JP2007184685A - Communication method and communication apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication method and a communication apparatus which can effectively utilize a band used by the communication apparatus. <P>SOLUTION: The communication method calculates a setup value associated with communication on the basis of a weight indicating a size of data transmitted at once to a concerned communication apparatus and set to each of a plurality of the communication apparatuses, discriminates whether or not the setup value satisfies a prescribed standard, and revises at least one of a plurality of the weights respectively corresponding to the apparatuses when the result of discrimination indicates that the setup value dose not satisfy the prescribed standard. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

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

  With the diversification of Internet services, there is an increasing need to transmit a plurality of traffic with different service 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. 2004-364059 (Patent Document 1), forward error correction (hereinafter also referred to as FEC (Forward Error Correction)) processing is performed according to the measured error rate, thereby reducing the throughput of the transmission path. Techniques for improving are 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, the SLA is the communication quality of communication such as the minimum communication speed of the line, the minimum guaranteed bandwidth of the line, the maximum guaranteed 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 Application Laid-Open No. 2002-135329 (Patent Document 2) and Japanese Patent Application Laid-Open No. 11-017690 (Patent Document 3) disclose techniques using the WRR method.

Japanese Patent Laid-Open No. 9-083547 (Patent Document 4) discloses a technique of a scheduler function that manages packet queue scheduling based on the accumulated amount of packet queues and the weight set for each packet queue (hereinafter, conventional). Technology A) is also disclosed.
JP 2004-364059 A JP 2002-135329 A JP-A-11-017690 Japanese Patent Laid-Open No. 9-083547

  However, in the prior art A, support for SLA is not considered in the management of packet queue scheduling. Therefore, in the prior art A, when trying to support SLA, there is a possibility that data communication cannot be performed normally with the setting value already set by the scheduler function.

  For this reason, there is a possibility that even if the prior art A is applied to the PON communication system, data communication cannot be performed normally. For this reason, there is a problem in that there is a possibility that the use band of the transmission path in the PON communication system may be wasted.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a communication method capable of effectively utilizing the band used by the apparatus.

  Another object of the present invention is to provide a communication device capable of effectively utilizing a band used by the device.

  In order to solve the above-described problem, according to one aspect of the present invention, a communication method performed by a communication device that performs data communication with a plurality of devices is transmitted to corresponding devices set for each of the plurality of devices at a time. A step of calculating a setting value related to communication based on a weight indicating a size of data to be performed, a step of determining whether or not the setting value satisfies a predetermined standard, and a step of determining that the predetermined standard is not satisfied And changing at least one of the plurality of weights respectively corresponding to the plurality of devices.

  According to the present invention, when the calculated setting value relating to communication does not satisfy a predetermined standard, the weight of the apparatus is adaptively changed. Therefore, there is an effect that the band used by the apparatus can be effectively utilized.

  Preferably, the method further includes a step of determining an increase / decrease in the number of devices performing data communication, and the step of changing includes a plurality of steps when it is determined that the number of devices performing data communication has increased / decreased in the step of determining increase / decrease Changing at least one of a plurality of weights respectively corresponding to the devices.

  According to the present invention, even if the number of devices performing data communication increases or decreases, the weight of the device is adaptively changed. Therefore, there is an effect that the band used by the apparatus can be effectively utilized.

  Preferably, the communication device performs data communication with a plurality of devices via a transmission line, the set value is a bandwidth value of the transmission line, and the calculating step is performed by the step of determining the increase / decrease of the device that performs data communication. If it is determined that the number has increased, a step of recalculating the band value based on the weight set for each of the plurality of devices and the increased device weight is included. If it is determined that the determined band value does not satisfy the predetermined standard, the increased device weight is decreased by recalculation so that the recalculated band value satisfies the predetermined standard.

  According to the present invention, if the bandwidth value of the transmission path recalculated when the number of devices for data communication is increased does not satisfy the predetermined standard, the increased device weight is set so that the bandwidth value satisfies the predetermined standard. Decrease by recalculation.

  Therefore, the optimum weight of the increased device can be obtained without adversely affecting the device to which the weight has already been set. As a result, it is possible to effectively utilize the bandwidth of the transmission path used by the increased number of devices.

  Preferably, the set value is a total value of delay times when data is transmitted between each of the plurality of devices and the communication device, the predetermined standard includes a standard of the delay time, and the step of calculating includes: When it is determined that the number of devices performing data communication has increased by the step of determining increase / decrease, the method includes a step of recalculating the total value based on the weight set for each of the plurality of devices and the increased device weight, In the calculating step, if it is determined in the determining step that the recalculated sum value does not satisfy the delay time standard, the recalculated sum value satisfies the delay time standard, and the plurality of devices Reducing the increased device weight and the weight set for each of the plurality of devices by recalculation so that the ratio of the corresponding plurality of weights and the increased device weight does not change. .

  According to the present invention, when the number of devices that perform data communication is increased, the total value of the delay times when data is transmitted between each of the plurality of devices and the communication device recalculated does not satisfy the delay time standard. In this case, the total value satisfies the delay time standard, and is set for each of the increased device weights and the plurality of devices so that the ratio of the plurality of weights corresponding to the plurality of devices and the increased device weight ratio does not change. Reduce the weight by recalculation.

  Therefore, there is an effect that it is possible to minimize the waste of the use band of the transmission path used by each of all apparatuses including the increased apparatus.

  According to another aspect of the present invention, a communication device that performs data communication with a plurality of devices communicates based on a weight that is set for each of the plurality of devices and indicates the size of data that is transmitted to the corresponding device at a time. A calculation unit that calculates a set value for the image, a determination unit that determines whether the set value satisfies a predetermined standard, and a determination unit that corresponds to a plurality of devices when it is determined that the predetermined standard is not satisfied Changing means for changing at least one of the plurality of weights.

  According to the present invention, when the calculated setting value relating to communication does not satisfy a predetermined standard, the weight of the apparatus is adaptively changed. Therefore, there is an effect that the band used by the apparatus can be effectively utilized.

  Preferably, the apparatus further includes an increase / decrease determination unit that determines increase / decrease in the number of devices that perform data communication, and the change unit determines that the increase / decrease determination unit determines that the number of devices that perform data communication has increased or decreased. At least one of a plurality of weights respectively corresponding to.

  According to the present invention, even if the number of devices performing data communication increases or decreases, the weight of the device is adaptively changed. Therefore, there is an effect that the band used by the apparatus can be effectively utilized.

