JP2007335986A - Communication apparatus and communication method - Google Patents

Abstract

Provided is a communication device and a communication method capable of maintaining high communication efficiency even when it is necessary to process many frames with low priority levels for data transfer.
When traffic of a frame with a priority level equal to or higher than a predetermined level is not detected, a setting is made to increase the traffic of a frame with a priority level lower than the predetermined level.
[Selection] Figure 5

Description

  The present invention relates to a communication apparatus and a communication method, and more particularly to a communication apparatus and a communication method for performing data communication using an optical fiber.

  With the diversification of Internet services, there is an increasing need to transmit a plurality of frames having different data transfer priority levels on the same physical medium. Therefore, a communication system using a PON (Passive Optical Network) (hereinafter also referred to as a PON communication system) is becoming widespread.

  The PON communication system is a system in which a plurality of ONUs (Optical Network Units) are connected to an OLT (Optical Line Terminal) via optical fibers. Therefore, when the OLT and each of the plurality of ONUs perform data communication, a limited transmission path must be shared. Therefore, in the PON communication system, efficient use of a shared transmission path is required.

  Therefore, in Japanese Patent Application Laid-Open No. 2004-343734 (Patent Document 1), in the PON communication system, a technique for efficiently using a transmission path by minimizing frame delay (hereinafter also referred to as the first prior art). Say).

  Japanese Patent Laid-Open No. 2003-087281 (Patent Document 2) discloses a technique for efficiently using a transmission line by performing appropriate bandwidth allocation in a PON communication system (hereinafter also referred to as second prior art). Is disclosed.

  In addition, as described above, network devices having a scheduler function for performing transmission / reception scheduling of each flow while supporting an SLA (Service Level Agreement) have appeared along with an increase in necessity of transmitting a plurality of traffics. Here, SLA is the communication service quality such as the minimum communication speed of the line, the minimum guaranteed bandwidth of the line, the maximum allowable bandwidth of the line, the maximum delay time of the communication system, the average delay time in the network, and the upper limit of the unavailable time. Is specified.

  A WRR (Weighted-Round-Robin) type scheduler is widely used as the scheduler function. The network device having the scheduler function described above supports SLA on a flow basis by the WRR scheduler.

Japanese Patent Laid-Open No. 11-017690 (Patent Document 3) discloses a technique using the WRR method (hereinafter also referred to as a third prior art).
JP 2004-343734 A JP 2003-087281 A JP-A-11-017690

  Recently, a PON communication system in which the third prior art is applied to the first or second prior art is common. However, in such a PON communication system, the minimum guaranteed bandwidth and the maximum allowable bandwidth are set to fixed values so as to support SLA for each of a plurality of frames having different data transfer priority levels.

  In a situation where data communication is performed using a plurality of frames with different data transfer priority levels, the minimum guaranteed bandwidth and the maximum allowable bandwidth are generally set lower for frames with lower data transfer priority levels.

  Therefore, there is a problem that communication efficiency is greatly reduced when a communication state in which many frames with low priority levels for data transfer need to be processed.

  The present invention has been made to solve the above-described problems, and its purpose is to maintain high communication efficiency even when it is necessary to process many frames with low priority levels for data transfer. It is to provide a communication device capable of performing the above.

  Another object of the present invention is to provide a communication method capable of maintaining high communication efficiency even when it is necessary to process many frames with low priority levels for data transfer.

  In order to solve the above-described problem, a communication device according to an aspect of the present invention monitors a traffic of a reception unit that receives a frame and a plurality of frames that are received by the reception unit and that have different data transfer priority levels. If the monitoring means, the transmission means for transmitting the received frame based on the value of the predetermined parameter, and the monitoring means do not detect the traffic of the frame having the priority level higher than the predetermined level, the value of the predetermined parameter is set to the predetermined value. Setting means for setting to another value for increasing the traffic of a frame having a priority level lower than the level.

  According to the present invention, when the traffic of a frame having a priority level equal to or higher than a predetermined level is not detected, the setting for increasing the traffic of a frame having a priority level lower than the predetermined level is performed.

  Therefore, even when it is necessary to process many frames with low priority levels for data transfer, there is an effect that high communication efficiency can be maintained.

  Preferably, the value of the predetermined parameter is a value restricted by a predetermined communication service quality rule, and the other value set by the setting means relaxes the value restricted by the predetermined communication service quality rule. Value.

  According to the present invention, the other value for increasing the traffic of the priority level frame lower than the predetermined level is a value that relaxes the value restricted by the predetermined communication service quality rule. Therefore, since the value restricted by the communication service quality rule is relaxed, there is an effect that high communication efficiency can be maintained.

  Preferably, the priority level less than the predetermined level includes a first level and a second level lower than the first level, and the communication device further includes storage means for storing the received frame, and the other values are: A value for increasing the maximum allowable bandwidth at the time of transmission of the second level frame, a value for decreasing the maximum allowable bandwidth at the time of transmission of the first level frame, and a maximum allowable bandwidth at the time of transmission of the second level frame Is replaced with the maximum allowable bandwidth at the time of transmission of the first level frame, and at least one value for increasing the number of second level frames that the transmission means continuously reads from the storage means and transmits Meet.

  According to the present invention, the processing for increasing the maximum allowable bandwidth at the time of transmitting the second level frame, the processing for decreasing the maximum allowable bandwidth at the time of transmitting the first level frame, and the maximum at the time of transmitting the second level frame At least one process of replacing the allowable band with the maximum allowable band at the time of transmission of the first level frame and increasing the number of second level frames to be continuously read and transmitted is performed.

  Therefore, it is possible to efficiently process the second level frame lower than the first level included in the priority level less than the predetermined level. As a result, it is possible to maintain high communication efficiency even when it is necessary to process many frames with low priority levels for data transfer.

  According to another aspect of the present invention, there is provided a communication method performed by a communication apparatus, wherein a reception step of receiving a frame and a traffic of each of a plurality of frames received by the reception step and having different data transfer priority levels are monitored. A monitoring step, a transmission step of transmitting a received frame based on a value of a predetermined parameter, and a monitoring step when a traffic of a frame having a priority level equal to or higher than a predetermined level is not detected. A setting step for setting to another value for increasing the traffic of a frame having a priority level lower than the level.

  According to the present invention, when the traffic of a frame having a priority level equal to or higher than a predetermined level is not detected, the setting for increasing the traffic of a frame having a priority level lower than the predetermined level is performed.

  Therefore, even when it is necessary to process many frames with low priority levels for data transfer, there is an effect that high communication efficiency can be maintained.

  The communication apparatus according to the present invention performs setting for increasing the traffic of frames having a priority level lower than a predetermined level when the traffic of frames having a priority level higher than a predetermined level is not detected.

  Therefore, even when it is necessary to process many frames with low priority levels for data transfer, there is an effect that high communication efficiency can be maintained.

  The communication method according to the present invention is configured to increase the traffic of frames having a priority level lower than a predetermined level when no traffic of frames having a priority level higher than a predetermined level is detected.

  Therefore, even when it is necessary to process many frames with low priority levels for data transfer, there is an effect that high communication efficiency can be maintained.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

<First Embodiment>
FIG. 1 is a diagram showing a configuration of a communication system 10000 in the present embodiment. The communication system 10000 is, for example, the above-described PON communication system. The PON communication system is assumed to be a system based on GE (Gigabit Ethernet (registered trademark))-PON, for example. The PON communication system is not limited to GE-PON, and may be B (Broadband) -PON using ATM (Asynchronous Transfer Mode), for example.

  Referring to FIG. 1, a communication system 10000 includes an OLT 1000, ONUs 200.1, 200.2, 200.3, and an optical coupler 300. The number of ONUs is not limited to three and may be four or more.

  The ONU 200.1, 200.2, 200.3 and the OLT 1000 are devices based on, for example, the IEEE 802.3ah standard 1000BASE-PX10 standard. The ONUs 200.1, 200.2, 200.3 and the optical coupler 300 are connected by an optical fiber cable that is a transmission path.

  The ONUs 200.1, 200.2, and 200.3 are connected to PCs (Personal Computers) 210.1, 210.2, and 210.3, respectively. The number of PCs connected to each of the ONUs 200.1, 200.2, 200.3 is not limited to one, and a plurality of PCs may be used. The devices connected to each of the ONUs 200.1, 200.2, and 200.3 are not limited to PCs, but are dedicated terminals such as set-top boxes and IP telephone adapters, and routers that bundle them. Also good.

  The optical coupler 300 and the OLT 1000 are connected by an optical fiber cable that is a transmission path. The OLT 1000 is connected to the server 50. Server 50 is, for example, a PC.

  Communication system 1000 is not limited to the configuration described above. For example, one ONU and one OLT may be connected by an optical fiber cable without using an optical coupler.

  Hereinafter, each of a plurality of paths through which data (hereinafter also referred to as frames) between the OLT 1000 and the ONUs 200.1, 200.2, and 200.3 is also referred to as a logical path (channel). In the following, data exchanged between the OLT 1000 and each of the ONUs 200.1, 200.2, and 200.3 is also referred to as a frame. The OLT 1000 performs data communication via a logical path formed between a terminal device to be communicated among the ONUs 200.1, 200.2, and 200.3 and the OLT 1000. In the following, OLT1000 and ONU200. A logical path between m (m: natural number) is expressed as a logical path m. For example, the logical path between the OLT 1000 and the ONU 200.1 is the logical path 1.

  In the following, ONUs 200.1, 200.2, and 200.3 are also collectively referred to as ONU200. Hereinafter, a logical path between the OLT 1000 and one ONU 200 is also referred to as a logical path A. In the following, the direction in which a frame is transmitted from the ONU 200 to the OLT 1000 is also referred to as an uplink direction. The direction in which a frame is transmitted from the OLT 1000 to the ONU 200 is also referred to as a downlink direction.

  FIG. 2 is a block diagram showing an example of the internal configuration of the OLT 1000. As shown in FIG. Referring to FIG. 2, OLT 1000 includes a data transmission unit 1100 and a data transmission unit 1300.

  The data transmission unit 1100 has a function of processing a frame transmitted in the uplink direction. The data transmission unit 1300 has a function of processing a frame transmitted in the downlink direction.

