This invention is to cope with users requesting the delivery of stream data, flexibly. In this invention, a user terminal requesting the delivery of the stream data is used as a node in a delivery tree whose root is a delivery source device connected to a camera, and relays the stream data to a lower...http://www.google.com/patents/US8014398?utm_source=gb-gplus-sharePatent US8014398 - Method and apparatus for managing delivery of stream data