  Preferably, the communication device performs data communication with a plurality of devices via a transmission line, the set value is a bandwidth value of the transmission line, and the calculation means increases the number of devices performing data communication by the increase / decrease determination means. If it is determined that the bandwidth value is recalculated on the basis of the weight set for each of the plurality of devices and the increased device weight, the calculating means determines that the recalculated bandwidth value is If it is determined that the value does not satisfy, the increased device weight is decreased by recalculation so that the recalculated band value satisfies a predetermined standard.

  According to the present invention, if the bandwidth value of the transmission path recalculated when the number of devices for data communication is increased does not satisfy the predetermined standard, the increased device weight is set so that the bandwidth value satisfies the predetermined standard. Decrease by recalculation.

  Therefore, the optimum weight of the increased device can be obtained without adversely affecting the device to which the weight has already been set. As a result, it is possible to effectively utilize the bandwidth of the transmission path used by the increased number of devices.

  Preferably, the set value is a total value of delay times when data is transmitted between each of the plurality of devices and the communication device, the predetermined standard includes a standard of the delay time, and the calculating means increases or decreases When it is determined by the determination means that the number of devices performing data communication has increased, the total value is recalculated based on the weight set for each of the plurality of devices and the increased device weight. When it is determined that the recalculated total value does not satisfy the delay time standard, the recalculated total value satisfies the delay time standard, and a plurality of weights and increments respectively corresponding to a plurality of devices. The weight of the increased device and the weight set for each of the plurality of devices are decreased by recalculation so that the ratio of the weights of the selected devices does not change.

  According to the present invention, when the number of devices that perform data communication is increased, the total value of the delay times when data is transmitted between each of the plurality of devices and the communication device recalculated does not satisfy the delay time standard. In this case, the total value satisfies the delay time standard, and is set for each of the increased device weights and the plurality of devices so that the ratio of the plurality of weights corresponding to the plurality of devices and the increased device weight ratio does not change. Reduce the weight by recalculation.

  Therefore, there is an effect that it is possible to minimize the waste of the use band of the transmission path used by each of all apparatuses including the increased apparatus.

  The communication method according to the present invention adaptively changes the weight of the device when the set value for the calculated communication does not satisfy a predetermined standard.

Therefore, there is an effect that the band used by the apparatus can be effectively utilized.
The communication apparatus according to the present invention adaptively changes the weight of the apparatus when the calculated setting value related to communication does not satisfy a predetermined standard.

  Therefore, there is an effect that the band used by the apparatus can be effectively utilized.

  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 1000 in the present embodiment. The communication system 1000 is, for example, the PON communication system described above. 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 1000 includes an OLT 100, ONUs 200.1, 200.2,. n (n: natural number) and an optical coupler 300.

  ONU 200.1, 200.2, ..., 200. The n and OLT 100 are devices based on the 1000BASE-PX10 standard of IEEE 802.3ah standard, for example. ONU 200.1, 200.2, ..., 200. n and the optical coupler 300 are connected by an optical fiber cable that is a transmission path.

  ONU 200.1, 200.2, ..., 200. Each of n is connected to, for example, a PC (Personal Computer). Note that ONU 200.1, 200.2,. The number of PCs connected to each of n is not limited to one, and a plurality of PCs may be used. Note that ONU 200.1, 200.2,. A device connected to each of n is not limited to a PC, and may be a dedicated terminal such as a set-top box or an IP telephone adapter and a router that bundles them.

  The optical coupler 300 and the OLT 100 are connected by an optical fiber cable that is a transmission path. The OLT 100 is connected to the network 50. The network 50 is an external network such as the Internet.

  Communication system 1000 is not limited to the configuration described above. For example, a configuration in which one terminal device and one control station device are connected by an optical fiber cable without using an optical coupler may be employed.

  In the following, the OLT 100 and the ONUs 200.1, 200.2,. Each of a plurality of routes through which data (hereinafter also referred to as a frame) between n is transmitted is also referred to as a logical path (channel). In the following, the OLT 100 and the ONUs 200.1, 200.2,. Data exchanged with each of n is also referred to as a frame. The OLT 100 includes ONU 200.1, 200.2,. Data communication is performed via a logical path formed between the terminal device to be communicated among n and the OLT 100. In the following, the OLT 100 and the ONU 200. A logical path between m (m: natural number) is expressed as a logical path m. For example, the logical path between the OLT 100 and the ONU 200.1 is the logical path 1.

  In the following, ONU 200.1, 200.2,. n is generally expressed as ONU200. Hereinafter, a logical path between the OLT 100 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 100 is also referred to as an uplink direction. The direction in which the frame is transmitted from the OLT 100 to the ONU 200 is also referred to as the downlink direction.

  FIG. 2 is a block diagram illustrating an example of the internal configuration of the OLT 100. Referring to FIG. 2, OLT 100 includes a communication unit 110A and a classification unit 130A.

  The communication unit 110A transmits and receives frames (data) to and from the network 50. The communication unit 110A transmits the frame received from the network 50 to the classification unit 130A.

  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 portion is a portion in which the destination of the frame and the MAC address of the transmission source of the frame are described. 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.

  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, the OLT 100 further includes a storage unit 140, a scheduler unit 130B, a control unit 120, an optical transmission / reception unit 110B, an interface unit 150, and a display unit 160.

  The storage unit 140 has a function of storing data in a nonvolatile manner. The storage unit 140 includes queues 142.1, 142.2, ..., 142, n. Here, the queue is a storage location for storing data (frames) provided in the storage unit 140. The queues 142.1, 142.2, ..., 142, n in the storage unit 140 are, for example, queues 142. The priority increases in the order of n to queue 142.1. That is, the queue 142. Frames with high priority are stored in the order of n to queue 142.1. That is, the frame with the highest priority is stored in the queue 142.1.

  The plurality of queues are queues 142. The priority is not limited to increasing in the order of n to queue 142.1. For example, the queue 142.1 to the queue 142. The priority may increase in the order of n.

  The control unit 120 has a function of controlling each unit in the OLT 100. The control unit 120 sets the classification unit 130A and the scheduler unit 130B. The control unit 120 may be any of a microprocessor, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), and other circuits having an arithmetic function. The control unit 120 operates as a management unit 122 and a setting unit 124. The management unit 122 controls each unit in the OLT 100. The setting unit 124 sets the classification unit 130A and the scheduler unit 130B.

  The classification unit 130A classifies the received frame. Specifically, the classification unit 130A stores the received frame in a queue in the storage unit 140 according to the priority of the received frame, for example, the TOS field, based on the setting of the control unit 120. For example, when the priority of the TOS field of the received frame is “7”, the classification unit 130A stores the received frame in the queue 142.1 in the storage unit 140.

  Based on the setting of the control unit 120, the scheduler unit 130B reads out the frames stored in the queue in order from the queue with the highest priority, and transmits the frames to the optical transmission / reception unit 110B.

