Abstract: A protocol converter converts from a first data and command exchange protocol to a second, different data and command exchange protocol. The protocol converter includes a first interface for sending and receiving data and commands in a first protocol, such as DSCH, and a second interface for sending and receiving data and commands in a second, different protocol, such as Ethernet. The device can receive data and commands simultaneously at either interface and convert from the first protocol to the second protocol or from the second protocol to the first protocol without loss of integrity to the flow of the data and commands. Additionally, the device provides a redundant connection, a safeguard in the event of primary path failure.

Abstract: A modular switch box which is responsive to a control signal, is diagnosable, and is not dependent upon the type of protocol being switched. There may be a plurality of switch boxes wherein each switch box includes a plurality of inputs and an output. There is a selector for selecting which input is connected to the output and a controller for controlling the selector. There is also a control means for controlling the switch boxes. The switch boxes are connected in a chain so that the input of one switch box is connected to the output of the next, etc., until the output of the last switch box is connected back to the controller. The controller sends a command message to the first switch box which then executes the command and forwards the message on to the next switch box, etc., until the command returns to the controller. In this manner, the controller knows that all switch boxes have received the command.