Effective bandwidths is a statistical descriptor in the context of stochastic models for statistical sharing of resources. It is generally known [1] that effective bandwidths assigned to independent flows beeing multiplexed behave additively. Furthermore it has been shown [2] that under the many sources limiting regime, an effective bandwidth assigned to a flow passing through a switch is not changed, and inductively a flow has the same effective bandwidth through the entire network. If all flows feeding a network under consideration have well defined effective bandwidths and QoS demands, resource dimensioning can be done based on simple large deviation principles. We address the problem of specifying and limiting effective bandwidths of arriving flows by introducing a new shaping and policing algorithm based on an on-line effective bandwidth estimator. The presented algorithm's functionality is veryfied by both synthetic and real data traces. Finally the performance of proposed algorithm variants is discussed.

Abstract—Effective bandwidth is a descriptor in the context of stochastic models for statistical sharing of resources. One of the most interesting properties of effective bandwidth is that it does not change when passing a network node under many sources limiting regime (infinitely many sources). This is called “invariance property ” of effective bandwidth. Numerical simulations have suggested that in some cases, the “invariance property ” of effective bandwidths holds already for a surprisingly small number of competing flows even in the presence of aggressive TCP traffic. The real question, though, is: how many input processes are needed for reasonable convergence over the scale of interest? This work addresses this question using recent results from the large deviations theory under many sources limiting regime and the theory of statistical network calculus. The advantage of predefining the minimum number of independent multiplexing flows at each network node to observe approximate invariance of effective bandwidth is that the task of network resources dimensioning can be greatly simplified. I.