Cloud is a metaphor for remote computing using the Internet as the connecting network. Cloud services vendors offer utility based computing services to their customers. Customers signing up for accounts with Cloud service providers are generally looking for “on demand” scalability of IT infrastructure and applications and “pay as you go” payment options.
What are the Characteristics of the Cloud?
- The Cloud offers on demand self service. What does that mean? It simply means that the user can demand and get more storage space or an access to a business application on demand.
- The Cloud is ubiquitous. Cloud storage and Cloud based applications can be access over the Internet. The user has to have an Internet connection and a computer to access the Cloud. This can be done from anywhere in the world and hence it is ubiquitous.
- The Cloud offers independent resource pooling. This means that multiple organizations or users can share resources that are available with the Cloud service vendor.
- Rapid elasticity. This harks back to “on demand” service. Users can scale up or scale down the use of resources or applications in accordance with the level of computing requirements of the organization at different points in time.
- The Cloud offers measured service. The economic model used by Cloud service providers is the pay-as-you-go. To this end they need to measure the amount of space or the number of application instances consumed by the user. The data is made available to the user for billing and monitoring purposes. Hence, measured service is a characteristic of Cloud services.
What are the Services offered in the Cloud?
- Everything as a Service (EaaS) includes: Integration as a Service, Security as a Service, and Governance as a Service. These services are particularly intended for the MSPs (managed service providers). The development was sparked by a need to accelerate Cloud development and deployments.
- Software as a Service (SaaS) focuses upon delivering application software as a service to end users. This concept evolved from web deployments of the pre-Cloud service era and the success of websites like salesforce.com. SaaS offers the end user innovative integration options, increased stability, improved SLA and a range of applications that were erstwhile unaffordable.
- Platform as a Service (PaaS) includes: Data as a Service, Database as a Service, and Infrastructure as a Service. This type of service emerged from the hosting concept of the pre-Cloud service era. It was sparked by virtualization. The service opens up to the user Operating System options, better pricing (utility based billing), and granular feature sets for control and dynamic provisioning of hardware.