JP2009010530A - Communication equipment and optical communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide communication equipment on the station side for fairly allocating bands to each subscriber side communication equipment in an optical communication system for adaptively changing the redundancy of an error correction code to be imparted to transmission data corresponding to a connection distance. <P>SOLUTION: The communication equipment on the station side for transmitting and receiving data to which the error correction code of the redundancy individually determined for each subscriber side communication equipment is imparted to/from the subscriber side communication equipment is provided with: a communication request information terminating part (18) for acquiring the information of the data amount of up data whose transmission is desired from each subscriber side communication equipment; and a band allocation control part (11) for determining the band to be allocated to each subscriber side communication equipment on the basis of the received information and the redundancy. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a station-side communication apparatus that fairly allocates a band for transmitting uplink data to a plurality of subscriber-side communication apparatuses in an optical communication system.

  Broadband FTTH systems for subscribers using optical fiber are entering full-scale use. There are a plurality of FTTH (Fiber To The Home) systems, one of which is a GE-PON (Gigabit Ethernet (registered trademark)-Passive Optical Network) system which is a communication system using Ethernet (registered trademark) frames. There is. In addition, there are A-PON (ATM-PON) and B-PON (Broadband-PON), which are communication using ATM (Asynchronous Transfer Mode) packets, but a system that can directly accommodate Ethernet (registered trademark) from a communication system using ATM packets. Is more popular because it can be realized at low cost.

  Also, studies are being conducted on services that are multiplexed and transmitted with an optical video transmission system that transmits video analog signals to a GE-PON system, which is one of the broadband FTTH systems.

  In the FTTH GE-PON system, a plurality of subscriber side communication devices (ONU: Optical Network Unit) and a station side communication device (OLT: Optical Line Terminal) are connected via an optical fiber cable via a star coupler. Further, this GE-PON system complies with the following Non-Patent Document 1, and the FEC (Forward Error Correction) function that has been conventionally used is also defined in Non-Patent Document 1.

IEEE (Institute of Electrical and Electronics Engineers) 802.3ah

  Here, when the FEC function conforming to the non-patent document 1 (IEEE802.3ah) is mounted and operated on the FTTH GE-PON system, the FEC strength of all ONUs under the same PON is constant, so the long distance ONU When the is connected, the FEC strength that matches the farthest ONU is required. This means that the FEC redundancy code unnecessary for the near-end ONU is forced and the transmission efficiency is lowered.

  Therefore, a method has been proposed in which an extended function for changing the FEC redundancy according to the connection distance of the ONU is also implemented and operated to improve transmission efficiency. However, when this extended function is implemented, the transmission efficiency can be improved, but there is a problem that the ONU having a longer connection distance has a higher FEC redundancy and the usable bandwidth is lower than that of the short-distance connection ONU. That is, even if the same bandwidth is allocated to a plurality of ONUs, the actual bandwidth that each ONU can use for data transmission differs if the data amount of the FEC redundancy code assigned to the transmission data by each ONU is different. It cannot be said that they are allocated fairly.

  The present invention has been made in view of the above, and the FEC redundancy is different in an optical communication system that adaptively changes the redundancy of a redundant code added to transmission data in accordance with the connection distance between communication devices. It is an object of the present invention to obtain a communication device (OLT) that assigns user use bands fairly to ONUs, that is, a plurality of ONUs having different connection distances.

  In order to solve the above-described problems and achieve the object, the present invention forms a PON system together with a plurality of subscriber-side communication devices for time-division multiplex transmission of uplink data, and each subscriber-side communication device individually A station-side communication device that transmits / receives data with an error correction code of the determined redundancy to / from the subscriber-side communication device, from each of the subscriber-side communication devices. Communication request information acquisition means for acquiring data amount information of data, and allocation to each subscriber side communication device based on the data amount information of the uplink data acquired by the communication request information acquisition means and the redundancy Band allocation control means for determining a band for uplink data transmission.

