Delay control system and delay control method

Abstract

Each delay control device (1) of a delay control system (1000) comprises: a delay amount storage unit (100) in which a maximum delay amount between a central computer system (30) and a user system (20) is stored; a delay amount measurement unit (110) which measures an actual delay amount; a delay sharing unit (120) which notifies another delay control device (1) of delay information including the actual delay amount, acquires delay information from the other delay control device (1), and if the actual delay amount is greater than the maximum delay amount, repeats, for each predetermined first period, a process of updating the maximum delay amount with the actual delay amount; and a delay adjustment unit (130) which repeats, for each predetermined second period, a process of adjusting the delay amount between the user system (20) and the central computer system (30) so as to be the maximum delay amount.

Description

Delay control system and delay control method

[0001] The present invention relates to a delay control system and a delay control method for controlling delays between users in a network.

[0002] Delay control is used as a technology to provide fair delays among users in network services such as e-sports, remote performances, securities trading, and telemedicine. For example, in a securities trading system, as shown in FIG. 14, fair delays are achieved by using delay control devices on each investor's terminal when trading each stock (stock X, Y). When a certain investor (investor C) changes stocks and changes path settings, new delay control must be performed. Therefore, as the scale of the network being controlled expands, delay control involving changes in path settings is expected to occur frequently. Furthermore, in a telemedicine system, such as that shown in FIG. 15, when switching from a working system to a redundant system, instantaneous delay adjustment is required to avoid affecting operations.

[0003] Patent Literature 1 discloses an information processing system including a delay measurement device that measures the amount of transmission delay occurring between each user's input / output device and a central computer, and a delay adjustment device that adjusts the difference in transmission delay between users based on the measured amount of transmission delay so as to maintain it within a predetermined value. This information processing system can reduce the difference in delay between users when using a packet-switched network such as the Internet on a network, even when the amount of delay varies due to a service provider or external factors.

[0004] International Publication No. 2022 / 070247

[0005] In order to constantly maintain the delay difference between users within a predetermined value, it is necessary to measure and adjust the delay whenever a change in path setting or topology occurs in the network. In a network where such changes occur frequently, if delay measurement and delay adjustment are performed manually, an operator's operation is required every time a change is made, resulting in high operational costs. Even in the technology described in Patent Document 1, the timing of executing delay measurement is not considered, and it does not support automation without operator operation.

[0006] The present invention has been made in view of the above points, and an object of the present invention is to automatically set the amount of delay even when the path or topology in the network is changed.

[0007] The delay control system of the present invention is a delay control system that controls delays of multiple paths established between a central computer system and each of multiple user systems, and is provided with a delay control device for each of the multiple paths, on at least one of the central computer system side or the user system side, which is the destination of transmission and reception of the multiple paths, that controls the delay of the path. Each delay control device is characterized by comprising: a delay amount storage unit in which a maximum delay amount between the central computer system and the user system is stored; a delay amount measurement unit that measures the delay amount between the user system on which it resides and the central computer system as an actual delay amount; a delay sharing unit that repeats a delay sharing phase, which is a process of notifying other delay control devices other than itself of delay information including the actual delay amount, acquiring delay information including the actual delay amount from the other delay control devices, and updating the maximum delay amount with the actual delay amount if the actual delay amount is greater than the maximum delay amount stored in the delay amount storage unit, for each predetermined first period; and a delay adjustment unit that repeats a delay adjustment phase, which is a process of adjusting the delay amount between the user system on which it resides and the central computer system so that it becomes the maximum delay amount stored in the delay amount storage unit, for each predetermined second period.

[0008] According to the present invention, even if the path or topology in the network is changed, the delay amount can be automatically set.

[0009] FIG. 1 is a diagram illustrating the overall configuration of a delay control system including a delay control device according to the present embodiment. FIG. 2 is a functional block diagram illustrating the configuration of the delay control device according to the present embodiment. FIG. 3 is a diagram illustrating a delay sharing phase in the delay control system according to the present embodiment. FIG. 4 is a diagram illustrating an automatic delay adjustment process executed by the delay control system according to the present embodiment. FIG. 5 is a diagram illustrating the delay adjustment phase in the delay control system according to the present embodiment. FIG. 6 is a flowchart illustrating a processing flow in the delay sharing phase executed by the delay control device according to the present embodiment. FIG. 7 is a flowchart illustrating a processing flow in the delay adjustment phase executed by the delay control device according to the present embodiment. FIG. 8 is a diagram illustrating the overall configuration and delay sharing phase of a delay control system including a delay control device according to a modified example of the present embodiment. FIG. 9 is a functional block diagram illustrating the configuration of a delay control device according to a modified example of the present embodiment. FIG. 10 is a diagram illustrating the delay adjustment phase in the delay control system according to the modified example of the present embodiment. FIG. 11 is a sequence diagram illustrating a processing flow in the delay sharing phase executed by the delay control device and the delay adjustment device according to the modified example of the present embodiment. FIG. 12 is a hardware configuration diagram illustrating an example of a delay control device according to the present embodiment and a computer that realizes the functions of the delay control device according to the modified example of the present embodiment. FIG. 13 is a diagram illustrating an example of executing delay control in a securities trading system. FIG. 14 is a diagram illustrating an example of executing delay control in a remote use system.

[0010] Next, an embodiment of the present invention (hereinafter referred to as "this embodiment") will be described. A delay control device 1 according to this embodiment (see FIG. 2 described later) periodically measures the amount of delay when no delay is added, and notifies the other delay control devices 1 of the measured amount of delay. Each delay control device 1 then determines the maximum delay amount of the path group based on the received delay amount, and automatically adjusts the delay of each path to the determined maximum delay amount.

[0011] Fig. 1 is a diagram showing the overall configuration of a delay control system 1000 including a delay control device 1 according to this embodiment. As shown in Fig. 1, the delay control system 1000 includes user systems 20 (20-1, 20-2, 20-3, 20-4) and a central computer system 30. Note that the number of user systems 20 is not limited to the four systems shown in Fig. 1, and it is sufficient if multiple user systems 20 are included.

