Algorithms for IP network design with end-to-end QoS constraints

The new generation of packet-switching networks is expected to support a wide range of communication-intensive realtime multimedia applications. A key issue in the area is how to devise reasonable packet-switching network design methodologies that allow the choice of the most adequate set of network resources for the delivery of a given mix of services with the desired level of end-to-end Quality of Service (e2e QoS) and, at the same time, consider the traffic dynamics of todays packet-switching networks. In this paper, we focus on problems that arise when dealing with this subject, namely Buffer Assignment (BA), Capacity Assignment (CA), Flow and Capacity Assignment (FCA), Topology, Flow and Capacity Assignment (TCFA) problems. Our proposed approach maps the end-users performance constraints into transport-layer performance constraints first, and then into network-layer performance constraints. This mapping is then considered together with a refined TCP/IP traffic modeling technique, that is both simple and capable of producing accurate performance estimates, for general-topology packet-switching design networks subject to realistic traffic patterns. Subproblems are derived from a general design problem and a collection of heuristic algorithms are introduced for compute approximate solutions. We illustrate examples of network planning/dimensioning considering Virtual Private Networks (VPNs).