  According to the present invention, the communication device (OLT) on the station side determines each ONU based on the capacity of the data that each subscriber communication device (ONU) desires to communicate and the redundancy of the redundant code added to the data. Since the bandwidth allocated to each ONU is determined, the bandwidth can be allocated to each ONU fairly even if the redundancy of the redundant code assigned to the transmission data is different. .

  Embodiments of a communication apparatus and an optical communication system according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a diagram illustrating a configuration example of a first embodiment of a communication system including a communication device according to the present invention. This communication system includes an intra-station device (OLT: Optical Line Terminal) 1 that is a communication device on the station side and a plurality of subscriber devices (ONU: Optical Network Unit) 2-1 to 2-3 that are communication devices on the subscriber side. The OLT 1 and each ONU (ONUs 2-1 to 2-3) are connected by an optical fiber 4 via an optical coupler 3. Hereinafter, the ONUs 2-1 to 2-3 are collectively referred to as ONU2. Downlink data transmitted from the OLT 1 toward each ONU 2 is broadcasted, and uplink data transmitted from each ONU toward the OLT 1 is transmitted in time division multiplex burst.

  FIG. 2 is a diagram illustrating a configuration example of the in-station device (OLT) 1 according to the first embodiment. The OLT 1 includes a bandwidth allocation control unit 11, a communication permission information generation unit 12, a MUX unit 13, a downlink frame buffer unit 14, an FEC control information termination unit 15, an FEC encoding unit 16, and an optical / electrical conversion unit 17. A communication request information termination unit 18 and an FEC information management table holding unit 19.

  The band allocation control unit 11 determines the uplink data transmission band to be allocated to each ONU 2. The communication permission information generation unit 12 generates transmission permission information for notifying the ONU 2 desiring to transmit uplink data of the time and period during which transmission is permitted. The MUX unit 13 multiplexes and outputs a plurality of information input from different paths. The downlink frame buffer unit 14 holds a downlink data frame to be transmitted to the ONU 2. The FEC control information termination unit 15 determines the redundancy (FEC redundancy) of the redundant code (FEC parity) added to the data transmitted / received to / from each ONU 2. The FEC encoding unit 16 performs FEC encoding on the input information and outputs it. The optical / electrical converter 17 converts the input optical signal into an electrical signal, and converts the optical signal into an optical signal when the electrical signal is input. The communication request information termination unit 18 acquires the communication request information transmitted from each ONU 2.

  FIG. 3 is a diagram illustrating a configuration example of the subscriber unit (ONU) 2 according to the first embodiment. The ONU 2 includes an optical / electric conversion unit 21, an FEC encoding unit 22, a communication permission information termination unit 23, an FEC control information termination unit 24, an upstream frame buffer unit 25, a communication request information generation unit 26, and a MUX unit. 27 and an upstream burst transmission control unit 28.

  The optical / electrical converter 21 converts the input optical signal into an electrical signal, and converts the optical signal into an optical signal when the electrical signal is input. The FEC encoding unit 22 performs FEC encoding on the input information and outputs it. The communication permission information termination unit 23 acquires the communication permission information transmitted from the OLT 1. The upstream frame buffer unit 25 holds an upstream data frame to be transmitted to the OLT 1. The communication request information generation unit 26 generates communication request information for requesting the OLT 1 to allocate an uplink data transmission band. The MUX unit 27 multiplexes and outputs a plurality of information input from different paths. The upstream burst transmission control unit 28 performs control for burst transmission of upstream data using the band allocated from the OLT 1.

  Next, the operation when the ONU 2 transmits data to the OLT 1 will be described with reference to FIG. First, ONU2 and OLT1 operate | move as a GE-PON system according to the prescription | regulation of IEEE802.3ah, and start communication.

