A Contract-Ruled Economic Model for QoS Guarantee in Mobile Peer-to-Peer Streaming Services

Current commercial mobile streaming applications call for innovative technologies for stable QoS guarantee. In this paper, we provide a comprehensive treatment of QoS guarantee through a contract-ruled approach. In particular, we envision a peer-assisted mobile peer-to-peer streaming system as a QoS trading market, where all parties involved in the system, i.e., Service Provider (SP), End User (EU), and Assisting Peers (APs), are real economic entities that are organized with contractual constraints to achieve a stable and guaranteed QoS output. The QoS trading in the market is divided into two parts. One is a basic contract that establishes the business agreement between an interested EU and a SP. We propose a QoS contingent payment to mitigate the EU's concern on the uncertainty of QoS delivery and derive an optimal contract that achieves Pareto efficiency. The other is a subcontract, in which we model transactions between the SP and contracted peers as a principal multi-agents problem, that achieves a desired joint QoS output. We further design a sharing scheme with team penalty that could overcome the free-riding problem existed in the subcontract and show that the Pareto efficiency can be achieved by setting a proper team penalty. Both numerical evaluations and prototype experiments demonstrate the effectiveness of our proposed scheme.