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Erp

ERP

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UNIT 4 Description of Our Good Old and Still Great R/3 Previous sections have discussed the use of this software system and who decides to implement it: SAP R/3 or mySAP ERP controls business processes and manages essential company information. Enterprises needing those services implement this standard software. To manage the complex business needs of companies, the SAP product family offers leading technology solutions: Multitier client/server architecture. Based on middleware for supporting open systems technology. Initially based on the Business Framework architecture, then the Internet Business Framework, and now with the Integration platform of SAP Net Weaver, SAP is open to a total integration with other components, applications, systems, or services.  Homogeneous user interface among applications.  Comprehensive development environment.  Total application integration.  Solution Sets for configuring the system.  Wide range of services, including hotline support, training, consulting, quality checks, and so on. Figure 1-10 shows the classical SAP R/3 components from a functional point of view, before the SAP Web AS. The overall SAP R/3 system is represented by everything included inside the ellipse. The lower layer is made of the operating system, the physical database (whose software is normally included in the SAP kit, although licenses can sometimes be negotiated with the DB software vendor), and the network. The middleware layer, which is above it, interfaces with the lower one and integrates the SAP R/3 applications on top of it. This middle layer was known as the basis system and includes components such as the ABAP development workbench, the system administration tools, batch job handling, authorization and security management, and all cross-application modules. ABAP/4 is a fourth-generation programming language that was used to develop all R/3 application modules. When releases 4.0 and 4.5 were introduced and SAP's strategy Began to focus on object orientation, it was decided to rename the programming language to simply ABAP, abandoning the 4 in reference to fourth generation. Chapter 7 gives an overview of the SAP Solutions development components and options, including ABAP. Middleware are the layered software components that facilitate the development of client/server applications that can be deployed in heterogeneous vendor platforms. The basis system, also known as the kernel, is the SAP R/3 middleware. The SAP Web Application Server uses exactly the same concept and components, with the inclusion of an additional and native Internet layer, known as Internet Communication Manager or ICM. The upper layer, the functional layer, contains the different business applications: financial, human resources, sales and distribution, materials management, and so on. The integration of all applications relies on the basis system. SAP defines client/sewer also from a business solution point of view: a technology concept that leverages computing power to link core business processes with software, tying together various functions, such as financial services, human resources, sales and distribution, logistics, and manufacturing. A common way for SAP to illustrate the R/3 system was the one shown earlier in Figure 1-1, with the R/3 kernel system providing the necessary integration and infrastructure for the R/3 applications. The R/3 kernel makes use of standard communications and application program interfaces to access the operating system, the database, and the network. This kernel layer is located below the application logic and data layers of the system and operates independently from the applications. This architecture allows users to change system configuration and install new systems without interrupting or altering the applications themselves. Multitier Client/Server Solutions In general, client/server is a style of computing that distributes the workload of a computer application across several cooperating computer programs. This type of computing separates user-oriented, application, and data management tasks. Client/server is mainly a software concept that includes a set of service providers and service requesters. In client/server computing, individual software components act as service providers, service requesters, or both. These software services communicate with each other via predefined interfaces. With the emergence of the Web and Web standards and the ability to have an Internet browser as user interface, together with the development of the ITS, the classic three tiered client/server architecture became a multitier system. Major advantages of the client/server approach are as follows: 1. Flexible configuration. With the deployment of standard communication interfaces, there are many possibilities for distributing and planning a client/server installation: from a centralized configuration to a highly distributed system. 2. Workload distribution. Because application servers work in parallel and communicate with the database, users can be evenly distributed based on their job tasks. Also, there is the possibility of deploying dedicated application servers to specific business areas. 3. High scalability. Client/server permits users to adapt the capacity of their hardware according to the performance needs of their businesses, such as adding additional application servers when there is an increase in number of users, when additional modules start production, and when the database becomes larger. This enables companies to protect software and hardware investments. One of the widely used client/server configurations with SAP systems is the three-tiered architecture (see Figure 1-12), which separates a system's computers into three function groups: presentation, application, and database. Since client/server is a software concept,it must be clear that an application server includes the software components that make upthe provider services for the presentation, acting as a server, but also acting as service requester of the database services. With the three-tiered architecture, each group is set up to support the demands of its Functions. The central server contains the database, widely known as the database server. Application servers include the processing logic of the system, including services such as spooling, dispatching user requests, and formatting data. The tasks related to presentation of the data are handled by the presentation servers, which typically are personal computers or workstations, enabling easy access to the system. Communication among the three tiers or server types is accomplished with the use of standard protocol services, such as the ones provided by TCP/IP or CPIC. CPIC stands for Common Programming Interface Communication and includes standard functions and services for program-to-program communication with the ABAP programming language. Chapter 2 shows in greater detail the services, processes, and components of the client/server architecture of SAP Systems, and in particular how all this evolved into the SAP Web Application Server technology. Open Technology The key to SAP R/3 success was the strategy of making open solutions, in which the applications can run on multiple operating systems, databases, and communication technologies. This enables customers to remain independent of a single vendor if they wish. The list of current SAP-supported systems can be found also on the SAP Service Marketplace