JP2003087283A - Circuit, method and program for assigning dynamic band and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dynamically distribute an incoming band by contract band ratio of each request source with respect to the request source which requests band assignment when the incoming band is shared by a plurality of subscriber terminal units. SOLUTION: The subscriber terminal units 6, 7 and 8 transmits a buffer amount with an upper limit to station side communication equipment 25 at each request source as a band request signal. A dynamic band assigning circuit 30 in the station side communication equipment 25 receives the band request signal through the use of a band request receiving part 21. A band assignment calculating part 31 calculates a band assignment amount in response to the band request signal received within a fixed time for receiving the band request and also information of a cumulative value (excessive assignment band) in the already-assigned incoming band in an assignment band managing part 32. A transmission permission transmitting part 23 transmits an incoming data mount to be allowed for transmission and a transmission time to the service path terminal parts of the subscriber terminal units 6, 7 and 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a network system for connecting a plurality of subscriber terminating devices and a single station side communication device in a PON topology, and transmitting from the subscriber terminating device to the station side communication device. A dynamic band allocating circuit, a dynamic band allocating method, a dynamic band allocating program, and a recording medium that dynamically allocate a band according to a contracted band of a requester.

[0002]

2. Description of the Related Art Conventionally, when a band transmitted from a subscriber termination equipment value to a station side communication equipment value is shared by a plurality of subscriber termination devices or service paths, it is dynamically changed according to the contracted bandwidth of each request source. A method of allocating a band is known. The conventional method is a method of controlling a time for giving a band to each subscriber terminating device or each service path according to a contract band.

FIG. 5 is a block diagram showing the topology of a dynamic band allocation method according to the prior art. An optical fiber 3 connected to a dynamic band allocation circuit 2 of a single station-side communication device 1.
Is branched into a plurality of fibers 5a, 5b, 5c by the optical branching unit 4, and each of the fibers is connected to each subscriber terminating device 6, 7, 8. A single or a plurality of service path terminating units 9a and 9b are set in each subscriber terminating device 6, 7, and 8. Although FIG. 5 shows only the subscriber terminating device 6, other subscriber terminating devices 7 and 8 have the same configuration. The service path termination units 9a and 9b are connected to the request sources A and B, respectively, and the contract bandwidth can be set for each request source.

FIG. 6 is a block diagram showing the configuration of a dynamic band allocation circuit 2 according to the prior art. Subscriber termination device 6,
Each of 7 and 8 transmits a band request signal for each request source to the station side communication device 1. The band request signal for each request source transmitted by each subscriber terminating device 6, 7, 8 is received by the band request receiving unit 21, and is notified to the band allocation calculating unit 22. In the band allocation calculation unit 22, for the service path termination units corresponding to all request sources that have made band requests within a fixed time,
The transmission permission of the upstream signal is given for each time proportional to the guaranteed band, and the transmission permission transmission unit 23 causes each subscriber terminal device 6,
Send to 7 and 8.

[0005]

However, in the above-mentioned conventional technique, as shown in the frame configuration of FIG. 7, when packet data of variable length size is transmitted, the minimum unit for dividing the data is the packet size. , Data transmission time when transmission is permitted (uplink signal transmission permission time)
When the packet data in the buffer is sent to MSB just before, the packet being sent cannot be sent at the end of the data sending time,
As a result, an unallocated area having a maximum packet size is generated for each service path. Since this unallocated area differs for each allocation cycle, the bandwidth allocated to each service path is
This means that each guaranteed bandwidth is not accurately reflected.

The present invention has been made in view of the above-mentioned circumstances, and a dynamic band capable of dynamically distributing an upstream band to a requester requesting band allocation at a contracted band ratio of each requester. An object is to provide an allocation circuit, a dynamic band allocation method, a dynamic band allocation program, and a recording medium.

[0007]

In order to solve the above-mentioned problems, in the invention according to claim 1, a PON system in which a plurality of subscriber terminating devices and a single station side communication device are connected by a PON topology In the dynamic band allocation circuit provided in the station side communication device for distributing the upstream band of the plurality of subscriber terminal devices, the band request receiving means for receiving the band request amount from each of the plurality of subscriber terminal devices. And a request based on the allocated bandwidth management means for storing information on the bandwidth allocation amount allocated in the past for each request source, and the information on the bandwidth request amount for each request source and the cumulative value of the bandwidth allocation amount allocated in the past. A band allocation calculating unit for calculating the next band allocation amount for each element, and a transmission for transmitting a transmission permission based on the band allocation amount calculated by the band allocation calculating unit to each of the plurality of subscriber terminal devices. Characterized in that a granted transmission means.

