This is the first in a series of four articles discussing infrastructure as a service (IaaS) clouds. The articles will start with basic level setting and will dive progressively deeper as the series progresses. The topics for the series will be:
- What is cloud
- What value should cloud provide
- Public, private, and hybrid cloud
- Starting on a cloud project
- Application taxonomy, what belongs in the cloud, and why
- What you should look for in cloud infrastructure software
- Evaluating different approaches to cloud infrastructure software
What Is Cloud?
Cloud is fundamentally about creating a dynamic computing infrastructure that enables end users to service and manage themselves in a process that is frictionless and instantaneous, but also secure and controlled. Resources are allocated in a very fine-grained fashion and can be relinquished at any time. Usage and chargeback is measured per customer, per resource utilization, and per unit of time, not by physical piece of equipment.
Cloud is not an incremental step on top of virtualization. While virtualization is a key enabler of cloud, the motivation, focus, target applications, and evaluation criteria are very different.
For clouds to be useful and cost effective, they must also have the properties of being very scalable and smooth to manage at the infrastructure level. The idea is to remove as much as possible from the day-to-day operations from the datacenter IT team and to scale that group’s reach and efficiency. The primary responsibility of the datacenter managers should be scaling the cloud in response to growth in demand. They should be able to look at utilization in aggregate and plan and deploy space, power, networking, and servers in as much of a just in time manner as possible. They should no longer need to focus on project specific deployment activity – that is handled by a combination of the end users’ self-service activities and automated responses from the cloud itself.
Private clouds represent the transformation of an IT datacenter into a large self-service pool of resources for internal customers to use. Public clouds open up that service to external organizations to purchase. Hybrid cloud refers to when one organization uses a private cloud for some of its work and a public cloud for other work; and where there is continuity between the public and private cloud utilization. In hybrid clouds, identity, policy and user interface are common, thereby blurring the distinction between public and private to the end user. This series discusses cloud in general with public, private and hybrid being implementation decisions for specific projects. We will introduce distinctions between these cloud types only where necessary.
Cloud Business Value
The end result of cloud to the business is two-fold. Primarily, cloud enables end users to service their own IT needs in a frictionless manner, making the business much more agile - as business units and individuals can innovate quickly and execute on new ideas immediately before they become stale. A secondary but still crucial benefit is that the cost of IT and its value become intimately tied together with a high degree of transparency. Costs are minimized and associated with end user organizations and business units. Let’s dive into the cost analysis in a bit more detail.