A typical SAP system consists of various business modules, numerous sector and cross-sector solutions. A distributed system of this nature requires a common infrastructure, which is provided by SAP NetWeaver and in particular, by the SAP Web Application Server (WAS).
Major points to note and keep in mind would be:
• Layers of WAS: presentation, application and database.
• The interfaces used between presentation and application, application and database.
• ICM – Internet Communication Manager
• Roll in / Roll out
• Work processes, Gateway and dispatcher.
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