News

Windows Azure Pricing Unveiled

• By Kurt Mackie
• 07/16/09

Microsoft announced pricing for its Windows Azure cloud computing services Tuesday at its Worldwide Partner Conference in New Orleans.

Windows Azure cloud computing services are currently available for free to participants in Microsoft's community technology preview program. However, the company plans to start offering commercial services on a pay-as-you-go basis when the Microsoft Professional Developers Conference begins in late November.

Microsoft also plans to offer a promotional discount to its partners of five percent on "Windows Azure compute, SQL Azure and .NET Services," which are all part of the Windows Azure Platform. In addition, the company is planning a "development accelerator promotional offer" that will provide a "deep discount" to partners and customers who want to quickly develop and deploy hosted applications on the platform.

The pricing details are described in Microsoft's Windows Azure team blog here. A more detailed analysis of the cloud computing platform, with explanations about how Windows Azure services are priced, is provided in a July white paper by David Chappell, "Windows Azure and ISVs" (PDF).

Chappell argues that cloud computing platforms such as Microsoft's Windows Azure are typically needed by software distributors that deliver applications to their customers via software as a service. Those thinking about hosting their Web site using Windows Azure likely will find Windows Azure service to be an expensive overkill, according to a Microsoft Developer Network (MSDN) forum post.

"I doubt there are many hosting providers who would appreciate you calculating the next Mersenne prime between serving up Web pages," explained Neil Mackenzie in an MSDN blog post. "The practical reality is that neither Azure nor AWS [Amazon Web Services] are (price) optimized for hosting a simple Web site because it costs a lot more to support their virtualized platforms than it does to support a virtual directory."

Chappell explains in his white paper that Microsoft's Windows Azure pricing is based on three basic variables: "compute time, data storage and access, and bandwidth transferred in and out."

Microsoft will charge $0.12 per hour for compute time, $0.15 per gigabyte of storage per month and $0.01 per 10,000 operations on that stored data, according to Chappell. The bandwidth charge is $0.10 per gigabyte moving in and $0.15 per gigabyte moving out.

There appears to be a way for customers to "remove compute instances" to limit compute time charges, according to a discussion on the MSDN forum.

In addition to the above charges, if customers use the platform's SQL Azure relational database for storage, they will get charged by how much data is stored, plus bandwidth costs.

There are two SQL Azure options--a Web Edition and a Business Edition. The Web Edition costs $9.99 per month for up to one gigabyte of storage, with a max query time of 10 hours. The Business Edition costs $99.99 per month for 10 gigabytes of storage, with a max query time of 100 hours.

With all of those pricing variables, it all sounds fairly complex to calculate what it will cost to use Windows Azure services on a monthly basis. The Windows Azure team blog hinted that Microsoft plans to relax the pricing for some customers that require "payment predictability" and can commit to a certain level of use.

"While consumption-based pricing provides great flexibility, we have also heard it introduces a level of unpredictability and some customers prefer other options," the blog explains. "At launch [at the PDC], we will share details of subscription offers that provide payment predictability and price discounts that reflect levels of usage commitment."

Microsoft's cloud computing pricing is somewhat similar to that of Amazon Web Services, according to a Burton Group datacenter blog. However, Microsoft has thus far failed to specify any pricing distinctions based on the level of computing resources consumed by users.

"The missing part in the model is the size (or type in EC2 terms) of the compute platform," wrote Drue Reeves, vice president and research director at Burton Group. "I don't think Microsoft would allow an application that requires 5x the amount of memory or CPU time to be the same price as another application with lesser requirements."