摘要 |
Provided is a node unit which is branch-connected to another communication node via a transport medium, the node unit comprising: a delay measurement unit which transmits a test signal for measuring a delay to an adjacent node unit of the branch-connected upper stage via the transport medium and detects a loopback signal to which the test signal is looped back via the adjacent node unit of the upper stage, thereby measuring an upper stage transmission delay between adjacent nodes of the upper stage; a delay summation unit which, when an adjacent node unit of the branch-connected lower stage exists, receives a lower stage transmission delay transmitted from the adjacent node unit of the lower stage, and sums up the upper stage transmission delay and the lower stage transmission delay; and a control unit which transmits the summed transmission delay to the adjacent node unit of the upper stage. |