FSHost for a "regular" session?

Hi everyone!
I wanted to know, can players only join my FSHost session via FSClient?
If i remember right, i saw minimum 2 sessions (in the Gamespy client)
Where the host used FSHost (With commands and so on) and they could ban players. Is it another software? Where can i get it? Is it free?
If not another software, how do i get my FSHost session into Gamespy?
Thank you very much!