PESA’s Switcher Port Expander adds additional branches to the PESA Router Control (PRC) bus from a single system controller. The PRC protocol allows any PESA router with PRC capability to interface with and be controlled by a common system controller, thus becoming an integral component of a larger router system. The Switcher Port Expander greatly enhances this capability by creating two individual 1X4 data switches for PRC bus data, allowing up to eight branches of the PRC bus. The 1RU box is designed to mount near the system controller chassis and isolate cable runs returning to the controller from equipment on the bus. Individual LEDs on the front panel display status for bus transmit and receive connections, as well as error and power-on status.