With the growing popularity of Cloud Computing, it is important to make sure that everyone has a common understanding of the subject. A new article by Dave Malcolm "The Five Pillars of Cloud Computing" is trying to do this by examining 5 core principles of Cloud Computing.
... a set of Microsoft-hosted, highly scalable, developer-oriented services that provide key building blocks required by many cloud-based and cloud-aware applications. Much like the .NET Framework provides higher-level class libraries that make developers more productive, .NET Services can help developers focus on their application logic rather than building and deploying their own cloud-based infrastructure services.
Dynamic Computing Infrastructure is the foundation of Cloud Computing which should be based on a standardized, scalable, and secure physical infrastructure providing levels of redundancy and virtualization.
A dynamic computing infrastructure is critical to effectively supporting the elastic nature of service provisioning and de-provisioning as requested by users while maintaining high levels of reliability and security. The consolidation provided by virtualization, coupled with provisioning automation, creates a high level of utilization and reuse, ultimately yielding a very effective use of capital equipment
IT Service-Centric Approach, providing support for running some business/IT services or applications for a specific, timely purpose. It should abstract the server-centric view of the infrastructure, and provide users with an easy access to powerful pre-defined computing environments suitable for the execution of their services.
An IT Service Centric approach enables user adoption and business agility - the easier and faster a user can perform an administrative task the more expedient the business moves, reducing costs or driving revenue.
Self-Service Based Usage Model providing users the ability to upload, build, deploy, schedule, manage, and report on their business services on demand.
The benefit of self service from the users' perspective is a level of empowerment and independence that yields significant business agility. One benefit often overlooked from the service provider's or IT team's perspective is that the more self service that can be delegated to users, the less administrative involvement is necessary.
Minimally or Self-Managed Platform enabled through software automation, leveraging a provisioning engine for deploying services and tearing them down; mechanisms for scheduling and reserving resource capacity; configuration, management, and reporting support, ensuring effective resources allocation/reallocation for multiple groups of users; access control policies for resource utilization.
...these capabilities enable business agility while simultaneously enacting critical and necessary administrative control. This balance of control and delegation maintains security and uptime, minimizes the level of IT administrative effort, and keeps operating expenses low, freeing up resources to focus on higher value projects.
Consumption-Based Billing ensuring that consumers pay only for resources they use - are charged or billed on a consumption-based model.
The value here from a user's perspective is the ability for them to pay only for the resources they use, ultimately helping them keep their costs down. From a provider's perspective, it allows them to track usage for charge back and billing purposes.
The support for all of the above principles is required for producing a cloud (private or public) providing a compelling business value including (but not limited to) savings on capital equipment and operating costs, reduced support costs, and increased business agility.