  In the GE-PON system, as shown in FIG. 4, the OLT 1 transmits communication permission information to each ONU 2, and each ONU 2 transmits communication data according to the received communication permission information. This communication permission information includes information related to transmission timing (transmission permission time) and used bandwidth. By using these information, the OLT 1 controls each ONU 2 to realize uplink time division multiplex burst communication. Yes. Further, when the ONU 2 wants to transmit data, the ONU 2 transmits communication request information including information regarding the data amount to the OLT 1. The OLT 1 determines a bandwidth to be allocated to each ONU 2 based on the communication request information received from each ONU 2.

  After the communication of the GE-PON system is established, the FEC redundancy is adjusted between the FEC control information termination unit 15 of the OLT 1 and the FEC control information termination unit 24 of the ONU 2. Specifically, the FEC control information termination unit 15 and the FEC control information termination unit 24 exchange information necessary for controlling the FEC redundancy, and an appropriate FEC redundancy corresponding to the connection distance is set for each ONU 2. (The FEC redundancy of the FEC parity to be added to the data is selected and determined). The FEC control information termination unit 15 notifies the FEC information management table holding unit 19 and the FEC encoding unit 16 of the FEC redundancy selection result, and the FEC control information termination unit 24 notifies the FEC encoding unit 22 of the selection result. Notice. As a result, the OLT 1 and the ONU 2 complete the adjustment of the FEC redundancy, and transmit / receive data by adding the FEC parity of the selected FEC redundancy. Note that the connection distance between the OLT 1 and the ONU 2 can be calculated, for example, by measuring RTT (Round Trip Time) when the OLT 1 and the ONU 2 establish communication and using the measurement result.

  In the ONU 2, when a user data frame is input to the upstream frame buffer unit 25, frame storage information indicating the data amount (communication data amount) is output from the upstream frame buffer unit 25 to the communication request information generation unit 26, and a communication request The information generation unit 26 generates communication request information including frame storage information.

  The generated communication request information includes the user data frame output from the upstream frame buffer unit 26 and the FEC control information output from the FEC control information termination unit in the MUX unit 27 that has received an instruction from the upstream burst transmission control unit 28. The signals are multiplexed and transmitted to the FEC encoding unit 22 via the upstream burst transmission control unit 28. The FEC control information is information used when the OLT and the ONU adjust FEC redundancy.

  The FEC encoding unit 22 performs FEC encoding on the information received from the MUX unit 27, and the FEC encoded information is converted from an electrical signal to an optical signal by the optical / electrical conversion unit 21, and then transmitted to the OLT 1. In the transmission control by the uplink burst transmission control unit 28 at this time, the content of the communication permission information notified from the OLT 1 one cycle before follows.

  In the OLT 1, the optical signal received from the ONU 2 is converted into an electrical signal by the optical / electrical conversion unit 17, and the converted signal is decoded by the FEC encoding unit 16. The communication request information termination unit 18 extracts communication request information included in the decoded received signal and outputs the communication request information to the band allocation control unit 11. The bandwidth allocation control unit 11 aggregates communication request information acquired from a plurality of ONUs 2 as shown in FIG.

  Furthermore, when each ONU 2 is operated with the FEC redundancy shown in FIG. 5 for example, the bandwidth allocation control unit 11 determines each of the subscriber side communication devices determined according to the FEC redundancy that each ONU 2 operates. Is proportionally distributed to each ONU 2 (ONU 2-1, 2-2, 2-3) at a ratio of a: b: c according to the weighting index (a, b, c) for assigning the bandwidth fairly to . Then, the determined bandwidth allocation information for each ONU 2 is notified to the communication permission information generating unit 12, and the communication permission information generating unit 12 generates communication permission information for each ONU 2. The generated communication permission information for each ONU 2 is multiplexed with the downlink frame output from the downlink frame buffer unit 14 and the FEC control information acquired from the FEC control information termination unit 15 in the MUX unit 13.

