Cloud computing underpins an important part of economic activity today, and has the potential to make a major contribution to future growth.
To deliver its anticipated benefits, it must be easy to use and cost-efficient. This means that enterprises and individuals must be able to use cloud products and services as far as possible “off the shelf”. The products and services should work together, and minimal effort should be needed to incorporate them into a user’s systems.
This is the case for the basic Internet, but not yet for the additional components that constitute the cloud. Lack of portability of and interoperability between these components could mean that the potential of cloud computing is not fulfilled.
This guide analyzes cloud computing portability and interoperability. It makes recommendations to customers on how best to achieve portability and interoperability when working with current cloud products and services. It makes recommendations to suppliers and standards bodies on how standards and best practice should evolve to enable greater portability and interoperability in the future.
Following this summary, the Guide starts with two introductory chapters. Problem Statement discusses the problem, and Cloud Computing explains the basic concepts of cloud computing. The analysis then proceeds by distinguishing the important categories of Cloud Portability and Interoperability.
The central part of the analysis is the definition of the Distributed Computing Reference Model. Portability and interoperability reduce cost and effort because they allow enterprises to use products and services that work together “off the shelf”. The model identifies the major components of cloud-enabled solutions that can be implemented by such products and services.
A high level of portability and interoperability, such as we have for the Internet, is achieved when products and services conform to interface standards. The Guide describes the Portability and Interoperability Interfaces, and reviews the state of development of their standards.
Interface standards can apply to generic components, such as platforms and infrastructure, but applications have interfaces that reflect their particular functionality, and are not appropriate for standardization. The Guide puts forward a set of Application Design Principles to minimize their cost of integration.
The final chapter of the Guide contains Conclusions and Recommendations for how enterprises should proceed in the light of the current state of standardization, and for how standards bodies and the industry should work to develop standards and best practices that will improve portability and interoperability for the future.
Cloud Computing and SOA explains the relation of The Open Group SOA Reference Architecture [SOARA] to the Distributed Computing Reference Model.
Example Use-Cases for WS-I and Raw HTTP contains two small example use-cases illustrating the differences between the two main web service interface styles: WS-I and Raw HTTP.
The final section is a list of acronyms used in this Guide.