Level No. 1: Virtualization
Virtualization of applications and infrastructure is the foundation for cloud computing. Today, much of the visibility around virtualization relates to the hypervisor, which allows server infrastructure to be carved up and more effectively utilized by application workloads.
The other side of virtualization is about delivering applications as coordinated sets of virtual images. These self-contained units consist of the application, database, middleware and other components, packaged together with necessary operating system bits-known as just enough operating system (JeOS). Virtual images enable applications to be deployed on any hypervisor and moved seamlessly from one virtual server to another.
This approach essentially eliminates the barriers to application deployment, including manual configuration, and tuning and certification of application workloads with underlying systems. Maintaining and updating deployed applications also become easier and faster. All this speed and flexibility adds up to dramatically faster deployments, which allow organizations to more rapidly realize application value and increase business responsiveness.
Level No. 2: Cloud experimentation
While cloud computing is the next logical step beyond virtualization, it can't happen without a plan based on real experience. Smaller steps are needed to be taken in order to build knowledge, gain understanding and amass experience. So the next step of the cloud adoption model involves usage, experimentation and laying the groundwork for further cloud initiatives.
Amazon Elastic Compute Cloud (EC2) is a good example of a mature and stable cloud infrastructure that offers a low barrier to usage-swipe a credit card and you've entered the cloud. At this stage in cloud adoption, we recommend establishing an EC2 account and running a non-mission-critical application in the cloud. The team needs to build a base of experience in cloud infrastructure, processes and operations.
It's also a good idea to get application architects involved in thinking about the reference architecture for cloud computing so that future applications are designed with cloud deployment in mind. Strong executive sponsorship needs to come online at this point to ensure proper funding is available and a realistic timeline is established.