Performance evaluation of a next generation network prototype using WiMax as an access network

The emergence of the Internet Protocol (IP) has resulted in the evolution of telecommunication networks to All-IP technologies known as Next Generation Networks (NGN). These networks consist of heterogeneous network technologies that are interconnected to provide end-to-end services to customers. This network evolution has been accompanied by the emergence of broadband real-time applications. End-to-end successful delivery of these applications requires that the networks meet certain performance specifications. Individual technologies have been designed to meet these specifications. Worldwide Interoperability for Microwave Access (WiMax) is one of the technologies designed to meet the demands of the applications. One of the challenges faced by network operators is to provide consistent Quality of Service (QoS) to the applications as they traverse the different transport technologies. In this paper, we propose a QoS system based on the use of DiffServ and the concept of class-of-service mapping to address this problem. To evaluate the proposed QoS architecture, we implement a NGN prototype using a WiMax access network and an IP core network based on Linux routers. The results obtained show that the network conforms to ITU-T performance standards and can deliver integrated NGN services. However, the quality of real-time video services depends on the codec of the video application.

I. Introduction

Traditional telecommunication networks were designed to carry fixed telephone, data, mobile telephone and internet services separately. Transport and service networks were supplied by a single vendor and interoperability was limited to interconnection gateways. The emergence of IP has resulted in the evolution of these networks to NGN. The International Telecommunication Union Telecommunications Standardization Sector (ITU-T) has defined the NGN as a packet-based All-IP network capable of making use of multiple broadband, QoS-enabled transport network technologies [1].