Microsoft has revealed cost and service-level details for its Azure cloud platform for the first time.
On Tuesday, the software giant set out pricing options and service-level commitments for Azure, providing potential customers with their first opportunity to assess the cost of the development and hosting platform against longer-established rivals.
Microsoft also confirmed that Azure will be available in the US, Europe and Asia from mid-November.
Mark Taylor, director of developer and platform evangelism, said commercial availability of the Windows Azure platform will be announced at Microsoft's Professional Developers Conference in Los Angeles in November.
"It will go commercial in November," he said. "In the first half of the next calendar year, we are going to talk about international availability — about additional datacentres and about additional countries that Azure will be available in."
He added that customers would be able to specify where their data would be hosted.
Taylor said there will be three ways of using Azure: pay-as-you-go, subscription and volume licensing. "With pay-as-you-go, you put your credit card in and buy compute or storage capability. That will be available at launch and is a low cost and low risk to entry. It allows you to take advantage of the elasticity that cloud computing gives you," he said.
Organisations with well-defined requirements could use the subscription model, which will also be available at launch. "It provides discounts over pay-as-you-go and allows you to drive some costs down," Taylor said.
Microsoft would also add Azure access to existing Enterprise Agreement licences, according to Taylor. "Customers won't have to have an Enterprise Agreement and a different arrangement for Azure. The discounts they get through Enterprise Agreement licensing will apply to Azure as well," he said.
The Windows Azure application platform will be charged at $0.12 per service hour. "To put this in perspective, this is your application platform. This is not a virtualised server, so this is the capability to run the application. There is no requirement in Azure to, say, patch an operating system, which is the case in the alternative services," he said.
Storage will be charged at $0.15 per gigabyte, per month, and transactions in and out of that storage cost $0.01 per 10,000 transactions.
As a comparison, Amazon Web Services, which launched its first cloud service, the Simple Storage Service (S3), in March 2006, charges storage in Europe on a sliding scale, starting at $0.18 per gigabyte per month for the first 50TB.
Microsoft's SQL Azure database is available in a Web Edition and a Business Edition. The Web Edition offers a smaller database, 1GB of which costs $9.99 (£6.10) per month. Under the Business Edition, 10GB costs $99.99 per month. "When you provision a database in the Azure environment, you create three copies, and that gives you some resilience at an application level if one of those copies gets corrupted," Taylor said.
The .NET Services message orchestration services that run other .NET applications cost $0.15 per 100,000 message operations.
Microsoft said data coming into Azure is charged at $0.10 per gigabyte, with outbound data priced at $0.15 per gigabyte.
The company also set out the details of its service-level agreements (SLAs) for Azure. "As we know, the cloud is not entirely bomb-proof — we've seen some significant outages recently," Taylor said. "From our viewpoint, we will offer SLA credits against our service levels."
Microsoft will provide a 10 percent credit if compute connectivity falls below 99.95 percent uptime; a 10 percent credit if role-instance uptime or storage falls below 99.9 percent uptime.
"If we fall below 99 percent availability across anything, we will be providing 25 percent credits," said Taylor.
