Sparse mode and dense mode multicast

Question

What is the difference between sparse mode and dense mode multicast?

Answer 1

Dense mode multicast supposes all multicast neighbors want to obtain all multicast traffic except the neighbors encompass specifically pruned the traffic. Sparse mode multicast supposes multicast neighbors do not want to obtain multicast traffic unless they have request for it. Dense mode employs source-based delivery trees whereas sparse mode employs shared delivery trees where traffic is initially sent to an RP.