Abstract: A redundant repeater connected between two transmission mediums that can operate in a repeat state where packets are repeated between the mediums, and a standby state where no packets are repeated and where the repeater determines whether packets are being properly repeated between the transmission mediums by another device. If the repeater determines that packets are being independently repeated it remains in the standby state, and will attempt to leave the standby state and return to the repeat state only if it determines that packets on one medium are not being repeated to the second medium. Two repeaters can be redundantly connected across the same transmission mediums with one operating in repeat state and the other in standby. If one repeater fails, the other will begin repeating all received packets. The repeater determines whether packets are being properly repeated by detecting overlapping or non-overlapping packets between its two transmission mediums.