In this paper we propose a framework for a simple resource reservation protocol for multicast communications in the Internet. In contrast to RSVP, where heavy setup mechanisms are used, our protocol is traffic driven and does not use special messages for resource reservation, refresh or release. The reservation session is managed by the flow data packets themselves. Our protocol is suitable for resource reservation in dynamic and rearrangeable multicast environments. It also tolerates nodes and links failures by instantaneously allowing a new resource reservation on alternative paths.