[0012] Each user system 20 includes, for example, an input / output device 21, an input / output management device 22, and a delay control device 1. Here, the delay control device 1 included in user system 20-1 is referred to as the "delay control device 1-1," the delay control device 1 included in user system 20-2 is referred to as the "delay control device 1-2," and similarly, the delay control devices 1 included in user systems 20-3 and 20-4 are referred to as the "delay control devices 1-3 and 1-4." Each user system 20 includes a signal transmission / reception device (not shown), and is connected to the central computer system 30 via a path setting in the network between them. Furthermore, each user system 20 is connected to the other user systems 20 via a network or the like.

[0013] The input / output device 21 is, for example, an image display device, a keyboard, a game controller, a tablet, a speaker, etc. The input / output device 21 is connected to an input / output management device 22. The input / output management device 22 manages the output of information to the input / output device 21, the output of information from the input / output device 21, etc. The input / output management device 22 is connected to the delay control device 1.

[0014] The delay control device 1 measures the amount of delay occurring between the central computer system 30 and the user system 20, and notifies delay information indicating the measured amount of delay to delay control devices 1 provided in other user systems 20 other than its own user system 20. Then, based on the notified amount of delay, the delay control device 1 determines the maximum amount of delay and sets the delay of each path to the maximum amount of delay, thereby adjusting the amount of delay between the central computer system 30. Details will be described later. The delay control device 1 transmits and receives signals to and from the central computer system 30 via a signal transmission / reception device (not shown). The delay control device 1 also transmits and receives delay information, etc. to and from other user systems 20 via the signal transmission / reception device.

[0015] Next, we will explain the central computer system 30. The central computer system 30 includes a central computer 31, signal transmission / reception devices (not shown) corresponding to the user systems 20 (20-1, 20-2, 20-3, 20-4), and delay control devices 3 (delay control devices 3-1, 3-2, 3-3, 3-4) connected to the signal transmission / reception devices.

[0016] The central computer 31 is, for example, a server, and executes processing to provide services in response to requests from the user system 20. These services are, for example, the above-mentioned network services such as E-Sports, remote performances, securities trading, and remote medical care.

[0017] The delay control device 3 transmits and receives information between the central computer 31 and each user system 20 via a signal transmission / reception device (not shown). The delay control device 3 also measures the amount of delay occurring between the central computer system 30 and each user system 20, and notifies the other delay control devices 3 of delay information indicating the measured amount of delay. The delay control device 3 then determines the maximum amount of delay based on the notified amount of delay, sets the delay of each path to the maximum amount of delay, and adjusts the amount of delay between each user system 20.

[0018] In the example of FIG. 1, both communication sections are equipped with a "delay control device" for measuring and adjusting delays on the signal receiving side, but the configuration is not limited to this. For example, in a use case where delay adjustment is performed only in one direction (such as video distribution), the delay control device 3 on the transmitting side may be omitted. Furthermore, if the delay control device 1 on the user system 20 side can control the delay between the central computer system 30 in both directions, the delay control device 3 on the central computer system 30 side may be omitted, and only the delay control device 1 on the user system 20 side may be provided. In other words, it is sufficient that at least one of the central computer system 30 side or the user system 20 side, which is the destination of multiple paths, is provided with a delay control device 1 or 3 for each path to control the delay of the path. Furthermore, the delay control devices 1 and 3 are not limited to devices in a single housing, but may be implemented, for example, as an internal function of a signal transmitting / receiving device or an input / output management device 22, or as an application.

[0019] <Delay Control Device> Next, we will explain the details of the delay control devices 1 and 3. Since the delay control devices 1 and 3 have similar functions on the user system 20 side and the central computer system 30 side, we will explain the delay control device 1 provided in the user system 20 as a representative.

[0020] FIG. 2 is a functional block diagram showing the configuration of the delay control device 1 according to this embodiment. The delay control device 1 realizes automatic delay adjustment processing by periodically executing a "delay sharing phase" and a "delay adjustment phase," which will be described in detail later. In the "delay sharing phase," each delay control device 1 measures the actual path delay amount (hereinafter sometimes referred to as "actual delay amount") without added delay and notifies each other of the measured delay amount. Then, if the received delay amount is greater than the stored delay amount (stored delay amount), each delay control device 1 updates the stored delay amount with the received delay amount. As a result, each delay control device 1 notifies each other of the path delay amount and holds the maximum delay amount (maximum delay amount) as the stored delay amount. In the "delay adjustment phase," each delay control device 1 adjusts the path delay between the user system 20 and the central computer system 30 to the stored maximum delay amount (maximum delay amount).

[0021] In the delay control system 1000, each delay control device 1 periodically repeats the "delay sharing phase" and "delay adjustment phase" to set the delay of each path to the maximum delay amount. This makes it possible to automatically set the delay amount even if the network path or topology changes, thereby reducing the maintenance work required by operators. The delay control device 1 will be described in detail below.

[0022] As shown in FIG. 2, the delay control device 1 according to this embodiment includes a control unit 10, an input / output unit 11, and a storage unit 12.

[0023] The input / output unit 11 inputs and outputs information via a signal transmission / reception device (not shown) between the central computer system 30 and other user systems 20. This input / output unit 11 is composed of a communication interface that transmits and receives information via a communication line, and an input / output interface that inputs and outputs information between an input device such as a keyboard and an output device such as a monitor, both not shown.

[0024] The storage unit 12 is configured with a hard disk, flash memory, RAM (Random Access Memory), etc. This storage unit 12 has a delay amount storage unit 100, which stores the maximum delay amount (maximum delay amount) among the delay amounts measured by its own delay control device 1 and the delay amounts received from other delay control devices 1 other than its own delay control device 1. In addition, this storage unit 12 temporarily stores information necessary for processing by the control unit 10.

