Understanding the importance of Exchange Infrastructure

By Shiva

XI is an Integration technology and Platform

• For integrating SAP systems with Non SAP systems
• For integrating A2A and B2B applications
• For synchronous and asynchronous exchange of messages
• For cross component Business Process Management

To understand XI let us see the following topics 

Need for Middleware 

Common definition is that middleware is the "glue" between software components or between software and the network or it is the slash in Client/Server.  

•         This is about those forms of middleware that are used to connect applications to other applications. We generally refer to the use of this type of middleware as Enterprise Application Integration or EAI.  EAI middleware mediates between applications in a number of ways, but most commonly we think in terms of the transformation and routing of data and the orchestration of business process flows.

•         There is the implication here that these applications reside in a heterogeneous world--different operating platforms, disparate data models and data stores, and heterogeneous network and communications protocols.  

Overview of XI 

Success of XI over Other Commercial EAI tools: 

•         Reduced maintenance costs: As the client replaced multiple integration technologies with SAP XI, it gained immediate cost savings by reducing associated maintenance costs. Additionally, the client gained the capability to utilize its manpower more effectively. 

•         Enhanced message monitoring functionality: As SAP XI provides auto handling of persistence of messages, it has enabled the client to monitor and restart failed messages. This has also eliminated the possibility of redundant/duplicate data into the system along with related efforts to identify the same. As all messaging is routed through one system, the client needs to monitor only SAP XI instead of having to monitor four systems: (Web Application system, XML parser application, VB based application) in the existing set up 

•         Enhanced flexibility: The ability to modify applications and add new functionalities without impacting other systems and businesses gave the client tremendous flexibility in reacting to dynamic changes in the market.

•         Standardizes on the technology integration layer that would be used for connectivity between all systems

•         Eliminate the need for “point-to-point” connectivity between systems

•         Achieve a central monitoring of message flow, instead of having to monitor several systems 

Enterprise IT motto 

•         Yesterday

Most conventional or traditional enterprise applications were custom built to address a specific business need.

•         Today

The present advanced enterprise application’s addresses multiple business tasks, with each landscape having a higher degree of heterogeneous complexity. 

•         Difference in picture : Middleware/EAI 

Integration solutions enable many applications/companies to create a ‘single view’ of all their enterprise data and an infrastructure ensuring that applications can exchange and update business central data, no matter where it resides. 

Evolution of SAP 

 At first a single database integration in a single centralized data model: In one system with several applications one database, (e.g. an R/3 system with MM, SD, CO, FI, HR, …) with the applications having access to the data structures across the components. Integration in this case is and was fairly easy. 

Then SAP and 3^rd party vendors provided other solutions as e.g. CRM. SRM,.. These solutions and their respective systems needed to be integrated to the ERP environment (e.g. an R/3 backend system). This brought added complexity and the beginning of many individual point-to-point connections. 

With the SAP Exchange Infrastructure and collaborative business, SAP approaches the integration challenge from a different angle. The basic idea is to provided a runtime infrastructure which allows heterogeneous systems to be tied together with fewer connections and at the same time, in order to connect those applications and let message flow from one application to the other, have a centralized storage of the integration knowledge. 

Business drivers of Integration Projects:

•  New Systems haven’t replaced the existing legacy systems 

• Necessity to consolidate and globalize the business 

• Search for increased productivity 

• Raised expectations from Web applications/experiences

Types of Integration Solutions:

•         Data Coordination

      Mainly deals with transactional data between applications. 

•         Business Process Management/Orchestration

      Mainly focuses on modeling and orchestrating the workflow between individual functions and applications. 

•         Business Activity Monitoring

      Goal is to provide management with immediate awareness of changing business events across the enterprise.     

•         Composite Application Development

      Combines the data and functionality of an enterprise’s existing ones with new business process logic, custom code and user -facing front ends. 

Middleware flow:

Component view of XI

XI is not a single component, but rather a collection of components that work together flexibly to implement integration scenarios.

Integration Builder: A client-server framework for accessing and editing two stores of Shared Collaboration knowledge. It has two parts, which are fat clients to SLD where we can import the objects and use them locally. The basic reason for separating Integration Repository from Integration Directory is because by separating design time activities from configuration time activities, SAP can ship content from the Integration Repository, which each customer can implement for their specific landscape in the Integration Directory.  

Integration Repository: It is used for the design and development of interface, Process and Mapping objects that are used to implement Integration Scenarios. Usually they contain static objects, which can be used for different landscapes by defining the routing rules in Integration Directory. 

Integration Directory: They contain dynamic objects where in we configure scenarios using the objects from Integration Repository and route the messages between systems. 

Integration Server: This component provides run time for XI. This is central processing engine of XI.  

Business Process Engine: Business Process Engine enables SAP Netweaver with BPM capability by processing integration processes at runtime. BPE uses functions of the workflow engine and generates workflow from integration process at runtime.  

Integration Engine: Integration engine enables processing of XML messages that are exchanged between applications in heterogeneous system landscapes. Using adapters such as IDoc, http, it can process IDocs(Intermediate documents), http requests and Remote Function Calls. It is runtime environment of SAP Exchange Infrastructure, which has the task of receiving, processing and forwarding XML messages. Processing is done with the evaluation of Collaboration agreements, by determination of receivers and execution of mapping programs.  

Adapter Engine: Adapter engine is used to connect Integration Engine to SAP systems and external systems. Various types of adapters are provided to convert XML and HTTP based messages to the specific message protocol and format required by the partner systems and vice-versa. It is based on adapter framework, in turn based on SAP J2EE Engine (as part of the SAP Web Application Server) and J2EE Connector Architecture (JCA).