Understanding the Types of Cloud and Cloud Services
Today’s organizations want the freedom to focus on the application or service rather than all the individual operating system instances running inside virtual machines. Business units and users need to be able to provision their own virtual environment, or private cloud, within the structure predefined by the IT group, using simple self-service portals. This shift is the next step in the IT journey—from physical to virtual and now to private cloud.
CROSSREF This shift to the private cloud is covered in detail in Chapter 10.
The private cloud builds on virtualization but focuses on providing services to businesses in a highly scalable but manageable manner with infrastructure components taking care of the creation and maintenance of the underlying virtual machines and operating systems. The private cloud enables a company to focus on the service being provided, which could be a multi-tiered service consisting of numerous web servers interacting with clients, then a middleware tier performing processing, then a back-end database tier. With a private cloud, a complete instance of the entire service can be deployed with the click of a button; and the actual servicing of the environment is transparent to the operation of the service. If certain aspects of the service are becoming highly utilized, then that tier can easily be scaled out by merely requesting additional instances of that tier; the infrastructure handles all the work ...