RMCP is a protocol which is used to realize a relayed multicast data transport scheme. Differently from the conventional IP multicast, RMCP can configure a relayed multicast path that multicast traffic flows by using intermediate end-hosts. RMCP can be applied to the current unicast based Internet where IP multicast has not been deployed completely without any modifications. This Recommendation | International Standard addresses the basic concepts needed to specify RMCP for relayed multicast. It defines the related terminology and proposes a framework for the future development of RMCP. The framework covers network topology including network entities and the relationship between them, service scenarios, basic operations, and message encoding rules.