Delay measurement system and delay measurement method, as well as delay measurement device and delay measurement program

A delay measurement system that measures a delay time on a network including a transmission source node, a transmission destination node connected to the transmission source node through relay nodes, and the relay nodes that relay communication from the transmission source node to the transmission destination node, comprising:

• the transmission source node comprising:
• a source clock generation section that generates a clock;
• a control packet generation section that generates a delay measurement packet at a regular interval based on the clock generated by the source clock generation section;
• and
• a control packet transmission section that transmits the generated delay measurement packet to the transmission destination node,
• the relay nodes each comprising:
• a control packet analysis section that selects the delay measurement packet from a reception frame;
• a delay calculation section that calculates a delay time of the delay measurement packet transmitted from the transmission source node to its host node in the network;
• a control packet correction section that stores the calculated delay time and a node identifier of its host node in the delay measurement packet to correct the delay measurement packet;
• and
• a control packet transmission section that transmits the delay measurement packet corrected by the correction section toward the transmission destination node,
• the transmission destination node including:
• a control packet analysis section that selects the delay measurement packet from a reception frame;
• and
• a delay measurement section that measures a delay of the delay measurement packet transmitted from the transmission source node to its host node in the network,
• the transmission destination node calculating, based on the delay time and node identifier stored in the delay measurement packet, any one or a combination of the delay time between the transmission source node and transmission destination node, delay time between the transmission source node and relay node, delay time between the relay nodes, and delay time between the relay node and transmission destination node.

A delay measurement device that serves as a transmission destination node connected to a transmission source node over a network including a relay node and measures a delay time between the transmission source node and the transmission destination node, comprising:

• an interface that receives a delay measurement packet generated at a regular interval based on a source clock generated by the transmission source node;
• a control packet analysis section that selects the delay measurement packet from a reception frame;
• and
• a delay measurement section that measures a delay of the delay measurement packet transmitted over the network from the transmission source node to its host node.

A delay measurement method that a system including a transmission source node and a transmission destination node connected to the transmission source node over a network including a relay node performs to measure a delay time in a direction from the transmission source node to the transmission destination node, comprising steps of:

• generating a clock by the transmission source node;
• generating a delay measurement packet at a regular interval by the transmission source node based on the generated clock;
• transmitting the generated delay measurement packet to the transmission destination node by the transmission source node;
• selecting the delay measurement packet from a reception frame by the transmission destination node;
• and
• measuring, by the transmission destination node, a delay of the delay measurement packet transmitted from the transmission source node to its host node in the network.

A delay measurement method performed by a system including a network including a transmission source node, a transmission destination node connected to the transmission source node through relay nodes, and the relay nodes that relay communication from the transmission source node to the transmission destination node, comprising steps of:

• generating a clock by the transmission source node;
• generating a delay measurement packet by the transmission source node at a regular interval based on the generated clock;
• transmitting the generated delay measurement packet to the transmission destination node by the transmission source node;
• selecting the delay measurement packet from a reception frame by each of the relay nodes;
• calculating a delay time of the delay measurement packet transmitted from the transmission source node to its host node in the network by each of the relay nodes;
• storing the calculated delay time and a node identifier of its host node in the delay measurement packet to correct the delay measurement packet by each of the relay nodes;
• transmitting the corrected delay measurement packet toward the transmission destination node by each of the relay nodes;
• selecting the delay measurement packet from a reception frame by the transmission destination node;
• measuring, by the transmission destination node, a delay of the delay measurement packet transmitted from the transmission source node to its host node in the network;
• and
• calculating, based on the delay time and node identifier stored in the delay measurement packet, any one or a combination of the delay time between the transmission source node and transmission destination node, delay time between the transmission source node and relay node, delay time between the relay nodes, and delay time between the relay node and transmission destination node by the transmission destination node.

A non-transitory computer-readable recording medium that stores a delay measurement program that is installed in a transmission destination node connected to a transmission source node over a network including a relay node and measures a delay time between the transmission source node and the transmission destination node, allowing a computer to function as:

• an interface that receives a delay measurement packet generated at a regular interval based on a source clock generated by the transmission source node;
• a control packet analysis section that selects the delay measurement packet from a reception frame;
• and
• a delay measurement section that measures a delay of the delay measurement packet transmitted over the network from the transmission source node to its host node.