[0025] The control unit 10 controls all of the processes executed by the delay control device 1, and includes a delay amount measurement unit 110, a delay sharing unit 120, and a delay adjustment unit .

[0026] The delay measurement unit 110 measures the delay between its own user system 20 and the central computer system 30. Here, the delay measurement unit 110 measures the delay (actual delay) of an actual path where no delay has been added between the user system 20 and the central computer system 30, i.e., where no delay adjustment has been performed. Note that paths are set between each user system 20 and the central computer system 30 as shown in FIG. 3 . The administrator of the delay control system 1000 assigns the same ID (path ID) to paths to be adjusted to have the same delay. Here, it is assumed that "1" is assigned as the path ID for adjusting the paths between the user systems 20-1, 20-2, and 20-4 and the central computer system 30 to have the same delay. It is also assumed that the path ID "2" is assigned to the path between the user system 20-3 and the central computer system 30. Note that the values ​​in the square boxes in FIG. 3 indicate path IDs.

[0027] When the delay amount measurement unit 110 measures the delay amount (actual delay amount) of a path, it outputs the delay amount of the path and information on the path ID of the path to the delay sharing unit 120 .

[0028] The delay sharing unit 120 generates delay information including the measured path delay amount (actual delay amount) and path ID information, and notifies the generated delay information to the delay control device 1 of each user system 20. For example, the delay control device 1-1 of user system 20-1 notifies the delay control device 1-2 of user system 20-2, the delay control device 1-3 of user system 20-3, and the delay control device 1-4 of user system 20-4 of the delay information. The delay sharing unit 120 also stores the path delay amount (actual delay amount) acquired from the delay amount measurement unit 110 in the delay amount storage unit 100 in the memory unit 12. Note that if a delay amount (maximum delay amount) has already been stored in the delay amount storage unit 100, the delay sharing unit 120 updates the stored delay amount with the actual delay amount if the actual delay amount is greater than the stored delay amount.

[0029] When the delay sharing unit 120 acquires delay information from the delay control devices 1 (1-2, 1-3, 1-4) of other user systems 20 other than itself, it determines whether the path ID between its own user system 20 and the central computer system 30 is the same as the path ID attached to the delay information. If the path IDs are the same, the delay sharing unit 120 compares the delay amount (actual delay amount) attached to the received delay information with the delay amount (stored delay amount) stored in the delay amount storage unit 100, and if the received delay amount is greater than the stored delay amount, it updates the stored delay amount with the received delay amount. In other words, the delay control devices 1 notify each other of the path delay amounts and store the largest delay amount (maximum delay amount) in the delay amount storage unit 100.

[0030] The measurement of the path delay amount by the delay amount measurement unit 110, the notification of delay information by the delay sharing unit 120 to each delay control device 1, and the storage of the delay amount (maximum delay amount) of the same path group in the delay amount storage unit 100 are repeated every first period (delay sharing period: predetermined first period), which is a preset time interval. This series of processes is the "delay sharing phase."

[0031] The delay adjustment unit 130 refers to the delay amount (maximum delay amount) stored in the delay amount storage unit 100 at every second period (delay adjustment period: predetermined second period), which is a preset time interval, and adjusts the delay between the central computer system 30 to the delay amount (maximum delay amount) stored in the delay amount storage unit 100. Thereafter, the delay adjustment unit 130 initializes the stored delay amount to "0." This series of processes is the "delay adjustment phase."

[0032] Since it is necessary to receive delay information from all delay control devices 1 within the delay adjustment period of the delay adjustment phase, the delay adjustment period is set to a period longer than the delay sharing period.

[0033] Next, the automatic delay adjustment process of the delay control system 1000 as a whole will be described. Figure 4 is a diagram illustrating the automatic delay adjustment process executed by the delay control system 1000 according to this embodiment. The automatic delay adjustment process is realized by each delay control device 1 performing a delay sharing phase and a delay adjustment phase for each delay sharing period and delay adjustment period. Note that Figure 4 illustrates delay control devices 1-1, 1-2, and 1-4 to which the same path ID "1" is assigned, and omits the illustration of delay control device 1-3 to which path ID "2" is assigned, since the stored delay amount is not updated due to a different path ID.

[0034] In Figure 4, for example, when the delay control device 1-1 is started up or the path setting is changed, the delay control device 1-1 starts the delay sharing phase with the current time set to time A and notifies each delay control device 1-2, 1-4 of the measured delay amount. Then, the delay control device 1-1 repeats the delay sharing phase in the delay sharing period. Also, when the current time set to time B, the delay control device 1-1 starts the delay adjustment phase and adjusts the delay amount set in the path to the stored delay amount (maximum delay amount). Then, the delay control device 1-1 repeats the delay adjustment phase in the delay adjustment period. The delay sharing phase and delay adjustment phase are executed periodically by each delay control device 1.

[0035] For example, as shown in FIG. 3, if the set delay adjusted for path ID "1" is "30 ms," then during the delay sharing phase, the delay (actual delay) measured by delay control device 1-1 is <20 ms> (symbol a1), the delay (actual delay) measured by delay control device 1-2 is <30 ms> (symbol b1), and the delay (actual delay) measured by delay control device 1-4 is <40 ms> (symbol d1). In this case, as shown in FIG. 5, during the delay adjustment phase, the maximum delay "40 ms" (symbol x) stored in the delay amount storage unit 100 of each delay control device 1-1, 1-2, and 1-4 is adjusted to become the delay (set delay) of the path. Note that the "set delay <actual delay>" is indicated within the dashed line frames in FIGS. 3 and 5.

[0036] <Processing of Delay Control Device> Next, processing executed by the delay control device 1 according to this embodiment will be described.

[0037] [Processing in the Delay Sharing Phase] FIG. 6 is a flowchart showing the flow of processing in the delay sharing phase executed by the delay control device 1 according to this embodiment.

