JP7347677B2 - Bandwidth control system, band control method, band control program, and in-office optical termination device - Google Patents

Description

The present disclosure relates to a band control system, a band control method, a band control program, and an in-office optical terminal device.

In the FTTH (Fiber To The Home) service, an optical line terminal (OLT) connects multiple optical line terminals (ONU) through time division multiplexing (TDM). Network Unit) There are cases where In such FTTH services, a PON (Passive Optical Network) method, particularly GE-PON (Gigabit Ethernet PON (Ethernet is a registered trademark)) capable of transmission speeds of gigabit class, may be adopted. In a PON system including a GE-PON, the OLT can be equipped with a DBA (Dynamic Bandwidth Allocation) function that dynamically allocates the bandwidth for upstream communication from the ONU to the OLT according to the amount of traffic. In PON, MPCP (Multi Point Control Protocol) is used to realize bandwidth control in communication from ONU to OLT (see, for example, Non-Patent Documents 1, 2, and 3).

"IEEE Standard for Ethernet", IEEE802.3-2015, section.5. T.Tatsuta et al., "Design philosophy and performance of a GE-PON system for mass Deployment", Journal of Optical Networking, vol.6, no.6, pp689-700, 2007. S.Hatta et al., "Implementation of ultra-low latency dynamic bandwidth allocation method for TDM-PON", IEICE Communication Express, vol.5, no.11, pp418-423, 2016.

In the bandwidth control systems as shown in Non-Patent Documents 1 to 3, dynamic bandwidth allocation (DBA) is periodically performed according to the amount of traffic. Then, by dividing the DBA cycle into a report transmission time and a data transmission time, and having the ONU (in-home optical terminal unit) transmit traffic volume report information during the report transmission time, bandwidth is allocated according to the traffic volume. has been realized. Since it is necessary to transmit report information from each in-home optical terminal device in each DBA cycle, the data transmission time within the DBA cycle is limited, and the band usage efficiency is limited.

The present disclosure has been made to solve such problems. The purpose of this is to provide a bandwidth that can respond to fluctuations in the amount of traffic that the in-home optical terminal equipment requests to transmit, secure data transmission time within the DBA cycle, and improve bandwidth utilization efficiency. The object of the present invention is to provide a control system, a band control method, a band control program, and an in-office optical termination device.

A band control system according to the present disclosure is a communication system that communicates optical signals between an in-office optical termination device and a plurality of in-home optical termination devices, wherein the plurality of in-home optical termination devices receive reports from the in-office optical termination devices. Report information is transmitted to the in-office optical termination device in accordance with the request, and the in-office optical termination device is configured to transmit data from each of the plurality of in-home optical termination devices to the in-office optical termination device based on the report information. A band control system for allocating a band, wherein the in-office optical termination device includes a report value determination unit that determines a report value for each of the plurality of in-home optical termination devices based on the report information received in the past; Based on the report value determined by the report value determination unit, a band for transmitting data from each of the plurality of in-home optical termination devices to the in-office optical termination device is allocated for each preset band allocation cycle. an allocation unit; an evaluation unit that calculates an evaluation value for each of the plurality of in-home optical terminal devices based on the report information received in the past; a report request determination unit that determines whether or not to transmit the report request to each of the in-home optical terminal devices; is determined to be either a first report request that causes the report information to be transmitted at a report transmission time within the band allocation cycle, or a second report request that causes the report information to be transmitted at a data transmission time that is within the band allocation cycle. do.

A band control method according to the present disclosure provides a communication system in which optical signals are communicated between an in-office optical termination device and a plurality of in-home optical termination devices, wherein the plurality of in-home optical termination devices receive reports from the in-office optical termination devices. Report information is transmitted to the in-office optical termination device in accordance with the request, and the in-office optical termination device is configured to transmit data from each of the plurality of in-home optical termination devices to the in-office optical termination device based on the report information. A band control method for allocating a band, the report value determining step of determining a report value for each of a plurality of in-house optical terminal devices based on the report information received in the past by the in-house optical terminal device; Allocating a band for transmitting data from each of the plurality of in-home optical termination devices to the in-office optical termination device, based on the report value determined in the value determination step, for each preset band allocation cycle. an evaluation step of calculating an evaluation value for each of the plurality of in-home optical termination devices based on the report information received in the past by the in-office optical termination device; a report request determining step of determining whether or not to transmit the report request to each of the plurality of in-home optical terminal devices based on the report request determining step, the report request determining step determining whether to transmit the report request to each of the plurality of in-home optical terminal devices. In this case, the report request is a first report request that causes the report information to be transmitted at a report transmission time within the band allocation cycle, and a second report request that causes the report information to be transmitted at a data transmission time that is within the band allocation cycle. including the step of determining one of the following.

