Frame transfer route confirmation method, a node, the program and the frame transfer route confirmation system

Frame switching unit 630, a frame analyzer 700, a frame rewrite unit 710, a frame transfer unit 720, a table search unit 730, a forwarding table 740, the MAC learning unit 750, a control frame distributor 760, setting control a vessel 790, upon receipt topology change message, to convert the LT flag from 0 to 1, and clearly indicate that the entry of the pre-switching, the STP controller 780 to leave an entry in the table, before the fault switching LT for execution request, in the entry in the forwarding table 740, and a OAM controller 770 to transfer the LT frame according to the output port of the entry LT flag is 1.