Although the Bandwidth Broker has been proposed with the objective to give more intelligence to DiffServ networks, allowing the allocation of resources in a dynamic way for applications, once the resources are granted they remain statically allocated along the requested period. In this article, we propose an enhanced resource allocation mechanism, based on the fact that the instantaneous traffic load of the applications are generally dynamic in nature, and consequently, the required bandwidth is less than the allocated bandwidth during some periods. Simulation results demonstrate that the proposed mechanism yields better resource utilization while respecting limits of drop of packets and end-to-end delay.