Road warriors have never been a perfect fit for Citrix Systems' server-based applications because they require continuous connectivity. But in a software upgrade to be announced next week, Citrix is adding application streaming capabilities designed to help cut the umbilical cord between users and servers.

Citrix officials said Presentation Server 4.5 can offload processing work from a server to a laptop or, for that matter, to a desktop PC. Thus, mobile users can disconnect their systems from a Citrix server but still get full functionality.

The ability to shift some processing to PCs may also let IT managers increase the number of Citrix users per server. At least that's the hope of Susan Paul, IT director at health care provider, Fallon Clinic.

Fallon currently runs clinical applications on 35 Citrix servers supporting about 50 users each. Paul wants to use Citrix's software to run business applications for 300 to 500 new users.

She said the application streaming capability should enable her to more than double the number of clients she now has per server.

"We can move more people over to Citrix without necessarily having to severely beef up our Citrix farm," Paul said.

With streaming, an application sent to a user's system is held in an "isolation container" on the device itself, said Dave Roussain, vice president of product marketing at Citrix.

Even if the system is rebooted, the application remains in place. But IT administrators have control over it, and if an application is updated on a server, the update is sent to each client, Roussain said.

Other major IT vendors have also become interested in streaming technology, which offers security improvements compared with running applications locally on laptops.

Late last month, Symantec announced plans to buy Altiris, an application streaming and management vendor. Microsoft already offers an application streaming product called SoftGrid, which it acquired when it bought Softricity last July.

"Security and remote access is a huge pain point for enterprises," said Natalie Lambert, an analyst at Forrester Research.

"If you want to talk about the future of the computer world, it is this ability to securely deploy and manage [applications]."

Andrew Jurczyk, CIO at Sonnenschein Nath & Rosenthal LLP, said the law firm uses Citrix's software to support lawyers who travel worldwide and are "not always in a connected state." And in some cities, the law firm sets up what it calls a "war room" in hotels that lawyers use to manage cases.

The staffers in the war rooms may need access to additional applications as they work on a case, Jurczyk said.

He now hopes that he'll be able to deliver new applications to the remote workers via Citrix's streaming technology.

"It's like that missing piece," Jurczyk said. "Mobility is a very big part of our solution and strategy."