in their Platform link (currently in service.sap.com/platform, but watch for updates). What basically makes systems open is the use of standard formats for data exchange, communication interfaces, and program-to-program communication. SAP extends the openness concept in several respects: At the system level. Support for multiple hardware platforms and operating systems, such as all types of UNIX from main system vendors, Microsoft Windows platforms, AS/400, OS/390, and Linux. Support for a large number of graphical user interfaces (GUIs), such as for all Windows flavors (currently only Windows 32 bits are supported), Macintosh, Internet Browsers, JavaGUI, and so on. At the database level. R/3 supports various relational database systems such as Oracle, Informix, SAP-DB or mySQL (MaxDB), DB2, and Microsoft SQLServer. Access to the data managed by SAP R/3 is possible using standard R/3 reports as well as any other SQL standard tool: ODBC, SQL browsers, and so on. SAP has incorporated the standard ANSI-SQL as the database manipulation language, which allows users and programmers to store, view, and retrieve data to and from all different underlying database products. At the application level. The system is open to be enhanced and extended to meet specific business requirements. This can be accomplished either using the ABAP repository and development environment or currently all the facilities provided by the tools and development environment enabled by SAP Net Weaver components. On the foundations, SAP R/3 programming interface lets other SAP systems and external programs invoke SAP function modules via RFCs (remote function calls) or RPCs (remote procedure calls), using Business Application Program Interfaces (BAPIs), and all new types of interfaces enabled by the Business Framework and the Internet Business Framework (DCOM, Java Connector, Business Connector,etc.). At the URL http://ifr.sap.com (SAP Interface Repository), there is a comprehensive collection of all interface and interface types that can be used to access or exchange information with SAP systems, using different methods, and classified by application components and interface types. At the desktop level. With the initial deployment of Microsoft OLE (Object Linking and Embedding) technology, then with COM and now with .NET, SAP systems enables desktop users to access SAP data and functions from many Windows client programs. With the introduction of SAP R/3 release 4.0 and especially with 4.5 and 4.6, SAP leveraged the concept of integration with PC programs, mainly with the technology provided by ActiveX and Java. At the communication protocol level. SAP can use the standard communication protocols TCP/IP, SNA-LU6.2, CPIC, and HTTP for interprogram communications as well as for network communication and data transfer. Since SAP Web Application Server 6.10, support for HTTP/HTTPS is native in the system. At the external communication level. Since release 3.0, SAP systems have included support for EDI (Electronic Data Interchange) interfaces to automate the exchange of data (invoices, orders, etc.) between SAP systems and other applications systems used by business partners. It also uses MAPI (Messaging Application Program Interface) technology, supporting standard X.400 and SMTP protocols. These standards allow R/3 users to communicate with other mail systems and the Internet. With the SAP Web Application Server, SMTP is now native in the system without the need to install or set up e-mail gateways or additional connectors, and lets the SAP system act as an MTA (Message Transfer Agent). Since release 3.1, with the incorporation of the BAPI technology, SAP has actively supported the new electronic commerce technology with the deployment of the Internet, which allows business transactions to happen between Internet users and SAP systems. Many of the new interface types and data exchange standards are still based on BAPIs. With the ALE (Application Link Enabled) technology, SAP allows communication between distributed applications: between SAP systems and between SAP and external application systems. Using development languages such as standard ANSI C, C++, Java, Delphi, Visual Basic, and the newer development environments, developers can integrate external applications with SAP systems, exchanging information on the level of business objects. User Interface The SAP systems user interface is designed for ease of use and friendliness by all levels of staff. The SAP graphical user interface, known as SAP GUI, acts as the presentation server and is available in Windows and Macintosh platforms. They all look identical, whatever underlying system they are running on. The SAP GUI includes all graphical capabilities of modern Windows interfaces, with push buttons, menu bars, toolbars, hypertext links, tabs trips, on-focus descriptions, and right-clicking options. The graphical design and functionality is homogeneous across the entire system, which makes training easier and more straightforward for all levels of SAP users. Depending on which SAP application or processing tasks are to be run, screens may be very simple or may contain multiple fields and graphical elements. Customers can also customize and create new menus and screens with the help of the development workbench. Chapter 4 contains all the information needed to learn how to use the system and discusses the available icons, how to move around the system, and some very useful hints. In SAP R/3 releases 4.x and up, the new GUI was designed to be able to show several types of information at the same time. There is also the possibility of transferring the presentation components on demand from SAP to the workstations. This is possible because of the enhancements in the architecture introduced using ActiveX under Windows or JavaBeans. As of the introduction of the ITS, with SAP GUI for HTML, and currently with the possibilities enabled with Web Dynpro, the user interface is slowly switching to a complete Web-based environment, which would ultimately make SAP users able to deploy SAP systems through the SAP Enterprise Portal (the People collaboration layer of SAP Net Weaver). Application Integration The data from the different SAP functional applications are shared and integrated, building what is often known as an internal information highway. This integration can be seen as an implicit applications workflow. One of the main benefits of the set of SAP applications is their capacity for creating a perfect integration between the different business processes of companies. It is that integration between applications that ensures that all business and management information is available to all areas of a company. An accompanying feature that makes application integration stand out is the capacity of doing it in real time. This means that information is constantly updated, so when a manager requests a report about the current balance the system provides instant information about the status of the financial statements. This avoids the difficulty of running end-of-period reports and programs from a traditional legacy system, which has to search and incorporate needed data from other applications before the run. From the point of view of the business processes, the integration of the R/3 application modules used to be represented using the tools available within the R/3 Business Engineer, which is no longer available in latest releases. At the level of data models, this integration can be accessed using the available functions included in the Data Modeler.