In cloud computing,
as files, databases, applications, and virtual machines may either scale or move from one machine to another in response to load increases and decreases (
). We study a type-based technique for analysing the deployments of resources in cloud computing. In particular, we design a type system for a concurrent object-oriented language with dynamic resource creations and movements. The type of a program is
, namely it expresses the resource deployments over periods of (logical) time. Our technique admits the inference of types and may underlie the optimisation of the costs and consumption of resources.