| 摘要 |
PROBLEM TO BE SOLVED: To prevent a loop fault by detecting the loop fault almost without imposing a load on the cable modem. SOLUTION: The cable modem terminator 2 connecting to a user side cable mode via a host network and a CATV cable 3 is provided with a frame transmission means 16 that sends a check frame having transmission source information and transmission direction information denoting to which of a host network side or a CATV cable side a frame is sent and also with fault discrimination means (17, 18) that detect a loop fault based on reception direction information denoting to which of the host network side or the CATV cable 3 the check frame is received and on each information in the check frame upon the receipt of the check frame. |