  The FEC encoding unit 16 performs FEC encoding on the information multiplexed by the MUX unit 13, and the FEC encoded information is converted from an electrical signal to an optical signal by the optical / electrical conversion unit 17 and then transmitted to each ONU 2. The

  In each ONU 2, the optical / electrical converter 21 converts the optical signal received from the OLT 1 into an electrical signal, and the FEC encoder 22 performs FEC decoding on the output signal from the optical / electrical converter 21. Then, the communication permission information termination unit 23 extracts the communication permission information from the decoded signal and outputs it to the uplink burst transmission control unit 28.

  The uplink burst transmission control unit 28 controls the uplink frame buffer 25, the communication request information generation unit 26, and the FEC control information termination unit 24 according to the acquired communication permission information, and transmits the information received from the MUX unit 27. Details of the transmission operation are as described above.

  Thus, in this embodiment, the OLT is based on the transmission data amount indicated by the communication request information acquired from each ONU and the weighting index determined according to the FEC redundancy operated by each ONU. The upstream band is distributed to each ONU. As a result, the OLT can fairly allocate the bandwidth to each subordinate ONU. As a result, each ONU can perform uplink communication fairly without depending on the operating FEC redundancy.

Embodiment 2. FIG.
Next, the second embodiment will be described. The configuration of the communication system, OLT, and ONU of the present embodiment is the same as that of the above-described first embodiment (see FIGS. 1 to 3). The ONU operation is the same as the ONU 2 of the first embodiment. On the other hand, the operation of the OLT is different from the first embodiment only in the method for determining the bandwidth allocated to each ONU. Therefore, in this embodiment, an operation in which the OLT allocates a bandwidth to each ONU will be described.

  As shown in FIG. 6, the burst communication control overhead transmitted from the ONU has a burst communication control overhead added to the head and the tail of each ONU as shown in FIG. It has become. Therefore, in the present embodiment, bandwidth allocation is performed for ONUs with high FEC redundancy collectively, and bandwidth allocation is performed so as to reduce burst communication control overhead.

  For example, when a plurality of ONUs wish to transmit uplink data, normally, each ONU is permitted to transmit in a predetermined burst unit (bandwidth is allocated), and each ONU transmits uplink data in a period indicated by the burst unit. Send burst. On the other hand, in the present embodiment, for an ONU that requires multiple burst transmissions and that transmits FEC parity with an FEC redundancy equal to or higher than a predetermined threshold value to upstream data. In this case, a plurality of burst units are combined and transmission is permitted.

  By performing such control, an ONU having a large FEC redundancy can continuously transmit data over a plurality of burst units as shown in FIG. 6, and the bandwidth allocation is equivalent to the burst communication control overhead. Is advantageous. As a result, each ONU connected under the same OLT can perform uplink communication fairly without depending on the operating FEC redundancy.

Embodiment 3 FIG.
Next, Embodiment 3 will be described. The configuration of the communication system, OLT, and ONU of the present embodiment is the same as that of the first embodiment described above. A different part from OLT and ONU shown in Embodiment 1 is demonstrated below.

  Compared with the ONU operation according to the first embodiment, the ONU operation according to the present embodiment includes the FEC redundancy for each stored frame shown in FIG. 7 in addition to the frame storage information from the upstream frame buffer unit 25. The difference is that the communication request information generating unit 26 generates communication request information including the data length of the parity part. This FEC redundant parity is the parity of the communication data portion. That is, the data amount indicated by the communication request information generated by the ONU of the present embodiment (hereinafter referred to as transmission request data amount) indicates the total data amount of the communication data amount and the redundant parity data amount. Thereby, it is possible to request a band including a parity part other than the data area that can be used by the user. The parity length N is expressed as “N = L / 239 (in the case of L% 239 = 0), N = L / 239 + 1 (in the case of L% 239 = 1), where L is the data length of the communication data. Become.