[0038] This delay sharing phase is initiated by starting up the delay control device 1 or by changing the path settings. It is also assumed that paths are established between the central computer system 30 and each user system 20, and that path IDs indicating the path groups set to achieve fair delays are set in advance.

[0039] First, the delay sharing unit 120 of the delay control device 1 stores the current time in the storage unit 12 as time A, which is the reference time of the delay sharing period (step S10).

[0040] Next, the delay sharing unit 120 issues an instruction to the delay amount measurement unit 110, which then measures the delay amount (actual delay amount) of the path set between its own user system 20 and the central computer system 30 (step S11). Here, the delay amount measurement unit 110 measures the actual path delay amount (actual delay amount) with no delay added between the user system 20 and the central computer system 30, that is, with no delay adjustment performed. After measuring the actual delay amount, the delay amount measurement unit 110 outputs the delay amount and path ID information to the delay sharing unit 120.

[0041] The delay sharing unit 120 generates delay information including the measured path delay amount (actual delay amount) and path ID information, and notifies the generated delay information to the delay control devices 1 of all user systems 20 (step S12). Furthermore, if the measured actual delay amount is greater than the stored delay amount, the delay sharing unit 120 updates the stored delay amount with the actual delay amount and stores it in the delay amount storage unit 100.

[0042] Next, the delay sharing unit 120 receives delay information including information on the actual delay amount and path ID from each delay control device 1 (step S13). Then, the delay sharing unit 120 determines whether the path ID included in the delay information matches the path ID set for itself (step S14). If they match (step S14 → Yes), the delay sharing unit 120 proceeds to the next step S15.

[0043] In step S15, the delay sharing unit 120 compares the actual delay amount attached to the received delay information with the delay amount (stored delay amount) stored in the delay amount storage unit 100, and if the actual delay amount is greater than the stored delay amount, updates the stored delay amount (maximum delay amount) with the actual delay amount. This allows the delay sharing unit 120 to store the maximum delay amount of the actual delay amount measured by the delay amount measurement unit 110 and the actual delay amount acquired as delay information from the other delay control device 1 in the delay amount storage unit 100 as the stored delay amount. Then, the process proceeds to the next step S16.

[0044] On the other hand, if the path IDs do not match in step S14 (step S14→No), the process of step S15 is not performed and the process proceeds to the next step S16.

[0045] In step S16, the delay sharing unit 120 waits until the time equal to time A plus the delay sharing period has elapsed. Then, when the delay sharing period has elapsed, the process returns to step S10, and the current time is set as time A, which is the reference time of the delay sharing period, and the process continues.

[0046] 7 is a flowchart showing the flow of processing in the delay adjustment phase executed by the delay control device 1 according to this embodiment. This delay adjustment phase is initiated when the delay control device 1 is started or when the path setting is changed.

[0047] First, the delay adjustment unit 130 of the delay control device 1 stores the current time in the storage unit 12 as time B, which is the reference time of the delay adjustment period (step S20).

[0048] Next, the delay adjustment unit 130 adjusts the delay of the path set between its own user system 20 and the central computer system 30 so that it becomes the stored delay amount (maximum delay amount) stored in the delay amount storage unit 100 (step S21).

[0049] Next, the delay adjustment unit 130 resets the stored delay amount (maximum delay amount) stored in the delay amount storage unit 100 to 0 (step S22).

[0050] Next, the delay adjustment unit 130 waits until the time equal to time B plus the delay adjustment period arrives (step S23). Then, when the delay adjustment period has elapsed, the process returns to step S20, and the current time is set as time B, which is the reference time for the delay adjustment period, and the process continues.

[0051] Each delay control device 1 executes the processes of the delay sharing phase and the delay adjustment phase, respectively. As a result, the delay control system 1000 determines the maximum delay amount of a group of paths that are to be adjusted as the same delay, and the delay control device 1 can automatically adjust the delay of each path to the maximum delay amount.

[0052] Next, a delay control system 1000A including a delay control device 1A according to a modification of this embodiment will be described. The delay control system 1000A according to this modification of this embodiment differs from the delay control system 1000 shown in FIG. 1 in that it includes a delay adjustment device 4. The delay adjustment device 4 acquires information on measured delay amounts (actual delay amounts) from each delay control device 1A (3A) and transmits the acquired actual delay amounts to delay control devices 1A (3A) belonging to a path group to be adjusted with the same delay amount during the "delay sharing phase." When a delay control device 1A (3A) receives the actual delay amounts of other delay control devices 1A (3A) via the delay adjustment device 4, if the received delay amount is greater than the stored delay amount, the delay control device 1A (3A) updates the stored delay amount with the received delay amount, thereby storing the maximum delay amount in the delay amount storage unit 100. During the "delay adjustment phase," each delay control device 1A (3A) automatically adjusts the delay of each path to the stored delay amount (maximum delay amount) stored in the delay amount storage unit 100.

[0053] 8 is a diagram showing the overall configuration of a delay control system 1000A including a delay control device 1A according to a modified example of this embodiment. Components having the same functions as those of the delay control system 1000 shown in FIG. 1 are given the same names and symbols, and detailed descriptions thereof will be omitted.

[0054] As shown in FIG. 8, the delay control system 1000A includes user systems 20 (20-1, 20-2, 20-3, 20-4), a central computer system 30, and a delay adjustment device 4.

[0055] Each user system 20 includes, for example, an input / output device 21, an input / output management device 22, and a delay control device 1A. Here, the delay control device 1A included in user system 20-1 is referred to as the "delay control device 1A-1," the delay control device 1A included in user system 20-2 is referred to as the "delay control device 1A-2," and similarly, the delay control devices 1A included in user systems 20-3 and 20-4 are referred to as the "delay control devices 1A-3 and 1A-4." Each user system 20 includes a signal transmission / reception device (not shown), and is connected to the central computer system 30 via a path setting in the network between them. Furthermore, each user system 20 is connected for communication with the delay adjustment device 4 via a network or the like.