  The optical transmission / reception unit 110B converts the frame received from the scheduler unit 130B into an optical signal, and transmits the optical signal to the ONU 200 that is the destination of the frame via the logical path A. In addition, the optical transceiver 110 </ b> B converts the received frame as an optical signal received from the ONU 200 via the logical path A into electrical digital data, and transmits the electrical digital data to the controller 120.

  The interface unit 150 is an interface for receiving an instruction input from an operator. The interface unit 150 is, for example, a keyboard. Information input by the operator using the interface unit 150 is transmitted to the control unit 120. Based on the information received from interface unit 150, control unit 120 sets classification unit 130A and scheduler unit 130B.

  The setting of the classification unit 130A is, for example, a setting in which queue the classification unit 130A stores frames based on the priority of received frames. The setting of the scheduler unit 130B is, for example, setting of which queue the frame is read from, and setting of the maximum size (hereinafter also referred to as weight) of the size of the frame (data) that the scheduler unit 130B reads at a time. is there. In the following, the destination of the frame (data) stored in the queue is the ONU 200. m, the maximum value of the frame size read from the queue at a time is set to ONU200. It is also called the weight of m. That is, the weight is the maximum value of the size of the frame (data) transmitted at a time to the device that is the destination of the frame (data).

  The display unit 160 has a function of displaying characters, images, and the like so that various information can be referred to by the operator. The display unit 160 displays an image based on the image data output from the control unit 120. The display unit 160 is a liquid crystal display (LCD (Liquid Crystal Display)), a CRT (Cathode Ray Tube) display, an FED (Field Emission Display), an organic EL display (Organic Electroluminescence Display), or other image display methods such as a dot matrix. Any of display devices may be used. Note that the display unit 160 may be connected to the OLT 100 as an external display device instead of the OLT 100.

  The OLT 100 shown in FIG. 2 has a configuration in which the optical transmission / reception unit 110B transmits a reception frame received from the ONU 200 via the logical path A to the network 50 via the communication unit 110A. Since it is not described in the processing, it is not particularly illustrated.

  In the present embodiment, it is assumed that, for example, 32 ONUs 200 are set in advance by an operator via OLT 100 and optical coupler 300 so that data communication is possible. The 32 ONUs 200 are represented as ONU 200.1, 200.2,.

  Next, band setting processing performed by the OLT 100 will be described. The band described in the present embodiment is a band of an optical fiber cable (hereinafter also referred to as band A) as a transmission line connecting the OLT 100 and the optical coupler 300. The bandwidth is classified into a guaranteed bandwidth and a non-guaranteed bandwidth. The guaranteed bandwidth of the bandwidth A is assumed to be bandwidth controlled by the aforementioned WRR method.

  Note that the maximum guaranteed bandwidth MaxBW of the bandwidth A is defined as 1 Gbps as an example by the aforementioned SLA. Further, it is assumed that the surplus bandwidth of the bandwidth A is equally distributed to the bandwidth of the logical path corresponding to each ONU. Further, it is assumed that the minimum guaranteed bandwidth MinBW of each of the logical paths 1 to 32 is defined as, for example, 20 Mbps by the SLA. That is, the minimum guaranteed bandwidth MinBW of the logical path corresponding to each of the ONUs 200.1 to 200.32 is 20 Mbps. The minimum guaranteed bandwidth MinBW [q (q: natural number)] indicates the minimum guaranteed bandwidth of the logical path q. Therefore, for example, the minimum guaranteed bandwidth MinBW [2] indicates the minimum guaranteed bandwidth of the logical path 2.

  Further, it is assumed that the weight for each of the ONUs 200.1, 200.2,..., 200.32 is set in advance to, for example, 10 kbytes by the operation of the interface unit 150 by the operator.

  The control unit setting unit 124 performs the above setting for the scheduler unit 130B. Therefore, since the weight for each of ONUs 200.1, 200.2,..., 200.32 is set to 10 kbytes, the scheduler unit 130B in which the above setting has been performed has the frames stored in the queue. For example, if the destination is ONU 200.1, the size of a frame read from the queue at a time is 10 kbytes at the maximum.

  The bandwidth A used by the scheduler unit 130B is set to 1 Gbps or less. Further, the bandwidth of the logical path corresponding to each of the ONUs 200.1 to 200.32 used by the scheduler unit 130B is set to 20 Mbps or more.

  In the communication system 1000 with the above conditions, when newly registering an ONU, for example, when adding one ONU weight, if the weight of the ONU that has already been set is increased, the ONU with the increased weight will not be in time for data reception processing May cause overflow. For this reason, in the present embodiment, the existing registered device environment is prevented from changing as much as possible. In order to realize this, in the present embodiment, when the minimum guaranteed bandwidth of the line defined by the above SLA is not satisfied, the weight of the new ONU is appropriately changed without changing the weight of the already set ONU. The bandwidth setting process is performed so that the minimum guaranteed bandwidth of the line defined by the above-mentioned SLA is satisfied by decreasing to a small value.

  A bandwidth setting process performed by the OLT 100 when a new ONU is newly registered in the communication system 1000 under the above conditions will be described. In the following, an ONU newly registered in the communication system 1000 is also referred to as a new ONU. In the present embodiment, the new ONU is expressed as ONU 200.33. Further, it is assumed that the minimum guaranteed bandwidth MinBW [33] of the logical path 33 is defined as 100 Mbps by the SLA. That is, the minimum guaranteed bandwidth MinBW [33] of the logical path 33 corresponding to the ONU 200.33 is 100 Mbps.

  FIG. 4 is a flowchart illustrating the bandwidth setting process. Referring to FIG. 4, in step S <b> 105, setting unit 124 determines whether there is an additional registration of ONU. If YES in step S105, the process proceeds to step S110. On the other hand, if NO at step S105, the process at step S105 is performed again.

  In step S110, a new ONU weight is input. Specifically, the operator inputs the weight of the new ONU using the interface unit 150. The weight of the input new ONU is, for example, 10 kbytes. Thereafter, the process proceeds to step S120.

In step S120, a new ONU allocated bandwidth (hereinafter also referred to as a new allocated bandwidth) is calculated. Specifically, the setting unit 124 calculates a new allocated bandwidth NEWBW by the following equation (1).
NEWWBW = W [k] / (W [1] + W [2] +... + W [n (n: total number of ONUs)]) × MaxBW (1)
Since the total number of ONUs in the communication system 1000 including the new ONU is 33, n = 33. Each of W [1] + W [2] +... + W [n] in Expression (1) Indicates the weight of i (i: natural number). W [k] in equation (1) is the weight of the new ONU. Since the new ONU is OUN200.33, k = 33. Therefore, when n = 33, k = 33, W [1] to W [33] = 10 kbytes, and MaxBW = 1 Gbps are substituted into Expression (1), the new allocated bandwidth NEWWBW is obtained from 10 k / 10 k × 33 × 1 Gbps. 30.3 Mbps. Thereafter, the process proceeds to step S122.

