Ais a circuit board that contains most of a server.

Ithink it's a) the user may use the song without the permission of the creator but only in certain circumstances

Ireally like network models.

I’d say platform as a service (paas) or application platform as a service (apaas) or platform base service is a category of cloud computing services that provides a platform allowing customers to develop, run, and manage applications without the complexity of building and maintaining the infrastructure typically associated with developing and launching an app.

That is called a  (wimax)           because it  uses wireless transmissions for data communications as much as 35 miles apart.