after i read
I am confused.
Configuration: I have two devices in the same network. They may not be in the same Subnet, but always in the same physical network (beyond the same router or switch etc.)
I want to communicate across IP multicast either 224.x.x.x or 239.x.x.x may be more fitting because we want it local, not beyond or forward through the router.
Can one machine be the receiver and the other machine sender of the same multicast address? and can the receiving machine send an answer to the sending machine?