A cordless telephone base unit includes first and second network controllers and a terminal controller. The first network controller establishes concurrent call sessions for a single voice call account with a service provider over the Internet. Each of the concurrent call sessions includes at least one media session. Each of the media sessions has a corresponding software port number. The second network controller wirelessly communicates with cordless telephones, which each have a corresponding IP address. The terminal controller connects each of the media sessions to one or more of the cordless telephones and includes a switch logic that implements a terminal map, and a switch fabric that connects the cordless telephones with the media sessions according to the terminal map. The terminal map associates the corresponding IP address of each of the cordless telephones with the corresponding software port numbers of one or more of the media sessions.