In-Depth

Distributed object computing: The brave new world

The big competition for Corba then was the Open Software Foundation (OSF), with its Distributed Computing Environment (DCE) standard. Meanwhile, Microsoft was not really in the DOC game at all, other than making some vague statements about how their new operating system still in development and, code-named Cairo, would finally get some real object-oriented features, including the yet-unspecified Component Object Model (COM).

A long way baby

No one can seriously deny that DOC has come a long way since then. This year, the OMG has grown to over 700 members, and a fully interoperable Corba, joined at the hip with Java, is making its debut on the Internet. The OSF has nearly vanished, and Corba companies like BEA Systems Inc., Sunnyvale, Calif., Iona Technologies Inc., Dublin, Ireland, and Visigenic Software Inc., San Mateo, Calif., that are selling Corba technologies are becoming the new high-tech darlings of Wall Street.

Meanwhile, Microsoft has released Distributed COM (DCOM), and is touting its new object Transaction Manager, previously code-named Viper, which even Microsoft now describes as an an Object Request Broker (ORB), just like OMG's Corba. Oddly enough, DCE is now mainly an under-the-covers way to implement DCOM, and Cairo is once again just a big city in Egypt (or, if you prefer, a small town at the southern tip of Illinois).

Now the question is no longer whether DOC will become the backbone of global distributed computing, but just how -- and how soon. Vendors and consultants are frantically trying to put together their DOC strategies, while end users are tire-kicking Corba and DCOM in droves and asking questions about the ROI on large-scale DOC projects. (See Fig. 1.)

Fig. 1: ORB usage -- then and now

The world of distributed object computing (DOC) has expanded from making the OMG's Corba and the OSF minimally interoperable to the now interworking Corba and Microsoft's DCOM.

Source: Genesis Development Corp.

Yesterday's news

But that's just yesterday's news. The really late-breaking story is just starting to gel as a whole new approach to DOC is shaping up around the not-so-new concept known as 'business objects.' A more proper name is probably 'domain objects,' but the term 'business objects' better catches the spirit of this trend and has been in use throughout the industry for longer.

In short, a business object is a self-managing component that represents a key business entity or process intended to be (re)used all over an enterprise, or even across related enterprises. Conceptually, the notion of a business object is the Rosetta stone of business computing -- it's the first time that the same concept can be used to both describe a piece of the business and an executing piece of the information system that supports that piece of the business.

This advance is a tremendous help to those folks who have been struggling with business process modeling and (re)engineering. Previously, businesses that engaged in such modeling exercises reached a no-man's land when they tried to convert their reengineering results into new software. The paradigms for expressing business models and software models were miles apart, and only a few very expensive and complicated CASE tools even tried to bridge the gap -- with very limited results.

Fig. 2: Mapping ORBs and business models


In this approach to logically mapping ORBs and business models, the output of business modeling is a set of high-level business components configured to run directly as distributed objects on an enterprise ORB.

Source: Genesis Development Corp.

In the new approach, the output of business modeling is a set of high-level business components, which can then be configured to run directly as distributed objects on an enterprise ORB. After that, any business event in the real world, like the placing of a new order, simply becomes the construction of a new business object (an 'order') that then assumes an identity and life cycle of its own, supported by the enterprise ORB. (See Fig. 2.)

This represents a huge step up for DOC, which previously was positioned as specialized plumbing for exotic forms of client/server computing.

This earlier positioning relegated DOC vendors to selling their wares mostly to distributed computing "techno-dweebs" working on a few very leading-edge projects. With business objects, however, DOC suddenly becomes a major technology enabler for business, with a broad target market leading right into the office of every major CIO and CEO.

Even better, the upcoming blitzkrieg of DOC-enabled business objects already has its path cleared in advance by today's number one technological buzz-bomb, the Internet. Basically, what the Internet and its variations -- Intranet, Extranet and the like -- have done is to knock down almost all the remaining artificial and realistic barriers that once kept everyone stranded on their own proprietary 'islands' of computing.

Now, every I/S manager is on notice that the business may demand that almost any system, even those dark and dirty legacy dungeons, may one day need to be seen from almost anywhere else in the world to meet the insatiable demand for electronic commerce. Just how insatiable is this demand for global accessibility? To find out, take a moment to read the neighboring excerpt. (See "A Virtual Fable.")