A band control program according to the present disclosure provides a communication system in which optical signals are communicated between an in-office optical termination device and a plurality of in-home optical termination devices, in which the plurality of in-home optical termination devices receive signals from the in-office optical termination devices. Report information is transmitted to the in-office optical termination device in accordance with the report request, and the in-office optical termination device transmits data from each of the plurality of in-home optical termination devices to the in-office optical termination device based on the report information. A bandwidth control program for operating a bandwidth control system that allocates a band to a plurality of in-house optical terminals based on the report information received in the past by the in-office optical termination device in a computer of the in-office optical termination device. a report value determination step of determining a report value for each of the optical termination devices, and a plurality of the in-home optical termination devices for each preset band allocation period based on the report value determined in the report value determination step. an allocation step of allocating a band for transmitting data from each of the in-house optical terminal devices to the in-house optical terminal device; and an evaluation of each of the plurality of in-home optical terminal devices based on the report information received in the past by the in-house optical terminal device. an evaluation step of calculating a value; and a report request determination step of determining whether or not to transmit the report request to each of the plurality of in-home optical terminal devices based on the evaluation value calculated in the evaluation step. , and in the report request determination step, when it is determined to transmit the report request, the report request is a first report request that causes the report information to be transmitted at a report transmission time within the band allocation period; and a second report request that causes the report information to be transmitted at a data transmission time within a band allocation period.

An in-office optical termination device according to the present disclosure is an in-office optical termination device that allocates a band for transmitting data from each of a plurality of in-home optical termination devices based on report information transmitted from the plurality of in-home optical termination devices. a report value determination unit that determines a report value for each of the plurality of in-home optical terminal devices based on the report information received in the past; , an allocation unit that allocates a band for transmitting data from each of the plurality of in-home optical termination devices to the in-office optical termination device for each preset band allocation cycle; , an evaluation unit that calculates an evaluation value for each of the plurality of in-home optical termination devices, and transmitting the report request to each of the plurality of in-home optical termination devices based on the evaluation value calculated by the evaluation unit. a report request determination unit that determines whether or not to transmit the report request, and when the report request determination unit determines whether to transmit the report request, the report request determination unit transmits the report request at a report transmission time within the band allocation period. A decision is made between a first report request that causes information to be transmitted and a second report request that causes the report information to be transmitted within the data transmission time within the band allocation period.

According to the bandwidth control system, bandwidth control method, bandwidth control program, and in-office optical terminal device according to the present disclosure, the data transmission time within the DBA cycle can be This has the effect that it is possible to secure the bandwidth and improve the band usage efficiency.

1 is a diagram schematically showing the overall configuration of a communication system to which a band control system according to a first embodiment is applied. FIG. 2 is a block diagram showing the configuration of an intra-office optical termination device of the band control system according to Embodiment 1. FIG. FIG. 2 is a flow diagram illustrating an example of the operation of the bandwidth control system according to the first embodiment. FIG. 2 is a diagram illustrating an example of the operation of the bandwidth control system according to the first embodiment.

Embodiments for implementing a band control system according to the present disclosure will be described with reference to the accompanying drawings. In each figure, the same or corresponding parts are given the same reference numerals, and overlapping explanations will be simplified or omitted as appropriate. In the following description, for convenience, the positional relationship of each structure may be expressed based on the illustrated state. Note that the present disclosure is not limited to the following embodiments, and any combination of embodiments, modification of any component of each embodiment, or modification of each embodiment may be made without departing from the spirit of the present disclosure. Any component of the embodiment can be omitted.

Embodiment 1.
Embodiment 1 of the present disclosure will be described with reference to FIGS. 1 to 4. FIG. 1 is a diagram schematically showing the overall configuration of a communication system to which a band control system is applied. FIG. 2 is a block diagram showing the configuration of the intra-office optical terminal device of the band control system. FIG. 3 is a flow diagram showing an example of the operation of the bandwidth control system. FIG. 4 is a diagram illustrating an example of the operation of the band control system.

A communication system to which the band control system according to this embodiment is applied is a communication system in which optical signals are communicated between an in-house optical termination device 100 and a plurality of in-home optical termination devices 20. As shown in FIG. 1, the communication system includes an in-office optical termination device 100 and a plurality of in-home optical termination devices 20. In the present disclosure, the side of the in-home optical termination device 100 may be referred to as the "upstream side," and the side of the in-home optical termination device 20 may be referred to as the "downstream side." The in-house optical termination device 100 is communicably connected to each of the plurality of in-home optical termination devices 20 via the optical branching unit 10 . The communication network configured as described above is a so-called PON (Passive Optical Network).

The intra-office optical termination device 100 is communicably connected to the upstream external network 1. Each of the plurality of in-home optical terminal devices 20 is communicably connected to the downstream external network 2. The optical signal transmitted from the in-home optical termination device 100 is branched at the optical branching unit 10 and sent to each of the plurality of in-home optical termination devices 20 . Optical signals transmitted from each of the plurality of in-home optical termination devices 20 are multiplexed by the optical branching unit 10 and reach the in-home optical termination device 100 .