  FIG. 3 is a diagram showing the structure of the frame. Referring to FIG. 3, the frame includes an Ethernet (registered trademark) header part, an IP (Internet Protocol) datagram, and an FCS (Frame Check Sequence) part. The Ethernet (registered trademark) header part is a part in which DA (destination Address), SA (Source Address), and the like are described. DA is the destination address of the frame. SA is the source address of the frame. DA and SA are MAC addresses. The FCS part is a part where there is a description used for frame error detection.

  The IP datagram is composed of an IP (Internet Protocol) header part and a TCP segment part. The IP header portion is a portion in which a TOS (Type of Service) field, an IP datagram destination, an IP datagram transmission source IP (Internet Protocol) address, and the like are described. A TOS (Type of Service) field describes the priority of frame transfer. The priority is described by a value in the range of “0” to “7”, and the higher the value, the higher the priority. That is, when the priority described in the TOS field is “7”, the priority for transferring the frame is the highest. On the other hand, when the priority described in the TOS field is “0”, the priority for transferring the frame is the lowest.

  In the following, frames with a priority of “0” to “2” are also referred to as low priority frames. For example, frames with a priority of “3” to “5” are also referred to as medium priority frames. Further, for example, frames having a priority of “6” to “7” are also referred to as high priority frames. The priorities of the low priority frame, the medium priority frame, and the high priority frame are not limited to the above. Therefore, the priority of each of the low priority frame, the medium priority frame, and the high priority frame may be another value.

  A low-priority frame is a frame with low importance of reception timing. That is, the low priority frame is a frame that does not cause a problem even if the reception timing is somewhat delayed. The low priority frame is, for example, a data frame of a web page. The high priority frame is data in which real-time property is required for reception timing and the importance of reception timing is high. The high priority frame is, for example, a frame used in an IP phone, a frame of streaming video, or the like. The medium priority frame is a frame in which the importance of reception timing is about the middle between the low priority frame and the high priority frame.

  The TCP segment part is composed of a TCP header part and a data part. In the TCP header part, header information based on the TCP protocol is described. The data part is a part where the content of data is described.

  Referring to FIG. 2 again, data transmission unit 1100 includes a reception unit 1110 and a classification unit 1120. The receiving unit 1110 receives a frame (data) from the optical coupler 300. The receiving unit 1110 converts the frame as an optical signal received from the optical coupler 300 into electrical digital data, and transmits the electrical digital data to the classification unit 1120.

The OLT 1000 further includes a control unit 1400 and a storage unit 1500.
The control unit 1400 has a function of controlling each unit in the OLT 1000. The control unit 1400 may be any of a microprocessor, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), and other circuits having arithmetic functions.

  The storage unit 1500 has a function of storing data in a nonvolatile manner. The storage unit 1500 is accessed by the control unit 1400. Storage unit 1500 is, for example, a medium (for example, a flash memory) that can hold data in a nonvolatile manner even when power is not supplied.

  Data transmission unit 1100 further includes a storage unit 1130. The storage unit 1130 includes queues 1131, 1132, and 1133. Here, the queue is a storage location for storing data (frames) provided in the storage unit 1130. Note that the number of queues in the storage unit 1130 may be four or more. The queues 1131, 1132, and 1133 in the storage unit 1130 have higher priority in the order of the queues 1133, 1132, and 1131, for example. That is, frames with high priority are stored in the order of queues 1133, 1132 and 1131.

  The plurality of queues are not limited to higher priority in the order of the queues 1133, 1132 and 1131. For example, the priority may increase in the order of the queues 1131, 1132, and 1133.

Control unit 1400 further sets classification unit 1120.
The classification unit 1120 classifies received frames based on the settings of the control unit 1400. The setting of the classification unit 1120 is, for example, a setting in which queue the classification unit 1120 stores frames based on the priority of received frames.

  Specifically, the classification unit 1120 stores the received frame in a queue in the storage unit 1130 according to the priority of the received frame, for example, the TOS field, based on the setting of the control unit 1400. For example, when the priority of the TOS field of the received frame is “7”, the classification unit 1120 stores the received frame (high priority frame) in the queue 1131 in the storage unit 1130. The classification unit 1120 stores the high priority frame, the medium priority frame, and the low priority frame in the queues 1131, 1132, and 1133, respectively.

  The control unit 1400 also performs processing for monitoring a frame received by the classification unit 1120, as will be described in detail later.

  Data transmission unit 1100 further includes a scheduler unit 1140. The scheduler unit 1140 is a scheduler that operates based on a WRR (Weighted-Round-Robin) method. The storage unit 1500 stores a reference setting data table in advance. The control unit 1400 further sets various parameters of the scheduler unit 1140 based on the reference setting data table read from the storage unit 1500. The various parameters include a weight, a minimum guaranteed bandwidth, a maximum allowable bandwidth, and the like in the uplink direction, which will be described later.

  The reference setting data table is a data table when assuming a communication state in which the classification unit 1120 receives at least one of the high priority frame, the medium priority frame, and the low priority frame. The reference setting data table is a data table when the classification unit 1120 assumes a communication state in which each of the high priority frame, the medium priority frame, and the low priority frame is received without a large deviation. The reference setting data table is, for example, the following reference setting data table T100.

  FIG. 4 is a diagram illustrating a setting data table as an example. FIG. 4A is a diagram illustrating a reference setting data table T100 as an example. Referring to FIG. 4A, reference setting data table T100 includes a plurality of frame setting data. In the reference setting data table T100, “number” is a number for managing a plurality of frame setting data. The “priority level” is a priority level for transmitting a frame.

  In the present embodiment, it is assumed that the priority levels of the high priority frame, the medium priority frame, and the low priority frame are the H, M, and L levels, respectively. In the following, the three queues in which frames having priority levels of H, M, and L are stored are also referred to as queues of H, M, and L levels, respectively. For example, a queue 1131 in which a high priority frame with a priority level of H level is stored is a queue with a priority level of H level. Therefore, the priority levels of the queues 1131, 1132, and 1133 are the H, M, and L levels, respectively.

  “Up” in the “direction” item indicates that the direction in which the corresponding frame is transmitted is the up direction. “Downlink” in the “Direction” item indicates that the transmission direction of the corresponding frame is the downlink direction.

  The “minimum guaranteed bandwidth” and the “maximum allowable bandwidth” are set to support SLA (Service Level Agreement). Here, the SLA is a regulation of service quality of communication. That is, the “minimum guaranteed bandwidth” and the “maximum allowable bandwidth” are values limited by the SLA.

  The “minimum guaranteed bandwidth” is a bandwidth that is guaranteed to transmit a frame (data) in a bandwidth that is equal to or greater than a corresponding numerical value. For example, when the minimum guaranteed bandwidth in the uplink direction is 10 Mbps (bit per second), the uplink frame is transmitted at 10 Mbps or more.

  The “maximum permissible bandwidth” is a bandwidth that is allowed to transmit a frame (data) in a bandwidth that is equal to or less than a corresponding numerical value. For example, when the maximum allowable bandwidth in the uplink direction is 1000 Mbps (bit per second), the uplink frame is transmitted in a bandwidth of 1000 Mbps or less.

  The “weight” is the maximum number of frames that the scheduler unit continuously reads from a certain queue at a time. For example, when five high priority frames are stored in the queue 1131 in which high priority frames having a priority level of H level are stored, the scheduler unit 1140 can continuously store a maximum of four from the queue 1131 at a time. Read the high priority frame. Note that the definition of “weight” is not limited to the above definition. For example, the “weight” may be the maximum frame (data) size that the scheduler unit continuously reads from the queue at a time.

Referring to FIG. 2 again, data transmission unit 1100 further includes a transmission unit 1150.
The transmission unit 1150 receives the frame transmitted from the scheduler unit 1140 and transmits the received frame to the server 50.

  The scheduler unit 1140 performs processing for sequentially reading frames by the weight of the corresponding priority level in the order from the queue with the highest priority to the queue with the lower priority.

  Here, the minimum guaranteed bandwidth, the maximum allowable bandwidth, and the weight in the uplink H level frame (queue), which are various parameters of the scheduler unit 1140 set based on the reference setting data table T100, are 10 Mbps, 1000 Mbps, 4 pieces. Further, the minimum guaranteed bandwidth, the maximum allowable bandwidth, and the weight in the M-level frame (queue) in the uplink direction, which are various parameters of the scheduler unit 1140 set based on the reference setting data table T100, are 5 Mbps and 900 Mbps, respectively. , Will be three. Also, the minimum guaranteed bandwidth, the maximum allowable bandwidth and the weight in the L-level frame (queue) in the uplink direction, which are various parameters of the scheduler unit 1140 set based on the reference setting data table T100, are 1 Mbps and 800 Mbps, respectively. , One.

  The scheduler unit 1140 set based on the reference setting data table T100 performs, for example, the following processing.

  When five medium priority frames in the uplink direction are stored in the queue 1132 whose priority level is M level, the scheduler unit 1140 reads a maximum of three medium priority frames at a time. Then, scheduler section 1140 transmits the read three medium priority frames to transmission section 1150 in a band of 5 Mbps or more and 900 Mbps or less. In this case, the transmission unit 1150 transmits the received frame to the server 50 in a band of 5 Mbps or more and 900 Mbps or less.

  In addition, the scheduler unit 1140 that operates based on the WRR method and is set based on the reference setting data table T100 performs the following processing.

  The scheduler unit 1140 reads up to four high-priority frames continuously from the H level queue (queue 1131) at a time, and then continuously from the M level queue (queue 1132) at a time. A maximum of three medium priority frames are read, and then a maximum of one low priority frame is read continuously from the L-level queue (queue 1133) at a time. Note that, after reading the frame from the L level queue, the scheduler unit 1140 repeats the process of reading the frame in the order of the H, M, and L level queues as described above.

  Data transmission unit 1300 includes a reception unit 1310, a classification unit 1320, and a storage unit 1330.

  The receiving unit 1310 receives a frame (data) from the server 50. The receiving unit 1310 transmits the frame received from the server 50 to the classification unit 1320.

