I suppose I pay rather close attention to cloud deployment models for a variety of reasons. I ran across an article today at cio.com called, "How to Build a Hybrid Cloud Computing Strategy." http://www.cio.com/article/493492/How_to_Build_a_Hybrid_Cloud_Computing_Strategy
In particular, it listed three deployment models for cloud computing:
- Public clouds. These deliver the best economies of scale, but their shared infrastructure model can limit configuration, security, and SLA specificity, making them a less-than-ideal fit for services using sensitive data that is subject to compliancy or safe harbor regulations.
- Internal clouds. These sit within your data center and behind company-built protections, but they typically have modest economies of scale due to funding limitations and tend to be less automated.
- Hosted clouds. Hosted clouds run at a service provider on resources that are walled off with enterprise-class protections but managed as a pool. These fall between the first two options, providing more custom protections like an internal cloud but with the greater economies of scale of being a service from a cloud provider.
Another set of deployment models come from NIST that I've posted here before:
- Private cloud. The cloud infrastructure is operated solely for an organization. It may be managed by the organization or a third party and may exist on premise or off premise.
- Community cloud. The cloud infrastructure is shared by several organizations and supports a specific community that has shared concerns (e.g., mission, security requirements, policy, and compliance considerations).
- Public cloud. The cloud infrastructure is made available to the general public or a large industry group and is owned by an organization selling cloud services.
- Hybrid cloud. The cloud infrastructure is a composition of two or more clouds (private, community, or public) that remain unique entities but are bound together by standardized or proprietary technology that enables data and application portability (e.g., cloud bursting).
What's interesting to me is that each of these calls out a few specific points of reference that delineate them. They are:
- Where is the infrastructure physically?
- Who owns the infrastructure(aka Pays the bills)?
- Who uses the infrastructure?
- How is the infrastructure accessed?
Christofer Hoff has done a lot of good thinking on this and his thoughts are well summed up here and worth a read: http://www.rationalsurvivability.com/blog/?p=743
He produced a nice diagram that I think is quite good.
In any event, there is some seeming convergence occuring in the cloud deployment model thinking here and there. I'm pleased to see this occuring for sure. Things have come a long way in a short time.