But, as we all know, today's Internet technology is not really up to that kind of demand. Today, most companies are still struggling just to develop and maintain relatively simple Internet sites, while maintaining appropriate security and integrity for their underlying systems. They are doing this largely because the most popular Internet protocols, such as -- HTTP and CGI, etc. -- were never really designed for the kind of applications now being demanded by business as commonplace on the Internet, much less full-blown global electronic commerce.

However, what is a meltdown for conventional Internet techniques is simply critical mass for DOC. Real DOC protocols like Corba and DCOM, combined with business objects, have the potential to handle not only the peak loads of today's Internet, but also the truly high-volume, high-performance demands of tomorrow's Internet successor -- the global electronic commerce machine we have begun to call the 'Meganet.'

Mining the Meganet

How will the brave new world of the DOC Meganet work? Businesses would make their basic commercial interfaces -- checking inventory, estimating costs, accepting orders and payment and so on -- visible to potential clients through business object interfaces described in some kind of standard business object interface definition language (IDL), hosted by a standard ORB. The ORB would also host the implementations of those business objects, but these implementations would, of course, remain completely opaque to any clients.

Each hosting ORB would be connected through a standard inter-ORB protocol like OMG's Corba Internet Interoperability Protocol (Corba-IIOP) to all other ORBs through the Meganet. This would allow any ORB-enabled client to access any ORB-based business object anywhere in the world, at any time, based, of course, on suitable authorizations. (See Fig. 3.) The various ORBs on the Meganet -- Corba, DCOM and/or their successors -- would handle the necessary global request brokering, security, transaction management, concurrency control and exception handling.

Fig. 3: ORBs and business objects coexist

Through the DOC Meganet, each hosting ORB would be connected through an inter-ORB protocol, like OMG's Corba Internet Interoperability Protocol (Corba-IIOP), to all other ORBs.

Source: Genesis Development Corp.

The business implications of this are staggering. The simple-minded Internet servers of today only talk directly to end users with visual browsers, plunking along page by page and they have to be gerry-rigged to support even simple-minded business transactions. On the Meganet, however, servers will be serving up real distributed objects, which can engage in arbitrarily complex transactions with other objects. This puts the kind of business-to-business electronic commerce described in "A Virtual Fable" much closer.

If you think the Meganet itself is still far off, guess again. Within a few months, every Netscape browser and server in the world will support Corba-IIOP, not to mention the platforms of almost every other major vendor, including Sun Microsystems Inc., Mountain View, Calif., Novell Inc., Provo, Utah, and IBM. Meanwhile, every Microsoft software platform will support DCOM. But, lest you worry that a market fight between Corba and DCOM might leave the Meganet in tatters, be forewarned that there is already a working, commercial standard for Corba/COM inter-networking, supported by both that will handily support the coming Meganet.

In any case, the certain winner of any upcoming 'battle of the business object Meganet' will be the businesses of tomorrow, and with them, DOC. While there are certainly many details yet to be ironed out, there is absoluutely no question that there will be such a Meganet, and that it will run on some kind of DOC engine -- Corba, DCOM or some hybrid successor. If so, this means that, in short order, the commercial battle lines will be moving elsewhere. Where? Some experts believe they are in fact already moving four-square towards business objects themselves.

Making business objects viable

To learn how business objects will cavort across tomorrow's Meganet, there is probably no better example than the OMG. The OMG may not be the only place that DOC and Meganet history is being made, but, with its open process, the OMG standards group is definitely one of the best places to see it unfold.

Last year, the OMG opened its doors wide to corporate end users, who are flocking to form new working groups and task forces to define global DOC standards in such business domains as finance, telecommunications, insurance, manufacturing, transport and medical systems. This is a huge step forward for the OMG, which previously limited its efforts to standardizing generic facilities like ORBs, transaction managers, security services and event managers.

In addition, the OMG is currently involved in developing at least two new standards that are likely to have a major impact on tomorrow's Meganet -- a Business Object Facility (BOF), and a unified Object-Oriented Analysis and Design (OOAD) interchange specification. Together, these new standards, both due out by the end of this year, will form the backbone of both design-time and runtime support for frameworks of distributed business objects, including those based on the domain standards defined earlier. (See Fig. 4.)

