How is the defaultauthentication module mounted to the system?

I searched for Web. config and machine. config, but did not find the defaultauthentication module. I reflected the code and found that it was originally written in the Code:

?

This module also has an event:

However, the Code writes the ultauthentication module to the dead instance and does not specify what the event will do. Who will specify what the event will do and where?

MATERIALS:

Http://technet.microsoft.com/zh-cn/library/system.web.security.defaultauthenticationmodule.authenticate%28v=vs.110%29

Is specified in global. asax:

You can specify a subroutine named defaultauthentication_onauthenticate in the global. asax file of the application to access the authenticate event of the defaauthauthenticationmodule class.

?

As specified in global. asax, how does one correspond to the instance of this module?

In the initinternal function of httpapplication, you can call hookupeventhandlersforappplicationandmodules to mount it in reflection mode:

?

?

The analysis is complete.

How is the defaultauthentication module mounted to the system?