In a communication network (PON) as shown in FIG. 1, when transmitting data from a plurality of in-home optical termination devices 20 to an in-office optical termination device 100, a band is allocated to each of the plurality of in-home optical termination devices 20. This avoids signal collision after multiplexing in the optical branching section 10. Band allocation at this time is performed by temporally separating data transmission from each of the plurality of in-home optical termination devices 20 to the in-office optical termination device 100. That is, band allocation in the present disclosure means allocating a time during which data transmission from each of the plurality of in-home optical termination devices 20 to the in-office optical termination device 100 is permitted.

In the band control system of this embodiment, band allocation is performed dynamically according to the amount of data transmitted from each of the plurality of in-home optical termination devices 20 to the in-office optical termination device 100 (hereinafter also referred to as "traffic amount"). It will be held on. In other words, the traffic amount of each of the plurality of in-home optical terminal devices 20 is the amount of uplink data stored in the buffer of each in-home optical terminal device 20. That is, in the communication network of this embodiment, dynamic bandwidth allocation (DBA) is adopted.

In DBA, the in-house optical terminal device 100 transmits a report request to each of the plurality of in-home optical terminal devices 20. Each of the plurality of in-home optical termination devices 20 transmits report information to the in-office optical termination device 100 in accordance with a report request from the in-office optical termination device 100. The report information from the in-home optical termination device 20 includes information regarding the amount of traffic requested by the in-home optical termination device 20. The in-office optical terminal device 100 then selects a band for transmitting data from each of the plurality of in-home optical terminal devices 20 to the in-office optical terminal device 100 based on the received report information from each in-home optical terminal device 20. assign.

Next, with reference to FIG. 2, the configuration of the intra-office optical termination device 100 included in the band control system according to this embodiment will be described. As shown in the figure, the in-office optical termination device 100 includes a PON section 101, a report receiving section 111, a DBA calculation section 112, a Gate generation section 113, a report value determination section 121, an evaluation section 122, and a report request determination section 123. ing.

The intra-office optical terminal device 100 includes, as hardware, a computer having a processor and a memory. The processor is also referred to as a CPU (Central Processing Unit), central processing unit, processing unit, arithmetic unit, microprocessor, microcomputer, or DSP. Examples of the memory include nonvolatile or volatile semiconductor memories such as RAM, ROM, flash memory, EPROM, and EEPROM, or magnetic disks, flexible disks, optical disks, compact disks, minidisks, and DVDs.

A program as software is stored in the memory of the intra-office optical termination device 100. Then, the in-office optical terminal device 100 executes preset processing by the processor executing the program stored in the memory, and as a result of the cooperation of the hardware and software, the PON unit 101 and the report receiving unit 111, a DBA calculation section 112, a Gate generation section 113, a report value determination section 121, an evaluation section 122, and a report request determination section 123.

The PON section 101 has a function of transmitting and receiving data to and from the upstream external network 1 and each of the plurality of in-home optical terminal devices 20 . The report receiving unit 111 extracts report information from the data transmitted from the plurality of in-home optical terminal devices 20 and received by the PON unit 101 of the in-home optical terminal device 100. The report information extracted by the report receiving unit 111 is stored in the memory of the intra-office optical termination device 100, for example.

The report value determining unit 121 determines a report value for each of the plurality of in-home optical terminal devices 20 based on the report information extracted by the report receiving unit 111. The report information extracted by the report receiving unit 111 can be rephrased as report information that the intra-office optical terminal device 100 has received in the past. The report value is the traffic amount of the in-home optical terminal device 20 determined based on the report information. Details of how the report value determination unit 121 determines the report value will be described later.

The DBA calculation unit 112 is an allocation unit that allocates a band for transmitting data from each of the plurality of in-home optical termination devices 20 to the in-office optical termination device 100 based on the report value determined by the report value determination unit 121. . The DBA calculation unit 112 allocates bands for each DBA cycle. The DBA cycle is a preset band allocation cycle. Report information from the home optical terminal device 20 is, in principle, transmitted every DBA cycle. Therefore, the report value determination unit 121 determines the report value for each DBA cycle. The DBA calculation unit 112 then allocates a band based on the report value for each DBA cycle. In band allocation, the DBA calculation unit 112 calculates the data transmission start time and transmission duration time for each of the plurality of in-home optical terminal devices 20. Then, the DBA calculation unit 112 generates Grant information including the calculated transmission start time and transmission duration time.

The Gate generation unit 113 generates a Gate frame including the Grant information generated by the DBA calculation unit. The Gate frame is a type of control frame defined by MPCP (Multipoint Control Protocol). The Gate frame generated by the Gate generation unit 113 is transmitted to each of the plurality of in-home optical terminal devices 20 by the PON unit 101. Note that an MPCP report frame is used to transmit the report information from the in-home optical termination device 20 to the in-office optical termination device 100.

The in-home optical termination device 20 that has received the Gate frame transmits data to the in-office optical termination device 100 according to the Grant information included in the Gate frame. In this way, each of the plurality of in-home optical termination devices 20 transmits data to the in-office optical termination device 100 using the band (time) assigned for each DBA cycle.

