A、The information system under the network environment is more complex than the stand-alone system, and the information security problem is more difficult to be guaranteed than the stand-alone system.
B、E-mail is a means of communication between individuals. It is private and does not use floppy disks. It will not infect computer viruses.
C、Firewall is one of the effective measures to protect internal network from external attacks.
D、The core of network security is the security of the operating system, which involves the protection of information in the state of storage and processing.
喵查答案:E-mail is a means of communication between individuals. It is private and does not use floppy disks. It will not infect computer viruses.