Scalability is one of the key properties that determine the successfulness of a scheme working in a large system at the Internet scale.

We address the scalability issue in supporting QoS over the Internet from two supplementary aspects, namely the packet forwarding data plane and the network resource management control plane.

On the data plane, we propose a Virtual Time Reference System (VTRS) is a unifying packet scheduling framework to support per-flow rate/delay service guarantees.

On the control plane, we propose and develop a hierarchical multiple bandwidth broker architecture to overcome the inherent scalability problem associated with the centralized bandwidth broker system.