Control Device and Priority Control Method

Abstract

The present invention is a control device in a communication system in which one-way communication and two-way communication are mixed, the control device comprising: a request delay acquisition unit that acquires information on a request delay and information on a degree of priority in traffic for each instance of traffic on the basis of cooperation information that is obtained according to traffic transmitted from multiple wireless terminals and that indicates the communication status between multiple wireless terminals and a base station that performs wireless communication; a traffic-specific congestion calculation unit that calculates a congestion delay in a wired section on the basis of the information on the request delay and information on the degree of priority acquired by the request delay acquisition unit for each instance of traffic; and a priority degree change control unit that, on the basis of the congestion delay in the wired section calculated by the traffic-specific congestion calculation unit, transmits a control signal including at least an instruction to change the degree of priority in traffic of two-way communication to a relay device that relays traffic, so that one-way communication traffic is transmitted with priority when congestion occurs or total delay requirements are not met.　

Description

[Technical Field]

[0001] The present invention relates to a control device and a priority control method. [Background technology]

[0002] Conventional communication control using priority assignment to achieve low latency communication controls one-way communication according to the latency requirements and traffic volume. In the future, it is expected that use cases of round-trip communication, such as remote control in real time based on video, will increase. When performing real-time remote control based on video, the latency requirement for the round-trip from sending the video to reflecting the control will become the latency requirement for the application. [Prior art documents] [Non-patent literature]

[0003] [Non-Patent Document 1] Chao Zhou, “Deadline and Priority-aware Congestion Control for Delay-sensitive Multimedia Streaming”, MM '21, October 20-24, 2021. [Non-patent document 2] Bowen Bao, “TDTS: Three-Dimensional Traffic Scheduling in Optical Fronthaul Networks with Conv-LSTM”, Photonics 2021. [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-14112 Summary of the Invention [Problem to be solved by the invention]

[0005] In a system where unidirectional communication and round-trip communication coexist, if control is performed based on the delay requirements for all unidirectional communication as in the prior art, control may be performed even in cases where it is not necessary to perform control based on priority (for example, network path switching, etc.) when considering round-trip communication. As a result, it may not be possible to achieve highly accurate communication control based on the required quality.

[0006] In view of the above circumstances, an object of the present invention is to provide a technology capable of achieving highly accurate communication control based on the required quality in a system where unidirectional communication and round-trip communication coexist.

Means for Solving the Problem

[0007] One aspect of the present invention is a control device in a communication system where unidirectional communication and round-trip communication coexist, comprising: a request delay acquisition unit that acquires, for each traffic, information on the required delay and information on the priority in the traffic based on cooperation information indicating a communication state between a base station that performs wireless communication with the plurality of wireless terminals and the plurality of wireless terminals, the cooperation information being obtained from the traffic transmitted from the plurality of wireless terminals; a traffic-specific congestion calculation unit that calculates a congestion delay in a wired section based on the information on the required delay acquired for each traffic by the request delay acquisition unit and the information on the priority; and a priority change control unit that transmits a control signal including an instruction to change the priority of the unidirectional communication traffic or the priority of the round-trip communication traffic so that the unidirectional communication traffic is preferentially transmitted when congestion occurs or when the total delay requirement is not satisfied, based on the congestion delay in the wired section calculated by the traffic-specific congestion calculation unit, to a relay device that relays the traffic.

[0008] One aspect of the present invention is a priority control method performed by a control device in a communication system in which unidirectional communication and reciprocal communication coexist. Based on cooperation information indicating a communication state between a base station that performs wireless communication with a plurality of wireless terminals, obtained from traffic transmitted from the plurality of wireless terminals, information on a required delay and information on a priority in the traffic are acquired for each traffic. Based on the information on the required delay acquired for each traffic and the information on the priority, a congestion delay in a wired section is calculated. Based on the calculated congestion delay in the wired section, when congestion occurs or the total delay requirement is not satisfied, a control signal including an instruction to change the priority of unidirectional communication traffic or the priority of reciprocal communication traffic is transmitted to a relay device that relays the traffic so that the unidirectional communication traffic is preferentially transmitted.

Advantages of the Invention

[0009] According to the present invention, in a system in which unidirectional communication and reciprocal communication coexist, it becomes possible to realize highly accurate communication control based on required quality.

Brief Description of the Drawings

[0010]

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Embodiments for Carrying Out the Invention

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. (Overall Configuration) FIG. 1 is a diagram for explaining the overall configuration of the mobile NW system 100 in the present invention. First, the overall configuration of the mobile NW system 100 will be described. The mobile NW system 100 is, for example, a fifth-generation mobile communication system (hereinafter referred to as "5G"). The mobile NW system 100 is an example of a communication system. The mobile NW system 100 includes one or more base stations 10, a plurality of Ph-GWs 20, a server 30, and a control device 40. In the example shown in FIG. 1, the case where there is one base station 10 and two Ph-GWs 20 is shown. Hereinafter, the direction from the base station 10 to the server 30 is defined as the upstream direction, and the direction from the server 30 to the base station 10 is defined as the downstream direction.

[0012] The base station 10 and the Ph-GW 20-1, between the Ph-GW 20-1 and the Ph-GW 20-2, and between the Ph-GW 20-2 and the server 30 are connected by optical fibers that transmit optical signals. The base station 10 and the control device 40, and between the Ph-GW 20 and the control device 40 are connected by electric wires or optical fibers that transmit electric signals.

[0013] The base station 10 includes one or more antennas and performs wireless communication with the wireless terminal 45. For example, each base station 10 receives a signal indicating the traffic demand amount or actual traffic from the wireless terminal 45. The actual traffic is a signal destined for the server 30. The traffic transmitted from the wireless terminal 45 is one-way traffic or round-trip traffic. Here, the one-way traffic is, for example, traffic transmitted from the wireless terminal 60 to the server 30 that does not require a response. The round-trip traffic is, for example, traffic transmitted from the wireless terminal 60 to the server 30 that requires a response to that traffic. The base station 10 is, for example, a DU (Distributed Unit) in the 5G communication standard. The base station 10 acquires cooperation information based on a signal indicating the traffic demand amount.

[0014] The cooperation information is information indicating the communication state between each base station 10 and the wireless terminal 45. The cooperation information includes, for example, radio quality information. The cooperation information includes, for example, traffic allocation information. The cooperation information includes, for example, information regarding delay. The radio quality information is, for example, 5QI (5 QoS Identifier) in the 5G communication standard. The traffic allocation information is the Transport Block Size (TBS) and Buffer Status Report (BSR) for each logical channel.

[0015] Ph-GW20 is a relay device equipped with an optical switch. Ph-GW20 changes the priority of the traffic transmitted from the wireless terminal 45 according to an instruction from the control device 40. Specifically, Ph-GW20 changes the priority of the round-trip traffic. For example, Ph-GW20 does not change the priority of the one-way traffic, but changes the priority of the round-trip traffic so that the priority of the round-trip traffic is lower than that of the one-way traffic.

[0016] The server 30 receives the traffic transmitted from the wireless terminal 60. When the received traffic is round-trip traffic, the server 30 provides a response corresponding to the traffic transmitted from the wireless terminal 45 to the wireless terminal 45. The server 30 is a higher-level device.

[0017] The control device 40 acquires the cooperation information from the base station 10. Based on the acquired cooperation information, the control device 40 instructs Ph-GW20 to change the traffic priority so that the one-way traffic is preferentially transmitted. Specifically, the control device 40 instructs to change the priority of the round-trip traffic. For example, the control device 40 does not change the priority of the one-way traffic, but instructs to change the priority of the round-trip traffic so that the priority of the round-trip traffic is lower than that of the one-way traffic.