  In step S122, bandwidth allocation is performed. Specifically, the setting unit 124 allocates 20 Mbps, which is the minimum guaranteed bandwidth MinBW, to the bandwidth of the logical path corresponding to each of the ONUs 200.1 to 200.32. In addition, the setting unit 124 allocates the calculated new allocation bandwidth NEWBW (30.3 Mbps) to the logical path corresponding to the ONU 200.33. Thereafter, the process proceeds to step S124.

In step S124, a surplus bandwidth is calculated. Specifically, the setting unit 124 calculates the surplus bandwidth OVBW by the following equation (2).
OVBW = MaxBW− (total sum of allocated bandwidths of logical paths corresponding to each of ONU 200.1 to 200.n) (2)
Therefore, if MaxBW = 1 Gbps and n = 33 are substituted into the equation (2), the surplus bandwidth OVBW is 329.7 Mbps from 1 Gbps− (20 Mbps × 32 + 30.3 Mbps). In the present embodiment, as described above, the surplus bandwidth of the bandwidth A (1 Gbps) is evenly distributed to the bandwidth of the logical path corresponding to each ONU, so that the setting unit 124 sets the logical path corresponding to each ONU. The surplus bandwidth OVBWN is calculated by the following equation (3).
OVBWN = OVBW / n (3)
Therefore, when OVBW = 329.7 Mbps and n = 33 are substituted into Equation (3), the surplus bandwidth OVBWN is 9.99 Mbps from 329.7 Mbps / 33. Thereafter, the process proceeds to step S126.

In step S126, the actual allocated bandwidth SUBW is calculated. The actual allocated bandwidth is a bandwidth that is substantially allocated to the logical path corresponding to each of the ONUs 200.1 to 200.33. Specifically, the setting unit 124 calculates the actual allocated bandwidth SUBW by the following equation (4).
SUBW = logical path allocation band corresponding to ONU + OVBWN (4)
Therefore, when OVBWN = 9.99 Mbps is substituted into the equation (4), the actual allocated bandwidth SUBW of each of the ONUs 200.1 to 200.32 is 29.99 Mbps from 20 Mbps + 9.99 Mbps. Similarly, the actual allocated bandwidth SUBW of the ONU 200.33 is 40.29 Mbps from 30.3 Mbps + 9.99 Mbps. Thereafter, the process proceeds to step S130.

  In step S130, the setting unit 124 determines whether or not the actual allocated bandwidth of each of the ONUs 200.1 to 20.33 is equal to or greater than the corresponding minimum guaranteed bandwidth MinBW. That is, it is determined whether or not each of the ONUs 200.1 to 200.33 satisfies the minimum guaranteed bandwidth of the line defined by the SLA. If YES in step S130, the bandwidth setting process ends. On the other hand, if NO at step S130, the process proceeds to step S134.

  In the present embodiment, the actual allocated bandwidth SUBW of each of the ONUs 200.1 to 200.32 is 29.99 Mbps, and the minimum guaranteed bandwidth MinBW of the logical path corresponding to each of the ONUs 200.1 to 20.32 is 20 Mbps. It is. Therefore, the conditions of step S130 are satisfied for ONUs 200.1 to 200.32. On the other hand, the actual allocated bandwidth SUBW of the ONU 200.33 is 40.29 Mbps, and the minimum guaranteed bandwidth MinBW [33] of the logical path 33 corresponding to the ONU 200.33 is 100 Mbps. Therefore, the ONU 200.33 does not satisfy the condition of step S130. Therefore, it progresses to step S134.

  In the present embodiment, when the condition of step S130 is not satisfied, that is, when the minimum guaranteed bandwidth of the line defined by the SLA is not satisfied, the setting unit 124 displays the following warning on the display unit 160: The band setting process may be terminated by displaying an image. In this case, additional registration of a new ONU is not permitted.

  FIG. 5 is a diagram showing a warning image G100 as an example. Referring to FIG. 5, warning message G100 displays, for example, a warning message indicating that the minimum guaranteed bandwidth of the line defined by SLA is not satisfied and that ONU additional registration is not permitted. The message is, for example, a message “The line does not satisfy the minimum guaranteed bandwidth of the line defined by SLA. Additional registration of this ONU is not permitted”.

Referring to FIG. 4 again, in step S134, the necessary surplus bandwidth is calculated. First, in order to set the allocated bandwidth of the logical path 33 corresponding to the ONU 200.33 to 100 Mbps or more of the minimum guaranteed bandwidth MinBW [33], the setting unit 124 uses the following equation (5) to calculate the necessary surplus bandwidth of the bandwidth A. NEOVBW is calculated.
NEOVBW = MaxBW− (sum of minimum guaranteed bandwidth MinBW of logical path corresponding to each of ONU 200.1 to 200.n) (5)
Therefore, if MaxBW = 1 Gbps and n = 33 are substituted into Equation (5), the necessary surplus bandwidth NEOVBW is 260 Mbps from 1 Gbps− (20 Mbps × 32 + 100 Mbps). In the present embodiment, as described above, the surplus bandwidth (1 Gbps) of the bandwidth A is equally distributed to the bandwidth of the logical path corresponding to each ONU, so that the setting unit 124 sets the logical path corresponding to each ONU. The necessary surplus bandwidth NEOVBWN is calculated by the following equation (6).
NEOVBWN = NEOVBW / n (6)
Therefore, if NEOVBW = 260 Mbps and n = 33 are substituted into equation (6), the necessary surplus bandwidth NEOVBWN is 7.88 Mbps from 260 Mbps / 33. Thereafter, the process proceeds to step S136.

In step S136, the necessary allocated bandwidth for the new ONU is calculated. The necessary allocated bandwidth is a bandwidth that is allocated to a logical path corresponding to a new ONU in order to satisfy the minimum guaranteed bandwidth of a line defined by the above-mentioned SLA. Specifically, the setting unit 124 calculates the necessary allocated bandwidth NESUBW by the following equation (7).
NESUBW = Minimum guaranteed bandwidth MinBW-NEOVBWN of the logical path corresponding to the new ONU (7)
Therefore, if NEOVBWN = 7.88 Mbps is substituted into Equation (7), the necessary allocated bandwidth NESUBW is 92.12 Mbps from 100 Mbps−7.88 Mbps. Thereafter, the process proceeds to step S138.

