How does it work on the carrier side?

Hi, first time here!

How does a carrier work with RIM in order to provide the Blackberry service to the end user?


They have to somehow register the device PIN and IMEI together with RIM right?

I would like to know some more technical aspects of how the service works, especially the BIS, i would like to have it but my carrier here in Brasil is a little lost (as usual) they are giving me wrong information and pointing me on the wrong direction.

Thanks

BTW, sorry if i posted in the wrong categoy, feel free to change if needed :D