If you have configured the RTI to be used on two computers, you can then start the blue database on one and the red database on the other.
Then, start both simulations.
Creating (or removing) one entity in either blue or red vsTASKER will distribute the Entity (as external) on the other.
Finally, relocate any local Entity to the map and see how it moves on the other.
Once both simulations are running, check that clicking on the map of one vsTASKER will draw a red circle on both.