  Further, the difference between the operation of the OLT of the present embodiment and the operation of the OLT of the first embodiment is that, for example, when each ONU operates with the FEC redundancy shown in FIG. 5, the OLT of the present embodiment is Based on the weighting index (a, b, c) corresponding to the FEC redundancy, the bandwidth is proportionally distributed to each ONU at a ratio of (1 / a) :( 1 / b) :( 1 / c). is there. For example, if the weighting index increases as the FEC redundancy increases, the ratio of the FEC redundancy parity to the allocated bandwidth increases as the weighting index increases. That is, if the bandwidth is allocated in proportion to the weighting index, the fairness of the used bandwidth cannot be maintained. Therefore, in the present embodiment, band control is performed so as to be proportional to the reciprocal of the weighting index.

  Instead of proportionally distributing the reciprocal of the weighting index corresponding to each ONU, a band may be given to ONUs having a large FEC redundancy as in the second embodiment.

  In addition, since it is known in advance that the communication request information transmitted from each ONU indicates the total data amount of the communication data amount and the redundant parity data amount, the FEC redundancy is determined in consideration of this. A weighting index may be determined. That is, a value corresponding to the above (1 / a), (1 / b), (1 / c), etc. may be determined in advance as a weighting index. In this way, the bandwidth allocation control performed by the OLT of the present embodiment and the bandwidth allocation control performed by the OLT of the first embodiment can be made identical.

  By performing such control, the upstream bandwidth can be distributed according to the communication request information from each ONU and the weighting index corresponding to the FEC redundancy operated by each ONU. Therefore, each ONU connected under the OLT Can perform uplink communication fairly without depending on the FEC redundancy being operated.

  In addition, as described above, after the communication is established, the FEC control information termination unit 15 of the OLT 1 and the FEC control information termination unit 24 of the ONU 2 execute the process of adjusting the FEC redundancy. The above processing may be executed. In this case, since the ONU 2 does not need to generate communication request information including the data length of the FEC redundant parity portion, the present embodiment can be realized only by changing the OLT 1.

  Thus, in this embodiment, the OLT is based on the transmission data amount indicated by the communication request information acquired from each ONU and the weighting index determined according to the FEC redundancy operated by each ONU. The upstream band is distributed to each ONU. Also, each ONU sums the data amount of data to be actually transmitted and the data amount of FEC redundant parity added to this data, and uses the total data amount obtained as a result to transmit the communication request information. It was decided to generate and send. Thereby, each ONU connected under the OLT can perform uplink communication more evenly as compared with the case of the first embodiment.

Embodiment 4 FIG.
Next, the fourth embodiment will be described. The configuration of the communication system and OLT of the present embodiment is the same as that of the first embodiment described above. FIG. 8 is a diagram illustrating a configuration example of the ONU 2a according to the fourth embodiment. The ONU 2a adds an input frame counter 29, an output frame counter 12, and a frame number measuring unit 31 to the ONU 2 (see FIG. 3) of the first embodiment, and generates a communication request instead of the communication request information generating unit 26. The structure provided with the part 26a is taken. Since other parts are the same as those in the first embodiment, the same reference numerals are given and description thereof is omitted.

  Next, the operation of the ONU 2a of the present embodiment will be described. Here, only parts different from the ONU 2 of the first embodiment will be described. The input frame counter 29 counts the number of frames input to the upstream frame buffer unit 25, and the output frame counter 12 counts the number of frames output from the upstream burst transmission control unit 28. The frame number measuring unit 31 monitors the input frame counter 29 and the output frame counter 30 and measures the number of frames stored in the upstream frame buffer 25. The measurement result is output to the communication request information generation unit 26a. Then, the communication request information generation unit 26a inserts the number of frames notified from the frame number measurement unit 31 when generating the communication request information into the frame number information area newly defined in the communication request information, and transmits the communication request information. Is generated.

