JP7694826B2 - Management device, management method, and management program - Google Patents

Description

The present invention relates to a management device, a management method and a management program.

Methods for measuring network (NW) information include, for example, xflow, which monitors ports, and probe packet monitoring as defined in RFC5357.

xflow collects information based on 5 tuples per packet, but since there is no identifier to identify the logical surface, it was not possible to collect network information on a slice basis.

In contrast, probe packet monitoring makes it possible to measure logical transfer delays using SR (Segment Routing) probe packets. This method measures the network quality within an SR network by measuring the delay time within the SR network.

In addition, a method has been proposed for measuring network quality from a NE (Network Element) to a server, in which quality is measured using probe packets such as HTTP.

JP 2014-160900 A

As a network engineer, “NetFlow”, [online], [searched May 10, 2022], Internet <URL: https://www.infraexpert.com/study/netflow1.html> RFC5357 “A Two-Way Active Measurement Protocol (TWAMP)”. “Configuring Cisco IOS IP SLA Operations,” Cisco, Dec.18, 2012., [online], [Retrieved May 10, 2022], Internet <URL: https://www.cisco.com/cisco/web/support/JP/docs/SW/LANSWT-Access/CAT2960SWT/CG/012/swipsla.html?bid=0900e4b182e246ec> Cisco, “Segment Routing Tutorial (Monitoring a remote peering link),” JANOG40 Meeting in Fukushima, July 18, 2017, [online], [Retrieved May 10, 2022], Internet <URL: https://www.janog.gr.jp/meeting/janog40/application/files/2415/0051/7614/janog40-sr-kamata-takeda-00.pdf>

Conventional methods were unable to measure end-to-end network quality for each slice, and because there are a large number of servers on the network, measuring the network quality to all servers had the problem of consuming a large amount of resources.

The present invention has been made in consideration of the above, and aims to provide a management device, management method, and management program that can measure end-to-end network quality for each slice while reducing network resource consumption due to quality measurement.

In order to solve the above-mentioned problems and achieve the object, the management device of the present invention is a management device that calculates an end-to-end forwarding delay time, which is a forwarding delay time within a network from a network edge node to which a UE (User Equipment) is connected and a forwarding delay time from the network edge node to a cloud server, and is characterized in having a first acquisition unit that acquires a first forwarding delay time, which is a forwarding delay time from the network edge node to the representative cloud server, for each area in advance based on communication information of a probe packet transmitted from the network edge node to a representative cloud server of each area, a second acquisition unit that performs an intra-network probe and acquires a second forwarding delay time, which is a forwarding delay time within the network, for each slice, and a calculation unit that sums up a value based on the first forwarding delay time of the area corresponding to the end-end to be calculated among the first forwarding delay times acquired by the first acquisition unit and a second forwarding delay time of the slice corresponding to the end-end to be calculated among the second forwarding delay times acquired by the second acquisition unit, and sets the summed time as the end-to-end forwarding delay time.

According to the present invention, it is possible to measure end-to-end network quality for each slice while reducing network resource consumption due to quality measurement.

FIG. 1 is a diagram for explaining an overview of a network quality measurement process according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of a configuration of a communication system according to an embodiment. FIG. 3 is a diagram for explaining measurement of the first transfer delay time. FIG. 4 is a diagram showing an example of the first transfer delay measurement result. FIG. 5 is a diagram showing an example of a measurement result of the second transfer delay time. FIG. 6 is a diagram for explaining calculation of end-to-end transfer delay time. FIG. 7 is a flowchart showing the procedure of the Flow information management process. FIG. 8 is a flowchart showing a processing procedure of the first transfer delay time measurement processing. FIG. 9 is a flowchart showing the procedure of the second transfer delay time measurement process. FIG. 10 is a flowchart showing the procedure of the end-to-end delay calculation process. FIG. 11 is a diagram for explaining an existing method for monitoring a network in the prior art. FIG. 12 is a diagram for explaining an existing method for monitoring a network in the prior art. FIG. 13 is a diagram illustrating an example of a computer that realizes the management device by executing a program.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to this embodiment. In addition, in the description of the drawings, the same parts are indicated by the same reference numerals.

[Embodiment]
First, a communication system according to an embodiment will be described with reference to Fig. 1. Fig. 1 is a diagram for explaining an overview of a network quality measurement process according to an embodiment.

