Understanding the BEA eLink Solution

 

This section contains the following topics:

• BEA eLink Solution Overview

• BEA eLink Adapter into WebLogic Enterprise CORBA Overview

 

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BEA eLink Solution Overview

BEA eLink^TM provides an open Enterprise Application Integration (EAI) solution that allows applications throughout organizations to communicate seamlessly. Using EAI, you gain the long-term flexibility and investment protection you need to keep up with today's ever-changing business environment.

Typically, companies use packaged applications to automate internal operations, such as financial, manufacturing, or human resources. While they successfully address the needs of these specific areas, these proprietary platforms often do not work together. To compete today, you need a much greater exchange of information. Systems need to communicate at a process level within your own organization, as well as with customer's and supplier's systems. BEA eLink Platform is the underlying basis of BEA eLink, a family of off-the-shelf enterprise application integration (EAI) products. BEA eLink leverages the BEA transaction platform to integrate existing legacy applications with customer-focused and business-to-business e-commerce initiatives.

BEA eLink Platform provides a proven infrastructure for integrating applications within the enterprise and across the Web. BEA eLink Platform ensures high-performance, secure transactions and transparent access to mission-critical applications and information throughout the enterprise and across the Web. Figure 1-1 illustrates the eLink logical architecture and shows where the eLink Adapters fit into the process.

Figure 1-1 BEA eLink Solution Illustration

The entire BEA eLink family (including all options and adapters) is highly scalable. Multiple instances of BEA eLink components can collaborate so that work is divided between eLink domains. BEA eLink includes Simple Network Management Protocol (SNMP) integration for enterprise management.

The current BEA eLink Platform leverages the BEA Tuxedo infrastructure because it is based on a service-oriented architecture. Both BEA Tuxedo and BEA eLink communicate directly with each other and with other applications through the use of services. Multiple services are grouped into "application servers" or "servers". The terms Tuxedo services/servers and eLink services/servers can be used interchangeably. Because this document is specifically addressing the eLink family, the terms "eLink service" and "eLink server" are used throughout.

The BEA eLink Platform complies with the Open Group's X/Open standards including support of the XA standard for two-phase commit processing, the X/Open ATMI API, and XPG standards for language internationalization. C, C++, COBOL, and Java are supported. The BEA eLink Platform connects to any RDBMS, OODBMS, file manager or queue manager, including a supplied XA-compliant queueing subsystem.

The following components operate with BEA eLink Platform:

• The Information Integrator translates data models used by different applications. It provides a cost-effective alternative to writing or generating programs to perform this function. It also handles complex translation with great power and scalability.

• The Business Process Option helps automate tasks in the distributed global business process and dynamically responds to business events and exceptions. The BPO is implemented by integrating eLink with technology based on InConcert workflow management software.

• An eLink Adapter provides the interface between the BEA eLink Platform and external applications with out-of-the-box functionality.

 

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BEA eLink Adapter into WebLogic Enterprise CORBA Overview

The BEA eLink Adapter into WebLogic Enterprise CORBA (hereafter referred to as the eLink Adapter for CORBA) provides communication between WLE CORBA-based applications and applications integrated by the eLink Platform. Access to other CORBA environments is provided through WLE. eLink Adapter for CORBA uses the WLE CORBA IDL entries to generate local, WLE-based services. eLink-based applications make calls into a "remote" service that, in turn invokes a CORBA method and receives return information from the CORBA method.

Note: Third-party CORBA methods can be called indirectly provided that the foreign method is registered with WLE.

To achieve the eLink to CORBA integration, the eLink Adapter for CORBA provides a pre-built WLE object server that exposes the services necessary to represent one or more CORBA interfaces. This server translates an eLink service invocation from the eLink client into CORBA method invocation(s) on the correct CORBA object and returns any results from this invocation. The adapter uses FML32 buffers and supported data types to invoke CORBA object methods. Parameters consisting of structures or objects are not supported.

This communication is made possible using the existing eLink infrastructure and a set of application adapters. The eLink Adapter for CORBA runs within the WLE server application space and answers ATMI service requests initiated from an eLink Platform environment. These service requests can be initiated from within WLE or from a remote Tuxedo or eLink application using Domain Gateways. The eLink Adapter for CORBA provides a gateway to CORBA objects by transforming ATMI service requests to CORBA Object method invocations using the standard CORBA Dynamic Invocation Interface.

Using this adapter in conjunction with the Domains feature, ATMI service calls from anywhere on your TCP/IP network can be allowed access to CORBA objects. A domain is a collection of BEA eLink servers, services, interfaces, machines, and associated resource managers defined by a single UBBCONFIG (ASCII version) or TUXCONFIG (binary version) configuration file.

In the following illustration, a client running on the eLink Platform invokes a method of a CORBA object that returns customer order status.

Figure 1-2 eLink Adapter for CORBA Run-time Components

The eLink Adapter for CORBA determines the eLink business service to CORBA object method mapping via a configuration file. To facilitate creation of this file, the adapter includes command line configuration tools that browse the CORBA object information of the WLE Interface Repository and generate an adapter configuration file and an FML32 Field Table file.

• The CFGEN command line tool browses the CORBA object information in the WLE Interface Repository and generates a configuration file containing configuration parameters for object methods that can be accessed using the adapter.

• The FTGEN command line tool inputs an adapter configuration file along with the Interface Repository to create an FML32 Field Table file. The generated FML32 Field Table contains entries for all fields in the configuration file. FML32 Field Table files are used to define the IDs and types of fields contained in an FML32 buffer.

  Figure 1-3 BEA eLink Adapter for CORBA Configuration Components