According to the second aspect of the invention, the first aspect is
In the dynamic bandwidth allocation circuit described above, the allocation bandwidth management means stores an excess bandwidth allocation amount indicating an excess amount with respect to an ideal cumulative allocation amount as information regarding a cumulative value of the bandwidth allocation amount allocated in the past. Characterize.

In the invention according to claim 3, the invention according to claim 1
Alternatively, in the dynamic band allocation circuit according to the second aspect, a band measuring unit that measures an actual transmission data amount from each of the plurality of subscriber terminal devices for each request source, and an actual transmission measured by the band measuring unit. Based on the transmission data amount management unit that stores the data amount for each request source, and the previous actual transmission data amount and the previous band allocation amount stored in the transmission data amount management unit, the past allocation is performed. And a correction unit that corrects information about the cumulative value of the bandwidth allocation amount.

In order to solve the above problems,
In the invention described in claim 4, a PON in which a plurality of subscriber terminating devices and a single station-side communication device are connected by a PON topology
In a dynamic band allocation method for distributing upstream bands of a plurality of subscriber terminating devices of a system, a band request amount from each of the plurality of subscriber terminating devices is accepted, and a band request amount for each request source and past allocation The next band allocation amount is calculated for each requester based on the information on the accumulated value of the band allocation amount, and the transmission permission based on the next band allocation amount is transmitted to each of the plurality of subscriber terminal devices. It is characterized by

According to the invention of claim 5, claim 4 is
In the dynamic bandwidth allocation method described above, the information on the bandwidth allocation amount allocated in the past is an excess bandwidth allocation amount indicating an excess amount with respect to an ideal cumulative allocation amount.

Further, in the invention according to claim 6, the invention according to claim 4
Alternatively, in the dynamic bandwidth allocation method described in 5, the actual transmission data amount from each of the plurality of subscriber termination devices is measured for each request source, and the previous actual transmission data amount and the previous bandwidth allocation amount are calculated. Based on the above, the information on the cumulative value of the band allocation amount allocated in the past is corrected.

In order to solve the above problems,
According to the invention of claim 7, the step of accepting the bandwidth request amount from each of the plurality of subscriber terminal devices connected by the PON topology, and the accumulated value of the bandwidth request amount for each request source and the bandwidth allocation amount assigned in the past. To the computer, a step of calculating the next bandwidth allocation amount for each requester, and a step of transmitting a transmission permission based on the next bandwidth allocation amount to each of the plurality of subscriber terminal devices based on the information regarding It is characterized by being executed.

According to the invention of claim 8, claim 7 is provided.
In the dynamic bandwidth allocation program described, in the step of measuring the actual transmission data amount from each of the plurality of subscriber termination devices for each request source, the previous actual transmission data amount and the previous bandwidth allocation amount. Based on the above, the step of correcting the information regarding the cumulative value of the band allocation amount allocated in the past is executed by the computer.

In order to solve the above problems,
According to the invention of claim 9, the step of receiving the bandwidth request amount from each of the plurality of subscriber terminal devices connected by the PON topology, and the accumulated value of the bandwidth request amount for each request source and the bandwidth allocation amount assigned in the past. To the computer, a step of calculating the next bandwidth allocation amount for each requester, and a step of transmitting a transmission permission based on the next bandwidth allocation amount to each of the plurality of subscriber terminal devices based on the information regarding The feature is that the program to be executed is recorded.

According to the tenth aspect of the invention, in the recording medium of the ninth aspect, the step of measuring the actual amount of transmission data from each of the plurality of subscriber terminal devices for each request source, A program for causing a computer to execute the step of correcting the information regarding the cumulative value of the previously allocated bandwidth allocation amount based on the actual transmission data amount and the previous bandwidth allocation amount is recorded.