In the embodiment, the network (NW) quality is measured by measuring the transfer delay time (end-to-end transfer delay time) from the NW edge node to which the UE (User Equipment) is connected to the cloud server for each slice. Note that the SID in FIG. 1 stands for Segment Identifier. The node has a logical path monitoring function and a physical path monitoring function for each slice.

In the communication system of the embodiment, a probe packet is sent from a network edge node (e.g., node N15) to a representative cloud server (router, SW, server) of each area, and the forwarding delay time (first forwarding delay time) from the network edge node to the representative cloud server for each area is measured in advance. In the communication system, the first forwarding delay time from the network edge node to the representative cloud server for each area is obtained in advance by a probe for the cloud server ((1) in FIG. 1).

In a communication system, a probe packet is used to measure the network (e.g., in an SR network) to obtain the forwarding delay time (second forwarding delay time) in the network for each slice in advance ((2) in FIG. 1). For example, in a communication system, a probe packet is sent from a node at the edge of the network (e.g., node N15) to another node at the edge of the network (e.g., node N1) to obtain the second forwarding delay time for each slice ((2) in FIG. 1).

Then, the communication system adds together the first transfer delay time acquired by the intra-network probe and the second transfer delay time acquired by the server-directed probe, corresponding to the slice and area for which quality is to be measured. In this way, the communication system acquires the end-to-end transfer delay time corresponding to the slice and area for which quality is to be measured ((3) in FIG. 1).

In this way, in the embodiment, measurement of end-to-end network quality passing through the slice to be measured in the network and the network edge and server is realized. Furthermore, in the communication system, it is only necessary to measure the transfer delay time to the representative cloud server for each area, so it is possible to reduce network resource consumption due to quality measurement compared to a method of measuring network quality to all servers.

[Communication system]
Next, a configuration of a communication system according to an embodiment will be described below. Fig. 2 is a diagram showing an example of a configuration of a communication system according to an embodiment.

As shown in FIG. 2, the communication system 100 has a configuration in which a UE 20 and a cloud server 40 (router, SW, server) are connected via a NW 30. There are multiple UEs 20 and cloud servers 40. The communication system 100 has a management device 10 that measures the end-to-end transfer delay time for each slice.

[Management device]
The management device 10 will be described. The management device 10 is realized by, for example, loading a predetermined program into a computer or the like including a ROM (Read Only Memory), a RAM (Random Access Memory), a CPU (Central Processing Unit), etc., and having the CPU execute the predetermined program. The management device 10 also has a communication interface for transmitting and receiving various information to and from other devices connected via a network, etc.

As shown in FIG. 1, the management device 10 has a network topology management unit 11, an area-unit cloud server management unit 12, a flow information acquisition unit 13, a flow information management unit 14, a server measurement unit 15, a cloud server delay time measurement unit 16, a network measurement unit 17 and an end-end delay calculation unit 18.

The network topology management unit 11 acquires topology information, which is the configuration information of the network, and manages the configuration of the NW30 based on the topology information. The network topology management unit 11 manages the routes of slices based on the topology management.

The area-based cloud server management unit 12 has management information for the cloud servers installed in each area and manages various information for the cloud servers on an area-by-area basis.

The flow information acquisition unit 13 acquires flow information of NW30.

The Flow information management unit 14 manages the Flow information acquired by the Flow information acquisition unit 13. For example, the Flow information management unit 14 acquires dst information on the Flow based on the Flow information acquired by the Flow information acquisition unit 13. Then, the Flow information management unit 14 derives the area corresponding to the destination from the dst information.

For server-directed probes, the server measurement unit 15 transmits probe packets from the edge nodes of the NW 30 to the cloud servers 40 representing each area.

The cloud server delay time measurement unit 16 measures in advance for each area a first delay time, which is a transfer delay time from the NW30 edge node to the representative cloud server, based on communication information of a probe packet transmitted from the NW30 edge node to the representative cloud server 40 of each area. The cloud server delay time measurement unit 16 registers or updates the first transfer delay time obtained by measuring for each area.

Figure 3 is a diagram explaining the measurement of the first forwarding delay time. In the server-directed probe, the management device 10 searches for an area corresponding to the destination of the packet from the dst information of the packet destined for the cloud server 40. Then, the cloud server delay time measurement unit 16 measures the forwarding delay time to the cloud server 40 for each area ((1) in Figure 3).

