Modeling and testing of cloud applications

What is a cloud application precisely? In this paper, we formulate a computing cloud as a kind of graph, a computing resource such as services or intellectual property access rights as an attribute of a graph node, and the use of a resource as a predicate on an edge of the graph. We also propose to model cloud computation semantically as a set of paths in a subgraph of the cloud such that every edge contains a predicate that is evaluated to be true. Finally, we present algorithms to compose cloud computations and a family of model-based testing criteria to support the testing of cloud applications.

I. Introduction

Cloud computing [8][16] is an emerging trend to deploy and maintain software and is being adopted by the industry such as Google [14], IBM [7], Microsoft [26], and Amazon [1]. Several prototype applications and platforms, such as the IBM “Blue Cloud” infrastructure [7], the Google App Engine [15], the Amazon Cloud [1], and the Elastic Computing Platform [11], have been proposed. However, when it comes to the question on how to model cloud applications (e.g., [9][30]), the question remains unexplored. In our previous work [21][25], we put forward several issues toward developing cloud applications. In this paper, we sketch an application model, and develop theoretical test adequacy criteria for testing applications in a cloud.