Nash Equilibrium and Decentralized Pricing for QoS Aware Service Composition in Cloud Computing Environments

QoS aware service composition necessitates an effective pricing mechanism in regulating service providers in public cloud computing environments. However, due to the fact that service providers are usually autonomous, strategic and self-motivated, it is far from trivial to deal with the pricing issues between them. In this paper we formulate a non-cooperative service pricing game to understand the performance of a QoS aware service composition model, for which multiple providers strategically bid how to provide and price their elementary services and establish the Nash equilibrium as the final service composition scheme. We also develop a proportional revenue division rule to incentivize elementary service providers to contribute in improving the QoS of the final composite service delivered to end users. Concerning privacy conservation, we develop a decentralized and recursive bidding algorithm, allowing service providers to reach an equilibrium without disclosing their private information. Through theoretical analysis, we show that a Nash equilibrium exists in a QoS aware service composition game. Through extensive simulations, we show that the proposed recursive bidding process can converge quickly to a Nash equilibrium service composition scheme, and its efficiency is generally high.