The application virtualization market is young and in constant change, which makes it especially tricky for IT managers trying to sort out who is selling what and also, precisely how the job is getting done.
Each vendor has different delivery, packaging and licensing approaches, but the end goal is the same: Capture the application, and the files and settings it needs to execute, in a virtualized capsule, separate from other applications, the host OS and hardware.
The application can run from a virtualized bubble on a desktop, from a thumb drive or through terminal services, a shared network drive or server, among other options. The delivery method depends on the given technology's capabilities.
Some vendors are repositioning existing technology for new uses such as DataSynapse Inc. in New York City, which is known for grid computing. The company's technology executes applications on a local server, but the applications can be moved from server to server without mixing with the underlying hardware. This technology is mainly being looked at by Linux shops.
For Windows shops, the early market entrants are Microsoft SoftGrid and Citrix Presentation Server 4.5.
"Windows shops are going to go with SoftGrid and Citrix because that fits the application model they already have in place, so there's not a whole lot of education," said Michael Rose, an analyst with IDC, the Framingham, Mass.-based market research company.
Microsoft acquired SoftGrid technology when it bought Softricity in May 2006. SoftGrid, Citrix Presentation Server 4.5 and Altiris Software Virtualization Solution all isolate applications from the underlying host operating system and applications and require a client-side agent. Microsoft and Citrix also embed application streaming with their application virtualization technology; while Altiris has joined forces with AppStream Inc. to stream virtualized applications.
Applications are streamed from a data center or server, but they can also reside on other devices like a desktop or thumb drive, and still be considered virtualized applications. It is not unheard of, for example, for a user to run a virtualized application from an iPod.
Others entering the market are Thinstall, out of San Francisco, and Trigence Corp., based in Jersey City, N.J. Both companies take a similar approach by isolating the application and the files, libraries, codes and scripts needed to run the application in an executable file.
Third-party streaming can be integrated with Thinstall and Trigence, but it is not necessary. The executable file can be put on a thumb drive, shared disk space or a CD-ROM.
Before you install
One of the key considerations for choosing an application virtualization vendor is to understand how the company handles the management of the applications that are being virtualized. Not all application virtualization technologies come with a management tool; some companies may require that you buy their management console or management suite in order to use their virtualization solution.
You also must take licensing options into consideration. For example, IT shops have to buy Microsoft's licensing maintenance plan, Software Assurance, on all Windows desktops in order to use SoftGrid.
Altiris and Citrix Presentation Server 4.5 have their own management console, as does Microsoft, via its System Center Configuration Manager. Thinstall's technology can be integrated with LANDesk Software's management suite.
Virtualization also opens IT shops to a whole new management model. "It's like Pandora's Box. No one really knows what kind of management issues are going to come out," said Mark Margevicius, a research vice president at Gartner Inc., the Stamford, Conn.-based consultancy. "No one knows yet how to control virtualized applications and how they fit in with managing their installed base."
IT shops also need to look toward the future to ensure that the technology can integrate with other types of virtualized environments, said Chris Wolf, an analyst with Midvale, Utah-based Burton Group.
Desktop virtualization, in which an entire desktop or OS image is virtualized on the workstation or a server, versus a single application, is a technology to keep in mind. VMware Inc., Citrix Systems Inc. and Pano Logic Inc. are a few software companies who play in this world.
"Looking out, companies are going to want anywhere access to an entire virtual desktop," Wolf said. "[They want] a secure desktop with all the related applications users need, with no downloads, but streamed to the user or an isolated desktop."
Security provisions may settle virtual technology choice
Keep in mind that the security policies you have in place may ultimately decide which technology you deploy.
Financial services companies and government agencies, for example, are opting to go with application virtualization technology that does not require a client-side agent, said Ty Schwab, lead consultant and CEO of virtualization systems integrator Blackhawk Technology Consulting.
"IT shops with heightened security won't allow a client-side agent because that agent scans the system," Schwab said.