OpenDoc: A Better OLE than OLE?

Robert L. Hummel

Among Windows software developers, Microsoft's Object Linking and Embedding technology is the standard for interapplication communication. One of OLE's strengths is its tight integration with the underlying Windows architecture. But the Windows-dependent nature of OLE has opened a window of opportunity for a new architecture.

OpenDoc is attracting attention as a cross-platform component technology. (See "OpenDoc Says OLE to Developers" in the Core Technologies section.) Control of OpenDoc standards has been invested in Component Integration Labs, a nonprofit industry consortium founded by Apple, IBM, and Novell. And OpenDoc has recently been incorporated into the Common Object Request Broker Architecture (CORBA) standard.

App le was first to deliver OpenDoc, shipping version 1.0 for the Mac OS in 1995. But although Mac developers are interested in OpenDoc, many are taking a wait-and-see attitude, says Stefan Wennik, manager of marketing and communication at Bitstream (Cambridge, MA). "When we talk to Macintosh developers and ask if they need our products as OpenDoc components, we get blank stares," Wennik said. "We love the idea, but I don't think anyone needs this stuff in a big way right now."

Mac developers are interested in OpenDoc, but there's currently little incentive to support it, according to Karl Cremin, senior analyst at MindShare. "To the end user, the value of an OpenDoc component is being able to use it in an application," Cremin said. "Support in big applications is the key to OpenDoc's success among Mac developers."

Converting Mac developers to OpenDoc is not enough to establish a cross-platform standard. IBM recognizes this and now offers OpenDoc for OS/2 3.0, with versions for AIX (currently in bet a) and Win 95 and NT (to enter beta in June) expected to ship later this year. IBM will make the Windows OpenDoc toolkits available for free downloading at http://www.software.ibm.com/clubopendoc .

IBM is implementing OpenDoc under Windows in part to woo OLE developers. But IBM is attempting to underplay the idea of a face-off between OpenDoc and OLE. "We're not saying, `Don't do OLE,"' says Scott Hebner, manager of OpenDoc marketing development at IBM. "Instead, we're saying that OpenDoc provides a much better way to build OLE into your Windows applications."

Hebner admits that developers creating applications exclusively for single-user Windows platforms gain little by embracing OpenDoc. But for cross-platform applications, using OpenDoc to implement OLE greatly increases the services available to an application, he says.

To complicate choices even further, the chances that OLE may be available on different platforms is definitely increasing. Bristol Technology (Ridgefield, CT, 203-438-6969, http://www.bristol.com ), a strategic partner with Microsoft, is now shipping its Wind/U Win32 cross-platform development kit. Appearing as a set of shared libraries, the new Bristol product makes OLE functionality a reality under Unix.

"OLE has become so easy to use," said Ken Blackwell, chief technical officer at Bristol, "that it's now an integral part of most Windows applications. Commenting out the OLE code when porting to Unix, a common practice in the past, is simply no longer practical." For Windows developers, Blackwell noted, OpenDoc is a future target, whereas OLE is something they've grown up with. By providing OLE under Unix, he added, there's nothing for them to relearn.

Another contender is Next Software (Redwood City, CA), which has developed products that integrate OLE and CORBA. "Customers building multitiered cross-platform applications also have to integrate CORBA to OLE," says David Butler, Next's director of enterprise product marketing. "Our D'OLE and PDO products provide object model independence and enable that integration." D'OLE, available now for NT, will support Win 95 this summer. And Next's offerings support versions of Unix from Sun, Digital, and HP, not just IBM's AIX.

Whether a single object architecture will dominate remains to be seen. Mac developers are apt to embrace OpenDoc; Windows developers continue to evolve with OLE. Developers may have to accommodate more than one standard.