In the present invention, the next uplink data allocation amount is determined for each requesting source based on the cumulative value of the allocation data amount up to the previous time or the cumulative value of the transmission data amount up to the previous time.
Therefore, even when the packet data arriving at the subscriber terminal device has a variable length size, the upstream band can be distributed at the contracted bandwidth ratio of each service path.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. A. First Embodiment A-1. Configuration of First Embodiment FIG. 1 is a block diagram showing the configuration of a PON system according to the first embodiment of the present invention. Note that the portions corresponding to those in FIG. In FIG. 1, the dynamic band allocation circuit 30 of the station-side communication device 25 includes a band request reception unit 21, a transmission permission transmission unit 23, a band allocation calculation unit 31, and an allocation band management unit 32. The band allocation calculating unit 31 determines the band allocation amount according to the band request signal received by the band request receiving unit 21 within the band request receiving time of a fixed time and the accumulated value information of the upstream band already allocated in the allocation band management unit 33. And the scheduling of the allocation order. The allocated bandwidth management unit 32 manages, for each request source, an excessive allocated bandwidth that indicates an excessive amount with respect to the ideal cumulative allocated amount, as cumulative value information of the allocated upstream bandwidth. The bandwidth request receiver 21, the transmission permission transmitter 23, the bandwidth allocation calculator 31, and the allocated bandwidth manager 32.
Each unit of the above periodically repeats the above series of operations.

A-2. Operation of First Embodiment Next, the operation of the above-described first embodiment will be described in detail. The data transmitted from the request source to the subscriber terminating devices 6, 7, and 8 are in the respective service path termination units,
It is stored in a buffer (not shown). Subscriber termination device 6,
From 7, 8 the upper limit buffer amount for each request source is transmitted to the station side communication device 25 as a band request signal. In the dynamic band allocation circuit 30 of the station side communication device 25, the band request receiving unit 21 receives the band request signal and supplies it to the band allocation calculating unit 31. In addition, information on the already accumulated uplink cumulative band in the allocated band management unit 32 is the band allocation calculation unit 3
1 is supplied. The band allocation calculation unit 31 calculates the band allocation amount according to the band request signal received within the band request reception time of a certain time and the already allocated uplink cumulative band information in the allocation band management unit 32 and The order is scheduled. Then, the transmission permission transmission unit 23 transmits the amount of uplink data and transmission time at which transmission is permitted to the service path termination units of the subscriber termination devices 6, 7, and 8. These series of operations are periodically repeated.

Here, an example of a method of determining the band allocation amount in the band allocation calculation unit 31 will be described. Figure 2
7 is a flowchart showing an algorithm of a method for determining a bandwidth allocation amount by the bandwidth allocation calculating unit 31 according to the first embodiment. In the figure, j is the ONU number, k is the period, and bw_
temp _{j, k} is the allocated bandwidth, bw_real _{j, k} is the actual data transmission amount, bw_ideal _{j, k} is the ideal bandwidth, bw_
add _{j, k} is an over-allocated band, bw_ref is an ideal total allocated band, bw_min _j is a guaranteed band, and Q _{j, k} is a requested band.

First, the total of the ideal allocation bandwidths to each request source in one cycle (k = 1) is set as the ideal total allocation bandwidth. First, the ideal total allocation bandwidth is calculated between the requesters requesting the bandwidth in the first cycle. Proportional distribution is made in each requesting contract band, and this is set as an ideal band bw_ideal _{j, k} of the first cycle (step S1). If the ideal bandwidth bw_ideal _{j, k} is positive, the allocated bandwidth bw_
Let temp _{j, k} be the requested bandwidth Q _{j, k,} and allow transmission of the requested bandwidth Q _{j, k} (steps S2, S3). On the other hand, if the ideal bandwidth bw_ideal _{j, k} is 0 or less, the allocated bandwidth bw_
The temp _{j, k is set} to 0 and the transmission permission is not given (steps S2 and S4). Next, the difference between the allocated bandwidth bw_temp _{j, k} and the ideal bandwidth bw_ideal _{j, k} is calculated (step S5), and the excess allocated bandwidth bw_add _{j, k} is stored in the allocated bandwidth management unit 32 for each request source.

