We assembled this list with help from analysts at Cloud Technology Partners, Current Analysis, Enterprise Strategy Group, Gartner, IDC and Neovise who watch the public cloud Infrastructure as a Service scene very closely. Each was asked to name the companies they believed have the most influence - whether that's measured in market share, mind share, revenue, existing enterprise pull or underlying technology links - in drawing enterprise customers into the realm of public cloud infrastructure. They are listed here in alphabetical order.
1. Amazon Web Services: The gold standard
Amazon is the standard bearer in the public IaaS space, as its paid-by-the-VM Elastic Compute Cloud (EC2) is both the market share and mindshare leader by a fairly big gap. It's got a huge portfolio of services that run atop its Xen-based virtualized infrastructure and Amazon keeps adding to those offerings while it lowers its prices. The company has built a thriving ecosystem of partners around its public cloud, has clamored to get all the necessary security and compliance certifications and offers world-wide data centre coverage.
2. Bluelock: Out of the blue
As a surprise pick as a market leader in the recently published Gartner Magic Quadrant for public cloud IaaS, this 5-year-old Indianapolis-based cloud provider has been gaining some national name recognition. The company's offering is called Bluelock Virtual Data Center, is based on VMware's vCloud, and can be used to build public, private or hybrid cloud deployments and is driven by a strong portal that includes many tools that allow customers to understand how much and which cloud-based services are costing them the most money.
3. CSC: Targeting the enterprise
CSC is a traditional IT outsourcing vendor that latched onto the cloud two years ago, invested heavily in it, and is now getting significant traction with its VCE (the joint VMware, Cisco, EMC venture) Vblock-based CloudCompute IaaS offering. CloudCompute comes in three flavors: public, multitenant hosted at a CSC site; private, single tenant in a CSC data center; and private, single tenant located at the customer's site. CSC gets points for having a common architecture across all the offerings and has outlined a clear plan for how it plans to give enterprise customers the types of management tools to which they are accustomed.
4. GoGrid: All cloud, all the time
GoGrid prides itself on being a pure-play cloud company offering both public and private Xen-based IaaS with optional managed services. This small company has had good success delivering on that story, placing among the top five public cloud IaaS vendors when you count virtual machines and factor in its very competitive price. GoGrid's effort to build a third-party ecosystem on top of its IaaS is called GoGrid Exchange, essentially a program that allows partners to sell their software products on top of GoGrid server images, thereby easing the issues customers sometime face when trying to deploy applications in the cloud themselves.
5. IBM: Leveraging the installed base
With a newfound devotion to the public cloud, IBM plans to cash in on its existing client base and support about 200 million users by the end of 2012 as clients shift core applications and processes to the company's cloud. IBM has recently made huge investments to the underpinnings of its KVM-virtualised public cloud IaaS, rebranded the service as SmartCloud Enterprise and SmartCloud+, and announcing plans to tie in more managed services and enterprise features to it this year.
6. OpenStack: No vendor lock-in
OpenStack is an open source cloud computing platform project started in the summer of 2010 by IaaS vendor Rackspace and NASA. It's got three core component projects up and running, with two more incubating and another 16 coming from the wider community. The draw of an open source platform is that if you use one (either one that you build yourself or one commercialised by an IaaS provider) your applications will not ever be locked to a proprietary vendor. At press time, the project had the backing of 159 companies and 2,685 people actively contributing to the code base.
7. Rackspace: Taking a leadership role
Rackspace went public in 2008. Since then, the company has seen a 400 percent growth in revenue. It beat analysts' estimates across the board in 2011. Net income was up from 2010 by 85 percent to $25 million and revenue grew 32% to $283.3 million. In particular, revenue for the public cloud business - driven by a Xen-virtualised service called Cloud Servers -- was up 86% from the previous year's quarter to $58.5 million. Cloud Servers has been hailed as a very easy to use server that comes with exemplary customer service and a low price. Rackspace's direct ties to the OpenStack open source cloud platform project will likely help build its ecosystem further.
8. Savvis: Full range of options
Savvis - which is owned by CenturyLink - markets its VMware-driven public cloud IaaS called Symphony Virtual Private Data Center right alongside its private cloud offering and with the optional managed services it has already built its enterprise reputation upon. The company offers tiered levels of services, service level agreements and prices to match those levels. The company has put a huge emphasis on deep security and a unified portal across all of its services. The combination puts Savvis in the top five market share leaders in the VMware public cloud IaaS bucket.
9. Terremark: Three-pronged VMware-based approach
Terremark - which is owned by Verizon - has three feet in the public cloud IaaS space. The Enterprise Cloud (which is driven by VMware) homes in on virtual data center needs and is sold in blocks of resources as opposed to VM instances. Enterprise Cloud Managed Edition focuses on facilitating hybrid public/private clouds. With vCloud Express - which you buy by the VM - Terremark is targeting developers who need to do test out applications they are building for the cloud. Terremark's three-pronged approach has put the company pretty high up on the leaderboard.
10. VMware: Key building block
Four of the other nine companies on our list of the most powerful vendors in the public cloud IaaS space are betting on their VMware software-based infrastructures to allow them to keep playing in this growing space in enterprise computing. We've chosen to include VMware in the list based on the premise that if it sneezes, a big portion of the rest of the public cloud is going to get a cold.