[0018] The wireless terminal 45 transmits traffic. The traffic transmitted by the wireless terminal 45 is either a signal indicating the required amount of traffic or actual traffic that is transmission data addressed to the server 30. The wireless terminal 45 performs two-way communication or one-way communication. One-way communication is communication in only the uplink or downlink direction. Two-way communication is communication in both the uplink and downlink directions.

[0019] The core network 50 is, for example, an optical network.

[0020] (First Embodiment) In the first embodiment, in a situation where two-way communication and one-way communication coexist, when one-way communication becomes congested, the priority of two-way communication is lowered to reduce the congestion of one-way communication, and control is performed to meet the delay requirement.

[0021] FIG. 2 is a diagram showing a configuration example of each device in the mobile NW system 100 in the first embodiment. FIG. 2 shows the base station 10, the Ph-GW 20, the server 30, the control device 40, and the wireless terminal 45. Here, the specific configurations of the base station 10, the Ph-GW 20, the control device 40, and the wireless terminal 45 will be described.

[0022] The wireless terminal 45 includes a flag generation unit 46. The flag generation unit 46 generates a flag for identifying whether the communication performed by the wireless terminal 45 is one-way communication or two-way communication. For example, the flag generation unit 46 generates a flag of "0" for one-way communication and a flag of "1" for two-way communication. When transmitting a signal indicating the required amount of traffic or actual traffic, the wireless terminal 45 attaches the flag generated by the flag generation unit 46 to the signal.

[0023] The base station 10 includes an information acquisition unit 11. The information acquisition unit 11 acquires radio quality information, traffic allocation information, and flag information from a signal indicating the required amount of traffic transmitted from the wireless terminal 45. The information acquisition unit 11 transmits the acquired radio quality information, traffic allocation information, and flag information to the control device 40 as cooperation information. In addition, when the base station 10 receives actual traffic from the wireless terminal 45, it transmits the received signal to the Ph-GW20-1.

[0024] The control device 40 includes a request delay calculation unit 41, a traffic congestion calculation unit 42 for each traffic type, and a priority change calculation unit 43. The request delay calculation unit 41 calculates the request delay and the priority of the traffic for each traffic type based on the radio quality information transmitted from the base station 10.

[0025] The traffic congestion calculation unit 42 for each traffic type rearranges the signals transmitted from each wireless terminal 45 according to the priority of the traffic calculated by the request delay calculation unit 41, and calculates the congestion delay based on the bandwidth of the wired section acquired in advance.

[0026] When congestion delay occurs in one-way communication based on the congestion delay obtained by the traffic congestion calculation unit 42 for each traffic type, the priority change calculation unit 43 instructs the Ph-GW20-1 to change the priority of the traffic. Specifically, the priority change calculation unit 43 instructs not to change the priority of one-way communication but to lower the priority of round-trip communication. At this time, the priority change calculation unit 43 divides the priority into two levels: "high" and "low". For example, when the priority is 5, the priority change calculation unit 43 makes it distinguishable within the same priority, such as 5-1 and 5-0. The priority indicating a high priority for one-way communication with the same priority where congestion occurs is set as (5-1), and the priority indicating a low priority for round-trip communication with the same priority is set as (5-0). The priority change calculation unit 43 generates a control signal including the instruction and transmits it to the Ph-GW20-1. The priority change calculation unit 43 is an example of a priority change control unit.

[0027] Ph-GW20-1 includes a priority change unit 21. The priority change unit 21 changes the priority of the specified traffic according to the control signal transmitted from the control device 40. For example, the priority change unit 21 lowers the priority of the specified traffic according to the control signal transmitted from the control device 40. The value of the priority to be lowered may be 1 or more. Thereby, in Ph-GW20-1, when the specified signal (round-trip communication signal) is obtained from the base station 10, the priority is lowered. As a result, the one-way communication signal will be preferentially transmitted.

[0028] FIG. 3 is a diagram showing a configuration example of the request delay calculation unit 41 in the first embodiment. The request delay calculation unit 41 includes a radio quality information collection unit 411, a request delay calculation unit 412, a traffic priority calculation unit 413, a traffic allocation information collection unit 414, and a traffic volume calculation unit 415.

[0029] The radio quality information collection unit 411 collects the radio quality information included in the cooperation information transmitted from each base station 10. The radio quality information collection unit 411 outputs the collected radio quality information to the request delay calculation unit 412.

[0030] The request delay calculation unit 412 calculates the request delay by checking the mapping based on the radio quality information included in the cooperation information transmitted from each base station 10.

[0031] The traffic priority calculation unit 413 determines the priority of the traffic by checking the mapping based on the radio quality information included in the cooperation information transmitted from each base station 10.

[0032] The traffic allocation information collection unit 414 collects the traffic allocation information (TBS or BSR) included in the cooperation information transmitted from each base station 10. The traffic allocation information collection unit 414 outputs the collected traffic allocation information to the traffic volume calculation unit 415.

[0033] The traffic volume calculation unit 415 determines the traffic volume based on the traffic allocation information output from the traffic allocation information collection unit 414. Note that the traffic volume calculation unit 415 may determine the value (the value of TBS or BSR) indicated by the traffic allocation information as the traffic volume. The traffic volume calculation unit 415 may also determine, as the traffic volume, a value obtained by adding an overhead to the value indicated by the traffic allocation information.

[0034] FIG. 4 is a diagram showing a configuration example of the traffic-specific congestion calculation unit 42 in the first embodiment. The traffic-specific congestion calculation unit 42 includes a traffic priority sorting unit 421 and a priority-based congestion delay calculation unit 422.

[0035] The traffic priority sorting unit 421 receives the traffic priority information determined by the traffic priority calculation unit 413 and the traffic volume information determined by the traffic volume calculation unit 415. The traffic priority sorting unit 421 sorts the traffic in order from the highest priority based on the input traffic priority information and traffic volume information.

[0036] The priority-based congestion delay calculation unit 422 calculates the congestion delay in order from the highest priority, using the traffic volume, link rate, and queuing volume. Thereby, the priority-based congestion delay calculation unit 422 calculates the traffic congestion delay for each priority. The calculation granularity is performed at intervals shorter than the required delay from the perspective of calculation time. It may be calculated at the transmission interval of the traffic in the radio section. Whether the calculation period is made independent or shared, it is implemented so as to satisfy those with strict required delays.

[0037] When the required delay varies depending on the priority, in order to reduce the computational load, traffic with a higher priority than the priority with a smaller required delay makes a determination according to the smaller required delay. For example, when the priority "high" has a required delay of 10 ms, the priority "medium" has a required delay of 5 ms, and the priority "low" has a required delay of 10 ms, the convergence delay calculation unit 422 for each priority calculates the convergence delay at intervals shorter than 5 ms for the priorities "high" and "medium", and executes the calculation of the convergence delay at intervals shorter than 10 ms for the priority "low". The convergence delay calculation unit 422 for each priority executes it in units of packets or bursts. (Calculation in units of 1 us and 5 ms), the computational load decreases when the calculation interval is widened. Considering the timing difference in the period of burst traffic, if the length is different for the uplink and downlink by about half of the required delay, it may be mechanically in units of 1 ms.

