Required capacity for ATM Virtual Paths for QoS on cell and connection level

We show approximation formulae for required capacities (bit rates) of ATM Virtual Paths that cover allocation on cell and connection level at the same time. Such formulae are valuable for dimensioning and routing purposes, as they allow for fast and precise calculations of required capacities and show the kind of dependency on the traffic demand for given traffic characteristics and Qulity of Service requirements. We discuss how to determine the coefficients of the approximation and its precision for connections with on-/off characteristics (voice, data). Finally, we show the gain that might be obtained if statistical multiplexing of variable bit rate connections is taken into account at the cell level