In the second and subsequent cycles (k> 1), when the ideal bandwidth bw_ideal _{j, k} is calculated, the value of the ideal total allocation bandwidth is proportionally distributed to the previous excess allocation bandwidth bw_ad.
The value obtained by subtracting d _{j, k-1} is the ideal band bw_ of the period.
ideal _{j, k} (step S1), the allocated bandwidth bw_temp _{j, k} is determined in the same procedure as the first cycle (steps S2, S3, S4), and the excess allocated bandwidth bw_add _{j, k is determined.}
After calculating, the bandwidth management unit 32 stores the request for each request source. In the subscriber terminal devices 6, 7, and 8, the allocated bandwidth bw_
In accordance with temp _{j, k} , the uplink data for the allocated band is transmitted. In this way, by repeating the above steps for each cycle (step S6), the cumulative value of the allocated bandwidth bw_temp _{j, k} can be distributed at the guaranteed bandwidth ratio for each requester.

B. Second embodiment B-1. Configuration of Second Embodiment Next, a second embodiment of the present invention will be described. Book second
In the embodiment, since the bandwidth allocated to each request source and the amount of uplink data actually transmitted by the request source are different, the actual transmission data amount is counted for each request source, and the allocated bandwidth and the actual transmission data are counted. The difference from the amount is reflected in the calculation of the over-allocated band in the next period and thereafter.

FIG. 3 shows a PO according to the second embodiment of the present invention.
It is a block diagram which shows the structure of N system. In the figure, the upstream band measurement unit 40 counts the actual transmission data amount for each request source. The band allocation calculation unit 41 calculates the band allocation amount, schedules the allocation order, and
The excess allocated band in the next period and thereafter is calculated according to the difference between the allocated band and the actual transmission data amount measured by the upstream band measuring unit 40. The transmission data amount management unit 42 manages the actual transmission data amount measured by the upstream band measurement unit 40 for each request source.

B-2. Operation of Second Embodiment Next, the operation of the above-described second embodiment will be described.
The data transmitted from the request source to the subscriber terminating devices 6, 7 and 8 are stored in buffers (not shown) at the respective service path termination units. From the subscriber terminating devices 6, 7, and 8, the upper limit buffer amount is transmitted to the station side communication device 25 as a band request signal for each request source. Station side communication device 25
In the dynamic band allocation circuit 30, the band request reception unit 21 receives the band request signal, and the band allocation calculation unit 41
In addition to being supplied to the bandwidth allocation calculation unit 41, the upstream bandwidth measurement unit 40 counts the actual transmission data amount for each request source. Further, the transmission data amount management unit 42
The amount of transmission data within is supplied to the band allocation calculation unit 41.
In the band allocation calculation unit 41, the band allocation amount is calculated, the allocation order is scheduled, and the excess allocation band after the next cycle is calculated according to the difference between the allocation band and the actual transmission data amount. Then, the transmission permission transmission unit 23 transmits the amount of uplink data and transmission time at which transmission is permitted to the service path termination units of the subscriber termination devices 6, 7, and 8. These series of operations are periodically repeated.

Here, an example of a method of determining the bandwidth allocation amount in the bandwidth allocation calculation unit 41 will be described. Figure 4
11 is a flowchart showing an algorithm of a method for determining a bandwidth allocation amount by a bandwidth allocation calculating unit 41 according to the second embodiment. In the figure, the meaning of each symbol is the same as in FIG.

First, the sum of the ideal allocation bandwidths to each request source in one cycle (k = 1) is set as the ideal total allocation bandwidth, and first, the ideal total allocation bandwidth is calculated between the requesters requesting the bandwidth in the first cycle. Proportional distribution is made in each requesting contract band, and this is set as an ideal band bw_ideal _{j, k} of the first cycle (step S11). If the ideal bandwidth bw_ideal _{j, k} is positive, the allocated bandwidth bw
_Temp _{j, k} is the requested bandwidth Q _{j, k,} and transmission permission for the requested bandwidth Q _{j, k} is given (steps S12, S13). On the other hand, if the ideal bandwidth bw_ideal _{j, k} is 0 or less, the allocated bandwidth bw_temp _{j , k is set} to 0, and transmission permission is not given (steps S12 and S14). Next, the allocated bandwidth bw_te
The difference between the mp _{j, k} and the ideal bandwidth bw_ideal _{j, k} is calculated as the over-allocated bandwidth bw_add _{j, k} and stored in the transmission data amount management unit 42 for each request source (step S1).
6).

