Activity Diagrams - send/receive notation


On the Activity diagram if something is sent and then received instantaneously will the notation for send and receive be different for if it is received say 5 hours later…?

If so, what is the difference?
i.e. I have been led to believe that the notation does differ… and that if it is instant you just use boxes, whereas if it is longer you use the box arrow for send and box (cut arrow) for receive - if you know what i mean!


The activity diagram is good for modeling the flow, but not specific for modeling time related stuff. I suggest you can use note and anchor to document the time dependent issues in your diagram.