When Adrian Cockcroft talks cloud, people listen. Or they should.

He's the former cloud guru at Netflix(s nflx) and drove that company's use of Amazon Web Services(s aws). Since he left Netflix in January to join Battery Ventures as technology fellow he's been traveling the world, talking to IT buyers about their tech plans. He will reveal what he learned at the Cloud Trends session at Structure Thursday.

Here are some highlights:

Amazon still reigns supreme, but ...

For the first time in its history, AWS(s amzn) is seeing cloud rivals in its rearview mirror. Microsoft(s msft) Azure, in particular, has Amazon looking over its shoulder. That's not to slight Google's cloud, which is growing fast, but his view is that Google will not be a huge factor in enterprise computing.

Location, location, location(s) matters

Cockcroft believes all the major cloud providers will expand their presence in big markets -- especially England, France and Germany. I have long suspected AWS will put new data centers in Germany, Switzerland or other locales where data sovereignty laws are strict.

Amazon CTO Werner Vogels was typically tight-lipped on this prospect at Structure Wednesday. But the fact is, big business and government customers do care about keeping data in-country. That may be as subset of the overall market, but it's a heckuva big subset. If AWS is serious about winning more government and enterprise accounts it's going to have to add more regions in Europe, Asia, elsewhere. And no one doubts that it is deadly serious on that front.

A big bank in Australia has designated AWS and Azure as its preferred public cloud vendors and is "working through the regulatory stuff so that they can deploy all they want on those platforms and be compliant," he said in an interview before his presentation. That would mean that any data processed on those clouds would be counted as if it was on-premises.

One big reason for that designation is that both AWS and Azure have an Australian region. What's interesting is in countries where there's an interesting development community and a cloud vendor with a presence, companies are adopting cloud far more aggressively because they can keep their data in country. "Australians don't want their data in Singapore or Taiwan," he said.

And Google(s goog) for all its resources, is trailing here, by his account. Google has three cloud regions -- in Belgium, Taiwan and in central U.S., and he thinks it needs to add more. Amazon has ten regions, including Gov cloud. Microsoft has 15.

landgrab

OpenStack, at least in name, will do fine in private cloud

OpenStack, as a brand, is a wild success, at least in private cloud. "The marketing war for CIO mindshare has been won. They'll buy anything as long as its called OpenStack," he said. IBM is doing it, HP is doing it, Rackspace is doing it. "There is too much vested interst in openstack so all the vendors will do openstak and will become like linux so everyone adopted it but it did fragment a bit

The bad news is that all the vendors will do what they have to do to remain true to OpenStack core code, but will innovate atop that in ways that will limit true interoperability, he said. He expects the OpenStack standard to "fragment into similar but incompatible stacks."

In his view, OpenStack does not scale to public cloud proportions. "OpenStack's code set is optimized to solve enterprise IT problems. It needs to be easy to install versus being hugely scalable," he said. Mesos, used by Twitter(s twtr), AirBnb and other companies,  looks to become the big scalable backend for non AWS public clouds.

Enterprise cloud adoption is upon us

Most companies run a mix of Linux and Microsoft technologies and in most cases when it comes to public cloud decisions, the Linux side of the house will opt for Amazon while Windows shops will go for Azure or perhaps VMware's cloud, Cockroft said. Most companies he talked to already have put AWS on their approval list.

Many of Cockcroft's conclusions reinforce what's been in evidence this week at Structure: Namely, that when it comes to public cloud, the discussion is now AWS, Microsoft Azure and Google.

Asked which clouds will prevail going forward, execs from HP, VMware and IBM all said: AWS, Microsoft, Google. And then, of course, they added their own cloud services to the list.

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