  The storage unit 1330 includes queues 1331, 1332, and 1333. Here, the queue is a storage location for storing data (frames) provided in the storage unit 1330. Note that the number of queues in the storage unit 1330 may be four or more. The queues 1331, 1332, and 1333 in the storage unit 1330 have a higher priority in the order of the queues 1333, 1332, and 1331, for example. That is, frames with high priority are stored in the order of the queues 1333, 1332, and 1331.

  The plurality of queues are not limited to the higher priority in the order of the queues 1333, 1332, and 1331. For example, the priority may increase in the order of the queues 1331, 1332, and 1333.

Control unit 1400 further performs setting of classification unit 1320.
The classification unit 1320 classifies the received frames based on the settings of the control unit 1400. The setting of the classification unit 1320 is, for example, a setting in which queue the classification unit 1320 stores a frame based on the priority of the received frame.

  Specifically, the classification unit 1320 stores the received frame in accordance with the priority of the received frame, for example, the TOS field, based on the setting of the control unit 1400, similarly to the classification unit 1120. Store in the queue. For example, when the priority of the TOS field of the received frame is “1”, the classification unit 1320 stores the received frame (low priority frame) in the queue 1333 in the storage unit 1330. The classification unit 1320 stores the high priority frame, the medium priority frame, and the low priority frame in the queues 1331, 1332, and 1333, respectively.

  Accordingly, the priority levels of the queues 1331, 1332, and 1333 are the H, M, and L levels, respectively, like the queues 1131, 1132, and 1133 described above.

  Data transmission unit 1300 further includes a scheduler unit 1340 and a transmission unit 1350. The scheduler unit 1340 is a scheduler that operates based on the WRR method. The control unit 1400 further sets various parameters of the scheduler unit 1340 based on the reference setting data table T100 of FIG. 4A read from the storage unit 1500. The various parameters include a weight, a minimum guaranteed bandwidth, a maximum allowable bandwidth, and the like in the downstream direction, which will be described later.

  The transmission unit 1350 receives the frame transmitted from the scheduler unit 1340, converts the received frame into an optical signal, and transmits the optical signal to the ONU that is the destination of the frame via the logical path A.

  Here, the minimum guaranteed bandwidth, the maximum allowable bandwidth and the weight in the H-level frame (queue) in the downlink direction, which are various parameters of the scheduler unit 1340 set based on the reference setting data table T100, are 10 Mbps, 1000 Mbps, 4 pieces. Further, the minimum guaranteed bandwidth, the maximum allowable bandwidth and the weight in the M-level frame (queue) in the downlink direction, which are various parameters of the scheduler unit 1340 set based on the reference setting data table T100, are 5 Mbps and 900 Mbps, respectively. , Will be three. Also, the minimum guaranteed bandwidth, the maximum allowable bandwidth and the weight in the L-level frame (queue) in the downlink direction, which are various parameters of the scheduler unit 1340 set based on the reference setting data table T100, are 1 Mbps and 800 Mbps, respectively. , One.

  Based on the reference setting data table T100, the set scheduler unit 1340 performs, for example, the following processing.

  When three low priority frames in the downlink direction are stored in the queue 1333 in which low priority frames having a priority level of L level are stored, the scheduler unit 1340 continuously outputs one low priority at a maximum. Read the frame. Then, scheduler section 1340 transmits one read low priority frame to transmission section 1350 in a band of 1 Mbps or more and 800 Mbps or less. In this case, the transmission unit 1350 converts the received frame into an optical signal in a band of 1 Mbps or more and 800 Mbps or less, and transmits the optical signal to the ONU that is the destination of the frame via the logical path A.

  The scheduler unit 1340 that operates based on the WRR method and is set based on the reference setting data table T100 performs the following processing.

  The scheduler unit 1340 reads up to four high-priority frames continuously from the H level queue (queue 1331) at a time, and then continuously from the M level queue (queue 1332) at a time. A maximum of three medium priority frames are read out, and then a maximum of one low priority frame is read continuously at a time from the L level queue (queue 1333). In addition, after reading the frame from the L-level queue, the scheduler unit 1340 repeats the process of reading the frame as described above in the order of the H, M, and L-level queues.

  Next, communication amount control processing performed by the OLT 1000 will be described. The traffic control process is a process for dynamically changing the traffic according to the communication status.

  FIG. 5 is a diagram illustrating a flowchart of the traffic control process. Referring to FIG. 5, in step S110, a frame monitoring process is performed. In the frame monitoring process, the control unit 1400 performs a count process for a frame having a specific source address (SA). Here, the transmission source addresses (SA) of the PCs 210.1, 210.2, and 210.3 in FIG. 1 are α, β, and γ, respectively.

  In the present embodiment, it is assumed that the specific source address (SA) is β as an example. That is, it is assumed that the count process is performed on the destination address (DA) of the frame transmitted by the PC 210.2.

  Specifically, the control unit 1400 monitors frames received by the classification unit 1120 (hereinafter also referred to as reception frames). When the transmission source address (SA) of the received frame is β, a count process is performed.

  In the counting process, the control unit 1400 increments the counter K by 1. The counter K is a counter for counting the number of specific reception frames. Note that the initial value of the counter K is 0.

  In the count process, the control unit 1400 further associates the destination address (DA) of the received frame for which the counter K is incremented by 1 with the priority level of the received frame, and stores it as received frame data as the storage unit 1500. Remember me. Thereafter, the process proceeds to step S112.

  In step S112, control unit 1400 determines whether or not the value of counter K is a predetermined value. Here, it is assumed that the predetermined value is 1000, for example. If YES in step S112, the process proceeds to step S120. On the other hand, if NO at step S112, the process at step S110 is performed again.

  Therefore, the process of step S110 is repeated until it is determined as YES in step S110. In the present embodiment, the frame to be monitored is a received frame whose transmission source address (SA) is β. Therefore, the process of step S110 is repeated until 1000 received frames with a source address (SA) of β are counted. If it is determined as YES in step S110, the process proceeds to step S120.

  In step S120, a counting process is performed. In the aggregation process, the control unit 1400 aggregates the received frame data stored in the storage unit 1500 by the process of step S110 to generate aggregate data. Assume that the generated aggregate data is, for example, the following aggregate data D200. Thereafter, the process of step S120 ends.

  FIG. 6 is a diagram illustrating the total data D200 as an example. Referring to FIG. 6, aggregated data D200 is received frame data having the same combination of destination address (DA) and priority level out of 1000 received frame data, and is ranked from a large number of received frame data. It is data. The total data D200 indicates that, for example, 800 received frames having a destination address (DA) of α and a priority level of L level are counted.

  Referring to FIG. 5 again, when the process of step S120 ends, the process proceeds to step S122.

  In step S122, the control unit 1400 refers to the generated aggregated data, and receives 0 reception frames whose H level reception frames are 0 and whose number of L level reception frames is to be generated. It is determined whether it is 80% or more of the total number of frame data. In addition, said 80% is an example and may be another ratio (for example, 50%). If YES in step S122, the process proceeds to step S130 described later. On the other hand, if NO at step S122, the process proceeds to step S124.

  Here, it is assumed that the total number of received frame data for which the aggregated data is generated is 1000. Under this condition, the aggregate data is data indicating that there are one or more H level received frames, or the aggregate data is data indicating that the number of L level received frames is less than 800. In step S122, NO is determined, and the process proceeds to step S124.

  In step S124, control unit 1400 sets the value of counter K to zero. Thereafter, the process proceeds to step S126.

  In step S126, control unit 1400 deletes all received frame data stored in storage unit 1500. Thereafter, the process of step S110 is performed again.

  When the aggregate data referred to in the determination in step S122 is the aggregate data D200 in FIG. 6, it is determined YES in step S122, and the process proceeds to step S130. If YES is determined in step S122, it is a case where many frames transmitted from the PC 210.2 having the transmission source address (SA) β and having the destination address (DA) α are low priority frames. In this case, since the maximum allowable bandwidth of the low priority frame with the priority level of L level is limited to 800 Mbps by the reference setting data table T100 of FIG. 4A, the communication efficiency is lowered.

  In step S130, a setting change process is performed. In the setting change process, the control unit 1400 changes the setting of the scheduler unit 1140 based on the communication efficiency improvement setting data table. Note that the communication efficiency improvement setting data table is stored in the storage unit 1500 in advance. Therefore, the control unit 1400 sets the scheduler unit 1140 based on the communication efficiency improvement setting data table read from the storage unit 1500.

  The communication efficiency improvement setting data table is a data table in a case where the OLT 1000 assumes a communication state in which no high priority frame is received. The communication efficiency improvement setting data table is a data table when the OLT 1000 assumes a communication state in which each medium priority frame and low priority frame are received with a large bias. Note that the communication efficiency improvement setting data table may be a data table when the OLT 1000 assumes a communication state in which only a low priority frame is received.

  The communication efficiency improvement setting data table is, for example, the following communication efficiency improvement setting data table T100N.

  Referring to FIG. 4 again, FIG. 4B is a diagram showing an example of the communication efficiency improvement setting data table T100N. Referring to FIG. 4B, the communication efficiency improvement setting data table T100N is different in frame setting data of numbers “2” and “3” compared to the reference setting data table T100. Other than that, it is the same as the reference setting data table T100, and the detailed description will not be repeated.

  Compared with the frame setting data of number “2” in the reference setting data table T100, the frame setting data of number “2” in the communication efficiency improvement setting data table T100N has three weights in the up and down directions. The difference is that there are two.

  Compared with the frame setting data of number “3” in the reference setting data table T100, the frame setting data of number “3” in the communication efficiency improvement setting data table T100N has a minimum guaranteed bandwidth of 1 Mbps in the uplink and downlink directions. Instead, the point is 3 Mbps, the maximum allowable bandwidth in the upstream and downstream directions is 900 Mbps instead of 800 Mbps, and the point that the upstream and downstream weights are two instead of one. Different.

  Of the various parameters of the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100N, the parameters changed from the various parameters of the scheduler unit 1140 set based on the reference setting data table T100 are M in the uplink direction. A weight corresponding to a level frame (queue) and a minimum guaranteed bandwidth, a maximum allowable bandwidth and a weight corresponding to an L-level frame (queue) in the upstream direction.

