ENTERA DCE-CORBA BRIDGE


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Extending DCE and Entera Systems to CORBA and the Web

Introduction -- The Need to Extend DCE Systems to CORBA and the Web

Large organizations have long realized that to maintain a sustainable competitive advantage, they need to extend and integrate their legacy systems to support changing business strategies. They need to make the information from all of these systems available to decision makers in an easy to use and timely fashion. And they need to develop and deploy IT systems and services quickly to respond to rapidly changing business conditions. Many of these organizations have turned to the Open Group's (formerly the Open Software Foundation's) Distributed Computing Environment (OSF DCE) with its Remote Procedure Call (RPC) communications service to integrate their distributed enterprise-wide systems and to make information available to decision makers. And many are using Borland's Entera development environment to radically speed development, deployment, and management of these applications.

Over the past few years, however, changes have occurred in both the business and the technology spheres that are causing organizations to look for ways to extend the capabilities of their DCE systems. The primary motivation is the emergence of the Internet as a key component of many organizations' business models. Companies are using the Internet, intranets, and extranets to provide everything from self-service online sales to 24 x 7 customer support to supply chain integration. Another factor is the emergence of modern distributed infrastructures that enable object-oriented development and Internet TCP/IP communications such as the Object Management Group's Common Object Request Broker Architecture (OMG's CORBA) with its Internet Inter-ORB Protocol (IIOP). It is this type of object-oriented distributed infrastructure that organizations are migrating to in order to build their Internet, intranet, and extranet applications.

As these Web applications have become more robust and mission-critical, there is an increasing need for companies to rapidly and seamlessly connect their new CORBA applications and clients to existing production applications that support DCE. Such interoperable systems, for example, allow for smoother electronic commerce applications by allowing customers to place their own orders directly into an organization's order entry system, or to make it easier for partner organizations to share the manufacturing and logistics information necessary for an extranet application that enables just-in-time manufacturing.

The Borland DCE-CORBA Bridge is one of the first products available to seamlessly and transparently connect the CORBA and DCE environments. With this gateway product, organizations can now:

With the Borland DCE-CORBA Bridge, organizations can leverage their current investment in existing Entera and DCE applications while laying a solid foundation for expansion of those systems onto the Internet. This White Paper details how the DCE-CORBA Bridge can provide these advantages to your organization.

DCE offers a proven, vendor-neutral computing infrastructure

Introduced ten years ago, the OSF DCE distributed computing framework is currently in use by organizations in areas such as telecommunications, government, financial services, and industrial firms for everything from supply chain management to industrial process control to human resources to product distribution. OSF DCE is a robust vendor-neutral standard that provides the foundation for architecting multi-tiered client/server applications that allow mainframes, workstations, and all types of client/server systems to work together easily. The DCE infrastructure provides the essential distributed computing services necessary to address today's pressing integration requirements. These services include a directory service that can locate entities anywhere throughout the enterprise, a security service providing authentication, authorization, and encryption services, and the Remote Procedure Call (RPC) communications service that allows users and applications to communicate with other applications or to access data throughout the enterprise. DCE's interface definition language (IDL) defines interfaces to the RPC service.

DCE allows organizations to deploy application components across multiple systems, enabling better resource utilization and enhancing scalability of applications. The robust infrastructure allows users to transparently access information systems anywhere across the enterprise, and yet ensures corporate security. And it enables application systems to be flexible and extensible.

Entera makes DCE development easy
Because DCE application development is complex, many organizations are using Borland's Entera product as their Rapid Application Development (RAD) environment of choice for DCE-based multi-tiered client/server applications. Entera conceals the complexity of middleware programming, allowing corporate IS to focus on quickly developing business applications, increasing application productivity, and providing a quick return on investment.

CORBA extends the integrated enterprise to the Internet

With the emergence of the Internet and reliable electronic commerce applications, organizations are now building mission-critical applications for deployment on the Web. And they are using object-oriented distributed application frameworks such as CORBA to do so. In addition to providing many of the benefits offered in DCE, object-oriented systems simplify application development and modification through object encapsulation, which allows developers to change the implementation of an object without affecting any other objects.

As a result, the object-oriented middleware market, which currently stands at $196.8 million, according to an April 1998 report by the International Data Corporation, is expected to grow by 35% in 1999, and by an additional 33% in the year 2000. Widely supported by vendors such as Netscape, Sun, and Oracle in their next-generation products, the OMG's object-oriented CORBA framework is rapidly becoming the middleware technology of choice for developing these modern distributed Internet, intranet, and extranet applications. The reason is that CORBA is the only object-oriented framework designed from the start to support heterogeneous distributed systems.

The CORBA specification describes a software bus, called an Object Request Broker (ORB) that provides an infrastructure for distributed object computing. The ORB enables client applications to communicate with remote objects, invoking operations either statically or dynamically. The CORBA 2.0 specification includes a protocol for ORB interoperabilty called the Internet Inter-ORB Protocol (IIOP). IIOP is robust, scalable, and transaction-oriented. It runs on top of TCP/IP, requires no special configuration, and is fast becoming the standard for communication between and among distributed objects running on the Internet and enterprise objects.

The ORB backbone is extended with modular, add-on, system-level services that complement the functionality of the ORB and provide building blocks for business applications. These services include a naming service that enables objects to find each other by name, an event service that enables objects to subscribe to an event channel to be notified of specific events, a transaction service that defines transactional disciplines, coordinating two-phase commits among objects, and a security service. Because CORBA is a relatively new standard, however, many of these services, notably security, do not offer the same robust functionality found in the older DCE standard.

Requirements for integrating Entera/DCE and CORBA

As organizations move to expand their Entera and DCE-based business applications to incorporate the World Wide Web, they are thus likely to use CORBA-based applications to do so. But they are also looking for a way to build a bridge between their CORBA applications and their Entera and DCE systems in a way that:

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