Up-to-date data always available

An increasing number of companies will invest in SAP NetWeaver as a strategic platform in the next few years. In contrast, SAP applications are far from being deployed in all company departments. A large number of companies still run applications in mainframe and Unix environments, especially in the back-office. And although key business processes frequently run on these systems, these legacy applications are generally not integrated in SAP-based business processes. Data from these legacy applications are not directly available in the SAP applications environment and business processes throughout the company do not extend across all systems. To integrate the different system landscapes, data is exchanged through a whole host of specific interfaces.
An example from the insurance industry shows why data still often has to be exchanged in this way. A customer took out life insurance at the start of the 1990s. The policy data is on an isolated mainframe where the system architecture dates from the 1980s. Now, the service employee on a customer visit wishes to access the master data online via a notebook and change the term of the policy. As the mainframe is not directly integrated to the Internet for technical reasons, communication has to be performed indirectly via a web application server upstream, which updates the data in a separate batch process on the host.
In all, this is a very time-consuming method that raises data security and integrity issues. Nor can Internet connection stability always be guaranteed in such situations. For cost considerations, migration of legacy applications to SAP solutions is in many cases not a suitable alternative either.

The alternative: XI adapters

One possible solution to integrate legacy applications in new SAP NetWeaver-based architectures and accelerate business processes comes in the form of adapters integrated in the runtime environment of SAP NetWeaver Exchange Infrastructure (SAP NetWeaver XI) – an essential component of the SAP NetWeaver platform. In this way, companies protect their investments in transaction-supported, high performance corporate environments and can harness the full potential of their legacy applications for all business processes in the company.
The demands on XI adapters are high. First of all, they should support as many legacy application platforms as possible, e.g. mainframe environments such as VSE, z/OS and OS/400, as well as UNIX and Windows systems. They must also be able to integrate applications written in various programming languages. These include COBOL, Natural, PL/1, RPG, C, Assembler, .NET, and Java.

Communication is not a one-way street

One example of a solution that integrates legacy applications in SAP’s Exchange Infrastructure (SAP NetWeaver XI) is the ‘Legacy Integrator for SAP NetWeaver’ from Software AG. It consists of a number of individual components from which the ‘XI adapter for EntireX’ and ‘XI adapter for Natural’ have been certified by SAP.
XI adapters are based on an SAP NetWeaver Exchange Infrastructure adapter engine. Mainframe applications employ this technological basis to communicate with the XI adapters via a TCP/IP-based RPC protocol. The adapters also automatically transform the data from the format of the legacy application to the SAP NetWeaver XI format. If an XI adapter receives a message from an SAP application, it is converted into the format specific to the legacy application, processed there, and sent back to the XI adapter, where the message is converted into the SAP NetWeaver XI message format – i.e. into XML data. Software AG’s XI adapters can both send and receive data, data being exchanged in both directions in real time. In this way, changes to data in the SAP application automatically initiate communication with legacy systems via the XI infrastructure. It is also possible for a legacy application to initiate XI communication as an XI client. The XI adapter technology therefore ensures that relevant company data is always correct and up-to-date in different IT systems.

Central monitoring not confined to adapters

Seamless integration of XI adapters in SAP NetWeaver XI also pays dividends for system management. With ‘Legacy Integrator’ for integration with SAP NetWeaver, standard monitoring tools from SAP NetWeaver XI, such as Runtime Workbench, assume all monitoring functions for legacy environments too. These include monitoring the adapters and dependent communication channels, performance monitoring, determining volumes, and analyzing messages in detail. Irregularities in integrating legacy applications can therefore be analyzed precisely, which is also an important prerequisite for integrating mission-critical legacy systems.

Effective interplay with SAP NetWeaver XI

‘Legacy Integrator’ for integration with SAP NetWeaver is based on open standards and can be installed fast and easily via SAP NetWeaver’s Software Deployment Manager (SDM). The integration software is closely integrated with SAP NetWeaver Exchange Infrastructure and uses SAP NetWeaver XI tools and concepts, thereby ensuring effective integration and communication. XI adapters are registered via SAP NetWeaver’s System Landscape Directory (SLD) and are operated via the adapter framework/adapter engines. The various message types can be defined via the Integration Repository (IR). The integration directory is responsible for configuring the communication channels. Runtime Workbench (RWB) monitors the adapters and applications integrated via adapters.

Benefits for users

An XI adapter-based solution to integrate legacy applications with SAP NetWeaver-based infrastructures benefits companies in many ways. Data from mainframe and other legacy environments is available in SAP applications in real time and can also be condensed into an overall view. Staff, customers or business partners therefore always have up-to-date information – an important contribution to optimizing business processes. Linking the legacy environment to SAP applications also offers significantly enhanced efficiency as administering and configuring them and monitoring performance occur via the central management of the SAP NetWeaver platform. This clearly reduces the complexity of the IT infrastructure and cuts operating costs.
In deploying XI adapters, companies offer themselves a route to step-by-step integration of their legacy world in SAP NetWeaver. The XI adapter therefore helps companies both cut costs and simplify their infrastructure throughout. The adapter is an interesting option for companies wishing to migrate existing interfaces between legacy and SAP applications to SAP NetWeaver. The insurance agent mentioned earlier would also benefit from integration via XI adapters. Legacy data from host applications could be accessed directly and in real time using SAP NetWeaver and Software AG’s XI adapters, allowing better service for the customer and consequently increased sales.

Christian Zimmermann
Christian Zimmermann