Deterministic edge-to-edge delay bounds for a flow in a DiffServ network domain

It is important to understand delay bounds of an individual flow in the Internet in order to provide real-time applications such as Voice over IP (VoIP). In this paper, we study the deterministic bounds on edge-to-edge delay of a flow in a Differentiated Service (DiffServ) network domain with FIFO aggregation and class-based Guaranteed-Rate (GR) scheduler which provides guaranteed performance with rate reservation for a traffic class. We derive edge-to-edge delay bounds of a flow as a function of service rate allocated for a traffic class and leaky-bucket parameters adopted for flows at the network ingress, and information about joining and leaving flows. The resulting bounds are less than previously derived delay bounds, especially in the case where the burstiness of aggregated traffic is high and the edge-to-edge path is long.