[0038] FIG. 5 is a diagram for explaining the process of calculating the convergence delay for each priority by the traffic-specific convergence calculation unit 42 in the first embodiment. As shown in FIG. 4, it is assumed that traffic amounts of 500 kbit (priority = 6), 500 kbit (priority = 7), and 300 kbit (priority = 8) are input to the traffic-specific convergence calculation unit 42. The traffic priority sorting unit 421 first sorts the input traffic in descending order of priority. Here, the traffic priority sorting unit 421 sets the traffic amount of 300 kbit (priority = 8) with the highest priority as the priority "high", then sets the traffic amount of 500 kbit (priority = 7) with the next highest priority as the priority "medium", and sorts the traffic amount of 500 kbit (priority = 6) with the lowest priority as the priority "low".

[0039] The congestion delay calculation unit 422 by priority assigns traffic in order from the highest priority. Here, assume that the required delay for each traffic is 5 ms and the link rate is 5 Mbit. The traffic with the priority of "high" is 1.5 Mbit (300 kbit × 5 ms) of traffic with respect to the link rate of 5 Mbit. Therefore, it can be transmitted without congestion. The traffic with the priority of "medium" is 2.5 Mbit (500 kbit × 5 ms) of traffic with respect to the link rate of 5 Mbit - 1.5 Mbit = 3.5 Mbit. Therefore, it can be transmitted without congestion. On the other hand, the traffic with the priority of "low" is 2.5 Mbit (500 kbit × 5 ms) of traffic with respect to the link rate of 5 Mbit - 1.5 Mbit - 2.5 Mbit = 1 Mbit. In this case, congestion of 1.5 Mbit occurs. Considering that this congestion traffic is processed at 200 Mbps (1 Mbit / 5 ms), the congestion delay calculation unit 422 by priority calculates a congestion delay of 1.5 / 200 = 7.5 ms.

[0040] Figure 6 is a flowchart showing the processing flow of the control device 40 in the first embodiment. The required delay calculation unit 41 collects the cooperation information transmitted from each base station 10 (step S101). The required delay calculation unit 412 calculates the required delay for each traffic based on the radio quality information included in the cooperation information transmitted from each base station 10 (step S102). The traffic priority calculation unit 413 determines the priority for each traffic based on the radio quality information included in the cooperation information transmitted from each base station 10 (step S103). The traffic priority calculation unit 413 outputs the priority information for each determined traffic to the traffic-by-traffic congestion calculation unit 42.

[0041] The traffic volume calculation unit 415 determines the traffic volume for each traffic based on the traffic allocation information included in the cooperation information transmitted from each base station 10 (step S104). The traffic volume calculation unit 415 outputs the information on the traffic volume for each determined traffic to the traffic-specific congestion calculation unit 42. The traffic-specific congestion calculation unit 42 calculates the congestion delay based on the priority information for each traffic output from the traffic priority calculation unit 413 and the traffic volume information for each traffic output from the traffic volume calculation unit 415 (step S105). The traffic-specific congestion calculation unit 42 outputs the calculated congestion delay information to the priority change calculation unit 43.

[0042] The priority change calculation unit 43 determines whether a congestion delay has occurred based on the congestion delay information output from the traffic-specific congestion calculation unit 42 (step S106). For example, when the congestion delay in the congestion delay information is other than 0, the priority change calculation unit 43 determines that a congestion delay has occurred. On the other hand, when the congestion delay in the congestion delay information is 0, the priority change calculation unit 43 determines that no congestion delay has occurred.

[0043] When the priority change calculation unit 43 determines that no congestion delay has occurred (step S106-NO), the control device 40 ends the process. When the priority change calculation unit 43 determines that a congestion delay has occurred (step S106-YES), the priority change calculation unit 43 instructs the Ph-GW 20-1 to change the priority of the round-trip communication (step S107). Specifically, the priority change calculation unit 43 generates a control signal including an instruction to lower the priority of the round-trip communication. The priority change calculation unit 43 transmits the generated control signal to the Ph-GW 20-1.

[0044] FIG. 7 is a sequence diagram showing the processing flow of the mobile NW system 100 in the first embodiment. Here, in the description of FIG. 7, it is assumed that the wireless terminal 45-1 is connected to the base station 10-1 and the wireless terminal 45-2 is connected to the base station 10-2.

[0045] The flag generation unit 46 of the wireless terminal 45-1 generates a flag indicating one-way communication (step S201). The wireless terminal 45-1 adds the generated flag to the traffic (for example, a signal indicating the required amount of traffic) and transmits it to the base station 10-1 (step S202). The base station 10-1 receives the traffic transmitted from the wireless terminal 45-1. The information acquisition unit 11 of the base station 10-1 acquires the radio quality information, the traffic allocation information, and the flag information from the received traffic. The information acquisition unit 11 of the base station 10-1 transmits the acquired radio quality information, the traffic allocation information, and the flag information (for example, "0" indicating one-way communication) to the control device 40 as cooperation information (step S203).

[0046] The flag generation unit 46 of the wireless terminal 45-2 generates a flag indicating two-way communication (step S204). The wireless terminal 45-2 adds the generated flag to the traffic (for example, a signal indicating the required amount of traffic) and transmits it to the base station 10-2 (step S205). The base station 10-2 receives the traffic transmitted from the wireless terminal 45-2. The information acquisition unit 11 of the base station 10-2 acquires the radio quality information, the traffic allocation information, and the flag information from the received traffic. The information acquisition unit 11 of the base station 10-2 transmits the acquired radio quality information, the traffic allocation information, and the flag information (for example, "1" indicating two-way communication) to the control device 40 as cooperation information (step S206).

[0047] The control device 40 collects the cooperation information transmitted from each of the base stations 10-`1 and 10-2. The control device 40 executes processing based on the collected cooperation information based on the cooperation information (step S207). Here, the processing based on the cooperation information is, for example, the processing from step S102 to step S105 in FIG. 6. The control device 40 determines whether or not congestion has occurred based on the calculated congestion delay (step S208). Here, it is assumed that congestion has occurred.

[0048] The control device 40 instructs Ph-GW20-1 to change the priority of the round-trip communication. Specifically, the control device 40 generates a control signal including an instruction to lower the priority of the round-trip communication. The control device 40 transmits the generated control signal to Ph-GW20-1 (step S209).

[0049] The priority change unit 21 of Ph-GW20-1 changes the priority of the traffic of the target round-trip communication according to the control signal transmitted from the control device 40 (step S210). Specifically, when the traffic of the target round-trip communication is received from the base station 10, the priority change unit 21 of Ph-GW20-1 lowers the priority of the received round-trip communication traffic. As a result, when there is a plurality of traffics, Ph-GW20-1 preferentially transmits the traffic of the one-way communication in the upward direction. Whether the traffic transmitted from the base station 10 is the traffic of the target round-trip communication may be determined based on a flag.

[0050] Next, specific processing in the first embodiment will be described using a specific example. <Input flow> (Upward direction: Link 1 Gbps, Transmission delay 0.8 ms) One-way communication: 200 kbit (One-way / Priority 5 / Required delay 1 ms) Round-trip communication (1): 500 kbit (One-way / Priority 5 / Required delay 1 ms - Round-trip 2 ms) Round-trip communication (2): 600 kbit (One-way / Priority 5 / Required delay 1 ms - Round-trip 2 ms) (Downward direction: Link 1 Gbps, Transmission delay 0.8 ms) Round-trip communication (1): 100 Mbps (One-way / Priority 5 / Required delay 1 ms - Round-trip 2 ms) Round-trip communication (2): 100 Mbps (One-way / Priority 5 / Required delay 1 ms - Round-trip 2 ms) Let it be so.