  The weight corresponding to the M level frame (queue) in the upstream direction is changed from three to two. The minimum guaranteed bandwidth corresponding to the L-level frame (queue) in the upstream direction is changed from 1 Mbps to 3 Mbps. The maximum allowable bandwidth corresponding to the L-level frame (queue) in the upstream direction is changed from 800 Mbps to 900 Mbps. The weight corresponding to the L-level frame (queue) in the upstream direction is changed from one to two.

  The scheduler unit 1140 that operates based on the WRR scheme and is set based on the communication efficiency improvement setting data table T100N performs the following processing. In this case, it is assumed that a high priority frame is not stored in the H level queue (queue 1131).

  The scheduler unit 1140 reads a maximum of two middle priority frames from the M level queue (queue 1132) at a time, and then continuously from the L level queue (queue 1133) at a time. Read up to two low priority frames. Here, it is assumed that many of the low-priority frames that the scheduler unit 1140 reads from the L-level queue are frames whose destination address (DA) is α, for example, as indicated by the aggregated data D200 in FIG. Note that, after reading the frame from the L-level queue, the scheduler unit 1140 repeats the process of reading the frame again in the order of the M and L-level queues.

  Therefore, the number (2) of medium priority frames read continuously by the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100N at a time is the scheduler unit 1140 set based on the reference setting data table T100. Is smaller than the number of medium priority frames (3) read continuously at a time.

  In addition, the number (2) of low-priority frames that the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100N continuously reads at a time is the scheduler unit 1140 set based on the reference setting data table T100. Is larger than the number (1) of low priority frames read continuously at a time.

  Thus, the low priority frame can be processed efficiently in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Further, based on the communication efficiency improvement setting data table T100N, the set scheduler unit 1140 performs the following processing.

  The scheduler unit 1140 sequentially transmits the low-priority frames read sequentially by the above processing to the transmission unit 1150 in a band of 3 Mbps or more and 900 Mbps or less. The transmission unit 1150 transmits the received low priority frame to the server 50 in a band of 3 Mbps or more and 900 Mbps or less.

  Therefore, the maximum allowable bandwidth (900 Mbps) for the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100N to transmit the low priority frame is determined by the scheduler unit 1140 set based on the reference setting data table T100. It is larger than the maximum allowable bandwidth (800 Mbps) for transmitting a low priority frame.

  Thus, the low priority frame can be processed efficiently in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Note that many of the frames transmitted to the server 50 are low-priority frames whose destination address (DA) is α. Therefore, when receiving the low priority frame whose destination address (DA) is α, the server 50 transmits the received low priority frame to the OLT 1000 capable of data communication with the PC 210.1 whose destination address (DA) is α. Therefore, by the above-described operations of the receiving unit 1310 and the classification unit 1320, many low-priority frames having a destination address (DA) of α are sequentially stored in the L-level queue (queue 1333) in the storage unit 1330.

  In the setting change process in step S130, the control unit 1400 further changes the setting of the scheduler unit 1340 based on the communication efficiency improvement setting data table. Assume that the communication efficiency improvement setting data table is, for example, the communication efficiency improvement setting data table T100N of FIG. And the process of step S130 is complete | finished.

  Of the various parameters of the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100N, the parameters changed from the various parameters of the scheduler unit 1340 set based on the reference setting data table T100 are M in the downlink direction. A weight corresponding to a level frame (queue) and a minimum guaranteed bandwidth, a maximum allowable bandwidth, and a weight corresponding to an L-level frame (queue) in the downlink direction.

  The weight corresponding to the M level frame (queue) in the downstream direction is changed from three to two. The minimum guaranteed band corresponding to the L-level frame (queue) in the downlink direction is changed from 1 Mbps to 3 Mbps. The maximum allowable bandwidth corresponding to the downlink L level frame (queue) is changed from 800 Mbps to 900 Mbps. The weight corresponding to the L level frame (queue) in the downlink direction is changed from one to two.

  The scheduler unit 1340 that operates based on the WRR method and is set based on the communication efficiency improvement setting data table T100N performs the following processing. In this case, it is assumed that a high priority frame is not stored in the H level queue (queue 1331).

  The scheduler unit 1340 reads a maximum of two middle priority frames from the M level queue (queue 1332) at a time, and then continuously from the L level queue (queue 1333) at a time. Read up to two low priority frames. Here, most of the low-priority frames read by the scheduler unit 1340 from the L-level queue (queue 1333) are frames whose destination address (DA) is α. Note that, after reading the frame from the L-level queue, the scheduler unit 1340 repeats the process of reading the frame again in the order of the M and L-level queues.

  Therefore, the number (2) of medium priority frames read continuously by the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100N at a time is the scheduler unit 1340 set based on the reference setting data table T100. Is smaller than the number of medium priority frames (3) read continuously at a time.

  In addition, the number (2) of low-priority frames that the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100N continuously reads at a time is the scheduler unit 1340 set based on the reference setting data table T100. Is larger than the number (1) of low priority frames read continuously at a time.

  Thus, the low priority frame can be processed efficiently in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Further, based on the communication efficiency improvement setting data table T100N, the set scheduler unit 1340 performs the following processing.

  The scheduler unit 1340 sequentially transmits sequentially read frames to the transmission unit 1350 in a band of 3 Mbps or more and 900 Mbps or less by the above processing. The transmission unit 1350 transmits the received frame to the frame destination via the logical path A in a band of 3 Mbps or more and 900 Mbps or less.

  Therefore, the maximum allowable bandwidth (900 Mbps) for the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100N to transmit the low priority frame is set by the scheduler unit 1340 set based on the reference setting data table T100. It is larger than the maximum allowable bandwidth (800 Mbps) for transmitting a low priority frame.

  Thus, the low priority frame can be processed efficiently in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Note that many of the frames transmitted by the transmission unit 1350 are low priority frames having a destination address (DA) of α. Therefore, when receiving the low priority frame whose destination address (DA) is α, the transmission unit 1350 performs data communication with the PC 210.1 whose destination address (DA) is α via the logical path A. Send to possible ONU 200.1. Then, the ONU 200.1 that has received the low-priority frame whose destination address (DA) is α transmits the received frame to the PC 210.1.

  Referring to FIG. 5 again, when the process of step S130 ends, the process proceeds to step S150.

  In step S150, a frame monitoring process N is performed. In the frame monitoring process A, as in step S110, the control unit 1400 performs the monitoring process N on a frame with a specific source address (SA).

  In the present embodiment, it is assumed that the specific source address (SA) is β as an example. That is, it is assumed that the monitoring process N is performed on the destination address (DA) of the frame transmitted by the PC 210.2.

  Specifically, the control unit 1400 monitors a received frame received by the classification unit 1120. When the transmission source address (SA) of the received frame is β, the monitoring process N is performed.

  In the monitoring process N, the control unit 1400 associates the destination address (DA) of the received frame with the priority level of the received frame, and stores it in the storage unit 1500 as received frame data. Then, control unit 1400 deletes the oldest one received frame data stored in storage unit 1500. Thus, 1000 pieces of received frame data are always stored in the storage unit 1500. Thereafter, the process proceeds to step S160.

  In step S160, an aggregation process N is performed. Since the counting process N is the same as the counting process in step S120, detailed description will not be repeated. Thereafter, the process proceeds to step S162.

  In step S162, the control unit 1400 generates aggregated data with reference to the aggregated data generated by the aggregate process N and the condition that there are one or more H level received frames and the number of L level received frames. It is determined whether or not one of the conditions is 30% or less of the total number of received frame data to be processed. In addition, said 30% is an example and may be another ratio (for example, 40%). If YES in step S162, the process proceeds to step S170. On the other hand, if NO at step S162, the process at step S150 is performed again.

  In step S170, a setting change release process is performed. In the setting change canceling process, a process for restoring the setting changed in step S130 is performed. Specifically, control unit 1400 sets scheduler unit 1140 and scheduler unit 1340 based on the reference setting data table read from storage unit 1500. Assume that the reference setting data table is, for example, the reference setting data table T100 in FIG. Thereby, each setting of scheduler unit 1140 and scheduler unit 1340 is returned to the state before the setting change process of step S130. Thereafter, the process of step S124 is performed again.

  As described above, in the present embodiment, when a situation where many low priority frames have to be processed, each of the scheduler unit 1140 and the scheduler unit 1340 continuously reads low priority frames. Set to increase the number. Thereby, a low priority frame can be processed efficiently. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Also, in this embodiment, when it becomes a situation where many low priority frames must be processed, each of scheduler unit 1140 and scheduler unit 1340 is configured to increase the maximum allowable bandwidth for transmitting low priority frames. To do. Thereby, a low priority frame can be processed efficiently. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

<Variation 1 of the first embodiment>
In the present embodiment, a setting change process of the scheduler unit for reducing the maximum allowable bandwidth for transmitting the medium priority frame in a situation where many low priority frames must be processed will be described.

  Since the network system in the present embodiment is similar to communication system 10000 in the first embodiment, detailed description will not be repeated. Since the configuration of OLT 1000 is the same as the configuration described in the first embodiment, detailed description will not be repeated.

  Next, the traffic control process A performed by the OLT 1000 in the present embodiment will be described. The traffic control process A is a process for dynamically changing the traffic according to the communication status. It is assumed that the communication state of the OLT 1000 when the communication amount control process A of the present embodiment is performed is the same as the communication state of the OLT 1000 when the communication amount control process of the first embodiment is performed. For example, in the traffic control process A of the present embodiment, it is assumed that the aggregate data generated in step S120 is the aggregate data D200 in FIG.

  Note that the various parameters of the scheduler unit 1140 and the scheduler unit 1340 are set in advance based on the reference setting data table T100 in FIG. 4A, as described in the first embodiment. To do.

  FIG. 7 is a flowchart of the traffic control process A. Referring to FIG. 7, the traffic control process A is different from the traffic control process of FIG. 5 in that step S130A is performed instead of step S130. Other than that, it is the same as the traffic control process, and the detailed description will not be repeated.

  In the present embodiment, a portion that performs processing different from that of the first embodiment will be mainly described. If YES is determined in the step S122, the process proceeds to a step S130A.

  In step S130A, setting change processing A is performed as in step S130 of FIG. In the setting change process A, the control unit 1400 changes the setting of the scheduler unit 1140 based on the following communication efficiency improvement setting data table T100A. The communication efficiency improvement setting data table A is stored in the storage unit 1500 in advance. Therefore, control unit 1400 sets scheduler unit 1140 based on communication efficiency improvement setting data table A read from storage unit 1500.

