The expectation of a global presence of services leads to the need for large numbers of service instances allocated in a multitude of regional data centers in order to provide sufficient service capacity close to where the demand occurs. Scale of service instances is anticipated growing ≫104 raising new challenges for control and management. Pragmatically, it must become much easier to deploy service instances in data center, allocating resources, sharing them, installing and configuring data and software needed for service instances and integrating them into a singular service that appears to a consumer. Adjusting numbers and locations of service instances is seen as a basic control mechanism in order to follow regional or temporal fluctuations in demands. A virtualization layer takes care of resource allocation from different data center locations and all specifics when service instances are allocated in a particular data center. Virtualized data centers provide a consistent operating environment spanning multiple physical data center locations for the whole family of service instances. And vice versa, physical data centers host several execution environments for different services.
Developing information systems for the office environment of today requires powerful representation formalisms and techniques capable of modelling all office elements. Furthermore, these formalisms should provide appropriate facilities for the validation of a conceptual schema. It is argued that an office modelling approach should provide semantic account for the various aspects of the schema, as well as facilities for simulating its behaviour. A conceptual modelling language is presented that combines the object oriented and logic programming paradigms, and it is demonstrated how this language can be used to validate the conceptual design of an office information system