[0051] In the prior art, congestion occurs in the upstream communication with a delay of 0.3 ms, resulting in a one-way communication delay of 1.1 ms, which does not meet the delay requirement. Therefore, it is necessary to reduce the upstream traffic transmission volume or distribute the traffic of another path. However, since the downstream communication has a margin for the required delay, when congestion occurs, changing the priority may meet the total delay requirement. Therefore, as shown in the first embodiment, if the priority is subdivided, the priority for one-way communication is set to (5-1), and the priority for round-trip communication is lowered (5-2), the following will occur.

[0052] (Upstream direction: Link 1 Gbps, transmission delay 0.8 ms) One-way communication: 200 kbit (one-way / priority 5-1 / required delay 1 ms) Round-trip communication (1): 500 kbit (one-way / priority 5-2 / required delay 1 ms - round-trip 2 ms) Round-trip communication (2): 600 kbit (one-way / priority 5-2 / required delay 1 ms - round-trip 2 ms)

[0053] (Downstream direction: Link 1 Gbps, transmission delay 0.8 ms) Round-trip communication (1): 100 Mbps (one-way / priority 5-2 / required delay 1 ms - round-trip 2 ms) Round-trip communication (2): 100 Mbps (one-way / priority 5-2 / required delay 1 ms - round-trip 2 ms), and it can be seen that the one-way communication has a delay of 0.8 ms and the round-trip communication has a maximum round-trip delay of 1.98 ms, meeting the delay requirement.

[0054] According to the mobile NW system 100 configured as described above, the control device 40 includes a required delay calculation unit 41 that acquires information on required delay and priority information in traffic for each traffic based on the cooperation information obtained from each base station 10, a traffic-specific congestion calculation unit 42 that calculates the congestion delay in the wired section based on the required delay information and priority information acquired for each traffic, and a priority change calculation unit 43 that transmits a control signal including an instruction to change the priority of the traffic of the round-trip communication so that the traffic of the one-way communication is preferentially transmitted when congestion occurs based on the congestion delay in the wired section, to the Ph-GW 20-1. As a result, for traffic that did not satisfy the total (end-to-end in the case of one-way, round-trip in the case of round-trip communication) delay requirement in the conventional case, it is possible to perform communication that satisfies the delay requirement by lowering the priority for round-trip communication. Therefore, in the mobile NW system 100 in which one-way communication and round-trip communication coexist, it is possible to realize highly accurate communication control based on the required quality.

[0055] (Modification Example 1 in the First Embodiment) In the above-described configuration, a configuration in which the Ph-GW 20 and the control device 40 determine whether the traffic is round-trip communication traffic or one-way communication traffic based on a flag added to the traffic is shown. In contrast, the Ph-GW 20 and the control device 40 may be configured to determine whether the traffic is round-trip communication traffic or one-way communication traffic based on information in the radio section such as NSSAI, DCN, ID, QoS flow ID, Bearer ID, PDU session ID, and DRB ID.

[0056] FIG. 8 is a diagram showing a configuration example of each device in the mobile NW system 100a in Modification Example 1 of the first embodiment. In the example shown in FIG. 8, compared with FIG. 2, the wireless terminal 45a is not provided with the flag generation unit 46. Further, the control device 40a is provided with a priority change calculation unit 43a instead of the priority change calculation unit 43.

[0057] The priority change calculation unit 43a determines a target radio section ID and a priority to be changed based on the information of the radio section. The target radio section ID is information for identifying a radio section that is a target of priority change among radio sections. Then, the priority change calculation unit 43a generates a control signal including the target radio section ID and the priority to be changed. The priority change calculation unit 43a transmits the generated control signal to the Ph-GW20-1. The priority change unit 21 of the Ph-GW20-1 changes the priority of the specified traffic according to the control signal transmitted from the control device 40a. For example, the priority change unit 21 lowers the priority of the specified traffic according to the control signal transmitted from the control device 40a. The priority change unit 21 makes a determination based on the information of the radio section obtained in the section indicated by the target radio section ID for the specified traffic.

[0058] (Modification Example 2 in the First Embodiment) In the above-described embodiment, the control device 40 is configured to instruct the Ph-GW20 not to change the priority of one-way traffic but to lower the priority of round-trip traffic so that one-way traffic is preferentially transmitted. The control device 40 may give other instructions as long as it can change the priority of traffic so that one-way traffic is preferentially transmitted. For example, the control device 40 may instruct the Ph-GW20 not to change the priority of round-trip traffic but to raise the priority of one-way traffic above the priority of round-trip traffic, or may instruct to raise the priority of one-way traffic above the priority of round-trip traffic and lower the priority of round-trip traffic below the priority of one-way traffic.

[0059] (Second Embodiment) In the second embodiment, in a situation where round-trip communication and one-way communication coexist, when one-way communication becomes congested, the configuration for controlling to maintain the quality of traffic of one-way communication by lowering the priority of the upstream direction of round-trip communication and raising the priority of the downstream direction of round-trip communication will be described.

[0060] FIG. 9 is a diagram showing a configuration example of each device in the mobile NW system 100b in the second embodiment. FIG. 9 shows a base station 10, a Ph-GW 20b, a server 30b, a control device 40, and a wireless terminal 45. Here, the specific configurations of the Ph-GW 20b and the server 30b will be described. Note that the configurations and processes of the base station 10, the control device 40, and the wireless terminal 45 are the same as those in the first embodiment.

[0061] Ph-GW 20b-1 changes the priority and the flag for the traffic of the uplink round-trip communication. Ph-GW 20b-1 includes a priority change unit 21-1 and a flag change unit 22-1. The priority change unit 21-1 changes the priority of the specified uplink round-trip communication traffic according to the control signal transmitted from the control device 40. The flag change unit 22-1 changes the flag of the uplink round-trip communication traffic in order to increase the priority of the downlink round-trip communication traffic. For example, the flag change unit 22-1 changes the flag of the uplink round-trip communication traffic from "1" indicating round-trip communication to "2" indicating an increase in priority in the downlink direction.

[0062] Ph-GW 20b-2 changes the priority and the flag for the traffic of the downlink round-trip communication. Ph-GW 20b-2 includes a priority change unit 21-2 and a flag change unit 22-2. When the flag added to the traffic acquired from the server 30b is a flag for increasing the priority (for example, "2" indicating an increase in priority), the flag change unit 22-2 changes the flag of the traffic acquired from the server 30b from "2" indicating an increase in priority to "1" indicating round-trip communication.

[0063] When the flag added to the traffic acquired from the server 30b is a flag for increasing the priority (for example, "2" indicating an increase in priority), the priority change unit 21-2 changes the priority of the traffic acquired from the server 30b. For example, the priority change unit 21-2 raises the priority of the traffic acquired from the server 30b by one level (for example, priority 5-1 → 5-2). Note that when changing the priority, the priority change unit 21-2 may perform priority subdivision as in the first embodiment, or may be based on the normal priority (for example, priority 5 → 6).

[0064] The server 30b receives and processes the upstream traffic. The server 30b includes a flag generation unit 31. When it is necessary to transmit downstream traffic, the flag generation unit 31 generates a flag to be added to the downstream traffic and adds the flag to the downstream traffic. For example, the flag generation unit 31 assigns the flag acquired from the upstream traffic. The case where it is necessary to transmit downstream traffic is, for example, when upstream traffic from the wireless terminal 45 is obtained.