The evaluation unit 122 calculates an evaluation value for each of the plurality of in-home optical termination devices based on the report information extracted by the report reception unit 111, that is, the report information that the in-home optical termination device 100 has received in the past. Then, the report request determination unit 123 determines whether or not to transmit a report request to each of the plurality of in-home optical terminal devices 20 based on the evaluation value calculated by the evaluation unit 122. The evaluation unit 122 calculates an evaluation value for each DBA cycle. Then, the report request determining unit 123 determines whether or not to transmit a report request to each of the plurality of in-home optical terminal devices 20 in each DBA cycle.

Here, the DBA cycle, which is the band allocation cycle, is divided into a report transmission time and a data transmission time. The report transmission time is a time period during which the in-home optical terminal device 20 transmits report information. The data transmission time is a time period during which the in-home optical terminal device 20 mainly transmits data. When the report request determination unit 123 of this embodiment determines to transmit a report request, it determines the report request to be transmitted as either the first report request or the second report request. The first report request is a report request that causes the in-home optical terminal device 20 to transmit report information at a report transmission time within the DBA cycle. The second report request is a report request that causes the in-home optical terminal device 20 to transmit report information at the data transmission time within the DBA cycle.

The Gate generation unit 113 generates a Gate frame including a report request according to the content determined by the report request determination unit 123. The Gate frame including the report request generated by the Gate generation unit 113 is transmitted by the PON unit 101 to each of the plurality of in-home optical terminal devices 20.

As described above, each of the plurality of in-home optical termination devices 20 transmits report information to the in-office optical termination device 100 in accordance with a report request from the in-office optical termination device 100. That is, the home optical terminal device 20 that has received the first report request transmits report information at the report transmission time within the next DBA cycle. Furthermore, the in-home optical terminal device 20 that has received the second report request transmits report information at the data transmission time within the next DBA cycle. In this case, the in-home optical terminal device 20 superimposes report information on data and transmits the report information. Then, the in-home optical terminal device 20 that has not received the report request does not transmit report information in the next DBA cycle.

Next, the determination of a report value by the report value determination unit 121 of this embodiment will be explained. As described above, in the band control system of this embodiment, there are cases in which report information is transmitted from the in-home optical termination device 20 and cases in which report information is not transmitted from the in-home optical termination device 20. When the in-office optical termination device 100 receives the report information transmitted from the in-home optical termination device 20, the report value determination unit 121 determines the amount of traffic included in the report information received by the in-office optical termination device 100. The report value is 20.

On the other hand, if the report information is not transmitted from the in-home optical termination device 20 and the in-office optical termination device 100 does not receive the report information, the report value determination unit 121 determines the Based on the traffic amount included in the report information of the terminal device 20, the report value of the in-home optical terminal device 20 is determined. In this case, specifically, the report value determining unit 121 determines the average amount of traffic included in the report information received the most recent n times (n is a preset integer of 2 or more) for the in-home optical terminal device 20. Let the value be the report value of the in-home optical terminal device 20.

Here, as described above, the report information received by the in-home optical termination device 20 is extracted by the report receiving section 111 and stored in the memory of the in-home optical termination device 100, for example. Then, the report value determining unit 121 determines a report value based on the report information extracted by the report receiving unit 111. In order to enable the report value determination unit 121 to calculate the average value for the most recent n times, the in-office optical termination device 100 stores report information for the most recent n times for each of the plurality of in-home optical termination devices 20.

Next, calculation of an evaluation value by the evaluation unit 122 of this embodiment will be explained. In the bandwidth control system of this embodiment, the evaluation unit 122 uses two evaluation values: a first evaluation value i and a second evaluation value k. The first evaluation value i is an evaluation value calculated based on a change in the report value of the report information. The second evaluation value k is an evaluation value that changes depending on whether or not the intra-office optical termination device 100 has received report information. The initial values of the first evaluation value i and the second evaluation value k are both 0.

First, the first evaluation value i will be explained. When the in-home optical termination device 100 receives report information from the in-home optical termination device 20, the evaluation unit 122 calculates the first evaluation value i. In calculating the first evaluation value i, the evaluation unit 122 first determines whether the fluctuation in the report value of the report information is equal to or less than the fluctuation standard. The determination as to whether the fluctuation in the report value of the report information is equal to or less than the fluctuation standard is performed, for example, by determining whether the following equation (1) holds true.

|R(j,N)-Rave|≦s... (1)

In equation (1), R(j, N) is a report value of report information transmitted from the j-th in-home optical terminal device 20 in the N-th period (N is an integer of 1 or more). Incidentally, each of the plurality of in-home optical terminal devices 20 is assigned a serial number in advance. Moreover, Rave is the average value of the report values of the report information received the most recent n times (n is a preset integer of 2 or more) for the j-th in-home optical terminal device 20. Further, s is the standard deviation of the report value of the report information received most recently for the j-th in-home optical terminal device 20.

