Fault detection method and node device

A fault detection method executed by a first node device, the fault detection method comprising:

• determining whether a second node device detects a possibility of disappearance of a first packet in a network, the first packet being transmitted from a third node device to the second node device;
• and
• when determining that the second node device detects the possibility, transmitting first information to a respective node device on one or more paths present between the first node device and the third node device in the network, the first information requesting to determine whether the respective node device transmits or receives the first packet,
• the determining that the second node device detects the possibility includes:
• when a judgment request related to the first packet is received, identifying a packet address and a first sequence number included in the judgment request,
• determining whether history information in the first node device includes a source of the identified packet address, a destination of the identified packet address, and a second sequence number immediately before the identified first sequence number, and
• when a determination is made that the history information in the first node device includes the source, the destination, and the second sequence number, detecting the possibility of the disappearance of the first packet in the network.

A non-transitory computer-readable medium storing instructions executable by a first node device, the instructions comprising:

• one or more instructions for determining whether a second node device detects a possibility of disappearance of a first packet in a network, the first packet being transmitted from a third node device to the second node device;
• and
• one or more instructions for, when determining that the second node device detects the possibility, transmitting first information to a respective node device on one or more paths present between the first node device and the third node device in the network, the first information requesting to determine whether the respective node device transmits or receives the first packet,
• the determining that the second node device detects the possibility includes:
• when a judgment request related to the first packet is received, identifying a packet address and a first sequence number included in the judgment request,
• determining whether history information in the first node device includes a source of the identified packet address, a destination of the identified packet address, and a second sequence number immediately before the identified first sequence number, and
• when a determination is made that the history information in the first node device includes the source, the destination, and the second sequence number, detecting the possibility of the disappearance of the first packet in the network.