The Connection Dependent Threshold Model for Finite Sources – A Generalization of the Engset Multirate Loss Model

Abstract

Abstract. Call Blocking Probabilities (CBP) are the key index of the call-level QoS in multirate networks supporting either CBR or elastic traffic. We review the Engset Multirate Loss Model, in a single link, for CBR traffic, and for elastic traffic we propose the Connection Dependent Threshold Model with finite sources (f-CDTM). In f-CDTM, calls may adjust their traffic and bandwidth requirements according to sets of thresholds. Furthermore, we present the f-CDTM for a mixture of service-classes of finite and infinite sources. The proposed models don't have a product form solution; therefore the CBP calculation is based on approximate but recursive formulas used for the link occupancy distribution determination. The latter is complex since it requires enumeration and processing of the system state space. Simulation results validate our analysis.