In step S138, the new ONU weight is recalculated. Specifically, the setting unit 124 calculates the weight of the new ONU that satisfies the following formula (8).
W [k] / (W [1] + W [2] + ... + W [n]) × MaxBW ≧ NESUBW (8)
W [k] in Equation (8) is the weight of the new ONU. Since the new ONU is OUN200.33, k = 33. Therefore, when substituting NESUBW = 92.12 Mbps, n = 33, k = 33, W [1] to W [32] = 10 kbytes, MaxBW = 1 Gbps into equation (8), equation (8) becomes: Equation (9) is obtained.
W [33] / (10k × 32 + W [33]) × 1 Gbps ≧ 92.12 Mbps
... (9)
When Expression (9) is transformed so as to obtain W [33], the following Expression (10) is obtained.
W [33] ≧ 32.47 kbytes (10)
Therefore, the setting unit 124 rounds up the decimal point of W [33] and sets W [33] to 33 kbytes. Thereafter, the process proceeds to step S139.

  In step S139, the setting unit 124 sets the weight of the new ONU (ONU 200.33) to 33 kbytes. Thereafter, the process proceeds to step S140.

  In step S140, display processing is performed. In the display process, the setting unit 124 causes the display unit 160 to display the following setting completion image.

  FIG. 6 is a diagram illustrating a setting completion image G100A as an example. Referring to FIG. 6, setting completion image G100A includes, for example, the fact that the minimum guaranteed bandwidth of the line stipulated by SLA is satisfied, the fact that the weight of ONU to be additionally registered has been changed to an optimum value, and the addition A setting completion message indicating the registered ONU allocated bandwidth is displayed. The setting completion message is, for example, “The minimum guaranteed bandwidth of the line stipulated by the SLA is satisfied, and the weight of the newly added ONU is changed to an optimum value. The allocated bandwidth of the additionally registered ONU is 100 Mbps. Is the message.

  Referring to FIG. 4 again, when the process of step S140 ends, this band setting process ends. As a result, the weight of the new ONU is set such that the minimum guaranteed bandwidth of the line defined by the SLA is satisfied and the use bandwidth of the logical path corresponding to the new ONU does not waste.

  As described above, in this embodiment, the ONU weight already set is not changed, and the actual allocated bandwidth SUBW of the new ONU calculated based on the input weight of the new ONU is defined by the SLA. If the minimum guaranteed bandwidth of the existing line is not satisfied, the weight of the new ONU satisfies the minimum guaranteed bandwidth of the line specified by the SLA, and the use bandwidth of the logical path corresponding to the new ONU is not wasted. Recalculated to a correct value. Therefore, it is possible to effectively use the bandwidth of the logical path corresponding to the new ONU while preventing the already set ONU from overflowing.

<Second Embodiment>
In the first embodiment, the bandwidth setting process has been described so that the minimum guaranteed bandwidth of the line defined by the SLA is satisfied when an ONU is newly registered additionally. However, even if the minimum guaranteed bandwidth of the line is satisfied, the maximum delay time of the communication system defined by the SLA may not be satisfied.

  In the present embodiment, a process (hereinafter also referred to as setting process A) in which both the minimum guaranteed bandwidth of the line defined by the SLA and the maximum delay time of the communication system are satisfied will be described.

  Since the communication system in the present embodiment is similar to communication system 1000 in the first embodiment, detailed description will not be repeated. Since the OLT 100 is the same as that of the first embodiment, detailed description will not be repeated.

  In this embodiment, as in the first embodiment, it is assumed that, for example, 32 ONUs 200 are set in advance by the operator via the OLT 100 and the optical coupler 300 so that data communication is possible. Assume that the maximum guaranteed bandwidth MaxBW of the bandwidth A is defined as 1 Gbps as an example by the aforementioned SLA. Further, it is assumed that the surplus bandwidth of the bandwidth A is equally distributed to the bandwidth of the logical path corresponding to each ONU.

  Further, it is assumed that the minimum guaranteed bandwidth MinBW of each of the logical paths 1 to 32 is defined as, for example, 20 Mbps by the SLA. That is, the minimum guaranteed bandwidth MinBW of the logical path corresponding to each of the ONUs 200.1 to 200.32 is 20 Mbps. In addition, it is assumed that the weight for each of the ONUs 200.1, 200.2,..., 200.32 is set to 11 kbytes in advance by the operator's operation.

  The control unit setting unit 124 performs the above setting for the scheduler unit 130B. Therefore, since the weight for each of ONUs 200.1, 200.2,..., 200.32 is set to 11 kbytes, the scheduler unit 130B in which the above setting has been performed has the frames stored in the queue. For example, if the destination is ONU 200.1, the size of the frame that is read from the queue at a time is 11 kbytes at the maximum.

  The bandwidth A used by the scheduler unit 130B is set to 1 Gbps or less. Further, the bandwidth of the logical path corresponding to each of the ONUs 200.1 to 200.32 used by the scheduler unit 130B is set to 20 Mbps or more.

  In this embodiment, when a new ONU is registered, for example, in the communication system 1000 under the above conditions, for example, the minimum guaranteed bandwidth of the line and the maximum delay time of the communication system defined by the above SLA are satisfied. Thus, processing (hereinafter also referred to as setting processing A) is performed. Assume that the maximum delay time MaxDelay of the communication system 1000 is defined as 3.0 msec by the SLA, for example. The condition for satisfying the maximum delay time of the communication system defined by the SLA is that the maximum delay time MaxDelay of the communication system 1000 is equal to or less than the sum of the maximum delay times of each ONU, which will be described later. If the maximum delay time of the communication system defined by the SLA is not satisfied, there is a high possibility that data communication cannot be performed normally in the communication system 1000.

  A setting process A performed by the OLT 100 when a new ONU is additionally registered in the communication system 1000 under the above conditions will be described. In the following, an ONU newly registered in the communication system 1000 is also referred to as a new ONU as described above. The new ONU is represented as ONU 200.33. Further, it is assumed that the minimum guaranteed bandwidth MinBW [33] of the logical path 33 is defined as 100 Mbps by the SLA. That is, the minimum guaranteed bandwidth MinBW [33] of the logical path corresponding to the ONU 200.33 is 100 Mbps.

  FIG. 7 is a flowchart of the setting process A. Referring to FIG. 7, in step S <b> 202, setting unit 124 determines whether there is an additional registration of ONU. If YES in step S202, the process proceeds to step S203. On the other hand, if NO at step S202, the process at step S202 is performed again.

  In step S203, a new ONU weight is input. Specifically, the operator inputs the weight of the new ONU using the interface unit 150. The weight of the input new ONU is, for example, 50 kbytes. Thereafter, the process proceeds to step S204.

