A remote digital firing system includes a firing circuit operative to fire
remote mission payloads, a firing control panel linked to the firing
circuit, and a digital code plug configured to communicate with the
firing circuit and firing control panel. The firing circuit can generate,
write and store one-time random session variables to the digital code
plug. The firing circuit validates digital messages received from the
firing control panel by comparing one-time random session variables
embodied in the messages with the stored one-time random session
variables, before firing the payload.