  Differences between the operation of the OLT according to the present embodiment and the operation of the OLT according to the first embodiment will be described below. The OLT of this embodiment allocates a bandwidth to each ONU using a method different from that of the OLT of the first embodiment. As a specific example, when each ONU operates with the FEC redundancy shown in FIG. 9, the OLT according to the present embodiment uses the acquired information from each ONU and the FEC redundancy used with each ONU. In other words, the transmission request data amount declaration value (x, y, z) and the transmission request frame number declaration value (X, Y, Z) in the communication request information from the ONU, and the FEC redundancy Based on the weighting index (a, b, c), the bandwidth is proportionally distributed to each ONU at a ratio of (ax / X) :( by / Y) :( cz / Z).

  As shown in FIG. 7, in the frame format stipulated in IEEE 802.3ah, the redundant parity portion increases depending on the frame length, and the larger the redundant parity portion, the smaller the band that can be used by the user. Therefore, the OLT (bandwidth allocation control unit 11) of this embodiment calculates a pseudo frame length based on the transmission request data amount declaration value in the communication request information from the ONU and the transmission request frame number declaration value in the communication request information. However, the bandwidth allocation is also performed by weighting the value.

  As described above, in this embodiment, the OLT includes the transmission data amount indicated by the communication request information acquired from each ONU, and the number of frames stored in the upstream frame buffer unit (data frames desired to be transmitted). The upstream bandwidth is distributed to each ONU based on the weighting index determined according to the FEC redundancy that each ONU operates. Thereby, each ONU connected under the OLT can perform uplink communication fairly without depending on the FEC redundancy being operated.

Embodiment 5 FIG.
Next, the fifth embodiment will be described. The configuration of the communication system, OLT, and ONU of the present embodiment is the same as that of the fourth embodiment described above.

  The ONU according to the present embodiment determines the transmission request data amount declaration value including the FEC redundant parity portion in addition to the frame storage information from the upstream frame buffer unit 25 and transmits the communication request information to the OLT. The operation for determining the transmission data amount declaration value including this FEC redundant parity portion is the same as that of the ONU of the third embodiment. That is, the ONU of the present embodiment corresponds to a combination of the ONU of the third embodiment and the ONU of the fourth embodiment.

  Differences between the operation of the OLT according to the present embodiment and the operation of the OLT according to the fourth embodiment will be described below. The OLT of this embodiment allocates a bandwidth to each ONU using a method different from that of the OLT of the fourth embodiment. As a specific example, when each ONU operates with the FEC redundancy shown in FIG. 9, the OLT of this embodiment is based on the acquired information from each ONU and the FEC redundancy, that is, from the ONU. The transmission request data amount declaration value (x, y, z) and the transmission request frame number declaration value (X, Y, Z) in the communication request information, and the weighting index (FEC redundancy corresponding to the FEC redundancy operated in each ONU ( a, b, c), the bandwidth is proportionally distributed to each ONU at a ratio of (x / aX) :( y / bY) :( z / cZ). Other parts are the same as those in the fourth embodiment.

  As described above, in this embodiment, the OLT includes the transmission data amount indicated by the communication request information acquired from each ONU, and the number of frames stored in the upstream frame buffer unit (data frames desired to be transmitted). The upstream bandwidth is distributed to each ONU based on the weighting index determined according to the FEC redundancy that each ONU operates. Also, each ONU sums the data amount of data to be actually transmitted and the data amount of FEC redundant parity added to this data, and uses the total data amount obtained as a result to transmit the communication request information. It was decided to generate and send. Thereby, each ONU connected under the OLT can perform uplink communication fairly without depending on the FEC redundancy being operated.

Embodiment 6 FIG.
Next, the sixth embodiment will be described. The configuration of the communication system and ONU of the present embodiment is the same as that of the first embodiment described above.

  FIG. 10 is a diagram illustrating a configuration example of the OLT according to the sixth embodiment. The OLT 1b shown in FIG. 10 has a configuration including a band allocation control 11b and an FEC information management table holding unit 19b instead of the band allocation control 11 and the FEC information management table holding unit 19 of the first embodiment. The management table holding unit 19b has a function of communicating with the billing server 20. Since other parts are the same as those in the first embodiment, the same reference numerals are given and description thereof is omitted.