[0056] The delay control device 1A measures the amount of delay occurring between the central computer system 30 and the user system 20, and notifies the delay adjustment device 4 of delay information indicating the measured amount of delay. Then, based on the amount of delay (actual delay amount) received from the delay adjustment device 4, the delay control device 1A determines the maximum amount of delay, sets the path delay to the maximum amount of delay, and adjusts the amount of delay between the delay control device 1A and the central computer system 30. The delay control device 1A transmits and receives signals to and from the central computer system 30 via a signal transmission / reception device (not shown). The delay control device 1A also transmits and receives delay information and the like to and from the delay adjustment device 4 via the signal transmission / reception device.

[0057] The central computer system 30 comprises a central computer 31, signal transmission / reception devices (not shown) corresponding to the user systems 20 (20-1, 20-2, 20-3, 20-4), and delay control devices 3A (delay control devices 3A-1, 3A-2, 3A-3, 3A-4) connected to each signal transmission / reception device.

[0058] The delay control device 3A transmits and receives information between the central computer 31 and each user system 20 via a signal transmission / reception device (not shown). The delay control device 3A also measures the amount of delay occurring between the central computer system 30 and each user system 20, and notifies the delay adjustment device 4 of delay information indicating the measured amount of delay. The delay control device 3A then determines the maximum amount of delay based on the amount of delay received from the delay adjustment device 4, sets the delay of each path to the maximum amount of delay, and adjusts the amount of delay between each user system 20.

[0059] The delay adjustment device 4 acquires delay information from each delay control device 1A, 3A, including the measured delay amount (actual delay amount) between the user system 20 and the central computer system 30. The delay adjustment device 4 then transmits the delay information including the acquired actual delay amount to other delay control devices 1A (3A) in the path group to which the delay control device 1A (3A) that transmitted the delay information belongs and which is to be adjusted as the same delay. The delay control device 1A (3A) and the delay adjustment device 4 will be described in detail below.

[0060] <Delay control device 1A> First, we will explain the details of the delay control devices 1A and 3A. Note that the delay control devices 1A and 3A have similar functions on the user system 20 side and the central computer system 30 side, so we will explain the delay control device 1A provided in the user system 20 as a representative.

[0061] 9 is a functional block diagram showing the configuration of a delay control device 1A according to a modified example of this embodiment. Components having the same functions as those of the delay control device 1 shown in FIG. 2 are given the same names and symbols, and detailed descriptions thereof will be omitted. Similar to the delay control device 1 (FIG. 2), the delay control device 1A realizes automatic delay adjustment processing by periodically executing a "delay sharing phase" and a "delay adjustment phase."

[0062] The delay measurement unit 110A measures the delay between its own user system 20 and the central computer system 30. Here, the delay measurement unit 110A measures the actual path delay without adding delay between the user system 20 and the central computer system 30, i.e., without delay adjustment. Paths are set between each user system 20 and the central computer system 30 as shown in FIG. 8. The administrator of the delay control system 1000A assigns the same ID (path ID) to paths to be adjusted to have the same delay. Here, it is assumed that "1" is assigned as the path ID for adjusting the paths between the user systems 20-1, 20-2, and 20-4 and the central computer system 30 to have the same delay. It is also assumed that the path ID "2" is assigned to the path between the user system 20-3 and the central computer system 30.

[0063] After measuring the delay amount of the path, the delay amount measuring unit 110A outputs information on the delay amount of the path to the delay sharing unit 120A.

[0064] The delay sharing unit 120A generates delay information including information on the measured path delay amount, and notifies the generated delay information to the delay adjustment device 4. The delay sharing unit 120A also stores the path delay amount acquired from the delay amount measurement unit 110A in the delay amount storage unit 100 in the memory unit 12. In the example shown in FIG. 8, for example, the delay sharing unit 120A of the delay control device 1A-1 stores "20 ms" as the actual delay amount.

[0065] 8, it is assumed that the delay amounts (actual delay amounts) measured by the delay amount measuring units 110A of the delay control devices 1A (1A-1, 1A-2, 1A-3, 1A-4) are 20 ms, 30 ms, 20 ms, and 40 ms, respectively. At this time, the delay sharing units 120A of the delay control devices 1A (1A-1, 1A-2, 1A-3, 1A-4) transmit delay information including information on the measured actual delay amounts to the delay adjustment device 4.

[0066] The delay sharing unit 120A then receives from the delay adjustment device 4 the delay amounts of paths measured by other delay control devices 1A of the paths to be adjusted as the same delay. Next, the delay sharing unit 120A compares the delay amount attached to the received delay information with the delay amount (stored delay amount) stored in the delay amount storage unit 100, and if the received delay amount is greater than the stored delay amount, updates the stored delay amount with the received delay amount. In other words, the delay control device 1A obtains the delay amounts of the same path group from the delay adjustment device 4 and stores the largest delay amount (maximum delay amount) in the delay amount storage unit 100.

[0067] In the example shown in Figure 8, for example, the delay sharing unit 120A of the delay control device 1A-1 acquires information on the delay amount (actual delay amount) measured by its own delay control device 1A-1 (delay amount measurement unit 110A) <20 ms> (symbol a1) as the delay amount of the same path group, and information on the delay amount (actual delay amount) measured by the delay control devices 1A-2 and 1A-4 (<30 ms> (symbol b2), <40 ms> (symbol d2)), and stores "40 ms" as the maximum delay amount in the delay amount storage unit 100.

[0068] The delay amount measurement unit 110A measures the path delay amount, the delay sharing unit 120A notifies the delay adjustment device 4 of the delay information, and the delay amount (maximum delay amount) of the same path group is stored in the delay amount storage unit 100. This series of processes is called the "delay sharing phase."

[0069] In addition, when the adjusted set delay amount for path ID "1" is "30 ms" (see Figure 8), as shown in Figure 10, in the delay sharing phase, when the maximum delay amount stored in the delay amount storage unit 100 of each delay control device 1A-1, 1A-2, 1A-4 becomes "40 ms" (symbol y), the delay adjustment unit 130 adjusts this "40 ms" as the current delay amount (set delay amount) of the path.

