Abstract: A two-way cable network offering high-speed broadband communications delivered via virtual private networks over a multi-channel shared media system. Bi-directional transmission of packet to ATM cell based communications is established between a head end communication controller and a number of subscriber terminal units, whereby individual cells are prioritized and routed according to a virtual connection. Virtual connections are organized to support multiple virtual private networks in a shared media CATV system. The virtual private network to which a particular STU belongs is user selectable and has the flexibility of handling multi up/downstream channels with different MAC domains. The present invention can also handle non-ATM MAC domains via the same common ATM switch. To overcome the limited number of addresses inherent to common ATM switches, a mapping/remapping function is implemented in the port cards. Furthermore, downstream as well as upstream traffic are filtered at each STU.

Abstract: Bi-directional communications system in a CATV network utilizing cell-based Asynchronous Transfer Mode (ATM) transmissions. Packet data existing in any one of several different formats are first converted into ATM cells by a headend controller. Individual cells are then assigned a virtual connection by the headend controller. Based on the virtual connection, the cells can be prioritized and routed to their intended destinations. The cells are transmitted in a shared radio frequency spectrum over a standard cable TV network. A subscriber terminal unit demodulates the received RF signal and processes the cells for use in a computer. Likewise, computers may transmit packet data to their respective subscriber terminal units which are sent to the headend controller over the same CATV network.