App Virtualization Pays Off for Developers
What started as a quick fix for incompatibility issues has become a viable alternative app-deployment model.
Application virtualization found its way into the enterprise as a Band-Aid for incompatible apps, but is now starting to catch on as an alternate software deployment model. This trend bodes well for corporate developers stuck writing code for outdated frameworks and maddeningly heterogeneous deployment environments, vendors and analysts say.
Application virtualization products from Microsoft, Altiris, Citrix Systems Inc. and Thinstall isolate programs from the host operating system by confining the app and its requisite DLLs and registry keys to a self-contained package. A virtualized app doesn't clash with installed programs because it's essentially sealed inside a bubble.
Proactive use of the technology could one day free developers to write code without being hamstrung by potential application and platform conflicts.
"The initial entry point is, 'Hey, I've got an app that conflicts with everything else, so I'll just virtualize it,' but the real impact is that this product basically lets you turn any Windows app-from DOS to .NET-into a service," says David Greschler, Microsoft's director of system center virtualization. "It's really about turning apps into data."
If application virtualization gains widespread acceptance as a software-deployment model, as some observers expect, development teams would no longer be shackled by compatibility concerns. Some application virtualization products even enable developers to write code for the latest operating system without regard for which OSes end users are running.
"As a developer, you can take more liberties and include stuff that's cool, but up until this point you would've been prohibited from that because of rollout issues," says Henrik Rosendahl, executive vice president of Thinstall.
For that matter, he adds, the entire .NET 3.0 Framework can be wrapped into a virtualized application, eliminating the possibility of platform conflicts and allowing a developer to tap the latest version of the framework long before his company migrates to it. Thinstall customers have created virtualized application packages as large as 4GB without any deterioration in performance, Rosendahl says, because they're streamed in smaller blocks as needed from a server, CD-ROM or even a memory stick.
Forrester Research Inc. has been surveying companies to gauge how widely application virtualization is being used today. Forrester analyst Natalie Lambert says the technology is seeing more use in enterprises.
"With Office 2007 rolling out this year, it's going to significantly increase the adoption of these technologies," she says. "With business-critical macros, you can't just switch to Office 2007. You need a way to deploy these new solutions without wrecking everything else."
And as companies get comfortable pushing out applications in virtualized form, the thinking goes, in-house development teams eventually could start coding their apps with that method of delivery in mind.
"Developers have a lot of motivation to embrace this technology," says Scott Jones, product manager for Altiris Software Virtualization Solution (SVS). "You don't have to worry about breaking pre-existing stuff on the clients, nor do you have to worry about having pre-installed stuff break your application."
Nabeel Youakim, product line executive for Citrix's Presentation Server, which now includes application virtualization functionality, says developers need only refrain from coding direct calls to the PC hardware. "As long as they're developing to a good Windows environment using Microsoft tools and practices, they don't have to do anything different," he says.
However, applications that require access to kernel mode, such as virus scanners and VPN clients, wouldn't be good candidates for virtualization because the technology essentially walls off an application from the host PC.
So Long, Install Packages
Jones says he often hears of enterprise developers and packaging teams trying to pass the buck to each other when it comes time to build install packages for a new app. Application virtualization eliminates the need for that chore because, strictly speaking, the program isn't installed.
"If you can get an implementation of the application that functions correctly in the lab, you can save that as the virtual software package with all the files and registry keys in the correct place with their dependencies," Jones says. "You just zip that up and deploy it to the clients."
Microsoft's Greschler, who co-founded application virtualization vendor Softricity, puts it this way: "It's just plain easier to get your software out this way."
Redmond bought Softricity last year to join the growing market, and Symantec Corp. completed its acquisition of Altiris in April. Citrix and Thinstall are the newest market players. The four vendors, while each touting their own approach to application virtualization, all agree the technology is on the verge of evolving from a compatibility fix to a new way to deploy software.
Gartner Research Inc. analyst Mark Margevicius agrees. "The growth is good, and the uptake is fairly good, and the opportunity that lies ahead is absolutely good," Margevicius says, adding, "I wouldn't be surprised if more vendors try to stick a toe in the water and see how warm it is."
Forrester's Lambert is even more bullish. "As this technology begins to take off," she predicts, "it will become a native feature of the OS."