A table (and along with other supported tables) contains bridge group information. A bridge group is actually a Port-Vlan concept which consists of one or more E-ports and one or more D-ports.

Each D-port includes its associated U-ports and is further subdivided into 3 sub-ports associated with different types of traffic. The CM sub-port carries traffic for the cable-modem itself. The CPEAUTH sub-port carries traffic for an authorized CPE behind a cable-modem. The CPEUNAUTH sub-port carries traffic for an unauthorized CPE behind a cable-modem.

Initially, all ports belong to the OAM&P bridge group when a card is first provisioned. Bridge ports can only exist in one bridge group at a time and can be moved between them.

Generally, the CPEAUTH sub-port on the D card would be in a bridge group with an E port that had access to the internet and the DHCP servers for the ISP used by the subscriber. The CM sub-port would be in a bridge group with an E port that had access to the DHCP servers and administrative controls for the MSO. The CPEUNAUTH sub-port would be in a bridge group that included access to a sign-on server.