In the second and subsequent cycles (k> 1), when the ideal bandwidth bw_ideal _{j, k} is calculated, the value of the ideal total allocation bandwidth is proportionally distributed to the previous excess allocation bandwidth bw_ad.
The value obtained by subtracting d _{j, k-1} is the ideal band bw_ of the period.
It is set to ideal _{j, k} (step S11), and the allocated bandwidth bw_temp _{j, k} is determined by the same procedure as in the first cycle (steps S12, S13, S14). Next, it is judged whether or not the amount of upstream data transmission bw_real _{j, k-1} actually transmitted last time is the same as the upstream bandwidth bw_temp _{j, k-1} allocated last time (step S15), and both are the same. Then, as in the first embodiment, the excess allocation bandwidth bw
After calculating _add _{j, k} , it is stored in the transmission data amount management unit 42 for each request source (step S16).

On the other hand, when the amount of upstream data transmission bw_real _{j, k-1} actually transmitted last time is different from the upstream band bw_temp _{j, k-1} assigned last time, a value obtained by subtracting the former from the latter (bw_real _{j, k-1} -bw_t
emp _{j, k-1} ) for the next and subsequent over-allocated bandwidth (bw_re
al _{j, k} −bw_temp _{j, k} ) to calculate the over-allocated bandwidth bw_add _{j, k,} which is then stored in the transmission data amount management unit 42 for each request source (step S17). In this way, by repeating the above-mentioned steps for each cycle (step S18), the allocated bandwidth bw_temp
It is possible to distribute the cumulative value of _{j, k} at the guaranteed bandwidth ratio for each request source.

In the first and second embodiments described above, the function of the dynamic band allocation circuit 30 of the station side communication device 25 is realized by executing a program stored in a storage unit (not shown). Has become. The storage unit is a hard disk device, a magneto-optical disk device, a nonvolatile memory such as a flash memory, or a RAM (Random Access Memory).
Such a volatile memory or a combination thereof. Further, the storage unit is
Some hold a program for a certain period of time, such as volatile memory (RAM) inside a computer system that serves as a server or a client when the program is sent via a network such as the Internet or a communication line such as a telephone line. Including.

Further, the above program may be transmitted from a computer system in which the program is stored in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the "transmission medium" for transmitting the program refers to a medium having a function of transmitting information, such as a network such as the Internet or a communication line such as a telephone line. Also,
The above-mentioned program may be for realizing a part of the above-mentioned processing. Further, it may be a so-called difference file (difference program) that can realize the above-mentioned processing in combination with the program already recorded in the station side communication device 25 or the dynamic band allocation circuit 30.

Although the embodiments of the present invention have been described in detail above with reference to the drawings, the specific configuration is not limited to the above-mentioned embodiments, and a design etc. within a range not departing from the gist of the present invention are also possible. included.

[0033]

As described above, according to the present invention,
In the PON system, the next uplink data allocation amount is determined based on the cumulative value of the past allocation data amount or the cumulative value of the past transmission data amount for each requesting source, so that it arrives at the subscriber terminal device. Even when the packet data has a variable length size, there is an advantage that the upstream band can be distributed at the contracted bandwidth ratio of each service path. Since this is done, the advantage is obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a PON system according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing an algorithm of a band allocation amount determination method by a band allocation calculation unit 31 according to the first embodiment.

FIG. 3 is a block diagram showing a configuration of a PON system according to a second embodiment of the present invention.

FIG. 4 is a flowchart showing an algorithm of a method of determining a bandwidth allocation amount by a bandwidth allocation calculating unit 41 according to the second embodiment.

FIG. 5 is a block diagram showing a topology of a dynamic band allocation method according to a conventional technique.

FIG. 6 is a block diagram showing a configuration of a station side communication device 1 according to a conventional technique.

FIG. 7 is a conceptual diagram showing a frame structure of a conventional system.

