SSIS Architecture

Microsoft SQL Server Integration Services (SSIS) consist of four key parts:

• SSIS Service
• SSIS Object Model
• SSIS runtime engine and the runtime executables
• SSIS dataflow engine 

Integration Services Service:

• Monitors running Integration Services packages and manages the storage of packages
• Integration Services object model
• Includes native and managed application programming interfaces (API) for accessing
• Integration Services tools, command-line utilities, and custom applications

Data Transformation Run-Time Engine:

•      Handles control flow of the package   
•      Support Logging,Debugging ,Config,Connections & transactions.
•      Package,containers,Tasks and Event handles.

Data Flow Engine(ETL):

•    Also called as Data Transformation Pipe Line Engine
•    Data sources or Data Adapters 
•    Transformations 
•    Destination Targets or Destination Adapters 

Please check below SSIS Architecture Diagram