  In the bandwidth allocation control 11b of the OLT 1b, compared with the bandwidth allocation control unit 11 of the first embodiment, bandwidth control is performed based on the weighting index obtained from each ONU and according to the FEC redundancy that is operated in the ONU. There is no difference. In this case, unfairness occurs in the used bandwidth due to the FEC redundancy of the ONU.

  For this reason, in this embodiment, this unfairness is eliminated by accounting. That is, the FEC information management table holding unit 19 notifies the billing server 20 of the FEC redundancy corresponding to the ONU that performs communication, so that discounts are given to ONUs (subscribers) that have high FEC redundancy and are disadvantageous in terms of bandwidth. Do. The timing for notifying the FEC redundancy is, for example, when communication with the ONU is started. The accounting server 20 performs accounting processing according to the notified FEC redundancy. Specifically, a fee is charged so that the communication fee is lower for a communication with a higher FEC redundancy. Thereby, the above-mentioned unfairness can be solved in terms of fee.

  In each of the above-described embodiments, the case where the present invention is applied to the GE-PON system is shown as an example. However, needless to say, the application system is not limited to this, and the multi-branch connection optical communication system is used. Widely adaptable.

  As described above, the communication apparatus according to the present invention is useful for an optical communication system, and in particular, an FEC redundancy error correction code corresponding to the connection distance between the subscriber-side communication apparatus and the station-side communication apparatus is assigned. Therefore, it is suitable for a communication apparatus on the station side of an optical communication system that performs data transmission.

It is a figure which shows the structural example of Embodiment 1 of the communication system containing the communication apparatus concerning this invention. 2 is a diagram illustrating a configuration example of an intra-station apparatus (OLT) according to the first embodiment. FIG. It is a figure which shows the structural example of the subscriber apparatus (ONU) of Embodiment 1. FIG. It is a figure which shows the uplink data communication operation | movement outline | summary in the communication system concerning this invention. It is a figure which shows an example of the redundancy referred at the time of band allocation operation | movement. It is a figure which shows an example of the data format used by uplink burst communication. It is a figure which shows the FEC format prescribed | regulated by IEEE802.3ah. FIG. 10 is a diagram illustrating a configuration example of an ONU according to a fourth embodiment. It is a figure which shows an example of the redundancy referred at the time of band allocation operation | movement. FIG. 10 is a diagram illustrating a configuration example of an OLT according to a sixth embodiment.

Explanation of symbols

1, 1b Intra-station equipment (OLT)
2, 2a, 2-1, 2-2, 2-3 subscriber unit (ONU)
3 Optical coupler 4 Optical fiber 11, 11 b Band allocation control unit 12 Communication permission information generation unit 13, 27 MUX unit 14 Downstream frame buffer unit 15 FEC control information termination unit 16, 22 FEC encoding unit 17, 21 Optical / electrical conversion unit 18 Communication request information termination unit 19, 19b FEC information management table holding unit 20 Billing server 23 Communication permission information termination unit 24 FEC control information termination unit 25 Up frame buffer unit 26, 26a Transmission request information generation unit 28 Up burst transmission control unit 29 Input Frame counter 30 Output frame counter 31 Frame number measurement unit

Claims (13)