[Explanation of symbols]

6, 7 and 8 Subscriber terminating devices 9a and 9b Service path terminating unit 21 Band request receiving unit (band request receiving unit) 23 Transmission permission transmitting unit (Transmission permission transmitting unit) 25 Station side communication device 30 Dynamic band allocation circuit 31 , 41 band allocation calculation unit (band allocation calculation unit, correction unit) 32 allocation band management unit (allocation band management unit) 40 upstream band measurement unit (band measurement unit) 42 transmission data amount management unit (transmission data amount management unit)

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Claims (10)

[Claims] 1. A station-side communication device of a PON system in which a plurality of subscriber-termination devices and a single station-side communication device are connected by a PON topology is provided, and an upstream band of the plurality of subscriber-termination devices is distributed. In the dynamic bandwidth allocating circuit, a bandwidth request receiving unit that receives a bandwidth request amount from each of the plurality of subscriber terminating devices, and an allocation bandwidth managing unit that stores information regarding a bandwidth allocation amount that has been assigned in the past for each request source. A bandwidth allocation calculation means for calculating the next bandwidth allocation amount for each request source based on the bandwidth request amount for each request source and the information about the cumulative value of the bandwidth allocation amount assigned in the past; And a transmission permission transmitting means for transmitting a transmission permission based on the bandwidth allocation amount calculated by the above to each of the plurality of subscriber terminal devices. 2. The allocated bandwidth management means stores an excess bandwidth allocation amount indicating an excess amount with respect to an ideal cumulative allocation amount, as information on a cumulative value of the bandwidth allocation amount allocated in the past. Item 1. The dynamic band allocation circuit according to item 1. 3. Bandwidth measuring means for measuring an actual transmission data amount from each of the plurality of subscriber terminal devices for each request source, and an actual transmission data amount measured by the band measurement means for each request source. Based on the previous actual transmission data amount and the previous bandwidth allocation amount stored in the transmission data amount management means, the cumulative value of the previously allocated bandwidth allocation amount. And a correction unit that corrects information regarding the information.
Alternatively, the dynamic band allocation circuit described in 2. 4. A dynamic band allocation method for distributing an upstream band of a plurality of subscriber terminating devices of a PON system in which a plurality of subscriber terminating devices and a single station-side communication device are connected in a PON topology, The bandwidth request amount from each of the plurality of subscriber terminal devices is accepted, and the next bandwidth allocation is performed for each request source based on the bandwidth request amount for each request source and the information on the cumulative value of the bandwidth allocation amount assigned in the past. A dynamic bandwidth allocation method comprising: calculating an amount and transmitting a transmission permission based on the next bandwidth allocation amount to each of the plurality of subscriber terminal devices. 5. The dynamic bandwidth allocation method according to claim 4, wherein the information on the bandwidth allocation amount allocated in the past is an excess bandwidth allocation amount indicating an excess amount with respect to an ideal cumulative allocation amount. 6. The actual transmission data amount from each of the plurality of subscriber terminal devices is measured for each request source, and based on the previous actual transmission data amount and the previous bandwidth allocation amount, the past The dynamic band allocation method according to claim 4 or 5, wherein the information on the cumulative value of the allocated band allocation amount is corrected. 7. A step of receiving a bandwidth request amount from each of a plurality of subscriber termination devices connected by a PON topology, and information on a bandwidth request amount for each request source and a cumulative value of the bandwidth allocation amount assigned in the past. And causing the computer to execute the step of calculating the next bandwidth allocation amount for each requester, and the step of transmitting a transmission permission based on the next bandwidth allocation amount to each of the plurality of subscriber termination devices. A dynamic bandwidth allocation program characterized by: 8. A step of measuring an actual transmission data amount from each of the plurality of subscriber terminating devices for each requesting source, based on a previous actual transmission data amount and a previous bandwidth allocation amount. 8. The dynamic bandwidth allocation program according to claim 7, further comprising: a step of correcting information regarding a cumulative value of the bandwidth allocation amount allocated in the past. 9. A step of receiving a bandwidth request amount from each of a plurality of subscriber terminating devices connected in a PON topology, and information on a bandwidth request amount for each request source and a cumulative value of the bandwidth allocation amount assigned in the past. A program for causing a computer to execute a step of calculating a next bandwidth allocation amount for each requester based on the above, and a step of transmitting a transmission permission based on the next bandwidth allocation amount to each of the plurality of subscriber terminal devices. A recording medium on which is recorded. 10. A step of measuring an actual transmission data amount from each of the plurality of subscriber terminal devices for each request source, and based on a previous actual transmission data amount and a previous bandwidth allocation amount. 10. The recording medium according to claim 9, wherein a program for causing a computer to execute the step of correcting the information regarding the cumulative value of the bandwidth allocation amount allocated in the past is recorded.