[0065] According to the mobile NW system 100b configured as described above, the same effects as those of the first embodiment can be obtained. In the mobile NW system 100a, in the Ph-GW 20, the flag and the priority are changed so as to lower the priority of the upstream traffic and raise the priority of the downstream traffic. Thereby, the quality of the traffic of the one-way communication can be maintained. As a result, in the mobile NW system 100a in which one-way communication and round-trip communication coexist, it becomes possible to realize highly accurate communication control based on the required quality.

[0066] (Modification Example 1 in the Second Embodiment) In the above-described configuration, Ph-GW20b and the control device 40 are configured to determine whether the traffic is two-way communication traffic or one-way communication traffic based on the flag added to the traffic. In contrast, Ph-GW20b and the control device 40 may be configured to determine whether the traffic is two-way communication traffic or one-way communication traffic based on information in the radio section such as NSSAI, DCN, ID, QoS flow ID, Bearer ID, PDU session ID, and DRB ID.

[0067] FIG. 10 is a diagram showing a configuration example of each device in the mobile NW system 100c in Modification 1 of the second embodiment. In the example shown in FIG. 10, compared with FIG. 9, the flag change unit 22-1 is not provided in Ph-GW20c-1, the flag change unit 22-2 is not provided in Ph-GW20c-2, and the flag generation unit 46 is not provided in the wireless terminal 45c. Further, the control device 40c is provided with a priority change calculation unit 43c instead of the priority change calculation unit 43.

[0068] The priority change calculation unit 43c determines the target radio section ID and the priority to be changed based on the information in the radio section. Then, the priority change calculation unit 43c generates a control signal including the target radio section ID and the priority to be changed. The priority change calculation unit 43c transmits the generated control signal to all of Ph-GW20c-1 and 20c-2. For example, the control device 40c determines the current communication based on the target radio section ID of the traffic, and transmits an instruction to lower the priority for the uplink traffic and raise the priority for the downlink traffic.

[0069] (Modification 2 in the second embodiment) In the above-described embodiment, the control device 40 is configured to instruct the Ph-GW20b to lower the priority of the uplink direction of the two-way communication and raise the priority of the downlink direction of the two-way communication so that one-way traffic is preferentially transmitted. The control device 40 may give other instructions as long as it can change the priority of the traffic so that one-way traffic is preferentially transmitted. For example, the control device 40 may instruct the Ph-GW20b not to change the priority of the traffic in the uplink direction of the round-trip and to raise the priority of the one-way traffic above the priority of the traffic in the uplink direction of the round-trip, or may instruct to raise the priority of the one-way traffic above the priority of the traffic in the uplink direction of the round-trip and lower the priority of the traffic in the uplink direction of the round-trip below the priority of the one-way traffic.

[0070] (Third Embodiment) In the third embodiment, in a situation where two-way communication and one-way communication coexist, when the one-way communication does not satisfy the delay requirement, a configuration for controlling to meet the required delay of the total communication by changing the priority of the two-way communication will be described.

[0071] FIG. 11 is a diagram showing a configuration example of each device in the mobile NW system 100d in the third embodiment. FIG. 11 shows a base station 10d, a Ph-GW20d-1, a Ph-GW20b-2, a server 30b, a control device 40d, and a wireless terminal 45. Here, the specific configurations of the base station 10d, the Ph-GW20d-1, and the control device 40d will be described. Note that the configurations and processes of the server 30b, the Ph-GW20b-2, and the wireless terminal 45 are the same as those in the second embodiment.

[0072] The base station 10d performs the same processes as in the first and second embodiments. Further, the information acquisition unit 11 of the base station 10d further acquires delay information of the radio section (the section between the wireless terminal 45 and the base station 10d). The information acquisition unit 11 of the base station 10d transmits the acquired radio quality information, traffic allocation information, flag information, and delay information to the control device 40d as cooperation information.

[0073] Ph-GW20d-1 performs the same processing as in the second embodiment. Further, Ph-GW20d-1 acquires delay information of the wired section. The delay measurement is performed by ping or the like. Ph-GW20d-1 transmits the acquired delay information of the wired section to the control device 40d.

[0074] The control device 40d includes a required delay calculation unit 41, a traffic-specific congestion calculation unit 42, a priority change calculation unit 43d, and a delay determination unit 44. The control device 40d is different in configuration from the control device 40 in that it includes a priority change calculation unit 43d instead of the priority change calculation unit 43 and newly includes a delay determination unit 44. Other configurations of the control device 40d are the same as those of the control device 40. Hereinafter, the priority change calculation unit 43d and the delay determination unit 44 will be described.

[0075] The delay determination unit 44 calculates a delay time based on the delay information of the wired section acquired from Ph-GW20d-1, the delay information of the wireless section acquired from the base station 10d, and the congestion delay. The delay determination unit 44 determines whether the calculated delay time satisfies the required delay. For example, when the delay time is within the required delay, the delay determination unit 44 determines that the delay time satisfies the required delay. On the other hand, when the delay time exceeds the required delay, the delay determination unit 44 determines that the delay time does not satisfy the required delay. Hereinafter, when the delay time satisfies the required delay, it is described that the total delay requirement is satisfied, and when the delay time does not satisfy the required delay, it is described that the total delay requirement is not satisfied.

[0076] Based on the determination result of the delay determination unit 44, the priority change calculation unit 43d instructs Ph-GW20d-1 to change the priority of the traffic when the one-way required delay is not satisfied and the required delay of the round-trip communication is satisfied as a result of changing the priority of the round-trip communication traffic.

[0077] FIG. 12 is a flowchart showing the processing flow of the control device 40d in the third embodiment. The request delay calculation unit 41 collects the cooperation information transmitted from each base station 10d (step S301). The request delay calculation unit 412 calculates the request delay for each traffic based on the radio quality information included in the cooperation information transmitted from each base station 10d (step S302). The traffic priority calculation unit 413 determines the priority for each traffic based on the radio quality information included in the cooperation information transmitted from each base station 10d (step S303). The traffic priority calculation unit 413 outputs the information on the priority for each traffic determined to the traffic-specific congestion calculation unit 42.

[0078] The traffic volume calculation unit 415 determines the traffic volume for each traffic based on the traffic allocation information included in the cooperation information transmitted from each base station 10d (step S304). The traffic volume calculation unit 415 outputs the information on the traffic volume for each traffic determined to the traffic-specific congestion calculation unit 42. The traffic-specific congestion calculation unit 42 calculates the congestion delay based on the information on the priority for each traffic output from the traffic priority calculation unit 413 and the information on the traffic volume for each traffic output from the traffic volume calculation unit 415 (step S305). The traffic-specific congestion calculation unit 42 outputs the information on the calculated congestion delay to the delay determination unit 44.

[0079] The delay determination unit 44 acquires the delay information of the wired section from the Ph-GW 20d-1 (step S306). The delay determination unit 44 calculates the delay time based on the delay information of the wired section acquired from the Ph-GW 20d-1, the delay information of the wireless section included in the cooperation information transmitted from each base station 10d, and the congestion delay (step S307). The delay determination unit 44 outputs the information on the calculated delay time to the priority change calculation unit 43d.

[0080] The priority change calculation unit 43d determines whether the total delay requirement is met by determining whether the calculated delay time meets the required delay (step S308). When the priority change calculation unit 43d determines that the total delay requirement is met (step S308 - YES), the control device 40d ends the process. When the priority change calculation unit 43d determines that the total delay requirement is not met (step S308 - NO), the priority change calculation unit 43d instructs Ph-GW20d-1 to change the priority of the round-trip communication (step S309). Specifically, the priority change calculation unit 43d generates a control signal including an instruction to lower the priority of the round-trip communication. The priority change calculation unit 43d transmits the generated control signal to Ph-GW20d-1.

