Internet radio

I have a radio station client who would like to have their station to be heard over the internet. Does anybody knows how is that done? I dont need specific info right now, just a basic procedure so I can explain how its done. They’re more likely to put the idea on hold due to budget, but I’d like to give an explanation of the procedures and stuff?

You will need a live connection of some type connected to a computer which will then change it to asx format and send it through the net as far as I know