On Wide Area Network Optimization

Applications, deployed over a wide area network (WAN) which may connect across metropolitan, regional or national boundaries, suffer performance degradation owing to unavoidable natural characteristics of WANs such as high latency and high packet loss rate. WAN optimization, also known as WAN acceleration, aims to accelerate a broad range of applications and protocols over a WAN. In this paper, we provide a survey on the state of the art of WAN optimization or WAN acceleration techniques, and illustrate how these acceleration techniques can improve application performance, mitigate the impact of latency and loss, and minimize bandwidth consumption. We begin by reviewing the obstacles in efficiently delivering applications over a WAN. Furthermore, we provide a comprehensive survey of the most recent content delivery acceleration techniques in WANs from the networking and optimization point of view. Finally, we discuss major WAN optimization techniques which have been incorporated in widely deployed WAN acceleration products - multiple optimization techniques are leveraged by a single WAN accelerator to improve application performance in general.