Defining a Measure of Cloud Computing Elasticity

Cloud computing has gathered great attention recently as a method for eliminating or at least reducing expensive setup and maintenance cost of computing resources. Cloud computing has many key characteristics such as reliability, multi-tenancy and rapid elasticity. However, these characteristics suffer from the lack of clear and quantitative measures. In this paper, we provide a preliminary work that can help in providing a set of benchmarks for a cloud computing performance. More specifically, we provide an approach for measuring the elasticity of a cloud. Elasticity of a cloud computing system refers to its ability to expand and contract overtime in response to users' demands. The work presented in this paper is inspired by the definition of elasticity that is used in physics. This definition is adopted to represent the basic features of a cloud computing environment and its parameters that are related to elasticity. Case study shows the adoption methodology and highlights some of the basic parameters affecting elasticity as measured by the proposed approach.