Running Gazebo Ardupilot Plugin and Ardupilot SITL on Different Computers

I have just begun drone programming and started from using SITL as you guess. All example about gazebo and SITL runs on the same computer using localhost. I want to run them on different computers such that one computer’s IP address is and the other one’s
For example let gazebo run on and SITL run on

There is already a Discussion about this which is old and doesnt have valid answers.

Can anyone help me on this issue?