now it's clearly too complicated to arrange folder sharing between the two networks.



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There is some software called Bind IP that lets you 'bind' specific programs to a specific network connection. You will need two network castles though.

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