Thought I'd pass this info along...
I'm rebuilding my PC (upgraded to Win8.1) and that is causing me to reinstall software including xLights -- which talks to the EtherDongle.
As you may be aware, the EtD uses multicast E1.31. When your PC sends multicast in large number of packets (20 per second, and maybe 32 512-channel universes) it could have a negative effect on your home network. I have had some of my PCs slow to a crawl when xLights is sending multicast traffic.
To solve this, I added a second NIC for my E1.31 traffic. When xLights sends multicast packets, it MAY send it to the wrong NIC, but to tell your PC which NIC to use, you can create a "static route".
Here is my setup:
192.168.1.24 :: my PC's IP address on my home network
192.168.0.24 :: my PC's IP address on my E1.31 network (this network is shared with the EtD !!)
Run this command on your PC one time: (the -p option makes it persistent -- or retained after a reboot)
route -p add 239.255.0.0 mask 255.255.0.0 192.168.0.24 metric 1
Note the IP address "192.168.0.24" is specified -- this is the IP address for my NIC on the E1.31 network.
The network 239.255.0.0 and its associated mask is used to specify multicast traffic -- all multicast traffic will be sent over the second NIC.
(Thanks David for originally helping me with the syntax!)