Firewall switch. Options: 1. enable(1) -indicates that when the device needs to control the protocol used to access the device, this command can be executed to enable(1) the firewall switch of the protocol. After the firewall switch of the protocol is enabled(1), the device can control the operator who accesses the device with the protocol and reject the access of the operator whose IP address is not in the permitted address segment. 2. disable(2)-indicates that if the operator is already online, the device forces the operator to go offline. The firewall switch can be disabled when the firewall switch mode is set to disable(2). After the firewall switch is disabled(2), the device does not control the operator who accesses the device with the protocol. By default, the firewall in the system is in the disabled state.