Current resource reservation architectures for multimedia networks do not scale well for a large number of flows. We propose a new architecture that automatically aggregates flows on each link in the network. Therefore, the network has no knowledge of individual flows. There is no explicit signalling protocol, and the protocol overhead mainly consists in the introduction of a packet type with three values (reserved, request or best-effort) which can be encoded on two bits. Keywords: Resource reservation, Internet, Scalability, Bandwidth estimation