[0070] <Delay Adjustment Device> Next, the delay adjustment device will be described in detail. Fig. 11 is a functional block diagram showing the configuration of a delay adjustment device 4 according to a modification of this embodiment. As shown in Fig. 11, the delay adjustment device 4 according to the modification of this embodiment includes a control unit 40, an input / output unit 41, and a storage unit 42.

[0071] The input / output unit 41 inputs and outputs information between the user system 20, the central computer system 30, etc. This input / output unit 41 is composed of a communication interface that transmits and receives information via a communication line, and an input / output interface that inputs and outputs information between an input device such as a keyboard and an output device such as a monitor, both of which are not shown.

[0072] The storage unit 42 is configured with a hard disk, flash memory, RAM (Random Access Memory), etc. Path ID information 400 is stored in this storage unit 42 as information in which the same ID (path ID) is assigned to paths to be adjusted to have the same delay. For example, as shown in Fig. 8, this path ID information 400 stores information in which "1" is associated as the path ID to be adjusted to have the same delay for paths between the user systems 20-1, 20-2, 20-4 and the central computer system 30, and "2" is associated as the path ID for the path between the user system 20-3 and the central computer system 30.

[0073] The control unit 40 controls all the processes executed by the delay adjustment device 4 , and includes a delay information acquisition unit 410 and a delay adjustment unit 420 .

[0074] The delay information acquisition unit 410 acquires delay information including the actual delay amount from each delay control device 1A. The delay adjustment unit 420 references the path ID information 400 in the storage unit 42 and extracts the path ID of the path measured by the delay control device 1A that transmitted the delay information and other delay control devices 1A that have the same path ID. The delay adjustment unit 420 then transmits the delay information acquired by the delay information acquisition unit 410 to the extracted delay control device 1A.

[0075] As a result, the delay sharing unit 120A of the delay control device 1A does not need to determine whether the path IDs of the received delay information are the same or not, thereby reducing the processing load on the delay control device 1A.

[0076] <Processing of Delay Control Device 1A and Delay Adjustment Device> Next, we will explain the "processing of the delay sharing phase" by the delay control device 1A and the delay adjustment device 4 according to a modification of this embodiment. Note that the "processing of the delay adjustment phase" in the modification of this embodiment is the same as the processing shown in FIG. 7, so description thereof will be omitted.

[0077] 12 is a sequence diagram showing the flow of processing in the delay sharing phase executed by the delay control device 1A and delay adjustment device 4 according to a modified example of this embodiment. This delay sharing phase is initiated when the delay control device 1A is started or when the path settings are changed. It is also assumed that a path has been established between the central computer system 30 and its own user system 20, that a path ID indicating a group of paths set to achieve fair delay has been set in advance, and that this information has been stored in the delay adjustment device 4 as path ID information 400.

[0078] First, the delay sharing unit 120A (FIG. 9) of the delay control device 1A stores the current time in the storage unit 12 as time A, which is the reference time of the delay sharing period (step S30).

[0079] Next, the delay sharing unit 120A issues an instruction to the delay amount measurement unit 110A, and the delay amount measurement unit 110A measures the delay amount (actual delay amount) of the path set between its own user system 20 and the central computer system 30. Here, the delay amount measurement unit 110 measures the actual path delay amount (actual delay amount) with no delay added to the central computer system 30, that is, with no delay adjustment performed. After measuring the actual delay amount, the delay amount measurement unit 110 outputs it to the delay sharing unit 120A.

[0080] The delay sharing unit 120A generates delay information including information on the measured path delay amount (actual delay amount) and notifies the delay adjustment device 4 (step S32). Furthermore, if the measured actual delay amount is greater than the stored delay amount, the delay sharing unit 120A updates the stored delay amount with the actual delay amount and stores it in the delay amount storage unit 100.

[0081] The delay information acquisition unit 410 of the delay adjustment device 4 acquires delay information including the actual delay amount (step S33).

[0082] The delay adjustment unit 420 then refers to the path ID information, extracts the path ID of the path measured by the delay control device 1A that transmitted the delay information, and extracts other delay control devices 1A that have the same path ID. The delay adjustment unit 420 then transmits the acquired delay information to the extracted other delay control devices 1A (step S34).

[0083] Next, the delay sharing unit 120A of the delay control device 1A receives delay information of the delay control device 1 with the same path ID from the delay adjustment device 4 (step S35).The delay sharing unit 120A then compares the actual delay amount attached to the received delay information with the delay amount (stored delay amount) stored in the delay amount storage unit 100, and if the actual delay amount is greater than the stored delay amount, updates the stored delay amount (maximum delay amount) with the actual delay amount (step S36).As a result, the delay sharing unit 120A can store the maximum delay amount of the actual delay amount measured by the delay amount measurement unit 110A and the actual delay amount acquired as delay information from the other delay control device 1A in the delay amount storage unit 100 as the stored delay amount.

[0084] Next, the delay sharing unit 120A waits until the time equal to time A+the delay sharing period arrives (step S37). Then, when the delay sharing period has elapsed, the process returns to step S30, and the current time is set as time A, which is the reference time of the delay sharing period, and the process continues.

[0085] Each delay control device 1A executes the processes of the delay sharing phase and the delay adjustment phase, respectively. As a result, each delay control device 1A in the delay control system 1000A can determine the maximum delay amount of a group of paths to be adjusted as the same delay using the delay information received from the delay adjustment device 4, and the delay control device 1A can automatically adjust the delay of each path to the maximum delay amount.