In step S204, the maximum delay time is calculated. Specifically, the setting unit 124 calculates the maximum delay time DT [p (p: natural number)] of each of the ONUs 200.1, 200.2,. To do. Here, the ONU maximum delay time is the time required for the round trip of data (frame) between the OLT and the ONU. For example, the maximum delay time of the ONU 200.1 is the time required for the round trip of data (frame) between the OLT 100 and the ONU 200.1. Note that DT [p] is ONU200. The maximum delay time of p is shown.
DT [p] = W [p] / (MaxBW) (11)
When W [p] = 11k and MaxBW = 1 Gbps are substituted into equation (11), the maximum delay time DT [p] is 88 μsec from 11 × 1000 × 8 / (1000 × 10 ⁶ ). Note that 11 × 1000 × 8 is multiplied by 8 to convert it into bits. Therefore, the maximum delay time DT [p] of each of the ONUs 200.1, 200.2,..., 200.32 is 88 μsec.

Next, the setting unit 124 calculates the maximum delay time DT [33] of the ONU 200.33 using Expression (11). Substituting p = 33, W [33] = 50 kbytes, and MaxBW = 1 Gbps into equation (11), the maximum delay time DT [33] of ONU 200.33 is 50 × 1000 × 8 / (1000 × 10 ⁶ ). Thus, 400 μsec is obtained.

Next, the setting unit 124 calculates the actual maximum delay time SYSDT of the communication system 1000 by the following equation (12).
SYSDT = DT [1] + DT [2] +... + DT [n (n: total number of ONUs)] (12)
Since the total number of ONUs in the communication system 1000 including the new ONU is 33, n = 33. Substituting n = 33, DT [1] to DT [32] = 88 μsec, and DT [32] = 400 μsec into the equation (12), the real maximum delay time SYSDT is 88 μsec × 32 + 400 μsec. 216 milliseconds (3216 microseconds). Thereafter, the process proceeds to step S206.

  In step S206, the setting unit 124 determines whether or not the actual maximum delay time SYSDT of the communication system 1000 is equal to or less than the maximum delay time MaxDelay of the communication system 1000 defined by the SLA. If YES in step S206, the setting process A ends. On the other hand, if NO at step S206, the process proceeds to step S234.

  In the present embodiment, the actual maximum delay time SYSDT of the communication system 1000 is 3.216 ms, and the maximum delay time MaxDelay of the communication system 1000 defined by the SLA is 3.0 ms as described above. is there. Therefore, the condition of step S206 is not satisfied. Therefore, the process proceeds to step S234.

  In the present embodiment, when the condition of step S206 is not satisfied, that is, when the maximum delay time MaxDelay of the communication system 1000 defined by the SLA is not satisfied, the setting unit 124 displays the following on the display unit 160: Such a warning image may be displayed and the setting process A may be terminated. In this case, additional registration of a new ONU is not permitted.

  FIG. 8 is a diagram showing a warning image G200 as an example. Referring to FIG. 8, warning message G800 displays, for example, a warning message indicating that the maximum delay time of the communication system defined by SLA is not satisfied and that ONU additional registration is not permitted. . The message is, for example, a message “The communication system does not satisfy the maximum delay time defined by the SLA. Additional registration of this ONU is not permitted”.

  Again referring to FIG. 7, in step S234, the necessary surplus bandwidth is calculated. First, in order to set the allocated bandwidth of the logical path 33 corresponding to the ONU 200.33 to 100 Mbps or more of the minimum guaranteed bandwidth MinBW [33] defined by the SLA, the setting unit 124 uses the above-described equation (5), The necessary surplus band NEOVBW of band A is calculated. The necessary surplus bandwidth NEOVBWN is 7.88 Mbps by the same calculation as in step S134 described above. Thereafter, the process proceeds to step S236.

  In step S236, the necessary allocated bandwidth for the new ONU is calculated. The necessary allocated bandwidth NESUBW is 92.12 Mbps by the same calculation as in step S136 described above. Thereafter, the process proceeds to step S238.

  In step S238, the new ONU weight is recalculated. In step S238, the same calculation as in step S138 described above is performed, and an expression of W [33] ≧ 32.47 kbytes is calculated. Then, the setting unit 124 rounds up the decimal point of W [33] and sets W [33] to 33 kbytes. Thereafter, the process proceeds to step S239.

In step S239, the maximum delay time is calculated. Specifically, the setting unit 124 calculates the maximum delay time DT [33] of the new ONU (ONU200.33) according to the above equation (11). By substituting p = 33, W [33] = 33 kbytes, and MaxBW = 1 Gbps into Equation (11), the maximum delay time DT [33] of ONU 200.33 is 33 × 1000 × 8 / (1000 × 10 ⁶ ). Thus, 264 μsec.

Next, the setting unit 124 calculates the actual maximum delay time SYSDT of the communication system 1000 according to the above equation (12).
By substituting n = 33, DT [1] to DT [32] = 88 μsec, and DT [32] = 264 μsec into the equation (12), the actual maximum delay time SYSDT is calculated from 88 μsec × 32 + 264 μsec. This is 08 milliseconds (3080 microseconds). Thereafter, the process proceeds to step S240.

  In step S240, the setting unit 124 determines whether the actual maximum delay time SYSDT of the communication system 1000 is equal to or less than the maximum delay time MaxDelay of the communication system 1000 defined by the SLA. If YES in step S240, the setting process A ends. On the other hand, if NO at step S240, the process proceeds to step S252.

  In the present embodiment, the recalculated actual maximum delay time SYSDT of the communication system 1000 is 3.08 msec, and the maximum delay time MaxDelay of the communication system 1000 defined by the SLA is 3 as described above. 0.0 ms. Therefore, the condition of step S240 is not satisfied. That is, in the present embodiment, as in the first embodiment, simply changing the weight of the new ONU does not fall below the maximum delay time of the communication system defined by the SLA.

  Therefore, it is necessary to change the weights of the already registered ONUs 200.1 to 200.32. It should be noted that the weights of ONUs 200.1 to 200.33 are changed without changing the ratios of a plurality of weights and new ONUs (ONUs 200.33) respectively corresponding to the already registered ONUs 200.1 to 200.32. To do.

  In the present embodiment, when the condition of step S240 is not satisfied, that is, when the maximum delay time MaxDelay of the communication system 1000 defined by the SLA is not satisfied, the setting unit 124 displays the display unit 160 as described above. The setting image A may be terminated by displaying the warning image G200. In this case, additional registration of a new ONU is not permitted.

