Apps on the Fly
For years the infotech industry has been predicting that wireless handheld devices would soon be as versatile as desktop computers. But the best handhelds on the market still don’t come with enough memory to store the average Web browser, let alone Microsoft Office.
Fortunately, they may not have to. A technique called “application streaming” could allow Palm Pilots and cell phones connected to wireless networks to run large applications without storing the software locally. It’s an updated version of the old mainframe network design, with programs residing on a central server, accessed from “dumb terminals” with very little computational power of their own. A handful of firms already market the technology for desktop computer networks and are working on versions for handheld devices, which they hope wireless service providers will adopt within a year. The results could include anything from writing a grocery list on a cell phone to editing an Excel spreadsheet on a Palm Pilot-and sending it off as an e-mail attachment.
The technique can work in a couple different ways. Citrix Systems of Fort Lauderdale, FL, for instance, saddles network servers with all of an application’s computational work, so that, according to senior product manager Steve Piper, “only the screen image is compressed and sent down to the client device,” and “only clicks and keystrokes are sent back up.” But even though compressed screen images and keystrokes require very little bandwidth individually, under the Citrix system they still shuttle back and forth almost constantly; it will take a pretty powerful bank of servers to keep up.
The competing approach is to break applications down into component parts and send users only the components they need at a given time. Of course, it isn’t easy to figure out which components those are. Palo Alto, CA-based AppStream attempts to predict users’ needs on the basis of past decisions; while Nortel Networks Application Management Solutions of Chelmsford, MA, hopes that, by breaking applications into small enough chunks, they’ll be able to “see what the running application asks for and provide it on demand,” says vice president of marketing Jon Friedman.
The companies also differ in the kinds of software they can stream. AppStream, for instance, has concentrated on applications written in the Java programming language-which is quickly becoming the dominant format for wireless applications in Japan. According to vice president of wireless business development Gerald Wluka, AppStream is pursuing several licensing agreements and should have its products installed on wireless network servers in about a year. In addition to Java-based chat, e-mail and video-game programs like those already popular in Japan, the AppStream technology should provide cell-phone users with continuous networked services-like scrolling sports scores or stock prices-and richer interactive interfaces for shopping or searching databases over the Web.
Nortel, on the other hand, is focusing on Windows-based software. According to Friedman, the company expects to release products designed for Windows CE-the Windows operating system for wireless devices-by the end of the year. Although the Nortel system could, in principle, work with any Windows application, Friedman anticipates that “providers will want to rewrite their programs” to accommodate the memory and bandwidth constraints of wireless networks.
As for Citrix, its technology requires that users load their handhelds with a program that funnels screen images down from the server. Piper says that program currently “supports dozens of handheld devices.” At the beginning of this year, several companies in the United States and Europe began using the Citrix system to stream applications to personal digital assistants over local-area networks; and in March, Motorola signed a licensing agreement to incorporate the Citrix technology into its handheld devices.
To some extent, the different approaches are based on different market expectations. AppStream’s Wluka envisions that, when you turn on your Java-enabled cell phone, you’ll see a menu of different features that come with your wireless service package. Some, which you use frequently, will be stored locally; others will be stored on a network server-but you’ll never know the difference. Citrix, on the other hand, promotes its technology as providing “wireless computing users with access to the same rich, full-featured applications they work with at the office.”
The ability to do office work anywhere you can carry a Palm Pilot? Sounds like paradise.
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