[0086] <Hardware Configuration> The delay control devices 1 and 3 according to this embodiment and the delay control devices 1A and 3A according to the modified example of this embodiment are realized by a computer 900 having a configuration such as that shown in Fig. 13. Fig. 13 is a hardware configuration diagram showing an example of a computer 900 that realizes the functions of the delay control devices 1 and 1A according to this embodiment and the delay control devices 1A and 3A according to the modified example of this embodiment. The computer 900 has a CPU 901, a ROM (Read Only Memory) 902, a RAM 903, an HDD (Hard Disk Drive) 904, an input / output I / F (Interface) 905, a communication I / F 906, and a media I / F 907.

[0087] The CPU 901 operates based on a program (delay control program) stored in the ROM 902 or the HDD 904, and performs control by the control unit 10 (FIGS. 2 and 9). The ROM 902 stores a boot program executed by the CPU 901 when the computer 900 is started up, programs related to the hardware of the computer 900, and the like.

[0088] The CPU 901 controls an input device 910 such as a mouse or keyboard, and an output device 911 such as a display or printer, via an input / output I / F 905. The CPU 901 acquires data from the input device 910 via the input / output I / F 905, and outputs generated data to the output device 911. Note that a GPU (Graphics Processing Unit) or the like may be used as a processor together with the CPU 901.

[0089] The HDD 904 stores programs executed by the CPU 901 and data used by the programs. The communication I / F 906 receives data from other devices via a communication network (e.g., NW (Network) 920) and outputs the data to the CPU 901, and also transmits data generated by the CPU 901 to other devices via the communication network.

[0090] The media I / F 907 reads a program (delay control program) or data stored in the recording medium 912 and outputs it to the CPU 901 via the RAM 903. The CPU 901 loads a program related to a target process from the recording medium 912 onto the RAM 903 via the media I / F 907, and executes the loaded program. The recording medium 912 is an optical recording medium such as a DVD (Digital Versatile Disc) or a PD (Phase Change Rewritable Disc), a magneto-optical recording medium such as an MO (Magneto Optical Disc), a magnetic recording medium, a semiconductor memory, or the like.

[0091] For example, when a computer 900 functions as the delay control devices 1 and 3 according to this embodiment and the delay control devices 1A and 3A according to the modified examples of this embodiment, a CPU 901 of the computer 900 executes a program (delay control program) loaded onto a RAM 903 to realize the functions of the delay control program. Furthermore, data stored in the RAM 903 is stored in the HDD 904. The CPU 901 reads and executes a program related to a target process from a recording medium 912. Alternatively, the CPU 901 may read a program related to a target process from another device via a communication network (NW 920).

[0092] <Effects> The effects of the delay control system 1000 according to the present invention will be described below. The delay control system 1000 according to the present invention is a delay control system that controls the delay of a plurality of paths established between a central computer system 30 and each of a plurality of user systems 20, and is provided with a delay control device 1 for each path on at least one of the central computer system 30 side or the user system 20 side, which are the transmission / reception destinations of the plurality of paths, for controlling the delay of the path. Each delay control device includes a delay amount storage unit 100 that stores the maximum delay amount between the central computer system 30 and the user system 20, and a delay amount measurement unit 110 that measures the delay amount between the user system 20 and the central computer system 30 as an actual delay amount. a delay sharing section 120 that notifies other delay control devices 1 other than itself of delay information including the actual delay amount, acquires delay information including the actual delay amount from the other delay control devices 1, and repeats a delay sharing phase, which is a process of updating the maximum delay amount with the actual delay amount if the actual delay amount is greater than the maximum delay amount stored in the delay amount storage section 100, at every predetermined first period; and a delay adjustment section 130 that repeats a delay adjustment phase, which is a process of adjusting the delay amount between the user system 20 and the central computer system 30 to which it belongs, at every predetermined second period, so that the delay amount becomes the maximum delay amount stored in the delay amount storage section 100.

[0093] In this way, the delay control system 1000 can automatically adjust the delay of each path to the maximum delay amount for each path by periodically executing the processes of the delay sharing phase and the delay adjustment phase by each delay control device 1. Therefore, even if the paths or topology in the network are changed, it is possible to automatically set the delay amount of the path without any operation by an operator.

[0094] In addition, in the delay control system 1000, the same path ID is assigned to multiple paths that should be adjusted to have the same delay, and the delay sharing unit 120 notifies other delay control devices 1 other than itself of the delay information, including the path ID of the path measured by the delay amount measurement unit 110, and when it receives delay information from another delay control device 1, if the path ID of the path set between the user system 20 and the central computer system 30 to which it belongs is the same as the path ID attached to the received delay information, it determines whether the actual delay amount attached to the delay information is greater than the maximum delay amount stored in the delay amount storage unit 100.

[0095] In this way, the delay control system 1000 can automatically adjust the delay of paths that should be adjusted to have the same delay to the maximum delay amount measured in the group of paths.

[0096] Furthermore, the delay control system according to the present invention is a delay control system 1000A comprising a central computer system 30 and a delay adjustment device 4 for adjusting delays of a plurality of paths set between the central computer system 30 and each of a plurality of user systems 20, and comprising a delay control device 1A for controlling the delay of the path on at least one of the central computer system 30 side or the user system 20 side which are the transmission / reception destinations of the plurality of paths, and the delay adjustment device 4 has path ID information 400 stored in a storage unit 42 for each of the plurality of paths, the path ID information being information in which the same path ID is assigned to paths that should be adjusted with the same delay, and each delay control device 1A comprises a delay amount storage unit 100 for storing the maximum delay amount between the central computer system 30 and the user system 20, a delay amount measurement unit 110A for measuring the delay amount between the user system 20 and the central computer system 30 as an actual delay amount, and notifying the delay adjustment device 4 of delay information including the actual delay amount and the path ID of the path measured by the delay amount measurement unit 110A, and receiving from the delay adjustment device 4 the delay control device 1A. a delay sharing unit (120A) that repeats a delay sharing phase, which is a process of acquiring delay information including an actual delay amount of another path to which the same path ID as the path ID of a path set between the user system (20) and the central computer system (30) is assigned, and if the actual delay amount is greater than the maximum delay amount stored in the delay amount storage unit (100), updates the maximum delay amount with the actual delay amount, at every predetermined first period; and a delay adjustment unit (130) that repeats a delay adjustment phase, which is a process of adjusting the delay amount between the user system (20) and the central computer system (30) to be equal to the maximum delay amount stored in the delay amount storage unit (100), at every predetermined second period. The delay adjustment device (4) is characterized by comprising: a delay information acquisition unit (410) that acquires delay information from each delay control device (1A), and a delay adjustment unit (420) that refers to the path ID information (400), extracts the path ID included in the delay information and other delay control devices (1A) that measure the delay amount of a path having the same path ID, and transmits the actual delay amount included in the acquired delay information to the extracted other delay control devices (1A) as delay information.