In step S252, the weight change coefficient α is calculated. Specifically, the setting unit 124 calculates the weight change coefficient α by the following equation (13) obtained by multiplying the maximum delay time of each ONU by α.
α (W [1] + W [2] +... + W [n (n: total number of ONUs)]) / MaxBW = MaxDelay (13)
When the equation (13) is transformed so as to obtain α, the following equation (14) is obtained.
α = MaxDelay × MaxBW / (W [1] + W [2] +... + W [n (n: total number of ONUs)]) (14)
When MaxDelay = 3.0 msec, MaxBW = 1 Gbps, n = 33, W [1] to W [32] = 11 kbytes, and W [33] = 50 kbytes are substituted into equation (14), the weight change coefficient α is It becomes 0.933 from 3 × 10 ⁻³ × 1000 × 10 ⁶ / (11 × 10 ³ × 8 × 32 + 50 × 10 ³ × 8). Thereafter, the process proceeds to step S254.

  In step S254, the ONU weight is recalculated. Specifically, the setting unit 124 multiplies each weight of W [1], W [2],..., W [n (n: total number of ONUs)] by α. Accordingly, W [1] to W [32] are 10.26 kbytes from 11 kbytes × 0.933. W [33] is 46.65 kbytes from 50 kbytes × 0.933. Then, the setting unit 124 rounds down the decimal places of W [1] to W [32] and sets W [1] to W [32] to 10 kbytes. Similarly, the setting unit 124 rounds down the decimal point of W [33] and sets W [33] to 46 kbytes. Thereafter, the process proceeds to step S259.

  In step S259, the setting unit 124 changes the weight setting of the ONUs 200.1 to 20.32 from 11 kbytes to 10 kbytes. In addition, the setting unit 124 changes the weight setting of the new ONU (ONU 200.33) from 50 kbytes to 46 kbytes. Thereafter, the process proceeds to step S260.

  In step S260, a display process is performed. In the display process, the setting unit 124 causes the display unit 160 to display the following setting completion image.

  FIG. 9 is a diagram showing a setting completion image G200A as an example. Referring to FIG. 9, setting completion image G200A shows, for example, that both the minimum guaranteed bandwidth of the line defined by the SLA and the maximum delay time of the communication system are satisfied, and the weight of each ONU after being changed A setting completion message is displayed. The setting completion message is, for example, “a setting that satisfies both the minimum guaranteed bandwidth of the line defined by the SLA and the maximum delay time of the communication system. The weight after the change of each ONU is ONU2000.1-200.32 Is 10 kbytes, and the weight of the additionally registered ONU 200.33 is 46 kbytes ”.

  Referring to FIG. 7 again, when the process of step S260 ends, this setting process A ends. As a result, the weight of each ONU that satisfies both the minimum guaranteed bandwidth of the line defined by the SLA and the maximum delay time of the communication system and minimizes the waste of the bandwidth used for the logical path corresponding to each ONU. Is set.

  As described above, in this embodiment, the weight of each ONU is satisfied if the minimum guaranteed bandwidth of the line specified by the SLA is satisfied but the maximum delay time of the communication system specified by the SLA is not satisfied. Without changing the ratio, the weight of each ONU is recalculated so as to satisfy the maximum delay time of the communication system defined by the SLA. Therefore, both the minimum guaranteed bandwidth of the line defined by the SLA and the maximum delay time of the communication system can be satisfied, and the waste of the used bandwidth of the logical path corresponding to each ONU can be minimized.

<Third Embodiment>
In the first and second embodiments, the processing for adding a new ONU has been described. In the present embodiment, a process will be described in the case where the ONU is deregistered from the communication system 1000 in a state where a plurality of ONUs are already set.

  Since the communication system in the present embodiment is similar to communication system 1000 in the first embodiment, detailed description will not be repeated. Since the OLT 100 is the same as that of the first embodiment, detailed description will not be repeated.

  In the present embodiment, it is assumed that, for example, eleven ONUs 200 are set in advance via the OLT 100 and the optical coupler 300 so that data communication is possible. Assume that the maximum guaranteed bandwidth MaxBW of the bandwidth A is defined as 1 Gbps as an example by the aforementioned SLA. Further, it is assumed that the surplus bandwidth of the bandwidth A is equally distributed to the bandwidth of the logical path corresponding to each ONU.

Further, it is assumed that the minimum guaranteed bandwidth MinBW of each of the logical path 1 to the logical path 11 is defined as 20 Mbps by the SLA, for example. That is, the minimum guaranteed bandwidth MinBW of the logical path corresponding to each of the ONUs 200.1 to 200.11 is 20 Mbps. In addition, it is assumed that the weight for each of the ONUs 200.1, 200.2,... In the above setting, it is assumed that both the minimum guaranteed bandwidth of the line defined by the SLA and the maximum delay time of the communication system are satisfied. Further, it is assumed that the following expression (15) is also satisfied.
W [s] / (W [1] + W [2] +... + W [n (n: total number of ONUs)]) × MaxBW ≧ MinBW [s (s: any value in the range of 1 to n)]・ (15)
The control unit setting unit 124 performs the above setting for the scheduler unit 130B. The bandwidth A used by the scheduler unit 130B is set to 1 Gbps or less. Further, the bandwidth of the logical path corresponding to each of the ONUs 200.1 to 200.11 used by the scheduler unit 130B is set to 20 Mbps or more.

  In the present embodiment, among the 11 ONUs set in the communication system 1000 with the above conditions, for example, a process for deregistering one ONU from the communication system 1000 (hereinafter referred to as setting process B). Say). Assume that the maximum delay time MaxDelay of the communication system 1000 is defined as 3.0 msec by the SLA, for example. As described above, the condition that satisfies the maximum delay time of the communication system defined by the SLA is that the maximum delay time MaxDelay of the communication system 1000 is equal to or less than the sum of the maximum delay times of each ONU.

  A setting process B performed by the OLT 100 when the registration of one ONU is canceled in the communication system 1000 under the above conditions will be described.

  FIG. 10 is a flowchart of the setting process B. Referring to FIG. 10, in step S <b> 302, setting unit 124 determines whether there is an ONU deregistration. The ONU registration is canceled by the operator using the interface unit 150. If YES in step S302, the process proceeds to step S310. On the other hand, if NO at step S302, the process at step S302 is performed again. In this embodiment, as an example, it is assumed that ONU 200.11 is deregistered.

In step S310, the weight of each ONU is recalculated. Specifically, the setting unit 124 calculates the weights of the ONUs 200.1, 200.2,..., 200.10 according to the following equation (16).
W [1]: W [2]: ...: W [n] = MinBW [1]: MinBW [2]: ...: MinBW [n] (16)
In Formula (16), MinBW [q] is ONU200. The minimum guaranteed bandwidth of the logical path q corresponding to q is shown. Since the registration of one ONU is canceled from 11 ONUs, n is changed from 11 to 10. In Expression (16), W [1] to W [11] are 10 kbytes, and MinBW [1] to MinBW [11] are 20 Mbps. That is, the ratio of the weights W [1] to W [11] is 1: 1:. Therefore, the weight W [11] of the ONU 200.11 to be deregistered is evenly distributed to the remaining ONUs (W [1] to W [10]). Therefore, when W [11] is divided by 10, it becomes 1 kbyte from 10 kbytes / 10.

