Fast then inefficient? Engineering the traffic in edge-server relay network

Cloud services and other online applications are having imperative requirements on wide service coverage, fast content delivery and more importantly low monetary investment. To this end, online relay networks that consist of widespread free edge-servers (edge-ORN for short) are emerging to compete with traditional Content Delivery Networks (CDNs). With an ever-increasing amount of traffic, edge-ORN is now in urgent need of high-effective traffic engineering (TE) solutions. This paper presents a first TE study for this new type of network. In specific, we develop a lightweight TE method which jointly optimizes user-perceived latency and inter-autonomous system traffic. Three major contributions are made: 1) determine the right TE scheme for edge-ORN scenario; 2) correctly formulate and model the TE problem; 3) develop a fast yet efficient algorithm to solve the model, making it applicable to large-scale edge-ORNs. Experiments on a real-world trace show that, our method significantly outperforms other TE methods, achieving near-optimal TE effect. Furthermore, the method takes short computation time, which is of essential importance for edge-ORNs performing timely TE.