scenario {
	component "System"
	actor "SA 3"
	actor "SA 2"
	par "123" over "SA 3" "SA 2" {
		"SA 3" -> "SA 2" : "c1"
	} "456" {
		"SA 3" -> "SA 2" : "c2"
		"SA 2" -> "SA 3" withReturn : "cr2"
	}
	opt "123" over "SA 3" "SA 2" {
		"SA 3" -> "SA 2" : "c3"
	}
}