Interoperability is defined by the European Commission (EC) as an extensive concept that embraces the capability of entities to exchange data and information work together for their common goals.
“‘interoperability’ means the ability of disparate and diverse organizations to interact towards mutually beneficial and agreed common goals, involving the sharing of information and knowledge between the organizations, through the business processes they support, by means of the exchange of data between their respective ICT systems.” (European Commission 2009)
This is the definition of interoperability of the European Commission (EC).
In the literature there are many definitions of Cloud Computing interoperability.
Under consideration of the vendor lock problem that was explained in the problem statement, the definition “interoperability refers to costumers’ ability to use the same artifacts, such as management tools, virtual server images, and so on, with a variety of Cloud Computing providers and platforms” (Sambyal, Jamwal und Sambyal 2010) seems to be very adequate.
One of the most detailed definitions that clarify the terms “Cloud Computing interoperability, portability and compatibility” is the one of Reuven Cohen. He describes that Cloud Computing interoperability focuses on the ability to cooperate across various cloud platforms. The aim of cloud interoperability is to simplify the utilization of various cloud providers due to their common set of application interfaces.
Compatibility and portability are describing how interoperability can be achieved. So these two terms can be seen as subsets of interoperability. Cloud Compatibility implies that data and applications are processed identically irrespective of the cloud provider. Cloud Portability refers to the ability that application components can be simply transferred without any restrictions regarding cloud providers or platforms (Cohen 2009).