Note that the evaluation unit 122 may evaluate fluctuations in report values using other indicators representing variations in report values instead of the standard deviation s. For example, when using the variance s^2 of report values of report information received most recently n times as an index instead of the standard deviation s, the evaluation unit 122 determines whether the following equation (2) holds. Then, it may be determined whether the fluctuation in the report value of the report information is below the fluctuation standard.

(R(j,N)-Rave)^2≦s^2... (2)

When formula (1) is used, if formula (1) holds true, the evaluation unit 122 determines that the fluctuation in the report value of the report information is below the fluctuation standard. Then, when it is determined that the fluctuation in the report value of the report information is equal to or less than the fluctuation standard, the evaluation unit 122 adds 1 to the first evaluation value i. On the other hand, if equation (1) does not hold, the evaluation unit 122 determines that the fluctuation in the report value of the report information is not below the fluctuation standard. If it is determined that the variation in the report value of the report information is not below the variation standard, the evaluation unit 122 subtracts 1 from the first evaluation value i. However, the first evaluation value i shall not be less than 0.

Next, the second evaluation value k will be explained. When the in-home optical termination device 100 receives report information from the in-home optical termination device 20, the evaluation unit 122 sets the second evaluation value k to the same value as the first evaluation value i. On the other hand, if the in-home optical termination device 100 does not receive the report information from the in-home optical termination device 20, the evaluation unit 122 subtracts 1 from the second evaluation value k.

The report request determining unit 123 determines to transmit a first report request for the in-home optical terminal device 20 whose first evaluation value i is 0. An evaluation value where the first evaluation value i is 0 corresponds to a case where the fluctuation of the report value of the report information is not below the fluctuation standard. That is, the report request determining unit 123 determines the report request to be the first report request when the evaluation value corresponds to a case where the fluctuation of the report value of the report information is not less than the fluctuation standard.

Further, the report request determination unit 123 determines to transmit a second report request for the in-home optical terminal device 20 for which the first evaluation value i is 1 or more and the second evaluation value k is 1 or less. An evaluation value in which the first evaluation value i is 1 or more corresponds to a case where the fluctuation in the report value of the report information is equal to or less than the fluctuation standard. That is, the report request determination unit 123 determines the report request to be the second report request when the evaluation value corresponds to a case where the fluctuation of the report value of the report information is equal to or less than the fluctuation standard.

Then, the report request determination unit 123 determines not to transmit a report request for the in-home optical terminal device 20 for which the first evaluation value i is 1 or more and the second evaluation value k exceeds 1. An evaluation value where the second evaluation value k exceeds 1 corresponds to a case where report information in which the fluctuation of the report value is equal to or less than the fluctuation standard is received at least twice. That is, the report request determination unit 123 determines not to transmit a report request when the evaluation value corresponds to the case where report information in which the fluctuation of the report value is equal to or less than the fluctuation standard is received at least twice.

Next, an example of the processing flow of the bandwidth control method in the bandwidth control system configured as described above will be described with reference to the flowchart of FIG. 3. In the same figure, the report transmission time and data transmission time of the DBA cycle are expressed as Report Block and Data Block, respectively. Further, the process shown in FIG. 3 is performed for each of the plurality of in-home optical termination devices 20.

First, in step S11, the evaluation unit 122 initializes each of the first evaluation value i and the second evaluation value k to zero. Further, the intra-office optical termination device 100 initializes a variable N to 1, which counts the number of the target DBA cycle. In the following step S12, the intra-office optical termination device 100 waits until the Report Block ends within the current DBA cycle, that is, the Nth DBA cycle, and when the Report Block ends, the process proceeds to Step S13.

In step S13, the report receiving unit 111 receives data from the end of the Report Block in the (N-1)th DBA cycle (the previous DBA cycle) to the end of the Report Block in the Nth DBA cycle (current DBA cycle). , it is determined whether the in-office optical termination device 100 has received report information regarding the in-home optical termination device 20. When the in-office optical termination device 100 has received report information regarding the in-home optical termination device 20, the report receiving unit 111 extracts the report information from the data received by the PON unit 101 of the in-office optical termination device 100. , the process proceeds to step S14. In step S14, the report value determination unit 121 sets the traffic volume of report information received by the in-home optical terminal device 100 in the current DBA cycle as the report value R of the in-home optical terminal device 20.

On the other hand, if the in-home optical terminal device 20 has not received the report information in step S13, the report receiving unit 111 does not extract the report information and the process proceeds to step S15. In step S15, the report value determining unit 121 calculates the average value of the most recent n times of the traffic volume included in the report information received in the past regarding the in-home optical terminal device 20, as the report value R of the in-home optical terminal device 20. shall be.

After step S14, the process proceeds to step S21. In step S21, the evaluation unit 122 performs evaluation using equation (1) described above. If equation (1) holds true, the process proceeds to step S22. In step S22, the evaluation unit 122 adds 1 to the first evaluation value i. On the other hand, if equation (1) does not hold in step S21, the process proceeds to step S23. In step S22, the evaluation unit 122 sets the larger of the value obtained by subtracting 1 from the first evaluation value i and 0 as the first evaluation value i. After step S22 or S23, the process proceeds to step S24. In step S24, the evaluation unit 122 sets the second evaluation value k to a value equal to the first evaluation value i updated in step S22 or S23.

