DCOM Connector for SAP

SAP is a proprietary system designed to run line-of-business applications to manage a large variety business functions. This means that users must work with proprietary interfaces to manage SAP data. SAP, which is an integrated product, allows corporations to graphically map and manage their business processes into an integrated whole.

One of the latest versions of SAP, R/3, is object oriented. This allows SAP system designers to create COM interfaces to support a variety of programmable interfaces supported by COM via the DCOM Connector for SAP. The DCOM Connector for SAP aids in integrating the functionality contained in distributed environments.

The run-time instances of business objects or remote functions provided in the R/3 application are available in MTS as COM objects using the DCOM Connector. The DCOM Connector is installed in the MTS in the form of components within a package and allows developers to create and administer COM objects.

The SAP R/3 DCOM connector is fashioned around the multi-service layer architecture and contains an R/3 application server that exposes the SAP business objects and remote functions that can be called from components within MTS. These objects and functions are mapped through COM via a DLL. Clients can make calls to those components through MTS, which communicates with the R/3 application server and makes the communication transparent to the client application.

In the DCOM Component Connector, ABAP objects (BAPIs) are mapped onto COM interfaces and visa versa. (ABAP stands for Advanced Business Application Programming Interface.) BAPIs is a term used to represent objects that have a guarantee not to change. It stands for a well-defined interface to processes and data of business application systems. Also, the SAP Business Object Repository (BOR) is integrated with the Microsoft Repository (XML Repositories). The solution is scalable because the components can be installed and distributed as often as needed and connections are pooled to R/3's Remote Function Calls (RFCs). When Windows NT clients are used, security is provided in the context of MTS. Optionally, Windows NT user IDs can be mapped to R/3 security for a single logon. All Tables and Structures are represented as ADO recordsets. There is automatic marshaling via RDS. At the core, OLE DB is used to and from map ABAP tables. ADO is the interface to OLE DB. The DCOM Connector automatically generates proxy and stub components for objects. The next version of the DCOM Connector will support 2PC and outbound calls, and requires COM+ Services.

The DCOM Component Connector provides the following benefits for corporations:

• A new dimension of openness The DCOM Component Connector provides interoperability between R/3 objects and COM objects across a hetero-geneous network through well-defined business interfaces. It exposes R/3's mature business processes and business objects to open DCOM access, making it easier to complement and extend R/3 using Microsoft tools—for example, to create new front ends or to extended business processes.
• Leverage existing programming skills With the DCOM Component Connector, developers have the choice of either extending the Business Framework by using software components written with SAP tools (ABAP Objects) or COM tools (Visual Studio, Visual Basic, Visual C++, and Visual J++). This leverages existing investments in training, people, and in the huge market for pre-built COM components.
• Eased integration The integration of R/3 Business Components with third-party products, legacy systems, and homegrown applications has become much easier with the DCOM Component Connector. Now even distributed transactions of several systems containing several databases are possible.
• Evolutionary approach The DCOM Component Connector works even if R/3 itself does not run on a Windows NT platform. This allows corporations to save costs by leveraging their existing infrastructure. And through the built-in scalability of multiple servers in every service layer (MTS and R/3 Application Server), this solution is able to grow with developers' needs.