Patent ID: 7539128

Claim:
A method for protecting and restoring a link, comprising: transmitting/receiving a liveness-confirming message for confirming the liveness of the link between an up-node and a down-node respectively connected to both ends of the link at a predetermined message transmission period, to judge whether a fault is generated on the link; allowing the up-node and down-node to update link information, respectively when it is judged that the link fault is not generated; and restoring the link having the fault using predetermined restoration channel information based on an offered load measured when the link is in a normal state when it is judged that the link fault is generated; the up-node merging a large number of data bursts in a transmission wavelength into a small number of protection wavelengths using the restoration channel information and transmitting the protection wavelengths; and the down-node restoring the merged wavelengths to the transmission wavelength through wavelength conversion using the restoration channel information.