Further, after step S15, the process proceeds to step S25. In step S25, the evaluation unit 122 subtracts 1 from the second evaluation value k.

After step S24, the process proceeds to step S31. In step S31, the report request determination unit 123 determines whether the first evaluation value i is 0 or 1 or more. If the first evaluation value i is 0, the process proceeds to step S32. In step S32, the report request determination unit 123 determines to transmit the first report request to the in-home optical terminal device 20. That is, report information is transmitted using Report Block for the in-home optical terminal device 20.

On the other hand, if the first evaluation value i is 1 or more in step S31, the process advances to step S33. Also, after step S25, the process proceeds to step S33. In step S33, the report request determination unit 123 determines whether the second evaluation value k is less than or equal to 1 or greater than 1. If the second evaluation value k is 1 or less, the process proceeds to step S34. In step S<b>34 , the report request determination unit 123 determines to transmit the second report request to the in-home optical terminal device 20 . That is, the report information is transmitted using Data Block regarding the in-home optical terminal device 20. In this case, in the subsequent step S35, the report value determining unit 121 adds 84 [bytes] to the report value R of the in-home optical terminal device 20. This 84 [byte] is the total of the data size of the report information and the minimum value of the Ethernet (registered trademark) preamble/IFG.

On the other hand, if the second evaluation value k is greater than 1 in step S33, the process proceeds to step S36. In step S<b>36 , the report request determination unit 123 determines not to transmit a report request to the in-home optical terminal device 20 . Therefore, the report information transmission from the home optical terminal device 20 in the next DBA cycle is skipped.

After step S32, S35 or S36, the process proceeds to step S41. In step S41, the DBA calculation unit 112 calculates bandwidth allocation based on the report value R determined in step S14, S15, or S35. In subsequent step S42, the evaluation unit 122 calculates the average value and standard deviation of the report values to be used for evaluation in the next DBA cycle. After step S42, the process proceeds to step S43, and 1 is added to the DBA cycle count variable N. When the process of step S43 is completed, the process returns to step S12, and the local optical terminal device 100 performs the same process for the next DBA cycle.

In the above bandwidth control method, steps S14 and S15 correspond to a report value determining step. The report value determination step is a step of determining a report value for each of the plurality of in-home optical termination devices 20 based on report information that the in-home optical termination device 100 has received in the past. Step S41 corresponds to an allocation step. The allocation step is performed when transmitting data from each of the plurality of in-home optical termination devices 20 to the in-office optical termination device 100 for each preset band allocation cycle based on the report value determined in the report value determination step. This is the step of allocating a band.

Further, steps S21 to S25 correspond to evaluation steps. The evaluation step is a step of calculating an evaluation value for each of the plurality of in-home optical termination devices 20 based on report information that the in-home optical termination device 100 has received in the past.

Steps S31 to S36 correspond to a report request determination step. The report request determination step is a step of determining whether or not to transmit a report request to each of the plurality of in-home optical terminal devices 20 based on the evaluation value calculated in the evaluation step. In the report request determination step, the report request is divided into a first report request for transmitting report information at a report transmission time within the bandwidth allocation period and a second report request for transmitting report information at a data transmission time within the bandwidth allocation period. It includes steps S32 and S34 for determining either of the following.

In addition, as described above, when the in-office optical termination device 100 is equipped with a computer, the computer of the in-office optical termination device 100 is controlled by a program into the PON section 101, the report reception section 111, the DBA calculation section 112, the Gate generation section 113, and the report generation section 113. It functions as each part of the value determination part 121, the evaluation part 122, and the report request determination part 123. This program is a bandwidth control program for operating a bandwidth control system. Further, this program is also a band control program that causes the computer of the intra-office optical termination device 100 to execute the above band control method. This band control program causes the computer of the intra-office optical termination device 100 to execute the aforementioned report value determination step, allocation step, evaluation step, and report request determination step.

An example of the operation of the bandwidth control system and bandwidth control method configured as described above will be described with reference to FIG. 4. In the figure, similarly to FIG. 3, the report transmission time and data transmission time of the DBA cycle are expressed as Report Block and Data Block, respectively. Further, OLT in the figure is an abbreviation for Optical Line Terminal, and corresponds to the intra-office optical termination device 100. ONU in the figure is an abbreviation for Optical Network Unit, and corresponds to the in-home optical terminal device 20.

The first evaluation value i and the second evaluation value k are 0, and in this case, the first report request is sent from the in-home optical termination device 100 to the in-home optical termination device 20, so the in-home optical termination device 20 uses Report Block. Submit report information. The intra-office optical terminal device 100 generates grant information based on the received report information. In addition, the intra-office optical terminal device 100 evaluates the report value of the received report information and determines whether to send a report request and whether to send a first report request or a second report request.

