Cloud Computing is currently attracting the attention of the entire ICT world. Cloud Computing is not a new technology but a conceptual framework that employs technologies and architectural approaches like SOA usable in consolidated and combinable form. Clouds consist of cross-institutional resource pools such as hardware, design platforms and electronic services. These resources are virtualized and can be dynamically configured and can thus be flexibly adjusted and scaled to meet current demands. The access to these resources occurs remotely, e.g. over the Internet. Resource providers and users can thereby be organizationally separated. However, they can also be established in a joint organization such as in private Clouds.
There are currently many Cloud providers on the market. For the users of Cloud services in particular, it is important to avoid becoming dependent on a provider (so-called lock-in) and to have the opportunity to change providers. If a user wants to expand his or her service portfolio and therefore combine the services of different providers in so-called cross-Cloud-scenarios, these services must be able to seamlessly work together. Ensuring the required interoperability of services, platforms and infrastructures regarding aspects like interfaces, data, security, protocols or transactions poses a great challenge.
The SOA/Cloud Lab demonstrates the switch and entry into this promising technology with the help of various eGovernment applications. It is demonstrated, how interoperability problems in the heterogeneous service-provider-world can be solved and how economically risky dependencies on providers can be prevented.
Cloud Computing in the German public sector
The introduction of Cloud Computing in the German Public Sector depends on the solution of several technical, organizational and legal issues. Usage scenarios and associated use cases are methodological tools to understand and these issues and to provide suitable solutions within specific application contexts.
- For this purpose, Cloud Computing definitions and use cases such as those provided by the National Institute of Standards and Technology, the Distributed Management Task Force, and the Cloud Computing Use Case Discussion Group have been analyzed.
- A Cloud use case taxonomy has been derived from the results of this analysis.
- Following this taxonomy, typical usage scenarios are evaluated considering their applicability for the German Public Sector.
- These usage scenarios have been submitted to the ISO as examples on how to apply a scenario based definition and analysis methodology to identify standardization requirements.