[0097] In this way, the delay control system 1000A can automatically adjust the delay of each path that should be adjusted as the same delay to the maximum delay amount of each path by periodically executing the processes of the delay sharing phase and the delay adjustment phase by each delay control device 1. Therefore, even if the path or topology in the network is changed, it is possible to automatically set the delay amount of the path without any operation by an operator.

[0098] The present invention is not limited to the above-described embodiments, and many modifications can be made by a person having ordinary skill in the art within the technical concept of the present invention.

[0099] 1, 1A, 3, 3A Delay control device 4 Delay adjustment device 10, 40 Control unit 11, 41 Input / output unit 12, 42 Storage unit 20 User system 21 Input / output device 22 Input / output management device 30 Central computer system 31 Central computer 100 Delay amount storage unit 110, 110A Delay amount measurement unit 120, 120A Delay sharing unit 130 Delay adjustment unit 400 Path ID information 410 Delay information acquisition unit 420 Delay adjustment unit 1000, 1000A Delay control system

Claims

1. A delay control system that controls delays of multiple paths established between a central computer system and each of multiple user systems, comprising a delay control device for each of the multiple paths, on at least one of the central computer system side or the user system side that is the transmission / reception destination of the multiple paths, that controls the delay of the path, and each delay control device comprises: a delay amount storage unit that stores the maximum delay amount between the central computer system and the user system; a delay amount measurement unit that measures the delay amount between the user system on which it resides and the central computer system as an actual delay amount; a delay sharing unit that repeats a delay sharing phase, which is a process of notifying delay information including the actual delay amount to delay control devices other than itself, acquiring delay information including the actual delay amount from the other delay control devices, and updating the maximum delay amount with the actual delay amount if the actual delay amount is greater than the maximum delay amount stored in the delay amount storage unit, for each predetermined first period; and a delay adjustment unit that repeats a delay adjustment phase, which is a process of adjusting the delay amount between the user system on which it resides and the central computer system so that it becomes the maximum delay amount stored in the delay amount storage unit, for each predetermined second period. A delay control system characterized by:

2. The delay control system of claim 1, characterized in that the same path ID is assigned to paths among the multiple paths that should be adjusted to have the same delay, and the delay sharing unit notifies other delay control devices other than itself of the delay information including the path ID of the path measured by the delay amount measurement unit, and when delay information is received from another delay control device, if the path ID of the path set between the user system on which itself is equipped and the central computer system is the same as the path ID attached to the received delay information, it determines whether the actual delay amount attached to the delay information is greater than the maximum delay amount stored in the delay amount storage unit.

3. A delay control system comprising a central computer system and a delay adjustment device for adjusting delays of multiple paths set between said central computer system and each of multiple user systems, wherein at least one of the central computer system side or the user system side, which is the transmission / reception destination of said multiple paths, is provided for each of said paths, controlling the delay of said path, and said delay adjustment device has path ID information stored in a memory unit for each of said multiple paths, which is information that the same path ID is assigned to paths that should be adjusted to have the same delay, and each of said delay control devices has: a delay amount storage unit for storing the maximum delay amount between said central computer system and said user system; and a delay amount measurement unit for measuring the delay amount between the user system to which it belongs and said central computer system as an actual delay amount. a delay sharing unit that notifies the delay adjustment device of delay information including the actual delay amount and the path ID of the path measured by the delay amount measurement unit, and acquires from the delay adjustment device delay information including the actual delay amount of other paths assigned the same path ID as the path ID of the path set between the user system on which the delay adjustment device is provided and the central computer system, and if the actual delay amount is greater than the maximum delay amount stored in the delay amount storage unit, repeats a delay sharing phase, which is a process of updating the maximum delay amount with the actual delay amount, for every predetermined first period; and a delay adjustment unit that repeats a delay adjustment phase, which is a process of adjusting the delay amount between the user system on which the delay adjustment device is provided and the central computer system so that it becomes the maximum delay amount stored in the delay amount storage unit, for every predetermined second period; A delay control system characterized by comprising a delay adjustment unit that refers to the path ID information, extracts other delay control devices that measure the delay amount of paths with the same path ID as the path ID included in the delay information, and transmits the actual delay amount included in the acquired delay information as delay information to the other extracted delay control devices.

4. A delay control method for a delay control system that controls delays of multiple paths established between a central computer system and each of multiple user systems, wherein the delay control system is provided with a delay control device for each of the multiple paths, at least on the central computer system side or the user system side, which are destinations of transmission and reception of the multiple paths, that controls the delay of the path, and each of the delay control devices has a delay amount storage unit in a memory unit in which the maximum delay amount between the central computer system and the user system is stored, and a step of measuring the delay amount between the user system on which it is provided and the central computer system as an actual delay amount; a step of notifying delay information including the actual delay amount to delay control devices other than itself, acquiring delay information including the actual delay amount from the other delay control devices, and if the actual delay amount is greater than the maximum delay amount stored in the delay amount storage unit, repeating a delay sharing phase, which is a process of updating the maximum delay amount with the actual delay amount, at every predetermined first period; a step of repeating a delay adjustment phase, which is a process of adjusting the delay amount between the user system and the central computer system to be the maximum delay amount stored in the delay amount storage unit, at every predetermined second period.

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