A routing node, wherein the routing node comprises: at least one optical buffer, a switching node, and at least one transmission waveguide, wherein a quantity of optical buffers is the same as a quantity of transmission waveguides; an output end of each optical buffer of the at least one optical buffer is connected to an input end of the switching node, and each transmission waveguide of the at least one transmission waveguide is connected to an output end of the switching node; the optical buffer (201 is adapted to receive an optical signal, and parse the optical signal, to obtain an identifier of a destination routing node; and send the identifier of the destination routing node to the switching node; and the switching node adapted to determine, according to the identifier of the destination routing node, whether an output port required by the destination routing node is currently in an idle state or a busy state; and if the output port is in a busy state, the switching node is adapted to control the optical buffer to store the optical signal by sending a storage instruction to the optical buffer, and until the output port required by the destination routing node changes to be in an idle state, the switching node is adapted to send a transmission instruction to the optical buffer, then is adapted to send the optical signal that is stored in and sent by the optical buffer to the destination routing node by using a transmission waveguide corresponding to the output port required by the destination routing node; and if the output port is in an idle state, the switching node is adapted to send a transmission instruction to the optical buffer, then is adapted to send the optical signal that is received and sent by the optical buffer to the destination routing node by using a transmission waveguide corresponding to the output port required by the destination routing node. at least one optical buffer, a switching node, and at least one transmission waveguide, wherein a quantity of optical buffers is the same as a quantity of transmission waveguides; an output end of each optical buffer of the at least one optical buffer is connected to an input end of the switching node, and each transmission waveguide of the at least one transmission waveguide is connected to an output end of the switching node; the optical buffer (201 is adapted to receive an optical signal, and parse the optical signal, to obtain an identifier of a destination routing node; and send the identifier of the destination routing node to the switching node; and the switching node adapted to determine, according to the identifier of the destination routing node, whether an output port required by the destination routing node is currently in an idle state or a busy state; and if the output port is in a busy state, the switching node is adapted to control the optical buffer to store the optical signal by sending a storage instruction to the optical buffer, and until the output port required by the destination routing node changes to be in an idle state, the switching node is adapted to send a transmission instruction to the optical buffer, then is adapted to send the optical signal that is stored in and sent by the optical buffer to the destination routing node by using a transmission waveguide corresponding to the output port required by the destination routing node; and if the output port is in an idle state, the switching node is adapted to send a transmission instruction to the optical buffer, then is adapted to send the optical signal that is received and sent by the optical buffer to the destination routing node by using a transmission waveguide corresponding to the output port required by the destination routing node.