This paper describes and tests a distributed bandwidth broker that has been implemented in NS simulator. It focuses on the admission control algorithm, its advantages and drawbacks. Also, the bandwidth broker is tested, managing the IP Premium service and we compare 2 different implementations of the service. Finally it approaches the problem of the optimal location of a bandwidth broker in a backbone network. For this purpose, a new model is proposed that evaluates each node and finally selects the most capable node where the base bandwidth broker should be located.