To Wikibon's credit, the definition of "Private Cloud" is an issue that needs to be addressed. In my career I have seen too many organizations overuse the term "Private Cloud". I have seen a VMware cluster deployed on disparate hardware with no upper level cloud management platform called a private cloud. I have seen converged infrastructure, acquired but managed identically to non-converged infrastructure (as discrete components each managed by their functional staff) called private clouds.
Converged infrastructure plays a role in a private cloud, be even that term is challenged. I have seen disparate servers and storage, purchased separately at different times, cobbled together and called converged infrastructure after the fact. I have also seen single-SKU converged infrastructure broken apart, support for component infrastructure separated, and individual components upgraded on different life-cycles.
From an operations perspective, I have seen mature IT organizations in large enterprises provide similar levels of managed services as traditional managed service providers. I have also seen the converged infrastructure single-support model dramatically fail organizational customers, and provide no better single support that that provided by an reseller or managed service provider.
If the goal of a "true" private cloud is to provide a similar level of service offering to internal end-consumers they receive from a public cloud, but with higher levels of compliance and data sovereignty, then much of the detailed requirements Wikibon mentions are not necessary. As long as the organization can provide an offering to internal end-consumers which is competitive (on cost, ease of consumption, and reliability), it should meet the definition.
Here are what I believe are required of a "True" Private Cloud:
- Acquired in consolidated units of management, virtualization, compute, network, and storage with common amortization, and common life-cycle management.
- Components supported as an integrated whole, with a single number, first-call support model, and escalated support abstracted from the internal end-consumer.
- Compute, storage, network, and virtualization managed as a single entity by a single, cross-functional team.
- Provisioned and managed via a cloud management platform (CMP).
- Consumed by internal end-consumer as a shared resource in logical, not physical increments, i.e., VMs and GBs.
- End-consumer offerings include multiple performance and data protection SLAs.
- Provides charge-back to internal end-consumers.
- Provides the Private Cloud operator performance, capacity, and licensing budgeting of the infrastructure; performance metering and capacity measurement to manage over-subcription, prevent over-consumption (especially of performance), and allow for elastic performance and capacity scaling; and provide built-in performance and capacity planning for predictable infrastructure growth.
- Managed by high IT maturity organizational customer IT staff, or optionally part of a managed services offering that does not require organizational customer IT staff to manage.
- Financed to organizational customer either through capital purchase, capital lease, operational lease, capacity lease, or pay-per-use offering.
Some organizational customers will want to capitalize the "True" Private Cloud and manage it themselves. Others will want to basically rent the whole stack to include the software, and have it managed for them. But the common denominator should be how the internal end-consumer consumes the offering. It should look, feel, and cost as much like the public cloud as possible.