  The communication efficiency improvement setting data table A is a data table in a case where the OLT 1000 assumes a communication state in which no high priority frame is received. The communication efficiency improvement setting data table A is a data table when the OLT 1000 assumes a communication state in which each medium priority frame and low priority frame are received with a large bias. The communication efficiency improvement setting data table A may be a data table when the OLT 1000 assumes a communication state in which only a low priority frame is received.

  FIG. 8 is a diagram illustrating a communication efficiency improvement setting data table T100A as an example. Referring to FIG. 8, communication efficiency improvement setting data table T100A differs in frame setting data of numbers “2” and “3” compared to reference setting data table T100 of FIG. Other than that, it is the same as the reference setting data table T100, and the detailed description will not be repeated.

  Compared with the frame setting data of number “2” in the reference setting data table T100, the frame setting data of number “2” in the communication efficiency improvement setting data table T100A has a minimum guaranteed bandwidth of 5 Mbps in the upstream and downstream directions. Instead, the point is 4 Mbps, the maximum allowable bandwidth in the uplink and downlink directions is 800 Mbps instead of 900 Mbps, and the point that the uplink and downlink weights are two instead of three. Different.

  Compared with the frame setting data of number “3” in the reference setting data table T100, the frame setting data of number “3” in the communication efficiency improvement setting data table T100A has one weight in the up and down directions. The difference is that there are two.

  Of the various parameters of the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100A, the parameters changed from the various parameters of the scheduler unit 1140 set based on the reference setting data table T100 are M in the uplink direction. The minimum guaranteed bandwidth, the maximum allowable bandwidth and the weight corresponding to the level frame (queue), and the weight corresponding to the L-level frame (queue) in the upstream direction.

  The minimum guaranteed bandwidth corresponding to the M-level frame (queue) in the upstream direction is changed from 5 Mbps to 4 Mbps. The maximum allowable bandwidth corresponding to an M-level frame (queue) in the upstream direction is changed from 900 Mbps to 800 Mbps. The weight corresponding to the M level frame (queue) in the upstream direction is changed from three to two. The weight corresponding to the L-level frame (queue) in the upstream direction is changed from one to two.

  The scheduler unit 1140 that operates based on the WRR method and is set based on the communication efficiency improvement setting data table T100A performs the following processing. In this case, it is assumed that the high priority frame is not stored in the H level queue (queue 1131), as in the first embodiment.

  The scheduler unit 1140 reads a maximum of two middle priority frames from the M level queue (queue 1132) at a time, and then continuously from the L level queue (queue 1133) at a time. Read up to two low priority frames. Here, it is assumed that many of the low-priority frames that the scheduler unit 1140 reads from the L-level queue are frames whose destination address (DA) is α, for example, as indicated by the aggregated data D200 in FIG. Note that, after reading the frame from the L-level queue, the scheduler unit 1140 repeats the process of reading the frame again in the order of the M and L-level queues.

  Therefore, the number (2) of medium priority frames that the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100A continuously reads at a time is the scheduler unit 1140 set based on the reference setting data table T100. Is smaller than the number of medium priority frames (3) read continuously at a time.

  Further, the number (2) of low priority frames that the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100A continuously reads at a time is the scheduler unit 1140 set based on the reference setting data table T100. Is larger than the number (1) of low priority frames read continuously at a time.

  Thus, the low priority frame can be processed efficiently in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Further, based on the communication efficiency improvement setting data table T100A, the set scheduler unit 1140 performs the following processing.

  The scheduler unit 1140 sequentially transmits the medium priority frames read sequentially by the above processing to the transmission unit 1150 in a band of 4 Mbps or more and 800 Mbps or less. The transmission unit 1150 transmits the received medium priority frame to the server 50 in a band of 4 Mbps or more and 800 Mbps or less.

  In addition, the scheduler unit 1140 sequentially transmits the low-priority frames read sequentially by the above processing to the transmission unit 1150 in a band of 1 Mbps or more and 800 Mbps or less. The transmission unit 1150 transmits the received low priority frame to the server 50 in a band of 1 Mbps or more and 800 Mbps or less.

  Accordingly, the maximum allowable bandwidth (800 Mbps) for the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100A to transmit the medium priority frame is determined by the scheduler unit 1140 set based on the reference setting data table T100. It is smaller than the maximum allowable bandwidth (900 Mbps) for transmitting the medium priority frame. As a result, when the medium priority frame temporarily increases in a burst manner, the maximum allowable bandwidth is changed to a small value, so that instead of reducing the bandwidth for transmitting the medium priority frame, the low priority frame is changed. Sufficient bandwidth for transmission can be secured.

  As a result, the low priority frame can be efficiently processed when the medium priority frame temporarily increases in a burst manner and in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Note that many of the frames transmitted to the server 50 are low-priority frames whose destination address (DA) is α. Therefore, when receiving the low priority frame whose destination address (DA) is α, the server 50 transmits the received low priority frame to the OLT 1000 capable of data communication with the PC 210.1 whose destination address (DA) is α. Therefore, by the above-described operations of the receiving unit 1310 and the classification unit 1320, many low-priority frames having a destination address (DA) of α are sequentially stored in the L-level queue (queue 1333) in the storage unit 1330.

  In the setting change process A in step S130A, the control unit 1400 further changes the setting of the scheduler unit 1340 based on the communication efficiency improvement setting data table T100A read from the storage unit 1500. Then, the process of step S130A ends.

  Of the various parameters of the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100A, the parameters changed from the various parameters of the scheduler unit 1340 set based on the reference setting data table T100 are M in the downlink direction. The minimum guaranteed bandwidth, the maximum allowable bandwidth and the weight corresponding to the level frame (queue), and the weight corresponding to the L-level frame (queue) in the downlink direction.

  The minimum guaranteed bandwidth corresponding to the M level frame (queue) in the downstream direction is changed from 5 Mbps to 4 Mbps. The maximum allowable bandwidth corresponding to the M level frame (queue) in the downlink direction is changed from 900 Mbps to 800 Mbps. The weight corresponding to the M level frame (queue) in the downstream direction is changed from three to two. The weight corresponding to the L level frame (queue) in the downlink direction is changed from one to two.

  The scheduler unit 1340 that operates based on the WRR method and is set based on the communication efficiency improvement setting data table T100A performs the following processing. In this case, as in the first embodiment, it is assumed that no high priority frame is stored in the H level queue (queue 1331).

  The scheduler unit 1340 reads a maximum of two middle priority frames from the M level queue (queue 1332) at a time, and then continuously from the L level queue (queue 1333) at a time. Read up to two low priority frames. Here, it is assumed that many of the low priority frames read by the scheduler unit 1340 from the L-level queue are frames whose destination address (DA) is α, for example, as indicated by the aggregated data D200 in FIG. Note that, after reading the frame from the L-level queue, the scheduler unit 1340 repeats the process of reading the frame again in the order of the M and L-level queues.

  Therefore, the number (2) of medium priority frames read continuously by the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100A at a time is the scheduler unit 1140 set based on the reference setting data table T100. Is smaller than the number of medium priority frames (3) read continuously at a time.

  In addition, the number (2) of low-priority frames that the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100A continuously reads at a time is the scheduler unit 1140 set based on the reference setting data table T100. Is larger than the number (1) of low priority frames read continuously at a time.

  Thus, the low priority frame can be processed efficiently in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Further, based on the communication efficiency improvement setting data table T100A, the set scheduler unit 1340 performs the following processing.

  The scheduler unit 1340 sequentially transmits the medium priority frames read sequentially by the above processing to the transmission unit 1350 in a band of 4 Mbps or more and 800 Mbps or less. The transmission unit 1350 transmits the received medium priority frame to the frame destination via the logical path A in a band of 4 Mbps or more and 800 Mbps or less.

  In addition, the scheduler unit 1340 sequentially transmits the low-priority frames read sequentially by the above process to the transmission unit 1350 in a band of 1 Mbps or more and 800 Mbps or less. The transmission unit 1350 transmits the received low priority frame to the frame destination via the logical path A in a band of 1 Mbps or more and 800 Mbps or less.

  Accordingly, the maximum allowable bandwidth (800 Mbps) for the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100A to transmit the medium priority frame is determined by the scheduler unit 1340 set based on the reference setting data table T100. It is smaller than the maximum allowable bandwidth (900 Mbps) for transmitting the medium priority frame. As a result, when the medium priority frame temporarily increases in a burst manner, the maximum allowable bandwidth is changed to a small value, so that instead of reducing the bandwidth for transmitting the medium priority frame, the low priority frame is changed. Sufficient bandwidth for transmission can be secured.

  As a result, the low priority frame can be efficiently processed when the medium priority frame temporarily increases in a burst manner and in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Referring to FIG. 7 again, when the process of step S130A is completed, the processes of steps S150, S160, and S162 are sequentially performed as in the first embodiment. If it is determined as YES in step S162, the process proceeds to step S170.

  In step S170, a setting change release process is performed as in the first embodiment. In the setting change canceling process, a process for restoring the setting changed in step S130A is performed. Specifically, the control unit 1400 sets the scheduler unit 1140 and the scheduler unit 1340 based on the reference setting data table T100 of FIG. 4A read from the storage unit 1500. Thereby, each setting of scheduler unit 1140 and scheduler unit 1340 is returned to the state before the setting change process of step S130A. Thereafter, the process of step S124 is performed again.

  As described above, in the present embodiment, when a situation in which many low priority frames have to be processed, the maximum allowable bandwidth in which each of the scheduler unit 1140 and the scheduler unit 1340 transmits a medium priority frame is reduced. Set to As a result, when the medium priority frame temporarily increases in a burst manner, the maximum allowable bandwidth is changed to a small value, so that instead of reducing the bandwidth for transmitting the medium priority frame, the low priority frame is changed. Sufficient bandwidth for transmission can be secured.

  As a result, the low priority frame can be efficiently processed when the medium priority frame temporarily increases in a burst manner and in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

<Modification 2 of the first embodiment>
In the present embodiment, setting change processing of the scheduler unit that is different from the first embodiment and the first modification of the first embodiment will be described.