[0081] Next, a specific example will be used to describe the specific processing in the third embodiment. (Upward direction: Link 1 Gbps, transmission delay 0.8 ms) One-way communication: 200 kbit (one-way / priority 5 / required delay 1 ms) Round-trip communication (1): 500 kbit (one-way / priority 5 / required delay 1 ms - round-trip 2 ms) Round-trip communication (2): 600 kbit (one-way / priority 5 / required delay 1 ms - round-trip 2 ms) (Downward direction: Link 1 Gbps, transmission delay 0.8 ms) Round-trip communication (1): 100 Mbps (one-way / priority 5 / required delay 1 ms - round-trip 2 ms) Round-trip communication (2): 100 Mbps (one-way / priority 5 / required delay 1 ms - round-trip 2 ms) Let it be so.

[0082] In the prior art, convergence occurs in the upstream communication for 0.3 ms, resulting in a one-way communication delay of 1.1 ms, which fails to meet the delay requirement. Therefore, it is necessary to reduce the upstream traffic transmission volume or distribute the traffic of another route. However, when considering the downstream communication and calculating whether the required delay can be met, for round-trip communication, the allowable convergence delay is up to the required delay for round-trip (2 ms) - transmission delay (0.8 ms + 0.8 ms) = 0.4 ms. Even with an upstream communication convergence delay of 0.38 ms, the delay requirement can be met. Therefore, as shown in the third embodiment, the priority for round-trip communication that meets the delay requirement is lowered (priority 5 → 4). As a result, the following occurs.

[0083] (Upstream direction: Link 1 Gbps, transmission delay 0.8 ms) One-way communication: 200 kbit (one-way / priority 5 / required delay 1 ms) Round-trip communication (1): 500 kbit (one-way / priority 4 / required delay 1 ms - round-trip 2 ms) Round-trip communication (2): 600 kbit (one-way / priority 4 / required delay 1 ms - round-trip 2 ms)

[0084] (Downstream direction: Link 1 Gbps, transmission delay 0.8 ms) Round-trip communication (1): 100 Mbps (one-way / priority 5 / required delay 1 ms - round-trip 2 ms) Round-trip communication (2): 100 Mbps (one-way / priority 5 / required delay 1 ms - round-trip 2 ms), and it can be seen that the one-way communication has a delay of 0.8 ms and the round-trip communication has a maximum round-trip delay of 1.98 ms, meeting the delay requirement.

[0085] According to the mobile NW system 100d configured as above, when the traffic of one-way communication fails to meet the delay requirement, the priority of the traffic of round-trip communication is changed to determine whether the total delay requirement is met. And in the mobile NW system 100b, the priority of the traffic of round-trip communication is changed only when changing the priority of the traffic of round-trip communication can meet the total delay requirement. Thereby, unnecessary control can be suppressed.

[0086] (Modification Example 1 in the Third Embodiment) In the above-described configuration, a configuration was shown in which Ph-GW20b-1, 20d-1, and the control device 40d determine whether the traffic is two-way communication traffic or one-way communication traffic based on the flag added to the traffic. In contrast, Ph-GW20b-1, 20d-1, and the control device 40d may be configured to determine whether the traffic is two-way communication traffic or one-way communication traffic based on information in the radio section such as NSSAI, DCN, ID, QoS flow ID, Bearer ID, PDU session ID, and DRB ID.

[0087] FIG. 13 is a diagram showing a configuration example of each device in the mobile NW system 100e in Modification Example 1 of the third embodiment. In the example shown in FIG. 13, compared with FIG. 11, the flag change unit 22-1 is not provided in Ph-GW20e-1, the flag change unit 22-2 is not provided in Ph-GW20e-2, and the flag generation unit 46 is not provided in the wireless terminal 45e. Further, the control device 40e is provided with a priority change calculation unit 43e instead of the priority change calculation unit 43d.

[0088] The priority change calculation unit 43e determines the target radio section ID and the priority to be changed based on the information in the radio section. Then, the priority change calculation unit 43e generates a control signal including the target radio section ID and the priority to be changed. The priority change calculation unit 43e transmits the generated control signal to all of Ph-GW20e-1 and 20e-2. For example, the control device 40e determines the current communication based on the target radio section ID of the traffic, and transmits an instruction to lower the priority for the uplink traffic and raise the priority for the downlink traffic.

[0089] (Modification Example 2 in the Third Embodiment) In the above-described embodiment, the control device 40d is configured to instruct the Ph-GW20d to lower the priority of the two-way communication traffic below that of the one-way traffic so that the one-way traffic is preferentially transmitted. The control device 40d may give other instructions as long as it can change the traffic priority so that the one-way traffic is preferentially transmitted. For example, the control device 40d may instruct the Ph-GW20d not to change the priority of the two-way traffic but to increase the priority of the one-way traffic above that of the two-way traffic, or may instruct to increase the priority of the one-way traffic above that of the two-way traffic and at the same time lower the priority of the two-way traffic below that of the one-way traffic.

[0090] (Fourth Embodiment) In the fourth embodiment, in a situation where two-way communication and one-way communication coexist, when the one-way communication does not meet the delay requirement, a configuration for controlling to meet the required delay of the total communication by changing the priority from the upstream traffic in advance will be described.

[0091] FIG. 14 is a diagram showing a configuration example of each device in the mobile NW system 100f in the fourth embodiment. FIG. 14 shows a base station 10d, a Ph-GW20d-1, a Ph-GW20b-2, a server 30b, a control device 40f, and a wireless terminal 45. Here, the specific configuration of the control device 40f will be described. Note that other configurations and processes are the same as those in the third embodiment.

[0092] The control device 40f includes a required delay calculation unit 41, a traffic-specific congestion calculation unit 42, a priority change calculation unit 43f, and a delay determination unit 44. The control device 40f is different in configuration from the control device 40d in that it includes a priority change calculation unit 43f instead of the priority change calculation unit 43d. Based on the determination result of the delay determination unit 44, when there is a round-trip communication that does not satisfy the delay requirement and the result of changing the priority satisfies the required delay for all communications, the priority change calculation unit 43f instructs the Ph-GW20d-1 to change the priority of the traffic. Specifically, the priority change calculation unit 43f performs a finer division of the priority and divides the priority into two levels: "high" and "low". For example, when the priority is 5, the priority change calculation unit 43f makes it distinguishable within the same priority level, such as 5-1 and 5-0. The priority indicating a high priority for one-way communication with the same priority level where congestion occurs is set as (5-1), and the priority indicating a low priority for round-trip communication with the same priority level is set as (5-0).

[0093] The difference from the control device 40d in the third embodiment is that in the control device 40f, regarding the case where congestion increases in the downlink communication (return path) and the delay requirement is not satisfied, it is determined in advance in the uplink communication (forward path) and controlled to satisfy the delay requirement by increasing the QoS control - priority.

