With the popularity of cloud computing continuing to grow, organizations are looking to implement their own strategy to drive greater efficiency across their organization. For companies who are just starting out in the cloud, it can be a daunting process. The application development/test lifecycle is a great initiation point for many enterprises whose goal is to use cloud computing to simplify the process of building, testing, and deploying applications. In order to begin one's cloud implementation, it's helpful to look at cloud computing from two different points of view: an "inside-out" technology-centric view and an "outside-in" business-centric view.
Application Development in the Cloud Converges
From a technical perspective, cloud computing is the convergence of several pervasive technologies combining to simplify, standardize, and automate much of the IT infrastructure. At its core, cloud computing relies on virtualization, but is much more than just a virtualized data center.
Cloud computing includes an automated, self-service interface where users obtain services from standardized catalogs of resources such as virtual machine images. Generally, this is coupled with metering and billing systems allowing chargebacks based on the computing resources consumed per unit time (such as virtual-machine hours, GB of storage, or database transactions). The ease with which these resources can be provisioned and deprovisioned gives rise to the "elastic" nature of cloud computing. The billing mechanisms give users an incentive to deprovision unused resources; without that, cloud computing would be referred to as "expansive" rather than "elastic."
From a business perspective, cloud computing is simply the delivery of IT-related services across the network (LAN or Internet) a consumption-based charge model. This includes:
- Infrastructure as a service (IaaS, such as virtual machines, network connectivity, and storage)
- Platform as a service (PaaS, including the runtime stack including middleware and databases)
- Software as a service (SaaS, including applications such as email and office productivity tools)
- Business Processes as a service (BPaaS, such as financial transaction processing)
A key characteristic is that customers often pay for the services they consume but are not aware of the technology behind these services. For example, a SaaS consumer of email services might pay for a number of email accounts but they neither know or care about what operating system the underlying systems are running, or whether they are x86 virtual machines on KVM or Power System virtual machines on an IBM PowerVM.
Regardless of which view of cloud computing an organization prefers, these services can be delivered through a mixture of owned or leased infrastructure, hosted on or off premises. The services can also be delivered by a third party cloud service provider or by a customer's internal IT organization as well as run on infrastructure shared among several customers or dedicated to one customer. Additionally, the infrastructure has the ability to be housed on-premises or located off-site in a shared data center. These options are often referred to as being on a spectrum from "public" to "private" clouds, with the expected tradeoffs among privacy, control, and cost.
Whether viewed from the technology-out or the consumption-model in, or delivered via dedicated or shared infrastructure, cloud computing can help drive significant increases in efficiency across an IT organization. However, many organizations are still unclear about where to start applying cloud computing. Many companies realize that somewhere between the hype and the FUD (fear, uncertainty and doubt), there must be an alternative. Application development/test lifecycle offers that alternative since infrastructure utilization is low, the labor costs are high, and the lifecycle is highly automatable. Cloud computing can streamline the development lifecycle dramatically, reducing cost, improving quality, and reducing time-to-market.