I am not an expert but understand the basics, I am sure others can explain it more.
Basically with card sh....., your receive the signal for the channel you are watching from your satellite dish (this is why your box is connected to a dish) and receive the encryption details from the CS server, via internet ( this is why your box is connected to internet.
What happened is sly has changed the way the encryption system works, so CCCAM can't open them as it used to.
But for IPTV services, what you receive is the video being streamed from the server (this is why you don't need satellite dish connection, only internet). Simple example is like you watching youtube videos. Videos being streamed from Youtube servers. Hope this help