Fig. 4: The OMG's structure

These new standards will form the backbone of both design-time and runtime support for frameworks of distributed business objects.

Source: Genesis Development Corp.

Let's first look at the BOF. In short, the goal of the BOF is to make it a lot easier to host over Corba the runtime versions of the kind of domain object models that most business users want. It is no secret that Corba is a very generic standard designed to support virtually any kind of DOC problem. Thus, if you want to host a straightforward business object like SalesOrder directly over Corba, there could be dozens of complex decisions to make about transactions, security, persistence and so on. Such a scenario also requires dealing with many interfaces.

However, a BOF can automate much of the housekeeping chores that would be hand-coded in Corba. Corba would be automatic. In other words, analysts working in some particular line of business could define a high-level business object model, and then use the BOF to host the runtime business objects associated with that model with minimum effort. The BOF itself would use Corba services to manage those objects in a very consistent way.

Since the BOF will be hosted over Corba, and since Corba will soon be all over the Internet, the facility BOF could rapidly become the standard business process for publishing global electronic commerce interfaces. Once these interfaces become standardized, the makings of the Meganet will truly arrive, and the 'Virtual Fable' will be a fable no more.

Using the BOF will be even easier when OMG completes the standardization of interchange formats among various OOAD tool vendors. These tools typically provide a means for capturing domain object models, displaying the models graphically and maintaining various forms that support documentation. Some tools can also generate and/or reverse engineer C++, Smalltalk and Java code. Until recently, each tool stored their models in a highly proprietary format that made exchanging or sharing models among different tools very difficult.

OMG is now involved in a major effort to create a notational Rosetta stone to be supported by every OOAD tool. (See "Converging on OOAD Agreement" by Viktor Ohnjec, Application Development Trends, February, 1997.).

This is good news in any case, but it is particularly convenient for the BOF. Once all OOAD tools can read and write in a common format, all the information can also be shared with the BOF, which can use it at runtime to manage the various business objects that are created. Such a standard could become another point of convergence for OMG and Microsoft. That's because Microsoft, which previously had no apparent OOAD tools strategy, recently announced a strategic alliance pact with Rational Software Corp., Santa Clara, Calif., a maker of several object-oriented tools. In addition, Microsoft has agreed to support Rational's proposed OMG standard for OOAD tools.

Distributed-object computing opens up a host of new activities in addition to the technology areas mentioned (DCOM, Corba, BOF, OOAD, etc.). Specifically, vendors are beginning to move toward integrated solutions. (Rational is working with Microsoft and has acquired several companies in recent months, most notably Pure Atria, Sunnyvale, Calif., and Software Quality Automation, Burlington, Mass.) Meanwhile, Platinum Technology Inc., Oakbrook Terrace, Ill., is integrating myriad acquired solutions. Sterling Software Inc., Dallas, has recently acquired Texas Instruments Inc., Plano, Texas, whose high-end tools will be merged with the offerings from Sterling's Atlanta-based development tool unit. Although many of the buzzwords change -- like business objects and component-based development, etc. -- the expectations of DOC remain.

With the move to components and business objects, however, some suppliers are also introducing development tools that can leverage existing legacy systems and approaches in distributed business applications. Cambridge, Mass.-based Riverton Software Corp.'s HOW product, for instance, lets developers custom build -- or adopt and extend -- business objects and technology components to produce applications that are partitioned along presentation, business logic and data access boundaries. Such tools were unheard of even a couple of years ago. The likelihood today is that more and more of these tools will emerge as BOF and OOAD maturity increases.

As the details behind the BOF and OOAD specifications become solidified later this year, a path will have been be cleared for the various industry-specific groups to deliver specifications for their respective domain object models. Those models, specified in the OMG standard OOAD notation, can then be expected to run over an OMG standard BOF with appropriate ORB support. When BOFs become widely available, and as the domain models become mature, the incredible commercial possibilities of DOC distrobuted object computing and the Meganet will start to become obvious to everyone.

The world is changing, and DOC is tracking that change.