  Since the network system in the present embodiment is similar to communication system 10000 in the first embodiment, detailed description will not be repeated. Since the configuration of OLT 1000 is the same as the configuration described in the first embodiment, detailed description will not be repeated.

  Next, the traffic control process B performed by the OLT 1000 in the present embodiment will be described. The traffic control process B is a process for dynamically changing the traffic according to the communication status. Note that the communication state of the OLT 1000 when the communication amount control process B of the present embodiment is performed is the same as the communication state of the OLT 1000 when the communication amount control process of the first embodiment is performed. For example, in the traffic control process B of the present embodiment, it is assumed that the aggregate data generated in step S120 is the aggregate data D200 in FIG.

  Note that the various parameters of the scheduler unit 1140 and the scheduler unit 1340 are set in advance based on the reference setting data table T100 in FIG. 4A, as described in the first embodiment. To do.

  FIG. 9 is a diagram illustrating a flowchart of the traffic control process B. Referring to FIG. 9, the traffic control process B is different from the traffic control process of FIG. 5 in that step S130B is performed instead of step S130. Other than that, it is the same as the traffic control process, and the detailed description will not be repeated.

  In the present embodiment, a portion that performs processing different from that of the first embodiment will be mainly described. If YES is determined in the step S122, the process proceeds to a step S130B.

  In step S130B, setting change processing B is performed as in step S130 of FIG. In the setting change process B, the control unit 1400 changes the setting of the scheduler unit 1140 based on the following communication efficiency improvement setting data table T100B. Note that the communication efficiency improvement setting data table B is stored in the storage unit 1500 in advance. Therefore, control unit 1400 sets scheduler unit 1140 based on communication efficiency improvement setting data table B read from storage unit 1500.

  The communication efficiency improvement setting data table B is a data table when the OLT 1000 assumes a communication state in which no high priority frame is received. The communication efficiency improvement setting data table B is a data table when the OLT 1000 assumes a communication state in which each medium priority frame and low priority frame are received with a large bias. The communication efficiency improvement setting data table B may be a data table when the OLT 1000 assumes a communication state in which only the low priority frame is received.

  FIG. 10 is a diagram illustrating a communication efficiency improvement setting data table T100B as an example. Referring to FIG. 10, communication efficiency improvement setting data table T100B is different in frame setting data of numbers “2” and “3” compared to reference setting data table T100 of FIG. Other than that, it is the same as the reference setting data table T100, and the detailed description will not be repeated.

  The frame setting data with the number “2” in the communication efficiency improvement setting data table T100B has three weights in the up and down directions compared to the frame setting data with the number “2” in the reference setting data table T100. The difference is that there are two.

  Compared with the frame setting data of number “3” in the reference setting data table T100, the frame setting data of number “3” in the communication efficiency improvement setting data table T100B has a minimum guaranteed bandwidth of 1 Mbps in the upstream and downstream directions. Instead, the point is 5 Mbps, the maximum allowable bandwidth in the upstream and downstream directions is 900 Mbps instead of 800 Mbps, and the point that the weights in the upstream and downstream directions are two instead of one. Different.

  That is, the maximum allowable bandwidth in the uplink direction and the downlink direction indicated by the frame setting data with the number “3” in the communication efficiency improvement setting data table T100B is the uplink indicated by the frame setting data with the number “2” in the communication efficiency improvement setting data table T100B. This is the same as the maximum allowable bandwidth in the direction and the downlink direction. That is, in the communication efficiency improvement setting data table T100B, compared to the reference setting data table T100, the maximum allowable bandwidth of the frame having the priority level of L level is replaced with the maximum allowable bandwidth of the frame having the priority level of M level. Become.

  Of the various parameters of the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100B, the parameters changed from the various parameters of the scheduler unit 1140 set based on the reference setting data table T100 are M in the uplink direction. A weight corresponding to a level frame (queue) and a minimum guaranteed bandwidth, a maximum allowable bandwidth and a weight corresponding to an L-level frame (queue) in the upstream direction.

  The weight corresponding to the M level frame (queue) in the upstream direction is changed from three to two. The minimum guaranteed bandwidth corresponding to the L-level frame (queue) in the upstream direction is changed from 1 Mbps to 5 Mbps. The maximum allowable bandwidth corresponding to the L-level frame (queue) in the upstream direction is changed from 800 Mbps to 900 Mbps. The weight corresponding to the L-level frame (queue) in the upstream direction is changed from one to two.

  That is, in the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100B, the values of various parameters in the uplink L level are the same as the values of various parameters in the uplink M level.

  The scheduler unit 1140 that operates based on the WRR method and is set based on the communication efficiency improvement setting data table T100B performs the following processing. In this case, it is assumed that the high priority frame is not stored in the H level queue (queue 1131), as in the first embodiment.

  The scheduler unit 1140 reads a maximum of two middle priority frames from the M level queue (queue 1132) at a time, and then continuously from the L level queue (queue 1133) at a time. Read up to two low priority frames. Here, it is assumed that many of the low-priority frames that the scheduler unit 1140 reads from the L-level queue are frames whose destination address (DA) is α, for example, as indicated by the aggregated data D200 in FIG. Note that, after reading the frame from the L-level queue, the scheduler unit 1140 repeats the process of reading the frame again in the order of the M and L-level queues.

  Therefore, the number (2) of medium priority frames that the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100B reads continuously at a time is the scheduler unit 1140 set based on the reference setting data table T100. Is smaller than the number of medium priority frames (3) read continuously at a time.

  In addition, the number (2) of low-priority frames that the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100B continuously reads at a time is the scheduler unit 1140 set based on the reference setting data table T100. Is larger than the number (1) of low priority frames read continuously at a time.

  Thus, the low priority frame can be processed efficiently in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Further, based on the communication efficiency improvement setting data table T100B, the set scheduler unit 1140 performs the following processing.

  The scheduler unit 1140 sequentially transmits the low-priority frames read sequentially by the above processing to the transmission unit 1150 in a band of 5 Mbps or more and 900 Mbps or less. The transmission unit 1150 transmits the received low priority frame to the server 50 in a band of 5 Mbps or more and 900 Mbps or less.

  Accordingly, the maximum allowable bandwidth (900 Mbps) for the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100B to transmit the low priority frame is determined by the scheduler unit 1140 set based on the reference setting data table T100. It is larger than the maximum allowable bandwidth (800 Mbps) for transmitting a low priority frame.

  Thus, the low priority frame can be processed efficiently in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Note that many of the frames transmitted to the server 50 are low-priority frames whose destination address (DA) is α. Therefore, when receiving the low priority frame whose destination address (DA) is α, the server 50 transmits the received low priority frame to the OLT 1000 capable of data communication with the PC 210.1 whose destination address (DA) is α. Therefore, by the above-described operations of the receiving unit 1310 and the classification unit 1320, many low-priority frames having a destination address (DA) of α are sequentially stored in the L-level queue (queue 1333) in the storage unit 1330.

  In the setting change process B in step S130B, the control unit 1400 further changes the setting of the scheduler unit 1340 based on the communication efficiency improvement setting data table T100B read from the storage unit 1500. Then, the process of step S130B ends.

  Of the various parameters of the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100B, the parameters changed from the various parameters of the scheduler unit 1340 set based on the reference setting data table T100 are M in the downlink direction. A weight corresponding to a level frame (queue) and a minimum guaranteed bandwidth, a maximum allowable bandwidth, and a weight corresponding to an L-level frame (queue) in the downlink direction.

  The weight corresponding to the M level frame (queue) in the downstream direction is changed from three to two. The minimum guaranteed bandwidth corresponding to the downlink L level frame (queue) is changed from 1 Mbps to 5 Mbps. The maximum allowable bandwidth corresponding to the downlink L level frame (queue) is changed from 800 Mbps to 900 Mbps.

  That is, in the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100B, the values of the various parameters in the uplink L level are the same as the values of the parameters in the uplink M level.

  The scheduler unit 1340 that operates based on the WRR method and is set based on the communication efficiency improvement setting data table T100B performs the following processing. In this case, as in the first embodiment, it is assumed that no high priority frame is stored in the H level queue (queue 1331).

  The scheduler unit 1340 reads a maximum of two middle priority frames from the M level queue (queue 1332) at a time, and then continuously from the L level queue (queue 1333) at a time. Read up to two low priority frames. Here, it is assumed that many of the low priority frames read by the scheduler unit 1340 from the L-level queue are frames whose destination address (DA) is α, for example, as indicated by the aggregated data D200 in FIG. Note that, after reading the frame from the L-level queue, the scheduler unit 1340 repeats the process of reading the frame again in the order of the M and L-level queues.

  Therefore, the number (2) of medium priority frames read continuously by the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100B at a time is the scheduler unit 1140 set based on the reference setting data table T100. Is smaller than the number of medium priority frames (3) read continuously at a time.

  In addition, the number (2) of low-priority frames that the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100B reads continuously at one time is the scheduler unit 1140 set based on the reference setting data table T100. Is larger than the number (1) of low priority frames read continuously at a time.

  Thus, the low priority frame can be processed efficiently in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Further, based on the communication efficiency improvement setting data table T100B, the set scheduler unit 1340 performs the following processing.

  The scheduler unit 1340 sequentially transmits the low-priority frames read sequentially by the above processing to the transmission unit 1350 in a band of 5 Mbps or more and 900 Mbps or less. The transmission unit 1350 transmits the received low priority frame to the frame destination via the logical path A in a band of 5 Mbps or more and 900 Mbps or less.

  Therefore, the maximum allowable bandwidth (900 Mbps) for the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100N to transmit the low priority frame is set by the scheduler unit 1340 set based on the reference setting data table T100. It is larger than the maximum allowable bandwidth (800 Mbps) for transmitting a low priority frame.

  Thus, the low priority frame can be processed efficiently in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Referring to FIG. 9 again, when the process of step S130B ends, the processes of steps S150, S160, and S162 are sequentially performed as in the first embodiment. If it is determined as YES in step S162, the process proceeds to step S170.

