The Broadband Controller Card is a microprocessor-based system controller and is used to control the overall operation of the BPX switch. The Broadband Controller Card runs the system software for controlling, configuring, diagnosing, and monitoring the BPX switch. Contains the crosspoint switch matrix operating at 800 Mbps per serial link (BCC-32 or BCC-3-32M, or BCC-3-64M) or up to 1600 Mbps (BCC-4V). Contains the arbiter which controls the polling each high-speed data port and grants the access to the switch matrix for each port with data to transfer. Generates Stratum 3 system clocking and can synchronize it to either a selected trunk or an external clock input. Communicates configuration and control information to all other cards in the same node over the backplane communication bus. Communicates with all other nodes in the network. Provides a communications processor for an Ethernet LAN port plus two low-speed data ports.