Disclosed are a
network security protection method, device and
system. Said method includes: when a
signal fault on a link of an optical
transmission network is detected, determining, according to the
signal fault, an optical
transmission network interface where a failure has occurred (101); according to a
service configuration path, transferring said
signal fault to a
packet transmission network interface corresponding to said optical
transmission network interface (102); through said
packet transmission network interface, transmitting a forward fault indication or an
alarm indication signal to the
packet transmission network in order to trigger said packet transmission network to perform an
automatic protection switching (103); and / or, when a failure
signal on a packet service channel of the packet transmission network is detected, determining, according to the failure
signal on said packet service channel, a packet transmission
network interface where a failure has occurred (104); according to the
service configuration path, transferring said failure signal to an optical transmission network interface corresponding to said packet transmission network interface (105); through said optical transmission network interface, transmitting the signal fault to the optical transmission network in order to trigger said optical transmission network to perform a sub-
network connection protection switching (106).