Patent ID: 8724986

Claim:
A method for transmitting impairment information, comprising: receiving, by a first node on a path, first impairment information from a previous hop node of the first node, wherein the first impairment information comprises a physical impairment parameter of one or more available wavelengths at the previous hop node; updating, by the first node, the first impairment information, wherein physical impairment parameters of all or a part of available wavelengths of the one or more available wavelengths at the previous hop node are updated to physical impairment parameters of the all or a part of available wavelengths at the first node, wherein the physical impairment parameters of the all or a part of available wavelengths of the one or more available wavelengths at the previous hop node are comprised in the first impairment information; judging, by the first node, whether the physical impairment parameters of the all or a part of available wavelengths at the first node exceed a preset range; when the all or a part of available wavelengths comprise a wavelength whose physical impairment parameter at the first node exceeds the preset range, deleting the wavelength whose physical impairment parameter at the first node exceeds the preset range; and when the all or a part of available wavelengths still comprise a residual wavelength after the wavelength whose physical impairment parameter at the first node exceeds the preset range is deleted, sending, by the first node, second impairment information to a next hop node of the first node, wherein the second impairment information comprises a physical impairment parameter of the residual wavelength at the first node.