A Semi-Markov Decision Model-based brokering mechanism for mobile cloud market

As the multitude and complexity of the cloud market increases, the evaluation and selection of cloud services becomes a burdensome task for the users. With the extraordinary rise of available services from various Cloud Service Providers (CSPs), the role of cloud brokers has become more and more important. This paper proposes an optimal cloud broker model to address the challenge of optimally allocating multiple cloud system resources to multiple mobile user's requests with different requirements. The cloud brokering mechanism is formulated as a Semi-Markov Decision Process (SMDP) model under the average system cost criteria. The overall system cost takes into consideration the cost of occupying computing resources, the communication costs, the request traffic, as well as various security risk degrees and resource requirements from the various mobile users. Through minimizing the overall system cost, the optimal resource allocation policy is calculated by means of the Value Iteration Algorithm. Some analysis are conducted and numerical results are presented, demonstrating the feasibility of the proposed cloud broker design.

I. Introduction

Mobile cloud computing (MCC) is a service model where resource-hungry mobile applications are offloading their computational tasks from resource-constrained devices to powerful cloud data centers in order to satisfy their immediate need for CPU cycles. In a traditional MCC design, a mobile device wirelessly offloads its computation task to a resourceful remote cloud data center or a cloudlet attached to a base station (BS).