The cloud server delay time measurement unit 16 causes the server measurement unit 15 to transmit a probe packet from the edge node of the network 30 to the cloud server 40 representing each area, and measures the first forwarding delay time for each area. The cloud server delay time measurement unit 16 measures, as the first forwarding delay time, the forwarding delay time between the network edge and any of the routers, switches, or servers of the cloud server established for each area.

Here, based on the concept of distance, it can be said that the difference in forwarding delay time between cloud servers is within the error range if they are in the same area. Based on this, in the embodiment, the forwarding delay time from the edge node of NW30 to the representative cloud server 40 is set to the forwarding delay time from the edge node of NW30 to each router, SW, and server in the same area as the representative cloud server 40.

Therefore, in the embodiment, since the forwarding delay time is not measured for all routers, switches, and servers within the area, it is possible to reduce network resource consumption due to quality measurement compared to when the forwarding delay time is measured for all routers, switches, and servers within the area.

Figure 4 is a diagram showing an example of the first forwarding delay measurement result. Figure 4 shows the results of measuring the forwarding delay time between the NW and cloud server of each server at the NW edge node for each slice. Figure 4 shows, for example, the results of measuring the forwarding delay time between the NW edge and cloud server of servers 1 and 2 in the American area at node N15 for each slice 1 and 2.

The cloud server delay time measurement unit 16 measures the transfer delay time between node N15 and servers 1 and 2 multiple times for each slice 1 and 2. Based on these measurement results, the cloud server delay time measurement unit 16 calculates the average and deviation of the transfer delay time between node N15 and servers 1 and 2, and registers the calculated average and deviation as information related to the transfer delay time between node N15 and servers 1 and 2 (for example, frame W41).

At this time, the cloud server delay time measurement unit 16 may calculate the average and deviation of the transfer delay time by dividing it into a specified time period (daytime or nighttime) or a specified period (day of the week, end of the month, etc.) depending on the usage status of the service to be measured.

The network measurement unit 17 measures the second forwarding delay time in advance for each slice by performing intra-network probing. The network measurement unit 17 determines the slice through which the probe packet passes based on the tunnel ID of the probe packet, etc.

Figure 5 shows an example of the measurement result of the second forwarding delay time. The network measurement unit 17 measures the forwarding delay time of each slice at each node in the network 30 in advance. The network measurement unit 17 registers or updates the measured forwarding delay time for each slice. Box W51 in Figure 5 shows the measurement result of the forwarding delay time of slice 1 at node N15.

The end-end delay calculation unit 18 calculates the end-to-end transfer delay time to be calculated by adding up a value based on the first transfer delay time of the area corresponding to the end-to-end for which the transfer delay time is to be calculated and a second transfer delay time corresponding to the slice corresponding to the end-to-end for which the transfer delay time is to be calculated.

Figure 6 is a diagram explaining the calculation of the end-to-end transfer delay time. The end-to-end delay calculation unit 18 refers to the destination dst address from the flow information of the packet communication acquired by the flow information management unit 14, and searches for which area the packet is destined for ((1) in Figure 6). The end-to-end delay calculation unit 18 refers to the first transfer delay time measurement results for each area (e.g., the measurement results in Figure 4), and acquires the first transfer delay time for the corresponding area ((2) in Figure 6).

The end-end delay calculation unit 18 determines the slice for which the transfer delay time is to be calculated based on segment routing and tunnel protocols. The end-end delay calculation unit 18 refers to the second delay time measurement results of each slice (e.g., the measurement results in FIG. 5) and obtains the transfer delay time of the slice for which the calculation is to be performed. At this time, the end-end delay calculation unit 18 obtains and adds up the transfer delay times of all nodes through which the slice for which the calculation is to be performed passes.

The end-to-end delay calculation unit 18 calculates the end-to-end transfer delay time to be calculated using equation (1).

The network-server delay measurement in formula (1) is a value based on the first transfer delay time of the area corresponding to the end-end for which the transfer delay time is to be calculated. The NW delay measurement is the second transfer delay time corresponding to the slice corresponding to the end-end for which the transfer delay time is to be calculated.

