Abstract:There are two kinds of massage signal of intelligent substation, process layer massage and control layer massage. Information security to follow the “safe partition, network, horizontal isolation, longitudinal certification” principle, through encryption, digital signatures, the virtual network, such as firewall and intrusion detection technology, rely on the active defense with passive defense, build up two lines of defense of the information security protection, enhance the information availability, confidentiality, integrity, and nonrepudiation.