Web server survey site Netcraft's recent report may have indicated Microsoft's IIS is gaining ground over the venerable open source Apache HTTP server, but version 7.0 is promising to take the challenge to the next level.

The August 2007 Netcraft survey collated responses from 127,961,479 Web sites and concluded Microsoft continues to increase its Web server market share with another 2.6 million sites during the month, while Apache lost some 991,000 host names.

In percentage terms, Windows improved its market share by 1.4 percent to 34.2 percent and Apache dropped by 1.7 percent to 48.4 percent.

This is in stark contrast to the November 2005 survey where Apache was found on 71 percent of Web sites and IIS on just over 20 percent.

"If Microsoft continues to gain share at its current pace, it could close the gap on Apache sometime in 2008," according to Netcraft. "Microsoft's recent gains raise the prospect that Windows may soon challenge Apache's leadership position."

Microsoft's IIS team senior program manager Eric Deily said the modularity of Apache is "very appealing" and is something the company is striving to correct and offer in IIS 7.0.

In addition to numerous architectural changes, the most significant advancement in IIS 7.0 over previous releases is native support for numerous open source development environments like PHP, Python, and Ruby on Rails through FastCGI.

"One imperative was to support FastCGI," Deily said, adding PHP and FastCGI on IIS can be just as fast as Apache on Linux.

"One customer is implementing FastCGI for IIS 6.0 and they use Visual Studio and php.net to do all development so it's an interesting blend of non-Microsoft technology and Windows."

This new found love of open source environments was also driven by hosting companies which typically offer customers PHP-based applications, like the Wordpress blog.

"Hosters have so many applications like Wordpress that can now be used with Windows so IIS is now targeting the hosting market," Deily said, adding the IIS team is actively doing a lot of compatibility testing.

"Now it's about choosing the right platform for the job and the barrier to entry for an IIS manager is lower than an Apache Web site."

On the Gold Coast to speak at this year's Tech.Ed conference, Deily is confident the improved manageability of IIS 7.0 will also give it a leg up over Apache.

"The IIS configuration is not machine dependent any more so when I deploy my machine I can use one machine to host a config file," he said. "Your front ends are truly headless. All the guts are on the [shared] server and previously there wasn't a central configuration repository."

Another catch up to Apache will be IIS 7.0's extensibility, both with the native API and new PowerShell scripting environment due for release with Windows Server 2008.

"Customers can develop extensions with same API that Microsoft uses," Deily said. "In IIS 7.0 you can replace default functionality with others by Microsoft and third-parties."

Also at Tech.Ed, Microsoft's technology platform manager for Web platform and tools, Eric Woersching, said the IIS "ecosystem" is becoming more vibrant because of it's modularity and the IIS portal, www.iis.net, hosts third-party extensions and discussion forums.

"Customer feedback drove this, and I know it's a page out of open source but it makes sense," Woersching said.

He added that a pre-release of IIS 7.0 shipped with Windows Vista which has the same core Web server to allow developers to develop and deploy applications transparently.

Woersching said the SQL Server team is working on a native PHP driver.

"With Apache you build a solution from different sources but with IIS you have one package and now its modular," he said. "You can use IIS to configure PHP. PHP was built for Apache and wasn't something we concentrated on but supporting PHP made sense."

Ken Schaefer from Avanade Australia, a services company partly owned by Microsoft, said IIS 7.0 comes with .Net which can be used to enhance or modify the modules.

"For example, you can write your own authentication module to talk to eDirectory or PeopleSoft and you can write that in .Net," Schaefer said. "The whole stack has been reengineered to perform better."

IIS 7.0 is due for release with Windows Server 2008 early next year. Previous version of Windows Server are not supported.