[0094] Next, specific processing in the fourth embodiment will be described using a specific example. (Uplink direction: Link 1Gbps, transmission delay 0.8ms) One-way communication (1): 700 kbit (one-way / priority 5 / required delay 1ms) Round-trip communication (1): 200 kbit (one-way / priority 5 / required delay 1ms - round-trip 2ms) Round-trip communication (2): 200 kbit (one-way / priority 5 / required delay 1ms - round-trip 2ms) (Downlink direction: Link 1Gbps, transmission delay 0.8ms) One-way communication (2): 100 kbit (one-way / priority 5 / required delay 1ms) Round-trip communication (1): 700 kbit (one-way / priority 5 / required delay 1ms - round-trip 2ms) Round-trip communication (2): 600 kbit (one-way / priority 5 / required delay 1 ms - round-trip 2 ms) Let it be so.

[0095] In the prior art, congestion occurs at 0.1 ms in the upstream communication and 0.4 ms in the downstream communication, resulting in a delay of 2.1 ms for the round-trip communication (1), which does not meet the round-trip delay requirement. Therefore, it is necessary to reduce the downstream traffic transmission volume or distribute the traffic of another path. However, when calculating whether to meet the required delay considering the downstream communication during the upstream communication, regarding the round-trip communication, a congestion delay of up to 0.4 ms is acceptable for the round-trip, and a congestion of up to 0.2 ms is acceptable for the one-way communication in the upstream communication. Therefore, by imposing congestion on the one-way communication in the upstream, both the one-way communication and the round-trip communication can meet the delay requirement as the total delay. Therefore, as shown in the fourth embodiment, the priority change calculation unit 43f instructs to increase the priority (priority 5 → 6) for the round-trip communication that meets the delay requirement. Further, the priority change calculation unit 43f instructs to lower the priority of the round-trip communication (priority 5 → 4) so that the delay requirement of the one-way communication is met for the downstream. As a result, the following is obtained.

[0096] (Upstream direction: Link 1 Gbps, transmission delay 0.8 ms) One-way communication (1): 700 kbit (one-way / priority 5 / required delay 1 ms) Round-trip communication (1): 200 kbit (one-way / priority 6 / required delay 1 ms - round-trip 2 ms) Round-trip communication (2): 200 kbit (one-way / priority 6 / required delay 1 ms - round-trip 2 ms)

[0097] (Downstream direction: Link 1 Gbps, transmission delay 0.8 ms) One-way communication (2): 100 kbit (one-way / priority 5 / required delay 1 ms) Round-trip communication (1): 700 kbit (one-way / priority 4 / required delay 1 ms - round-trip 2 ms) The round-trip communication (2) is 600 kbit (one-way / priority 4 / required delay 1 ms - round-trip 2 ms). The one-way communication (1) has a delay of 0.96 ms, the round-trip communication has a round-trip delay of 1.94 ms, and the one-way communication (2) has a delay of 0.8 ms. It can be seen that the delay requirements are met.

[0098] According to the mobile NW system 100f configured as described above, when there is round-trip communication that does not meet the delay requirements, as a result of changing the priority of the round-trip communication traffic, it is determined whether all communications meet the required delay. In the mobile NW system 100f, when all communications meet the required delay, the priority of the round-trip communication traffic is changed. In this way, in the mobile NW system 100f, it is determined in advance whether the required delay is met based on the uplink communication, and control is performed to meet the delay requirements. As a result, in the mobile NW system 100f where one-way communication and round-trip communication are mixed, it becomes possible to realize highly accurate communication control based on the required quality.

[0099] (Modification Example 1 in the Fourth Embodiment) In the above-described configuration, a configuration is shown in which Ph-GW20b-1, 20d-1 and the control device 40f determine whether the traffic is round-trip communication traffic or one-way communication traffic based on the flag added to the traffic. On the other hand, Ph-GW20b-1, 20d-1 and the control device 40f may be configured to determine whether the traffic is round-trip communication traffic or one-way communication traffic based on information in the radio section such as NSSAI, DCN, ID, QoS flow ID, Bearer ID, PDU session ID, and DRB ID.

[0100] FIG. 15 is a diagram showing a configuration example of each device in the mobile NW system 100g in Modification 1 of the fourth embodiment. In the example shown in FIG. 15, compared with FIG. 14, the flag change unit 22-1 is not provided in the Ph-GW20g-1, the flag change unit 22-2 is not provided in the Ph-GW20g-2, and the wireless terminal 45g is not provided with the flag generation unit 46. Further, the control device 40g is provided with a priority change calculation unit 43g instead of the priority change calculation unit 43f.

[0101] The priority change calculation unit 43g determines the target radio section ID and the priority to be changed based on the information of the radio section. Then, the priority change calculation unit 43g generates a control signal including the target radio section ID and the priority to be changed. The priority change calculation unit 43g transmits the generated control signal to all of the Ph-GW20g-1 and 20g-2. For example, the control device 40g determines the current communication based on the target radio section ID of the traffic, and transmits an instruction to lower the priority for the uplink traffic and raise the priority for the downlink traffic.

[0102] (Modification 2 in the Fourth Embodiment) The control device 40f may be configured to perform priority change using the traffic volume as in the first and second embodiments, rather than prior priority change using the traffic equivalent for calculating the congestion delay.

[0103] (Modification 3 in the Fourth Embodiment) In the above-described embodiment, the control device 40f is configured to increase the priority for round-trip communication that satisfies the delay requirement for the Ph-GW20d so that one-way traffic is preferentially transmitted, and to lower the priority of the round-trip communication so that the delay requirement for one-way communication is satisfied for the downlink. The control device 40f may give other instructions as long as it can change the priority of the traffic so that one-way traffic is preferentially transmitted.

[0104] (Fifth Embodiment) In the fifth embodiment, a configuration for controlling the delay requirement of the application so as to satisfy the delay requirement of the application including the processing delay time of the server as the reciprocating delay time will be described.

[0105] FIG. 16 is a diagram showing a configuration example of each device in the mobile NW system 100h according to the fifth embodiment. FIG. 16 shows a base station 10d, a Ph-GW 20d-1, a Ph-GW 20b-2, a server 30h, a control device 40h, and a wireless terminal 45. Here, the specific configurations of the server 30 and the control device 40h will be described. Note that the other configurations and processes are the same as those in the third and fourth embodiments.

[0106] The server 30h includes a flag generation unit 31 and a processing delay measurement unit 32. When it is necessary to transmit downlink traffic, the flag generation unit 31 generates a flag to be added to the downlink traffic and adds the flag to the downlink traffic.

[0107] The processing delay measurement unit 32 measures the delay time related to the processing of the server 30h (hereinafter referred to as "processing delay time") at regular intervals. More specifically, the processing delay measurement unit 32 measures the processing time from the reception of uplink traffic to the transmission of downlink traffic as the processing delay time. The processing delay measurement unit 32 transmits the information on the measured processing delay time to the control device 40h. As a method of notifying the information on the processing delay time, it may be directly notified from the server 30h by wireless or the like, or may be notified using the transmission path through which the main signal flows.

[0108] The processing delay measurement unit 32 measures when a new flow occurs and does not perform subsequent measurements, or may store in advance the relationship between the traffic volume and the processing delay time of the server 30. The processing delay measurement unit 32 may feedback based on the measured delay time from the previously measured processing delay time. This is effective for shortening the measurement interval and improving the delay accuracy.

[0109] The control device 40h includes a required delay calculation unit 41, a traffic-specific congestion calculation unit 42, a priority change calculation unit 43, and a delay determination unit 44h. The control device 40h is different in configuration from the control device 40d in that it includes the delay determination unit 44h instead of the delay determination unit 44.

