Sending UDP packet in parallel to 3 devices

MDNARD10:
IThere must be some simple solution, besides MULTI-CASTING.

What makes you think multicast is not simple and there should be a simpler solution?

Multicast is supported by ethernet directly and is the most efficient way to send to a group of targets.

Broadcast is a little simpler - no special enable neccessary -,
but with broadcast all node would be forced to receive the traffic.