modules in authorize{} and authenticate{} sections

[bastardinho69]

Hi, guys,

I have successfully set up FreeRADIUS server to use Active Directory to 
authenticate LAN users.
My authorize{} and authenticate{} section configuration in radiusd.conf 
file looks like this:

authorize {
        preprocess
        eap
        mschap
    }
authenticate {
        Auth-Type MS-CHAP {
        mschap
        }
    eap
    }

As u see, in both sections there is modules eap and mschap mentioned. 
Can anybody tell me why it is so? Or where to look for the answer? I 
have been checking the logs from running radius in debug mode but i 
cannot find the definite answer, for example, in conversation between 
radius server and supplicant, mschap in authorize section always returns 
noop, so my question is- why it is needed there if it always returns noop?

Thank you.