How to broadcast obstacle detection to other robots in group?

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I currently have a package that has multiple robots moving at constant velocity, with obstacle avoidance behaviors. What would be the best way to modify this package such that each of the robots broadcasts information to the other the other robots wirelessly? All robots should constantly broadcast the value of 0 if they detect no obstacle, and 1 if they detect an obstacle using sonar. They should all then exhibit the same obstacle-avoidance behaviors; that is, all robots should turn through the same angle at the same speed, until the robot that had originally detected the obstacle no longer detects it and goes back to broadcasting the value 0.