"The question of opex v capex is an important commercial dimension, but I would not want to be using it to say that something is or is not cloud," says O'Rourke.
Dell also does not see private cloud as something that must be offered on an opex basis.
"With Dell Private Cloud we offer customers a 'your place or ours, your books [financial] or ours, and your place [data centre] or ours' solution," says Kyle Bunting, cloud services director, Dell Asia Pacific and Japan.
According to Hanrahan the market is wising up to the true meaning and potential of private cloud.
"We are finding that the NIST definition of cloud is becoming more commonly accepted. In a number of tenders recently in Australia we have seen requests to "describe your service against the NIST definitions and how it meets the five critical characteristics". We're seeing the industry as a whole becoming far more mature about cloud."
Dimension Data operates a standard public cloud offering. "It is paid on consumption of shared resources - storage, virtual machine hours and RAM," Hanrahan said. "It can scale up and scale down and it is billed for on consumption and all the administrative functions are available to a self-service layer."
The company's private cloud service is functionally identical but uses dedicated servers, memory and storage installed either in Dimension Data's data centre or on the customer's premises.
"It uses the exact same architecture and technology, the same orchestration automation and control centre API and self-service functionality ... Customers still don't own the asset, they still pay by usage," Hanrahan says.
With the customer premises version Dimension Data pre-installs excess capacity that is available to the customer on demand and on a pay-for-usage basis in the same way as a public cloud. If additional capacity beyond this is required there will be a delay of some days while it is shipped in and installed.
According to Hanrahan, "The key business advantage they get from this arrangement is that, were they to buy the same infrastructure they would have to do a best-guess estimate of peak load at a point in the future, and quite often they get that wrong."
Hanrahan said that the on-premise private cloud was very much an extension of the public cloud offering. "We use the exact same infrastructure as public. We monitor it with the same tools and the same people. It has the exact same characteristics as a public cloud."
Fujitsu also offers private cloud facilities integrated with its public cloud offering and where the private infrastructure can be in the customer's or in a Fujitsu data centre.
John Kaleski, general manager, cloud, Fujitsu Australia and New Zealand, says it provides the scale and other benefits of public cloud for data that is not location sensitive, but enables customers to quarantine sensitive data in their private cloud.
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