Message output from line interface module is buffered. Then, output control unit reads out buffered message. Header of message written to a header inspection unit generates unicast and multicast table look up key words to carry out unicast and multicast table look up. Header of message is written into buffered first-in, first-out register of processing header of message. Using result of unicast table look up, result of multicast table look up and the message, the multicast RPF inspection unit obtains RPF inspection result. Synthesizing inspection result of message header, result of unicast, result of multicast RPF, and logic arbitration unit generates inner reporting message header or inner forwarding message header. Repackaging the message by using the inner message header, the inner message generation unit sends generated message to be reported to main control module, and sends generated forwarding message to exchange network. The invention also discloses IPv6 router for the method.