A PON system is configured together with a plurality of subscriber side communication devices for time-division multiplexing transmission of uplink data, and data with an error correction code with redundancy determined individually for each subscriber side communication device is transmitted to the subscriber side. A station-side communication device that transmits and receives data to and from a communication device,
From each of the subscriber side communication devices, communication request information acquisition means for acquiring information on the amount of uplink data desired to be transmitted,
Band allocation control means for determining a bandwidth for uplink data transmission to be allocated to each subscriber side communication device based on the data amount information of the uplink data acquired by the communication request information acquisition means and the redundancy,
A communication apparatus comprising:   The band allocation control means includes a plurality of burst units indicating one burst transmission time for a subscriber-side communication apparatus that transmits uplink data to which an error correction code having a redundancy equal to or greater than a predetermined threshold is transmitted. The communication apparatus according to claim 1, wherein transmission is permitted over a grouped period. Based on the redundancy, individually corresponding to each of the subscriber side communication devices, a weighting index for assigning a bandwidth fairly to each of the subscriber side communication devices is determined in advance,
The communication apparatus according to claim 1, wherein the band allocation control unit determines the band based on data amount information of the uplink data and the weighting index.   4. The communication apparatus according to claim 3, wherein the band allocation control unit allocates a larger band to a subscriber side communication apparatus having a larger weighting index. The communication request information acquisition means further acquires information on the number of uplink data frames desired to be transmitted,
2. The communication apparatus according to claim 1, wherein the bandwidth allocation control unit determines the bandwidth based on the uplink data frame number information in addition to the data amount information and the redundancy of the uplink data. . A PON system is configured together with a plurality of subscriber side communication devices for time-division multiplexing transmission of uplink data, and data with an error correction code with redundancy determined individually for each subscriber side communication device is transmitted to the subscriber side. A station-side communication device that transmits and receives data to and from a communication device,
From each of the subscriber side communication devices, communication request information acquisition means for acquiring information on the total data amount of the data amount of the uplink data desired to be transmitted and the data amount of the error correction code attached to the uplink data;
Band allocation control means for determining a bandwidth for uplink data transmission to be allocated to each subscriber side communication device based on the total data amount information acquired by the communication request information acquisition means and the redundancy;
A communication apparatus comprising:   The band allocation control means includes a plurality of burst units indicating one burst transmission time for a subscriber-side communication apparatus that transmits uplink data to which an error correction code having a redundancy equal to or greater than a predetermined threshold is transmitted. The communication apparatus according to claim 6, wherein transmission is permitted over a grouped period. Based on the redundancy, individually corresponding to each of the subscriber side communication devices, a weighting index for assigning a bandwidth fairly to each of the subscriber side communication devices is determined in advance,
The communication apparatus according to claim 6, wherein the band allocation control unit determines the band based on data amount information of the uplink data and the weighting index.   9. The communication apparatus according to claim 8, wherein the band allocation control unit allocates a larger band to a subscriber side communication apparatus having a larger weighting index. The communication request information acquisition means further acquires information on the number of uplink data frames desired to be transmitted,
The communication apparatus according to claim 6, wherein the band allocation control unit determines the band based on the uplink data frame number information in addition to the total data amount information and the redundancy. A subscriber-side communication device that constitutes a PON system together with the station-side communication device according to any one of claims 1 to 5 and transmits uplink data to which an error correction code is added to the station-side communication device. And
Information notification means for notifying the station side communication device of information on the amount of uplink data desired to be transmitted and information on the number of uplink data frames desired to be transmitted;
Information acquisition means for acquiring information of a band determined by the station side communication device based on the information notified by the information notification means;
A communication apparatus comprising: A subscriber-side communication device that constitutes a PON system together with the station-side communication device according to any one of claims 6 to 10 and transmits uplink data to which an error correction code is added to the station-side communication device. And
Information on the total data amount of the amount of uplink data desired to be transmitted and the amount of error correction code added to the uplink data, and information on the number of uplink data frames desired to be transmitted are notified to the station side communication device Information notification means to
Information acquisition means for acquiring information of a band determined by the station side communication device based on the information notified by the information notification means;
A communication apparatus comprising: A plurality of subscriber-side communication devices and a station-side communication device that transmits and receives data to which error-correction codes with redundancy determined individually for each subscriber-side communication device are added to and received from the subscriber-side communication device And a billing server, and an optical communication system comprising:
The station side communication device is:
When communicating with the subscriber side communication device, notify the billing server of the redundancy of the error correction code given to the data transmitted and received between the subscriber side communication device,
The billing server
An optical communication system characterized by executing a billing process according to the redundancy notified from the station side communication device.

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