For example, if the variation in the report value of the report information is not less than the variation standard, the first evaluation value i becomes 0. A first report request is sent to the in-home optical terminal device 20 whose first evaluation value i is 0. Further, if the variation in the report value of the report information is equal to or less than the variation standard, 1 is added to the first evaluation value i so that the first evaluation value i becomes 1 or more. A second report request is sent to the in-home optical terminal device 20 for which the first evaluation value i is 1 or more and the second evaluation value k is 1 or less.

A report request is not sent to the in-home optical terminal device 20 for which the first evaluation value i is 1 or more and the second evaluation value k is more than 1. Note that the second evaluation value k is first set to the first evaluation value i when the in-office optical termination device 100 receives the report information, and thereafter is subtracted by 1 each time the transmission of the report information is skipped. . Therefore, in order for the transmission of report information to be skipped, it is necessary for the intra-office optical terminal device 100 to receive report information in which the fluctuation of the report value is less than or equal to the fluctuation standard at least twice.

The grant information and report request are transmitted from the in-office optical terminal device 100 to each of the in-home optical terminal devices 20 in a Gate frame. Furthermore, in the Data Block, each of the in-home optical termination devices 20 transmits data to the in-office optical termination device 100 according to the band allocation (DBA cycle 1 in the figure).

In the next DBA cycle 2, each of the in-home optical termination devices 20 transmits report information to the in-office optical termination device 100 in accordance with the received report request. Specifically, the in-home optical terminal device 20 that has received the first report request transmits report information using a report block. Furthermore, the in-home optical terminal device 20 that has received the second report request transmits the report information in the band allocated in the Data Block, superimposing it on the data. Then, the in-home optical terminal device 20 that has not received the report request does not transmit report information.

Note that if the second evaluation value k exceeds 1 and no report request is sent, no report information will be sent in the next DBA cycle, so the in-office optical termination device 100 will not receive the report information from the in-home optical termination device 20. is not received, and the evaluation unit 122 subtracts 1 from the second evaluation value k. Therefore, the second evaluation value k will eventually become 1 or less and a second report request will be sent from the in-office optical termination device 100 to the in-home optical termination device 20, so that the data transmission time (Data Block) in the next DBA cycle will be Report information transmission will be resumed.

If the fluctuation of the report value is equal to or less than the fluctuation standard in the report information after restarting the transmission, 1 is further added to the first evaluation value i. The second evaluation value k is set to the same value as the first evaluation value i at this time. Therefore, the longer the fluctuation in the report value continues to be smaller than the fluctuation reference, the longer the report information transmission interval becomes. Then, when the fluctuation in the report value becomes larger than the fluctuation standard, 1 is subtracted from the first evaluation value i, so that the report information transmission interval becomes shorter. When the first evaluation value i finally decreases to 0, the report information is transmitted at the report transmission time (Report Block).

According to the above-described band control system, band control method, band control program, and in-home optical termination device 100, the in-home optical termination device 20 is evaluated based on report information received in the past, and the report value, that is, in-home optical termination device 20 is evaluated based on report information received in the past. If the fluctuation in the amount of traffic requested by the device 20 is small, the report information is transmitted superimposed with the data during the data transmission time within the DBA cycle. Further, if the report value, that is, the traffic amount requested by the in-home optical terminal device 20, is stable with small fluctuations, the transmission of the report information is skipped. Therefore, it is possible to narrow down the bandwidth required for report transmission within the DBA cycle, and to allocate that amount to the data transmission bandwidth, thereby improving bandwidth usage efficiency. In addition, when the transmission of report information is skipped, the report value is calculated based on the average traffic volume of report information received in the past. When the transmission of report information is skipped, fluctuations in the report value are small, so it is possible to perform band allocation with high accuracy based on the report value calculated in this way.

As a modification of the bandwidth control system, bandwidth control method, etc. according to this embodiment, the first evaluation value i may be set to 0 in step S23 of FIG. Therefore, in this modification, when the fluctuation of the report value becomes larger than the fluctuation standard, the first evaluation value i becomes 0 and the first report request is sent to the in-home optical terminal device 20, so that the report value is not reported in the next DBA cycle. Report information will be sent at the sending time.

The present disclosure can be used for a band control system, a band control method, a band control program, and an in-office optical termination device that are applied to a communication system that communicates optical signals between an in-office optical termination device and a plurality of in-home optical termination devices. .

1 Upstream external network 2 Downstream external network 10 Optical branching section 20 In-home optical termination device 100 In-office optical termination device 101 PON section 111 Report receiving section 112 DBA calculation section 113 Gate generation section 121 Report value determination section 122 Evaluation section 123 Report request Judgment section

Claims (6)

