Patent ID: 8249448

Claim:
A communication device comprising: a port via which the communication device is operable to communicate with a receiver over a communication channel; command hardware coupled to the port and operable to output a controlled signal over the communication channel to the receiver via the port; monitor hardware operable to monitor the controlled signal as the controlled signal is being output from the command hardware to the receiver via the port and to output a controlling signal to block propagation of the controlled signal before reception of the controlled signal by the receiver is completed if a fault is identified in the controlled signal; and signal blocking circuitry coupled to a transmission path of the controlled signal and to a transmission path of the controlling signal; wherein, when the controlled signal is to be blocked, the signal blocking circuitry applies the controlling signal to the controlled signal such that the receiver at one end of the transmission path of the controlled signal identifies the controlled signal as a faulty signal; and wherein, when the controlled signal is not being blocked, the controlled signal is unimpeded by the signal blocking circuitry.