  Therefore, a weight of 1 kbyte is added to each of W [1] to W [10]. As a result, the weight of each of W [1] to W [10] becomes 11 k bytes from 10 k bytes + 1 k bytes. When the weights of W [1] to W [11] are different, the weights distributed to the remaining ONUs are also based on the formula (16). Thereafter, the process proceeds to step S319.

  In step S319, the setting unit 124 changes the weight setting of the ONUs 200.1 to 200.10 from 10 kbytes to 11 kbytes. Thereafter, the process proceeds to step S320.

  In step S320, display processing is performed. In the display process, the setting unit 124 causes the display unit 160 to display the following setting completion image.

  FIG. 11 is a diagram illustrating a setting completion image G300 as an example. Referring to FIG. 11, in setting completion image G300, for example, both the minimum guaranteed bandwidth of the line defined by SLA and the maximum delay time of the communication system are satisfied, and the weight of each ONU is changed. And a setting completion message indicating the weight of each ONU after the change. The setting completion message is, for example, “The weight of each ONU was changed while satisfying both the minimum guaranteed bandwidth of the line prescribed by SLA and the maximum delay time of the communication system. Is a weight of 11 kbytes ”.

  Referring to FIG. 10 again, when the process of step S320 ends, this setting process B ends. As a result, the weight of each ONU is set so that both the minimum guaranteed bandwidth of the line defined by the SLA and the maximum delay time of the communication system are satisfied, and the use bandwidth of the logical path corresponding to each ONU does not waste. Is done.

  As described above, in the present embodiment, the weight of each ONU is recalculated so as to satisfy the maximum delay time of the communication system defined by the SLA without changing the weight ratio of each ONU.

  Therefore, both the minimum guaranteed bandwidth of the line defined by the SLA and the maximum delay time of the communication system can be satisfied, and the bandwidth of the logical path corresponding to each ONU can be effectively utilized.

  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 flowchart of a band setting process. It is a figure which shows the warning image as an example. It is a figure which shows the setting completion image as an example. It is a figure which shows the flowchart of the setting process A. It is a figure which shows the warning image as an example. It is a figure which shows the setting completion image as an example. It is a figure which shows the flowchart of the setting process. It is a figure which shows the setting completion image as an example.

Explanation of symbols

  100 OLT, 110B optical transmission / reception unit, 120 control unit, 124 setting unit, 130A classification unit, 130B scheduler unit, 140 storage unit, 150 interface unit, 160 display unit, 200.1, 200.2,. 200. n ONU, 1000 communication system.

Claims (8)

A communication method performed by a communication device that performs data communication with a plurality of devices,
Calculating a setting value for communication based on a weight set for each of the plurality of devices and indicating a size of data to be transmitted to the corresponding device at a time;
Determining whether the set value satisfies a predetermined standard;
And a step of changing at least one of a plurality of weights respectively corresponding to the plurality of devices when it is determined by the determining step that the predetermined standard is not satisfied. Further comprising determining an increase or decrease in the number of devices performing data communication;
The step of changing includes a step of changing at least one of a plurality of weights respectively corresponding to the plurality of devices when it is determined in the step of determining the increase / decrease that the number of devices performing the data communication has increased / decreased. The communication method according to claim 1, comprising: The communication device performs data communication with the plurality of devices via a transmission path,
The set value is a band value of the transmission path,
The calculating step is based on the weight set for each of the plurality of devices and the increased device weight when it is determined that the number of devices performing the data communication has increased by the step of determining the increase / decrease Recalculating the band value,
In the calculating step, when it is determined by the determining step that the recalculated band value does not satisfy the predetermined standard, the recalculated band value satisfies the predetermined standard, The communication method according to claim 2, comprising the step of reducing the increased device weight by recalculation. The set value is a total value of delay times when data is transmitted between each of the plurality of devices and the communication device,
The predetermined standard includes a delay time standard,
The calculating step is based on the weight set for each of the plurality of devices and the increased device weight when it is determined that the number of devices performing the data communication has increased by the step of determining the increase / decrease Recalculating the sum value,
In the calculating step, when the determining step determines that the recalculated sum value does not satisfy the delay time standard, the recalculated sum value satisfies the delay time standard; Further, the increased device weight and the weight set for each of the plurality of devices are decreased by recalculation so that the ratio of the plurality of weights respectively corresponding to the plurality of devices and the increased device weight ratio does not change. The communication method according to claim 2, comprising steps. A communication device that performs data communication with a plurality of devices,
Calculation means for calculating a setting value related to communication based on a weight set for each of the plurality of devices and indicating a size of data to be transmitted to the corresponding device at a time;
Determination means for determining whether the set value satisfies a predetermined standard;
A communication device comprising: a changing unit that changes at least one of a plurality of weights respectively corresponding to the plurality of devices when the determination unit determines that the predetermined standard is not satisfied. It further comprises an increase / decrease determination means for determining an increase / decrease in the number of devices performing data communication,
The change unit changes at least one of a plurality of weights respectively corresponding to the plurality of devices when the increase / decrease determination unit determines that the number of devices performing the data communication has increased or decreased. The communication apparatus as described in. The communication device performs data communication with the plurality of devices via a transmission path,
The set value is a band value of the transmission path,
When the increase / decrease determination unit determines that the number of devices performing the data communication has increased, the calculation unit determines the band value based on the weight set for each of the plurality of devices and the increased device weight. Recalculate
When the determination unit determines that the recalculated band value does not satisfy the predetermined standard, the calculating unit increases the increase so that the recalculated band value satisfies the predetermined standard. The communication device according to claim 6, wherein the weight of the selected device is reduced by recalculation. The set value is a total value of delay times when data is transmitted between each of the plurality of devices and the communication device,
The predetermined standard includes a delay time standard,
When the increase / decrease determination unit determines that the number of devices that perform the data communication has increased, the calculation unit determines the total value based on the weight set for each of the plurality of devices and the increased device weight Recalculate
When the determining means determines that the recalculated sum value does not satisfy the delay time standard, the recalculated sum value satisfies the delay time standard; and The increased device weight and the weight set for each of the plurality of devices are decreased by recalculation so that the ratio of the plurality of weights corresponding to the plurality of devices and the increased device weight ratio do not change. Item 7. The communication device according to Item 6.

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