Overview of SQL Server Reporting Services 2012 Architecture, Features, and Tools - Learning SQL Server Reporting Services 2012 - page 126

In order to create Power View reports, the new feature in SSRS 2012, you start off
creating a data source in SharePoint library. Because of the RS Service, you can
enable Reporting Services features such as Report Builder; and associate BISM
file extensions to support connecting to tabular models created in SSDT deployed
to Analysis Services Server. When Reporting Services is installed in SharePoint
Integrated mode, SharePoint Web parts will be available to users that allow them
to connect to RS Native mode servers to work with reports on the servers from
within SharePoint Site.

Native mode
The following schematic taken from Microsoft documentation ( http://msdn.
microsoft.com/en-us/library/ms157231.aspx ) shows the major components
of a Native mode installation:

Reporting
Services
Configuration

Web
browser

Report
Builder

Report
Designer

Third-party
tools

Report
Manager

Report server components

Authentication
extensions Programmatic

interfaces

Scheduling and
Delivery Processor

Report processing
extensions

Report
Processor

Rendering
extensions

Delivery
extensions

Data processing
extensions

Report server database

Data source

Key

Windows services components
Web service components
Report Manager component
Components common to Windows service and Web service