Now that you have a basic understanding of what a cloud is and how it works, let’s enumerate and dive in to some of its most useful attributes and characteristics. After spending years talking about Amazon Web Services in public forums, I’ve found that characterization is often more effective than definition when it comes to con-veying the essence of the Amazon Web Services, and what it can do.
Here are some general characteristics of the Amazon Web Services.
The cloud allows scaling up and scaling down of resource usage on an as-needed basis. Elapsed time to increase or decrease usage is measured in seconds or minutes, rather than weeks or months.
Economies of scale
The cloud provider is able to exploit economies of scale and can procure real estate, power, cooling, bandwidth, and hardware at the best possible prices. Because the provider is supplying infrastructure as a commodity, it’s in its best interest to drive costs down over time. The provider is also able to employ dedicated staffers with the sometimes elusive skills needed to operate at world- scale.
This is a general characteristic rather than a business characteristic for one very good reason: with cloud-based services, technical people will now be making resource allocation decisions that have an immediate effect on resource con- sumption and the level of overall costs. Running the business efficiently becomes everyone’s job.
Here are some of the defining characteristics of the Amazon Web Services from a business-oriented point of view:
No up-front investment
Because cloud computing is built to satisfy usage on-demand for resources, there’s no need to make a large one-time investment before actual demand occurs.
Fixed costs become variable
Instead of making a commitment to use a particular number of resources for the length of a contract (often one or three years), cloud computing allows for re- source consumption to change in real time.
CAPEX becomes OPEX
Capital expenditures are made on a long-term basis and reflect a multi-year commitment to using a particular amount of resources. Operation expenditures are made based on actual use of the cloud-powered system and will change in real time.
Allocation is fine-grained
Cloud computing enables minimal usage amounts for both time and resources (for example: hours of server usage, bytes of storage).
The business gains flexibility
Because there’s no long-term commitment to resources, the business is able to respond rapidly to changes in volume or the type of business.
Business focus of provider
The cloud provider is in the business of providing the cloud for public use. As such, it has a strong incentive to supply services that are reliable, applicable, and cost-effective. The cloud reflects a provider’s core competencies.
Costs are associative
Due to the flexible resource allocation model of the cloud, it’s just as easy to acquire and operate 100 servers for one hour as it is to acquire and operate one server for 100 hours. This opens the door to innovative thinking with respect to ways of partitioning large-scale problems.
Here are some of the defining characteristics of the Amazon Web Services from the technical standpoint:
Scaling is quick
New hardware can be brought online in minutes to deal with unanticipated changes in demand, either internally (large compute jobs) or externally (traffic to a web site). Alternatively, resources can be returned to the cloud when no longer needed.
Infinite scalability is an illusion
While not literally true, each consumer can treat the cloud as if it offers near- infinite scalability. There’s no need to provision ahead of time; dealing with surges and growth in demand is a problem for the cloud provider, instead of the consumer.
Resources are abstract and undifferentiated
Cloud computing encourages a focus on the relevant details—results and the observable performance—as opposed to the technical specifications of the hardware used. Underlying hardware will change and improve over time, but it’s the job of the provider to stay on top of these issues. There’s no longer a need to become personally acquainted with the intimate details of a particular dynamic resource.
Clouds are building blocks
The cloud provides IT resources as individual, separately priced, atomic-level building blocks. The consumer can choose to use none, all, or some of the ser- vices offered by the cloud.
Experimentation is cheap
The cloud removes the economic barrier to experimentation. You can access temporary resources to try out a new idea without making long-term commitments to hardware.