Abstract: A moving target defense scheme for a serial communications system is disclosed herein. A bus controller generates and broadcasts a nonce to remote terminals over a bus. The bus controller and the remote terminals generate a randomized sequence based upon the nonce and a shared secret that is shared between the bus controller and the remote terminals. The bus controller broadcasts first messages over the bus on first addresses that are derived from first portions of the randomized sequence. The remote terminals listen for the first messages that are broadcast over the bus on the first addresses. The bus controller broadcasts a shift message that causes the remote terminals to listen for second messages that are broadcast over the bus on second addresses that are derived from second portions of the randomized sequence.