Capacity planning strategies for voice-over-IP traffic in the core network

This paper examines different strategies for capacity planning within a core IP network that is used to transport real-time voice traffic. First, a "trunking" scenario is studied, in which traffic pipes are established between each pair of PSTN gateways, either along shortest paths or traffic-engineered paths. Secondly, a capacity provisioning approach is put forward, that supports the worst-case voice traffic load on each IP link. Simulations show that traffic engineering offers a substantial reduction of the maximum link load in the network. Moreover, it is shown that when the worst-case provisioning approach is followed, admission control and adaptations to the traffic matrix are not needed, at the cost of provisioning a higher amount of network resources.