A method for detecting symmetry of optical fibers, comprising: receiving, by a boundary clock, a first timestamp message carrying a first timestamp via a slave port located on a primary path of a optical fiber sending-receiving link, and a second timestamp message carrying a second timestamp via a passive port located on a backup path of the optical fiber sending-receiving link; comparing, by the boundary clock, the first timestamp with the second timestamp, and determining that the primary path and the backup path are not symmetric if a difference value between the first timestamp and the second timestamp is larger than a first preset value, wherein comparing, by the boundary clock, the first timestamp with the second timestamp comprises: calculating, by the boundary clock, a first time offset between the boundary clock and a node sending the first timestamp message according to the first timestamp; calculating, by the boundary clock, a second time offset between the boundary clock and a node sending the second timestamp message according to the second timestamp; and comparing, by the boundary clock, the first time offset with the second time offset, wherein the difference value between the first timestamp and the second timestamp is a difference value between the first time offset with the second time offset, and wherein the first time offset is obtained through transmission of a sync message, a delay request message and a delay response message between the boundary clock and the node sending the first timestamp message, and the second time offset is obtained through transmission of a sync message, a delay request message and a delay response message between the boundary clock and the node sending the second timestamp message. receiving, by a boundary clock, a first timestamp message carrying a first timestamp via a slave port located on a primary path of a optical fiber sending-receiving link, and a second timestamp message carrying a second timestamp via a passive port located on a backup path of the optical fiber sending-receiving link; comparing, by the boundary clock, the first timestamp with the second timestamp, and determining that the primary path and the backup path are not symmetric if a difference value between the first timestamp and the second timestamp is larger than a first preset value, wherein comparing, by the boundary clock, the first timestamp with the second timestamp comprises: calculating, by the boundary clock, a first time offset between the boundary clock and a node sending the first timestamp message according to the first timestamp; calculating, by the boundary clock, a second time offset between the boundary clock and a node sending the second timestamp message according to the second timestamp; and comparing, by the boundary clock, the first time offset with the second time offset, wherein the difference value between the first timestamp and the second timestamp is a difference value between the first time offset with the second time offset, and wherein the first time offset is obtained through transmission of a sync message, a delay request message and a delay response message between the boundary clock and the node sending the first timestamp message, and the second time offset is obtained through transmission of a sync message, a delay request message and a delay response message between the boundary clock and the node sending the second timestamp message. calculating, by the boundary clock, a first time offset between the boundary clock and a node sending the first timestamp message according to the first timestamp; calculating, by the boundary clock, a second time offset between the boundary clock and a node sending the second timestamp message according to the second timestamp; and comparing, by the boundary clock, the first time offset with the second time offset, wherein the difference value between the first timestamp and the second timestamp is a difference value between the first time offset with the second time offset, and wherein the first time offset is obtained through transmission of a sync message, a delay request message and a delay response message between the boundary clock and the node sending the first timestamp message, and the second time offset is obtained through transmission of a sync message, a delay request message and a delay response message between the boundary clock and the node sending the second timestamp message.