Multiple combinations of hardware and network components can be selected to design an Information Technology (IT) infrastructure that satisfies requirements. This paper proposes depreciation a framework which helps to create an efficient virtual infrastructure and keep it up-to-date. The framework monitors changes in configuration of the virtual infrastructure and uses gathered data for generating infrastructure optimization recommendations. The ontology, which classifies virtual machines is the key part of the proposed framework. The structure of this ontology is outlined in the paper and an application example is presented