  In step S170, a setting change release process is performed as in the first embodiment. In the setting change canceling process, a process for restoring the setting changed in step S130B is performed. Specifically, the control unit 1400 sets the scheduler unit 1140 and the scheduler unit 1340 based on the reference setting data table T100 of FIG. 4A read from the storage unit 1500. Thereby, each setting of scheduler unit 1140 and scheduler unit 1340 is returned to the state before the setting change process in step S130B. Thereafter, the process of step S124 is performed again.

  As described above, in the present embodiment, the communication efficiency improvement setting data table T100B in which the values of the various parameters at the L level in the uplink and the downlink and the values of the various parameters at the M level in the uplink and the downlink are the same. Is used. The communication efficiency improvement setting data table T100B has a smaller weight corresponding to the uplink M level frame (queue) than the reference setting data table T100, and the minimum corresponding to the uplink L level frame (queue). The guaranteed bandwidth, maximum allowable bandwidth and weight are large.

  Therefore, in the present embodiment, when it becomes a situation where many low priority frames must be processed, the various parameters of the scheduler unit 1140 and the scheduler unit 1340 are set based on the communication efficiency improvement setting data table T100B. Each of the scheduler unit 1140 and the scheduler unit 1340 is changed so as to increase the number of low-priority frames read continuously at a time. Thereby, a low priority frame can be processed efficiently. Even when it is necessary to process many frames with a low priority level of data transfer, it is possible to maintain high communication efficiency.

  Further, in the present embodiment, when a situation in which many low priority frames must be processed, various parameters of the scheduler unit 1140 and the scheduler unit 1340 are set based on the communication efficiency improvement setting data table T100B. Each of the scheduler unit 1140 and the scheduler unit 1340 is changed so as to increase the maximum allowable band for transmitting the low priority frame. Thereby, a low priority frame can be processed efficiently. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

<Modification 3 of the first embodiment>
In the present embodiment, in a situation where a large number of low priority frames must be processed, the maximum allowable bandwidth for transmitting the medium priority frame is set to be reduced, and the maximum allowable band for transmitting the low priority frame is set. A setting change process of the scheduler unit for increasing the bandwidth will be described.

  Since the network system in the present embodiment is similar to communication system 10000 in the first embodiment, detailed description will not be repeated. Since the configuration of OLT 1000 is the same as the configuration described in the first embodiment, detailed description will not be repeated.

  Next, the traffic control process C performed by the OLT 1000 in the present embodiment will be described. The traffic control process C is a process for dynamically changing the traffic according to the communication status. Note that the communication state of the OLT 1000 when the communication amount control process C of the present embodiment is performed is the same as the communication state of the OLT 1000 when the communication amount control process of the first embodiment is performed. For example, in the traffic control process C of the present embodiment, it is assumed that the aggregate data generated in step S120 is the aggregate data D200 in FIG.

  Note that the various parameters of the scheduler unit 1140 and the scheduler unit 1340 are set in advance based on the reference setting data table T100 in FIG. 4A, as described in the first embodiment. To do.

  FIG. 11 is a flowchart of the traffic control process C. Referring to FIG. 11, the traffic control process C is different from the traffic control process of FIG. 5 in that step S130C is performed instead of step S130. Other than that, it is the same as the traffic control process, and the detailed description will not be repeated.

  In the present embodiment, a portion that performs processing different from that of the first embodiment will be mainly described. If YES is determined in the step S122, the process proceeds to a step S130C.

  In step S130C, setting change processing C is performed as in step S130 of FIG. In the setting change process C, the control unit 1400 changes the setting of the scheduler unit 1140 based on the following communication efficiency improvement setting data table T100C. The communication efficiency improvement setting data table C is stored in the storage unit 1500 in advance. Therefore, the control unit 1400 sets the scheduler unit 1140 based on the communication efficiency improvement setting data table C read from the storage unit 1500.

  The communication efficiency improvement setting data table C is a data table in a case where a communication state in which the OLT 1000 has not received any high priority frame is assumed. The communication efficiency improvement setting data table C is a data table when the OLT 1000 assumes a communication state where the medium priority frame and the low priority frame are received with a large bias. Note that the communication efficiency improvement setting data table C may be a data table when the OLT 1000 assumes a communication state in which only a low priority frame is received.

  FIG. 12 is a diagram illustrating a communication efficiency improvement setting data table T100C as an example. Referring to FIG. 12, communication efficiency improvement setting data table T100C is different in frame setting data of numbers “2” and “3” compared to reference setting data table T100 of FIG. Other than that, it is the same as the reference setting data table T100, and the detailed description will not be repeated.

  Compared with the frame setting data of number “2” in the reference setting data table T100, the frame setting data of number “2” in the communication efficiency improvement setting data table T100C has a minimum guaranteed bandwidth of 5 Mbps in the uplink and downlink directions. Instead, the point is 4 Mbps, the maximum allowable bandwidth in the uplink and downlink directions is 800 Mbps instead of 900 Mbps, and the point that the uplink and downlink weights are two instead of three. Different.

  Compared with the frame setting data of number “3” in the reference setting data table T100, the frame setting data of number “3” in the communication efficiency improvement setting data table T100C has a minimum guaranteed bandwidth of 1 Mbps in the upstream and downstream directions. Instead, the point is 3 Mbps, the maximum allowable bandwidth in the upstream and downstream directions is 900 Mbps instead of 800 Mbps, and the point that the upstream and downstream weights are two instead of one. Different.

  Of the various parameters of the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100C, the parameters changed from the various parameters of the scheduler unit 1140 set based on the reference setting data table T100 are M in the uplink direction. The minimum guaranteed bandwidth, the maximum allowable bandwidth and the weight corresponding to the level frame (queue), and the minimum guaranteed bandwidth, the maximum allowable bandwidth and the weight corresponding to the L level frame (queue) in the uplink direction.

  The corresponding minimum guaranteed bandwidth corresponding to the M level frame (queue) in the upstream direction is changed from 5 Mbps to 4 Mbps. The corresponding maximum allowable bandwidth corresponding to the uplink M level frame (queue) is changed from 900 Mbps to 800 Mbps. The weight corresponding to the M level frame (queue) in the upstream direction is changed from three to two.

  The corresponding minimum guaranteed bandwidth corresponding to the uplink L level frame (queue) is changed from 1 Mbps to 3 Mbps. The corresponding maximum allowable bandwidth corresponding to the uplink L level frame (queue) is changed from 800 Mbps to 900 Mbps. The weight corresponding to the L-level frame (queue) in the upstream direction is changed from one to two.

  The scheduler unit 1140 that operates based on the WRR method and is set based on the communication efficiency improvement setting data table T100C performs the following processing. In this case, it is assumed that the high priority frame is not stored in the H level queue (queue 1131), as in the first embodiment.

  The scheduler unit 1140 reads a maximum of two middle priority frames from the M level queue (queue 1132) at a time, and then continuously from the L level queue (queue 1133) at a time. Read up to two low priority frames. Here, it is assumed that many of the low-priority frames that the scheduler unit 1140 reads from the L-level queue are frames whose destination address (DA) is α, for example, as indicated by the aggregated data D200 in FIG. Note that, after reading the frame from the L-level queue, the scheduler unit 1140 repeats the process of reading the frame again in the order of the M and L-level queues.

  Therefore, the number (2) of medium priority frames read continuously by the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100C at a time is the scheduler unit 1140 set based on the reference setting data table T100. Is smaller than the number of medium priority frames (3) read continuously at a time.

  In addition, the number (2) of low-priority frames that the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100C continuously reads at a time is the scheduler unit 1140 set based on the reference setting data table T100. Is larger than the number (1) of low priority frames read continuously at a time.

  Thus, the low priority frame can be processed efficiently in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Further, based on the communication efficiency improvement setting data table T100C, the set scheduler unit 1140 performs the following processing.

  The scheduler unit 1140 sequentially transmits the medium priority frames read sequentially by the above processing to the transmission unit 1150 in a band of 4 Mbps or more and 800 Mbps or less. The transmission unit 1150 transmits the received medium priority frame to the server 50 in a band of 4 Mbps or more and 800 Mbps or less.

  In addition, the scheduler unit 1140 sequentially transmits the low-priority frames read sequentially by the above processing to the transmission unit 1150 in a band of 3 Mbps or more and 900 Mbps or less. The transmission unit 1150 transmits the received low priority frame to the server 50 in a band of 3 Mbps or more and 900 Mbps or less.

  Accordingly, the maximum allowable bandwidth (800 Mbps) for the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100C to transmit the medium priority frame is determined by the scheduler unit 1140 set based on the reference setting data table T100. It is smaller than the maximum allowable bandwidth (900 Mbps) for transmitting the medium priority frame. As a result, when the medium priority frame temporarily increases in a burst manner, the maximum allowable bandwidth is changed to a small value, so that instead of reducing the bandwidth for transmitting the medium priority frame, the low priority frame is changed. Sufficient bandwidth for transmission can be secured.

  In addition, the maximum allowable bandwidth (900 Mbps) for the scheduler unit 1140 set based on the communication efficiency improvement setting data table T100C to transmit the low priority frame is set by the scheduler unit 1140 set based on the reference setting data table T100. It is larger than the maximum allowable bandwidth (800 Mbps) for transmitting a low priority frame.

  By performing the above settings, the scheduler unit 1140 performs the first implementation when the medium priority frame temporarily increases in a burst manner and in a situation where many low priority frames must be processed. The low-priority frame can be processed more efficiently than when the setting change process in the above form or the setting change process A in the first modification of the first embodiment is performed alone. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Note that many of the frames transmitted to the server 50 are low-priority frames whose destination address (DA) is α. Therefore, when receiving the low priority frame whose destination address (DA) is α, the server 50 transmits the received low priority frame to the OLT 1000 capable of data communication with the PC 210.1 whose destination address (DA) is α. Therefore, by the above-described operations of the receiving unit 1310 and the classification unit 1320, many low-priority frames having a destination address (DA) of α are sequentially stored in the L-level queue (queue 1333) in the storage unit 1330.

  In the setting change process C in step S130C, the control unit 1400 further changes the setting of the scheduler unit 1340 based on the communication efficiency improvement setting data table T100C read from the storage unit 1500. Then, the process of step S130C ends.

