Measurement-Based Modeling of NGN Access Networks from an Application Perspective

One aspect highly neglected so far in Next Generation Networks development is that their access-agnostic service architecture requires NGN services to provide adequate user perception for a broad range of underlying access network technologies. Automated service testing for a wide variety of access technologies will therefore become indispensable in the near future. In this paper we introduce a three-step process for access network modeling based on the IETF IP Performance Metric framework. Starting with the selection of metric and methodology, measurements in existing access networks allow acquiring the respective parameters, which are finally used as an input for access network emulators or simulators. We illustrate our approach with metric selection and measurement results for public GPRS and HSDPA networks. A modified Open-Source WAN Emulator which uses these measurements results as input can accurately model "typical" access links at IP-layer level, both from a signaling and a media perspective.