[0110] The delay determination unit 44h calculates the delay time based on the delay information of the wired section acquired from the Ph-GW20d-1, the delay information of the wireless section acquired from the base station 10d, the congestion delay, and the information on the processing delay time acquired from the server 30b. The delay determination unit 44h determines whether the calculated delay time satisfies the required delay.

[0111] The priority change calculation unit 43 changes the priority by the method shown in the third or fourth embodiment based on the delay time calculated by the delay determination unit 44h.

[0112] According to the mobile NW system 100h configured as described above, the delay time is calculated including the processing delay of the server 30h. In this way, in the mobile NW system 100h, by including the processing delay of the server 30h, it is possible to determine whether the delay requirement of the application is satisfied. As a result, in the mobile NW system 100h in which one-way communication and round-trip communication are mixed, it is possible to realize highly accurate communication control based on the required quality.

[0113] (Modification Example 1 in the Fifth Embodiment) The fifth embodiment may be modified in the same manner as the fourth embodiment.

[0114] Among the functional parts of the above-described control devices 40, 40a, 40c, 40d, 40e, 40f, 40g, and 40h, some or all are realized as software by a processor such as a CPU (Central Processing Unit) executing a program stored in a storage device having a non-volatile recording medium (non-temporary recording medium) and a storage unit. The program may be recorded on a computer-readable non-temporary recording medium. A computer-readable non-temporary recording medium is, for example, a non-temporary recording medium such as a flexible disk, a magneto-optical disk, a ROM (Read Only Memory), a portable medium such as a CD-ROM (Compact Disc Read Only Memory), or a storage device such as a hard disk built into a computer system.

[0115] Among the functional parts of the above-described control devices 40, 40a, 40c, 40d, 40e, 40f, 40g, and 40h, some or all may be realized using hardware including an electronic circuit (electronic circuit or circuitry) using, for example, an LSI (Large Scale Integrated circuit), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), or an FPGA (Field Programmable Gate Array).

[0116] As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and designs and the like within the scope not departing from the gist of the present invention are also included.

Industrial Applicability

[0117] The present invention can be applied to optical communication system technologies such as optical access systems in which one-way communication and two-way communication coexist.

Explanation of Signs

[0118] 10, 10d…Base station, 11…Information acquisition unit, 20, 20-1 to 20-2, 20b-1 to 20b-2, 20d-1…Ph-GW, 21…Priority change unit, 22…Flag change unit, 30…Server, 31…Flag generation unit, 32…Processing delay measurement unit, 40, 40a, 40c, 40d, 40e, 40f, 40g, 40h…Control device, 41…Required delay calculation unit, 42…Congestion calculation by traffic type, 43, 43a, 43c, 43d, 43e, 43f, 43g, 43h…Priority change calculation unit, 44…Delay determination unit, 45…Wireless terminal, 46…Flag generation unit, 50…Core network, 100, 100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h…Mobile NW system, 411…Wireless quality information collection unit, 412…Required delay calculation unit, 413…Traffic priority calculation unit, 414…Traffic allocation information collection unit, 415…Traffic volume calculation unit, 421…Sorting by traffic priority, 422…Congestion delay calculation by priority

Claims

1. A control device in a communication system in which one-way communication and round-trip communication coexist, Based on cooperation information indicating a communication state between a plurality of wireless terminals and a base station that performs wireless communication with the plurality of wireless terminals, obtained from traffic transmitted from the plurality of wireless terminals, a request delay acquisition unit that acquires information on request delay and information on priority for each traffic; A traffic-specific congestion calculation unit that calculates a congestion delay in a wired section based on the information on the request delay and the information on the priority acquired for each traffic by the request delay acquisition unit; Based on the congestion delay in the wired section calculated by the traffic-specific congestion calculation unit, when congestion occurs or the total delay requirement is not satisfied, a priority change control unit that transmits a control signal including an instruction to change the priority of one-way communication traffic or the priority of round-trip communication traffic so that the one-way communication traffic is preferentially transmitted to a relay device that relays the traffic; A control device comprising:

2. A flag for identifying whether the traffic transmitted from the plurality of wireless terminals is one-way communication traffic or round-trip communication traffic is added to the traffic transmitted from the plurality of wireless terminals, The priority change control unit identifies whether each of the traffic transmitted from the plurality of wireless terminals is one-way communication traffic or round-trip communication traffic based on the flag added to the traffic, and transmits a control signal including an instruction to change the priority of any of the identified traffic to the relay device, The control device according to claim 1.

3. The priority change control unit An instruction to increase the priority of the one-way communication traffic above the priority of the round-trip communication traffic without changing the priority of the round-trip communication traffic, An instruction to lower the priority of the round-trip communication traffic below the priority of the one-way communication traffic without changing the priority of the one-way communication traffic, or Transmits a control signal including any of an instruction to increase the priority of the one-way communication traffic above the priority of the round-trip communication traffic and to lower the priority of the round-trip communication traffic below the priority of the one-way communication traffic to the relay device, The control device according to claim 1 or 2.

4. The cooperation information includes at least delay information on a wireless section between the plurality of wireless terminals and the base station, Based on the delay information of the wired section obtained from the relay device, the delay information of the wireless section included in the cooperation information, and the congestion delay in the wired section calculated by the traffic-specific congestion calculation unit, calculate a delay time, and further include a delay determination unit that determines whether the calculated delay time satisfies the required delay. When the delay time does not satisfy the required delay and the required delay of the round-trip communication is satisfied as a result of changing the priority of the round-trip communication, the priority change control unit transmits a control signal including the instruction to the relay device. The control device according to claim 1 or 2.

5. The cooperation information includes at least delay information of a wireless section between the plurality of wireless terminals and the base station. Based on the delay information of the wired section obtained from the relay device, the delay information of the wireless section included in the cooperation information, and the congestion delay in the wired section calculated by the traffic-specific congestion calculation unit, calculate a delay time, and further include a delay determination unit that determines whether the calculated delay time satisfies the required delay. When there is a round-trip communication where the delay time does not satisfy the required delay and all communications satisfy the required delay as a result of changing the priority, the priority change control unit transmits a control signal including the instruction to the relay device. The control device according to claim 1 or 2.

6. The cooperation information includes at least delay information of a wireless section between the plurality of wireless terminals and the base station. Based on the delay information of the wired section obtained from the relay device, the delay information of the wireless section included in the cooperation information, the congestion delay in the wired section calculated by the traffic-specific congestion calculation unit, and information on the processing time from the reception of the upstream traffic measured at the server located above the relay device to the transmission of the downstream traffic, calculate a delay time, and further include a delay determination unit that determines whether the calculated delay time satisfies the required delay. When there is a round-trip communication where the delay time does not satisfy the required delay and all communications satisfy the required delay as a result of changing the priority, the priority change control unit transmits a control signal including the instruction to the relay device. The control device according to claim 1 or 2. The control device according to claim 1.

7. A priority control method performed by a control device in a communication system in which one-way communication and round-trip communication coexist. Based on the cooperation information indicating the communication state between the base station that performs wireless communication with the plurality of wireless terminals, obtained from the traffic transmitted from the plurality of wireless terminals, information on the required delay and information on the priority in the traffic are acquired for each traffic, Based on the information on the required delay acquired for each traffic and the information on the priority, the congestion delay in the wired section is calculated, Based on the calculated congestion delay in the wired section, when congestion occurs or the total delay requirement is not satisfied, a control signal including an instruction to change the priority of the one-way communication traffic or the priority of the round-trip communication traffic so that the one-way communication traffic is preferentially transmitted is transmitted to the relay device that relays the traffic.

Images