At this time, the end-end delay calculation unit 18 applies either the average value of the first transfer delay time or the maximum value of the first transfer delay time calculated based on the average value and deviation of the first transfer delay time, depending on the quality requirements of the slice corresponding to the end-end for which the transfer delay time is to be calculated, as a value based on the first transfer delay time in equation (1).

For example, for a service that is not strict about transfer delay, the end-end delay calculation unit 18 adopts the average value of the first transfer delay time. Also, for a service that is strict about transfer delay, the end-end delay calculation unit 18 adopts the maximum value of the first transfer delay time. For example, the strictness of the transfer delay for each service is set in five stages, with stage 5 being strict about the transfer delay, stages 3 and 4 being standard strictness about the transfer delay, and stages 1 and 2 being set as not strict about the transfer delay.

In this way, the management device 10 uses the transfer delay time to the cloud server on an area basis to calculate the end-to-end transfer delay time for all of the hundreds to thousands of servers without measuring the transfer delay time.

[Flow information management processing]
Next, a description will be given of the Flow information management process performed by the management device 10. Fig. 7 is a flowchart showing the processing procedure of the Flow information management process.

The Flow information acquisition unit 13 acquires Flow information of the NW 30 (step S1). The Flow information management unit 1414 acquires dst information on the Flow based on the Flow information acquired by the Flow information acquisition unit 13 (step S2). Then, the Flow information management unit 1414 derives the corresponding area of the destination from the dst information (step S3).

[First transfer delay time measurement process]
Next, a description will be given of the second transfer delay time measurement process performed by the management device 10. Fig. 8 is a flowchart showing the processing procedure of the second transfer delay time measurement process.

The server measurement unit 15 transmits a probe packet from the edge node of the network 30 to a representative cloud server 40 (router, switch, server) for each area. The cloud server delay time measurement unit 16 measures the first forwarding delay time between the edge node of the network 30 and the cloud server 40 for each area based on the probe packet for the server (step S11).

The cloud server delay time measurement unit 16 updates the transfer delay information of the cloud server for each area (e.g., the measurement results in Figure 4) based on the measured first transfer delay time (step S12).

The cloud server transfer delay measurement process is performed periodically or according to a predetermined schedule.

[Second Transfer Delay Time Measurement Process]
Next, a description will be given of the second transfer delay time measurement process performed by the management device 10. Fig. 9 is a flowchart showing the processing procedure of the second transfer delay time measurement process.

The network measurement unit 17 performs a probe within the network 30 (step S21) and measures the second forwarding delay time in advance for each slice (step S22). The network measurement unit 17 updates the network delay information (e.g., FIG. 5) based on the measured second forwarding delay time (step S23).

[End-to-end delay measurement process]
Next, a description will be given of the end-end delay calculation process performed by the management device 10. Fig. 10 is a flowchart showing the procedure of the end-end delay calculation process.

In the management device 10, the end-end delay calculation unit 18 selects a logical path (step S31). For the flow information of the selected logical path, the flow information management unit 14 extracts the dst address of the acquired data (step S32) and detects the area of the cloud server for which the end-end transfer delay time is to be calculated (step S33).

The end-end delay calculation unit 18 refers to the delay time measurement results between the cloud server and the network edge node (e.g., the measurement results in Figure 4) (step S34) and obtains the first forwarding delay time for the area detected in step S33.

The end-end delay calculation unit 18 refers to the NW delay time measurement results (e.g., the measurement results in Figure 5) (step S35) and obtains a second transfer delay time corresponding to the slice for which the end-end transfer delay time is to be calculated.

Then, the end-end delay calculation unit 18 calculates the end-end delay time by adding together a value based on the first transfer delay time obtained in step S34 and the second transfer delay time obtained in step S35 (step S36).

[Effects of the embodiment]
11 and 12 are diagrams for explaining an existing method for monitoring a network in the prior art.

In a method for monitoring a network in which network slices are configured by SRs, the router section of the SR is monitored using SR probe packets (Figure 11 (1)). Therefore, this method cannot monitor using probe packets (HTTP, etc.) in the section from the node of the network edge to the server other than the router section of the SR (Figure 11 (2)). Furthermore, this method cannot monitor end-to-end network quality in the end-to-end network slice between the UE and the server (Figure 11 (3)).