  Of the various parameters of the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100C, the parameters changed from the various parameters of the scheduler unit 1340 set based on the reference setting data table T100 are M in the downlink direction. The minimum guaranteed bandwidth, the maximum allowable bandwidth and the weight corresponding to the frame (queue) of the level, and the minimum guaranteed bandwidth, the maximum allowable bandwidth and the weight corresponding to the frame (queue) of the L level in the downlink direction.

  The minimum guaranteed bandwidth corresponding to the M level frame (queue) in the downstream direction is changed from 5 Mbps to 4 Mbps. The maximum allowable bandwidth corresponding to the M level frame (queue) in the downlink direction is changed from 900 Mbps to 800 Mbps. The weight corresponding to the M level frame (queue) in the downstream direction is changed from three to two.

  The minimum guaranteed bandwidth corresponding to the downlink L level frame (queue) is changed from 1 Mbps to 3 Mbps. The maximum allowable bandwidth corresponding to the downlink L level frame (queue) is changed from 800 Mbps to 900 Mbps. The weight corresponding to the L level frame (queue) in the downlink direction is changed from one to two.

  The scheduler unit 1340 that operates based on the WRR method and is set based on the communication efficiency improvement setting data table T100C performs the following processing. In this case, as in the first embodiment, it is assumed that no high priority frame is stored in the H level queue (queue 1331).

  The scheduler unit 1340 reads a maximum of two middle priority frames from the M level queue (queue 1332) at a time, and then continuously from the L level queue (queue 1333) at a time. Read up to two low priority frames. Here, it is assumed that many of the low priority frames read by the scheduler unit 1340 from the L-level queue are frames whose destination address (DA) is α, for example, as indicated by the aggregated data D200 in FIG. Note that, after reading the frame from the L-level queue, the scheduler unit 1340 repeats the process of reading the frame again in the order of the M and L-level queues.

  Therefore, the number (2) of medium priority frames read continuously by the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100C at a time is the scheduler unit 1140 set based on the reference setting data table T100. Is smaller than the number of medium priority frames (3) read continuously at a time.

  Further, the number (2) of low priority frames that the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100C continuously reads at a time is the scheduler unit 1140 set based on the reference setting data table T100. Is larger than the number (1) of low priority frames read continuously at a time.

  Thus, the low priority frame can be processed efficiently in a situation where many low priority frames must be processed. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Further, based on the communication efficiency improvement setting data table T100C, the set scheduler unit 1340 performs the following processing.

  The scheduler unit 1340 sequentially transmits the medium priority frames read sequentially by the above processing to the transmission unit 1350 in a band of 4 Mbps or more and 800 Mbps or less. The transmission unit 1350 transmits the received medium priority frame to the frame destination via the logical path A in a band of 4 Mbps or more and 800 Mbps or less.

  In addition, the scheduler unit 1340 sequentially transmits the low-priority frames read sequentially by the above processing to the transmission unit 1150 in a band of 3 Mbps or more and 900 Mbps or less. The transmission unit 1350 transmits the received low-priority frame to the frame destination via the logical path A in a band of 3 Mbps or more and 900 Mbps or less.

  Accordingly, the maximum allowable bandwidth (800 Mbps) for the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100C to transmit the medium priority frame is determined by the scheduler unit 1340 set based on the reference setting data table T100. It is smaller than the maximum allowable bandwidth (900 Mbps) for transmitting the medium priority frame. As a result, when the medium priority frame temporarily increases in a burst manner, the maximum allowable bandwidth is changed to a small value, so that instead of reducing the bandwidth for transmitting the medium priority frame, the low priority frame is changed. Sufficient bandwidth for transmission can be secured.

  Also, the maximum allowable bandwidth (900 Mbps) for the scheduler unit 1340 set based on the communication efficiency improvement setting data table T100C to transmit the low priority frame is set by the scheduler unit 1340 set based on the reference setting data table T100. It is larger than the maximum allowable bandwidth (800 Mbps) for transmitting a low priority frame.

  By performing the above settings, the scheduler unit 1340 performs the first implementation in the case where the medium priority frame temporarily increases in a burst manner and in a situation where many low priority frames must be processed. The low-priority frame can be processed more efficiently than when the setting change process in the above form or the setting change process A in the first modification of the first embodiment is performed alone. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Referring to FIG. 11 again, when the process of step S130C is completed, the processes of steps S150, S160, and S162 are sequentially performed as in the first embodiment. If it is determined as YES in step S162, the process proceeds to step S170.

  In step S170, a setting change release process is performed as in the first embodiment. In the setting change canceling process, a process for restoring the setting changed in step S130C is performed. Specifically, the control unit 1400 sets the scheduler unit 1140 and the scheduler unit 1340 based on the reference setting data table T100 of FIG. 4A read from the storage unit 1500. Thereby, each setting of scheduler unit 1140 and scheduler unit 1340 is returned to the state before the setting change process in step S130C. Thereafter, the process of step S124 is performed again.

  As described above, in the present embodiment, when a situation where many low priority frames have to be processed, each of the scheduler unit 1140 and the scheduler unit 1340 continuously reads low priority frames. Set to increase the number. Thereby, a low priority frame can be processed efficiently. That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  Also, in this embodiment, when it becomes a situation where many low priority frames must be processed, each of scheduler unit 1140 and scheduler unit 1340 is set to reduce the maximum allowable bandwidth for transmitting medium priority frames. Each of the scheduler unit 1140 and the scheduler unit 1340 performs setting to increase the maximum allowable bandwidth for transmitting the low priority frame.

  By performing the above setting, each of the scheduler unit 1140 and the scheduler unit 1340 is used when the medium priority frame temporarily increases in a burst manner and in a situation where many low priority frames must be processed. Can process a low-priority frame more efficiently than when the setting change process of the first embodiment or the setting change process A of the first modification of the first embodiment is performed alone. . That is, even when it is necessary to process many frames with a low priority level for data transfer, there is an effect that high communication efficiency can be maintained.

  In the present invention, the various parameters of the scheduler unit 1140 and the scheduler unit 1340 are changed based on one communication efficiency improvement setting data table. However, the communication efficiency improvement setting data table for changing each parameter of the scheduler unit 1140 and the scheduler unit 1340 is not limited to one, and may be two or more.

  In the present invention, the minimum guaranteed bandwidth, the maximum allowable bandwidth, and the weight are simultaneously changed in various parameters of each of the scheduler unit 1140 and the scheduler unit 1340. However, the present invention is not limited to this. For example, only the weights may be changed in various parameters of the scheduler unit 1140 and the scheduler unit 1340. Further, for example, only the maximum allowable bandwidth may be changed in various parameters of each of the scheduler unit 1140 and the scheduler unit 1340.

  In the present invention, various parameters of the scheduler unit 1140 and the scheduler unit 1340 are changed based on the communication efficiency improvement setting data table. However, the present invention is not limited to this. For example, various parameters of the classification unit 1120 and the classification unit 1320 may be changed based on the communication efficiency improvement setting data table. In this case, the various parameters to be changed are the minimum guaranteed bandwidth and the maximum allowable bandwidth when the classification unit 1120 and the classification unit 1320 transmit frames received.

  For example, assume that the minimum guaranteed bandwidth and the maximum allowable bandwidth of the classification unit 1120 are set to 3 Mbps and 900 Mbps, respectively. In this case, the classification unit 1120 transmits the received frame in a band of 3 Mbps or more and 900 Mbps or less. As a result, the frame is stored in the corresponding queue in the storage unit 1130 at the rate at which the frame is transmitted.

  In the present invention, the various parameters of the scheduler unit 1140 and the scheduler unit 1340 and the various parameters of the classification unit 1120 and the classification unit 1320 are simultaneously changed based on the communication efficiency improvement setting data table. May be.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a figure which shows the structure of the communication system in this Embodiment. It is a block diagram which shows an example of an internal structure of OLT. It is a figure which shows the structure of a flame | frame. It is a figure which shows the setting data table as an example. It is a figure which shows the flowchart of a communication amount control process. It is a figure which shows total data as an example. It is a figure which shows the flowchart of the traffic control process A. It is a figure which shows the communication efficiency improvement setting data table as an example. It is a figure which shows the flowchart of the communication amount control process. It is a figure which shows the communication efficiency improvement setting data table as an example. It is a figure which shows the flowchart of the communication amount control process. It is a figure which shows the communication efficiency improvement setting data table as an example.

Explanation of symbols

  50 servers, 200.1, 200.2, 200.3 ONU, 210.1, 210.2, 210.3 PC, 1000 OLT, 1120, 1320 Classification unit, 1130, 1330, 1500 Storage unit, 1140 Scheduler Unit, 1400 control unit, 10000 communication system.

Claims (4)

Receiving means for receiving the frame;
Monitoring means for monitoring traffic of each of a plurality of frames having different data transfer priority levels received by the receiving means;
Transmitting means for transmitting the received frame based on a value of a predetermined parameter;
When the monitoring means does not detect the traffic of the priority level frame above the predetermined level, the value of the predetermined parameter is set to another value for increasing the traffic of the priority level frame less than the predetermined level. A communication device. The value of the predetermined parameter is a value restricted by a predetermined communication service quality rule,
The communication apparatus according to claim 1, wherein the other value set by the setting unit is a value that relaxes a value restricted by the predetermined communication service quality rule. The priority level less than the predetermined level includes a first level and a second level lower than the first level,
The communication device further includes storage means for storing the received frame,
The other values are a value for increasing the maximum allowable bandwidth at the time of transmission of the second level frame, a value for decreasing the maximum allowable bandwidth at the time of transmission of the first level frame, and the second level. A value that replaces the maximum allowable bandwidth at the time of transmission of the first frame with the maximum allowable bandwidth at the time of transmission of the first level frame, and the second level frame that the transmission means continuously reads from the storage means and transmits The communication device according to claim 1, wherein the communication device satisfies at least one value for increasing the number. A communication method performed by a communication device,
A receiving step for receiving the frame;
A monitoring step of monitoring traffic of each of a plurality of frames having different data transfer priority levels received by the reception step;
A transmission step of transmitting the received frame based on a value of a predetermined parameter;
When the monitoring step does not detect traffic of the priority level frame higher than a predetermined level, the value of the predetermined parameter is set to another value for increasing the traffic of the priority level frame lower than the predetermined level. A communication method comprising: a setting step.

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