Beyond best effort: Choosing connectivity portfolio for cloud brokering platform by risk/profit tradeoff

We utilize portfolio theory of finance and investment science in order to show how a cloud broker can select a portfolio of connectivities in order to accommodate requirements for cloud services of users, who need better than the best effort Quality of Service (QoS). Following economic theory, we assume that cloud broker makes his decision by choosing appropriate tradeoff between profit and risk. The risk has two sources: uncertain demand and uncertain connectivity quality. Using Internet traffic data we show that it is possible to deliver considerably higher QoS by selection of connectivity portfolios that combine the best effort connectivity of different grades with premium grade connectivity.