It is also possible to measure delay times from a UE to a server using probe packets such as HTTP. However, if there are a large number of communication destination servers, the number of measurement targets becomes enormous (Figure 12 (1)), and there is a problem that measuring the network quality to all of the servers consumes a large amount of resources. In addition, there is a problem that, because there are a large number of UEs, probe packets from the UEs cause congestion in the network (Figure 12 (2)).

In response to this, the management device 10 according to the embodiment acquires the first forwarding delay time in advance for each area based on the communication information of the probe packet transmitted from the edge node of the NW 30 to the cloud server representing each area. The management device 10 performs a probe within the NW 30 and acquires the second forwarding delay time for each slice.

Then, the management device 10 adds up the value of the first transfer delay time obtained, which is based on the first transfer delay time of the area corresponding to the end-end of the target of calculation, and the second transfer delay time of the slice corresponding to the end-end of the target of calculation, which is obtained from the second transfer delay time obtained, and regards the added time as the end-end transfer delay time.

In this way, the management device 10 acquires the first forwarding delay time and the second forwarding delay time in advance, and simply adds up the first forwarding delay time and the second forwarding delay time in correspondence with the end-end slice and area to be measured, thereby realizing measurement of the network quality passing through the slice of NW30, the node of the NW30 edge, and the cloud server 40 corresponding to the end-end to be calculated.

In addition, since the management device 10 only needs to measure the transfer delay time to the representative cloud server for each area, it is possible to reduce network resource consumption due to quality measurement compared to a method that measures the transfer delay time for all servers.

In addition, the management device 10 applies either the average value of the first transfer delay time or the maximum value of the first transfer delay time as a time based on the first transfer delay time depending on the quality requirements of the slice corresponding to the end-to-end target of calculation. The management device 10 can appropriately manage the operation status of the service by calculating the end-to-end transfer delay time depending on the severity of the transfer delay of the service corresponding to the slice to be calculated.

[System Configuration of the Embodiment]
Each component of the management device 10 is a conceptual function, and does not necessarily have to be physically configured as shown in the figure. In other words, the specific form of distribution and integration of the functions of the management device 10 is not limited to that shown in the figure, and all or part of it can be functionally or physically distributed or integrated in any unit depending on various loads, usage conditions, etc.

In addition, each process performed in the management device 10 may be realized, in whole or in part, by a CPU, a GPU (Graphics Processing Unit), and a program analyzed and executed by the CPU and the GPU. In addition, each process performed in the management device 10 may be realized as hardware using wired logic.

Furthermore, among the processes described in the embodiments, all or part of the processes described as being performed automatically can be performed manually. Alternatively, all or part of the processes described as being performed manually can be performed automatically using known methods. In addition, the information including the processing procedures, control procedures, specific names, various data, and parameters described above and illustrated in the drawings can be changed as appropriate unless otherwise specified.

[program]
13 is a diagram showing an example of a computer in which a program is executed to realize the management device 10. The computer 1000, for example, has a memory 1010 and a CPU 1020. The computer 1000 also has a hard disk drive interface 1030, a disk drive interface 1040, a serial port interface 1050, a video adapter 1060, and a network interface 1070. These components are connected by a bus 1080.

The memory 1010 includes a ROM 1011 and a RAM 1012. The ROM 1011 stores a boot program such as a BIOS (Basic Input Output System). The hard disk drive interface 1030 is connected to a hard disk drive 1031. The disk drive interface 1040 is connected to a disk drive 1041. A removable storage medium such as a magnetic disk or optical disk is inserted into the disk drive 1041. The serial port interface 1050 is connected to a mouse 1110 and a keyboard 1120, for example. The video adapter 1060 is connected to a display 1130, for example.

The hard disk drive 1031 stores, for example, an OS (Operating System) 1091, an application program 1092, a program module 1093, and program data 1094. That is, the program that defines each process of the management device 10 is implemented as a program module 1093 in which code executable by the computer 1000 is written. The program module 1093 is stored, for example, in the hard disk drive 1031. For example, the program module 1093 for executing a process similar to the functional configuration of the management device 10 is stored in the hard disk drive 1031. The hard disk drive 1031 may be replaced by an SSD (Solid State Drive).

In addition, the setting data used in the processing of the above-described embodiment is stored as program data 1094, for example, in memory 1010 or hard disk drive 1031. Then, the CPU 1020 reads out the program module 1093 or program data 1094 stored in the memory 1010 or hard disk drive 1031 into the RAM 1012 as necessary and executes it.

