Enterprise Administration > Implementing Windchill ESI > Implementing Windchill ESI in an SAP Environment > Understanding Windchill ESI Architecture
  
Understanding Windchill ESI Architecture
This section provides details of Windchill ESI architecture by discussing the following:
Windchill ESI services
Common Business Object (CBO) data model
XML schema specification
Transaction management process
Message logging process
Error handling and notification process
Support for multiple targets
Defaults and cross-referencing support
Getting familiar with these concepts will help you install and configure Windchill ESI more efficiently. The following figure gives an overview of Windchill ESI's modular architecture:
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As for the SOAP Encoding/Decoding block that appears in Windchill, only the Result Response message is SOAP encoded; the block has no relevance to the Response message, since it is plain XML. Conversely, the SOAP decoding occurs in the Windchill ESI Middleware only for the Result Response message and has no relevance to the Response message.