As I wrote some lines about cloud and outsourcing lately and had some interesting discussions “about the cloud”, I will deepen this interesting topic.
The cloud is coming (it’s not as dark as it sounds – we expect a rather sunny future…) – The cloud is on everybody’s mouth by now and there are really some promising scenarios. Also the ‘big fish’ (like SAP, HP, IBM, Google and Microsoft) are rising campaigns about this issue. But most of the people I’ve talked to have some very different views about what “cloud computing” is.
It is very important to have a common sense about what a cloud is to talk about cloud aspects – if you want to work on this topic. A really good basis can be the definition of the NIST (National Institute of Standards and Technology, an agency of the U.S. Department of Commerce), by Mell and Grace (see [MeGr09]).
However, NIST points out following aspects:
- 5 Characteristics: On-demand self-service, Broad network access, Resource pooling, Rapid elasticity, Measured Service.
- 3 Delivery methods: Cloud Software as a Service (SaaS), Cloud Platform as a Service (PaaS), Cloud Infrastructure as a Service (IaaS).
- 4 Deployment models: Private cloud, Community cloud, Public cloud, Hybrid cloud.
Details can be read in the document of the authors. Mell and Grace point out, that their definition might change over time and make two notes:
- “Note 1: Cloud computing is still an evolving paradigm. Its definitions, use cases, underlying technologies, issues, risks, and benefits will be refined in a spirited debate by the public and private sectors. These definitions, attributes, and characteristics will evolve and change over time.
- Note 2: The cloud computing industry represents a large ecosystem of many models, vendors, and market niches. This definition attempts to encompass all of the various cloud approaches.” [MeGr09]
Therefore it is no surprise that the NIST characteristics are adapted and modified (by affected) in some blog posts, e.g. by Chou (see [Chou11]). But Chou thinks in another way about the delivery methods: He differs only private and public cloud. In addition, he sets here and there a different focus of the cloud characteristics.
After all, Chou builds a “5-3-2 principle” on the solid definition of NIST from Mell and Grace (5-3-4 with them) including 5 characteristics, 3 delivery methods and 2 deployment models (see [Chou11]).
“The 5-3-2 principle is a simple, structured, and disciplined way of conversing cloud computing. 5 characteristics, 3 delivery methods, and 2 deployment models explain the key aspects of cloud computing.” [Chou11]
Consequently, you can hear anywhere other “key characteristics” of clouds – another example: An expert I’ve talked to last Friday told me, form his point of view, cloud is only cloud if there are “near real-time updates” by the provider “without warning”, the software could not be installed on local or corporate machines respectively and access to the cloud applications is exclusively possible with a web browser. Following this definition, the term “cloud computing” is more restricted, not all “so called” clouds are clouds from this point of view…
Interested? So follow me on twitter (@BorisDombrowski) or facebook (www.facebook.com/BorisDombrowski) or visit this blog again. I will seize this topic again…
Reference list:
- [Chou11] Chou, Yung: “Chou’s Theories of Cloud Computing: The 5-3-2 Principle.” URL: http://blogs.technet.com/b/yungchou/archive/2011/03/03/chou-s-theories-of-cloud-computing-the-5-3-2-principle.aspx, last verified on March 28, 2011
- [MeGr09] Mell, Peter; Grance, Tim (both NIST – National Institute of Standards and Technology, an agency of the U.S. Department of Commerce): “The NIST Definition of Cloud Computing.” URL: http://csrc.nist.gov/groups/SNS/cloud-computing/cloud-def-v15.doc, last verified on March 28, 2011