On scalable design of bandwidth brokers

lit this paper we study the scalability issue in the design of a centralize d bandwidth broker model for dynamic control and management of QoS provisio ning. We propose and develop a path-oriented. quota-based dynamic bandwidth allocation mechanism for efficient admission control operations under the centralized bandwidth broker model. We demonstrate that this dynamic bandwi dth allocation mechanism can significantly reduce the overall number of QoS state accesses/updates. thereby increasing the overall call processing cap ability of the bandwidth broker. Based on the proposed dynamic bandwidth al location mechanism, we also extend the centralized architecture With a sing le bandwidth broker to a hierarch ic ally distributed architecture with mul tiple bandwidth brokers to further improve its scalability. Our study demon strates that the bandwidth broker architecture can be designed in such a ma nner that it scales with the increase in the network capacity.