PURPOSE: To perform efficient packet transmission, by measuring a packet transfer time of a path to be detoured and selecting the optimum detour, when detour control is required.
CONSTITUTION: Assuming that the transmission of information packet is made in a path 18 on a transmission line 10 between a transmission node 1 and an address node 2. If the selection of a detour is required due to a failure of the transmission line 10, the node 1 transmits a packet transfer delay time measuring packet to, e.g., a path 19. The nodes 2 and 3 act like a passing node to the said measuring packet and provide the passing time for the said packet. The measuring packet is returned to the node 1 via transmission lines 6, 8, 9 and 7. The node 1 measures the delay time of the measuring packet, and if the delay time is smaller than the reference value, this path is selected, and if larger, the similar measurement is made to other detours to select the detour.
YOSHIE KINZABUROU
ITSUSHIKI KOUJI