Note that the program module 1093 and the program data 1094 are not limited to being stored in the hard disk drive 1031, but may be stored in, for example, a removable storage medium and read by the CPU 1020 via the disk drive 1041 or the like. Alternatively, the program module 1093 and the program data 1094 may be stored in another computer connected via a network (such as a local area network (LAN) or wide area network (WAN)). The program module 1093 and the program data 1094 may then be read by the CPU 1020 from the other computer via the network interface 1070.

The above describes an embodiment of the invention made by the inventor, but the present invention is not limited to the description and drawings that form part of the disclosure of the present invention according to this embodiment. In other words, other embodiments, examples, operational techniques, etc. made by those skilled in the art based on this embodiment are all included in the scope of the present invention.

10 Management device 20 UE (User Equipment)
30 NW (Network)
40 Cloud server 11 Network topology management unit 12 Area unit cloud server management unit 13 Flow information acquisition unit 14 Flow information management unit 15 Server measurement unit 16 Cloud server delay time measurement unit 17 NW measurement unit 18 End-to-end delay calculation unit

Claims (5)

A management device that calculates an end-to-end transfer delay time, which is a transfer delay time from a network edge node to which a UE (User Equipment) is connected in a network, and a transfer delay time from the network edge node to a cloud server,
a first acquisition unit that acquires in advance for each area a first transfer delay time, which is a transfer delay time from a network edge node to a representative cloud server of each area, based on communication information of a probe packet transmitted from the network edge node to the representative cloud server;
A second acquisition unit that performs intra-network probing and acquires a second transfer delay time, which is a transfer delay time in the network, for each slice;
a calculation unit that sums up a value based on a first transfer delay time of an area corresponding to the end-to-end of a calculation target among the first transfer delay times acquired by the first acquisition unit and a second transfer delay time of a slice corresponding to the end-to-end of the calculation target among the second transfer delay times acquired by the second acquisition unit, and determines the sum as the end-to-end transfer delay time;
A management device comprising: The management device described in claim 1, characterized in that the calculation unit applies, as a value based on the first transfer delay time, either the average value of the first transfer delay time or the maximum value of the first transfer delay time calculated based on the deviation and average value of the first transfer delay time. The management device described in claim 2, characterized in that the calculation unit applies, as a time based on the first transfer delay time, either an average value of the first transfer delay time or a maximum value of the first transfer delay time calculated based on the deviation and average value of the first transfer delay time, depending on the quality requirements of the slice corresponding to the end-end to be calculated. A management method executed by a management device that calculates an end-to-end transfer delay time, which is a transfer delay time in a network from a node at a network edge to which a UE (User Equipment) is connected, and a transfer delay time from the node at the network edge to a cloud server,
a first acquisition step of acquiring, in advance for each area, a first transfer delay time, which is a transfer delay time from a network edge node to a representative cloud server of each area, based on communication information of a probe packet transmitted from the network edge node to the representative cloud server;
A second acquisition step of performing intra-network probing to acquire a second transfer delay time, which is a transfer delay time in the network, for each slice;
a calculation step of adding up a value based on a first transfer delay time of an area corresponding to the end-to-end of a calculation target among the first transfer delay times acquired in the first acquisition step and a second transfer delay time of a slice corresponding to the end-to-end of the calculation target among the second transfer delay times acquired in the second acquisition step, and determining the sum as the end-to-end transfer delay time;
A management method comprising the steps of: a first acquisition step of acquiring, in advance for each area, a first transfer delay time, which is a transfer delay time from a network edge node to a representative cloud server of each area, based on communication information of a probe packet transmitted from the network edge node to the representative cloud server;
A second acquisition step of performing intra-network probing to acquire a second transfer delay time, which is a transfer delay time in the network from the node at the network edge, for each slice;
a calculation step of adding up a value based on a first transfer delay time of an area corresponding to an end-end from a network edge node to which a UE (User Equipment) that is a target for calculating the transfer delay time is connected to a cloud server, out of the first transfer delay time acquired in the first acquisition step, and a second transfer delay time of a slice corresponding to the end-end that is the target for calculation, out of the second transfer delay time acquired in the second acquisition step, and determining the summed time as the end-end transfer delay time;
A management program for causing a computer to execute the above.

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