A security controller (SC) restoration method is provided. The method includes: designating, by a master node, a node to which a backup SC belongs, where the master node includes an original DM or a backup DM; sending, by the master node to a first node, a message indicating the backup SC, where the message indicating the backup SC includes an identifier of the node to which the backup SC belongs; in a case in which a node to which an original SC belongs is disconnected, sending, by the master node to the first node, a message for enabling an SC function, for performing authentication, according to the message for enabling an SC function.