"The “Cloud” concept is finally wrapping peoples’ minds around what is possible when you leverage web-scale infrastructure (application and physical) in an on-demand way. “Managed Services”, “ASP”, “Grid Computing”, “Software as a Service”, “Platform as a Service”, “Anything as a Service”… all terms that couldn’t get it done. Call it a “Cloud” and everyone goes bonkers. Go figure."
- Damon Edwards

"There sure is a lot of confusion when it comes to talking about cloud computing. Yet, it does not need to be so complicated. There really are only three types of services that are cloud based: SaaS, PaaS, and Cloud Computing Platforms. I am not sure being massively scalable is a requirement to fit into any one category."
- Brian de Haaff

"SaaS is one consumer facing usage of cloud computing. While it's something of a semantic discussion it is important for people inside to have an understanding of what it all means. Put simply cloud computing is the infrastructural paradigm shift that enables the ascension of SaaS."
- Ben Kepes

"The 'cloud' model initially has focused on making the hardware layer consumable as on-demand compute and storage capacity. This is an important first step, but for companies to harness the power of the cloud, complete application infrastructure needs to be easily configured, deployed, dynamically-scaled and managed in these virtualized hardware environments."
- Kirill Sheynkman

"I was chatting with a customer the other day who was struggling with some of the implications of cloud computing. The analogy that finally made sense to them is what I will call 'cloud dining.' I am the cook in the house and I am tasked with feeding the family. If my 10-year old is lobbying for Italian, I am cook at home or order out. The decision may also vary from day to day. For instance, I might not have all the ingredients and have to order out, or, like this weekend, it may be 103 outside and cooking at home is not all that appealing. Now, the same can be said for supporting a given application in a cloud computing environment.

In a fully implemented Data Center 3.0 environment, you can decide if an app is run locally (cook at home), in someone else’s data center (take-out) and you can change your mind on the fly in case you are short on data center resources (pantry is empty) or you having environmental/facilities issues (too hot to cook). In fact, with automation, a lot of this can can be done with policy and real-time triggers. For example, during month end processing, you might always shift non-critical apps offsite, or if you pass a certain cooling threshold, you might ship certain processing offsite."
- Omar Sultan

"Cloud computing overlaps some of the concepts of distributed, grid and utility computing, however it does have its own meaning if contextually used correctly. Cloud computing really is accessing resources and services needed to perform functions with dynamically changing needs. An application or service developer requests access from the cloud rather than a specific endpoint or named resource. What goes on in the cloud manages multiple infrastructures across multiple organizations and consists of one or more frameworks overlaid on top of the infrastructures tying them together. The cloud is a virtualization of resources that maintains and manages itself."
- Kevin Hartig

"Clouds are vast resource pools with on-demand resource allocation. The degree of on-demandness can vary from phone calls to web forms to actual APIs that directly requisition servers. I tend to consider slow forms of requisitioning to be more like traditional datacenters, and the quicker ones to be more cloudy. A public facing API is a must for true clouds.

Clouds are virtualized. On-demand requisitioning implies the ability to dynamically resize resource allocation or moving customers from one physical server to another transparently. This is all difficult or impossible without virtualization.

Clouds tend to be priced like utilities (hourly, rather than per-resource), and I think we’ll see this model catching on more and more as computing resources become as cheap and ubiquitous as water, electricity, and gas (well, maybe not gas). However, I think this is a trend, not a requirement. You can certainly have clouds that are priced like pizza, per slice."
- Jan Pritzker


See next page for definitions from Trevor Doerksen, Thorsten von Eicken, Paul Wallis, Michael Sheehan, Don Dodge, Aaron Ricadela, Bill Martin, Ben Kepes and Irving Wladawsky Berger