Bump = Short roll. When you're bumping a dog you're not evaluating the dog, you'd do it to get one started or let one get the feel of actual contact.

Roll = well, a roll This is where the fun begins, because it's here you're evaluating your dog, schooling him, seeing if he's got what it takes to be a show dog, or not . It's here where he will show you what style he is, or how game he is if you want to check it. A roll is essentially a sparring session, there is no set time limit and you're free to pick your dog up whenever you want.