In a communication system that communicates optical signals between an in-office optical termination device and a plurality of in-home optical termination devices, the plurality of in-home optical termination devices transmit report information to the in-office optical termination device in accordance with a report request from the in-office optical termination device. The in-office optical termination device is a band control system that allocates a band for transmitting data from each of the plurality of in-home optical termination devices to the in-office optical termination device based on the report information. ,
The intra-office optical termination device is
a report value determination unit that determines a report value for each of the plurality of in-home optical terminal devices based on the report information received in the past;
Based on the report value determined by the report value determination unit, a band for transmitting data from each of the plurality of in-home optical termination devices to the in-office optical termination device is determined for each preset band allocation cycle. an allocation unit that allocates;
an evaluation unit that calculates an evaluation value for each of the plurality of in-home optical termination devices based on the report information received in the past;
a report request determination unit that determines whether or not to transmit the report request to each of the plurality of in-home optical terminal devices based on the evaluation value calculated by the evaluation unit;
When determining to transmit the report request, the report request determination unit divides the report request into a first report request that causes the report information to be transmitted at a report transmission time within the band allocation cycle, and a first report request that causes the report information to be transmitted at a report transmission time within the band allocation cycle. A bandwidth control system that determines either a second report request to transmit the report information at a data transmission time. The report request determination unit includes:
determining the report request as the first report request when the evaluation value corresponds to a case where a change in the report value of the report information is not less than a change standard;
The bandwidth control system according to claim 1, wherein the report request is determined to be the second report request when the evaluation value corresponds to a case where a change in the report value of the report information is equal to or less than the change standard. 2. The report request determination unit determines not to transmit the report request when the evaluation value corresponds to the case where the report information in which the fluctuation of the report value is equal to or less than the fluctuation standard is received at least twice. Bandwidth control system described in . In a communication system that communicates optical signals between an in-office optical termination device and a plurality of in-home optical termination devices, the plurality of in-home optical termination devices transmit report information to the in-office optical termination device in accordance with a report request from the in-office optical termination device. and the in-office optical termination device allocates a band for transmitting data from each of the plurality of in-home optical termination devices to the in-office optical termination device based on the report information, ,
a report value determining step of determining a report value for each of the plurality of in-home optical termination devices based on the report information received in the past by the in-office optical termination device;
Based on the report value determined in the report value determining step, a band for transmitting data from each of the plurality of in-home optical termination devices to the in-office optical termination device is determined for each preset band allocation cycle. an assignment step to allocate;
an evaluation step of calculating an evaluation value for each of the plurality of in-home optical termination devices based on the report information received in the past by the in-home optical termination device;
a report request determining step of determining whether or not to transmit the report request to each of the plurality of in-home optical terminal devices based on the evaluation value calculated in the evaluation step;
In the report request determination step, when it is determined to transmit the report request, the report request is divided into a first report request that causes the report information to be transmitted at a report transmission time within the band allocation cycle, and a first report request that causes the report information to be transmitted at a report transmission time within the band allocation cycle. A bandwidth control method comprising the step of determining either a second report request to transmit the report information at a data transmission time. In a communication system that communicates optical signals between an in-office optical termination device and a plurality of in-home optical termination devices, the plurality of in-home optical termination devices transmit report information to the in-office optical termination device in accordance with a report request from the in-office optical termination device. and the in-office optical terminating device operates a band control system that allocates a band when transmitting data from each of the plurality of in-home optical terminating devices to the in-office optical terminating device based on the report information. A bandwidth control program for
In the computer of the intra-office optical termination device,
a report value determining step of determining a report value for each of the plurality of in-home optical termination devices based on the report information received in the past by the in-office optical termination device;
Based on the report value determined in the report value determining step, a band for transmitting data from each of the plurality of in-home optical termination devices to the in-office optical termination device is determined for each preset band allocation cycle. an assignment step to allocate;
an evaluation step of calculating an evaluation value for each of the plurality of in-home optical termination devices based on the report information received in the past by the in-home optical termination device;
executing a report request determination step of determining whether or not to transmit the report request to each of the plurality of in-home optical terminal devices based on the evaluation value calculated in the evaluation step;
In the report request determination step, when it is determined to transmit the report request, the report request is divided into a first report request that causes the report information to be transmitted at a report transmission time within the band allocation cycle, and a first report request that causes the report information to be transmitted at a report transmission time within the band allocation cycle. A band control program including the step of determining either a second report request to transmit the report information at a data transmission time. An in-office optical termination device that allocates a band for transmitting data from each of the plurality of in-home optical termination devices based on report information transmitted from the plurality of in-home optical termination devices,
a report value determination unit that determines a report value for each of the plurality of in-home optical terminal devices based on the report information received in the past;
Based on the report value determined by the report value determination unit, a band for transmitting data from each of the plurality of in-home optical termination devices to the in-office optical termination device is determined for each preset band allocation cycle. an allocation unit that allocates;
an evaluation unit that calculates an evaluation value for each of the plurality of in-home optical termination devices based on the report information received in the past;
a report request determination unit that determines whether or not to transmit the report request to each of the plurality of in-home optical terminal devices based on the evaluation value calculated by the evaluation unit;
When determining to transmit the report request, the report request determination unit divides the report request into a first report request that causes the report information to be transmitted at a report transmission time within the band allocation cycle, and a first report request that causes the report information to be transmitted at a report transmission time within the band allocation cycle. and a second report request for transmitting the report information at a data transmission time.

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