JP2021027571A - Pon system, station-side termination device, communication apparatus, and computer program - Google Patents

Abstract

To appropriately execute a control communication for a plurality of station-side termination devices even without using apparatus-specific identification information.SOLUTION: A PON system comprises: a plurality of station-side termination devices configured to terminate corresponding PON lines; a communication apparatus which performs a control communication using a control frame with the plurality of station-side termination devices; and a line concentrator to which the plurality of station-side termination devices and the communication apparatus are connected. In the PON system, the control frame to be communicated between the line concentrator and the plurality of station-side termination devices is a first frame as follows, and the control frame to be communication between the communication apparatus and the line concentrator is a second frame as follows. Namely, the first frame is a communication frame including first tag information which is common to the plurality of station-side termination devices, and the second frame is a communication frame including second tag information which is different for each physical port of the line concentrator to which the plurality of station-side termination devices are connected.SELECTED DRAWING: Figure 4

Description

The present invention relates to PON systems, station-side termination devices, communication devices, and computer programs.

In recent years, in order to meet the demand for lower cost or diversification of communication equipment, it has been studied to make the communication function of the communication equipment into a component by software.
Specifically, instead of customizing the hardware parts of communication equipment, the minimum communication functions are left in the hardware parts, and other communications such as functions for specific operators and functions that need to be updated frequently. Virtualization is being considered for the application components of the device to execute.

In Patent Documents 1 and 2, as a part of the above virtualization, the DBA (Dynamic Bandwidth Allocation) function of the OLT (Optical Line Terminal) constituting the PON (Passive Optical Network) system is operated on the OS (Operating System). The communication device to be executed by the application component to be executed is described.
Non-Patent Documents 1 and 2 specify requirements for API (Application Programming Interface) function or performance when a DBA having strict time constraints is used as an application component.

Japanese Unexamined Patent Publication No. 2018-074467 International Publication No. 2019/017427

BBF (Broadband Forum) TR-402 Functional Model for PON Abstraction Interface, Issue: 1.0, Issue Date: October 2018 BBF (Broadband Forum) TR-403 PON Abstraction Interface Specifications, Issue: 1.0, Issue Date: October 2018

When a part of the PON function is transferred to an application component of another communication device as in Patent Documents 1 and 2, the more functions to be transferred, the more general-purpose and miniaturized the OLT can be compared with the conventional product.
Therefore, for example, by directly connecting a plurality of OLTs to the physical ports of the concentrator device, it is possible to configure an OLT collective type station-side termination device in which the plurality of OLTs are integrated in the housing of the concentrator device.

In this way, in the connection form in which the OLT is connected to a plurality of physical ports of the concentrator, if the OLT is identified by the identification information such as the MAC (Media Access Control) address, the communication device for the OLT setting is the physical OLT. Even if it is connected to the port, the destination and source of the setting frame can be specified.
However, considering the progress of generalization of OLT, it is desirable that control communication for OLT connected to an arbitrary physical port can be appropriately executed without using device-specific identification information such as MAC address. Is done.

In view of the conventional problems, an object of the present invention is to enable appropriate control communication for a plurality of station-side termination devices without using device-specific identification information.

(1) The system according to one aspect of the present invention includes a plurality of station-side termination devices for terminating corresponding PON lines, a communication device for performing control communication using the plurality of station-side termination devices and a control frame, and the above. A PON system including a concentrator device to which a plurality of station-side terminal devices and the communication device are connected, and the control frame communicated between the concentrator device and the plurality of station-side terminal devices is a control frame. The first frame below, and the control frame communicated between the communication device and the line concentrator, is the second frame below.
First frame: Communication frame containing the first tag information common to a plurality of station-side terminal devices Second frame: Communication including a second tag information different for each physical port of the concentrator to which a plurality of station-side terminal devices are connected. flame

(6) The device according to one aspect of the present invention includes an upper transmission / reception unit connected to the concentrator device, a lower transmission / reception unit connected to the PON line, and a communication device and a control frame connected to the concentrator device. A station-side termination device including a frame processing unit that performs control communication using the line-concentrator, and at least one other station-side termination device other than the own device can be connected to the line-collecting device. The control frame communicated with the plurality of station-side termination devices including the own device includes a communication frame including the first tag information common to the plurality of station-side termination devices.

(7) The device according to another aspect of the present invention includes a communication unit connected to the concentrator device, a control unit that performs control communication using a plurality of station-side termination devices connected to the concentrator device, and a control frame. The control frame for communication between the concentrator and the plurality of station-side termination devices is different for each physical port of the concentrator to which the plurality of station-side termination devices are connected. It consists of a communication frame containing the second tag information.

(8) The computer program according to one aspect of the present invention is a computer program that functions a computer as a communication device that performs control communication using a control frame with a plurality of station-side termination devices connected to a line concentrator. A step of storing different tag information for each physical port of the concentrator to which the plurality of station-side termination devices are connected, and which station side of the plurality of station-side termination devices is based on the stored tag information. Includes a step of identifying the control frame for the termination device.

The present invention can be realized not only as a system and an apparatus having the above-mentioned characteristic configuration, but also as a program for causing a computer to execute such a characteristic configuration.
Further, the present invention can be realized as a semiconductor integrated circuit that realizes a part or all of a system and an apparatus.

According to the present invention, control communication with a plurality of station-side termination devices can be appropriately executed without using device-specific identification information.

It is a block diagram which shows an example of the whole structure of an optical communication system. It is a block diagram which shows an example of the internal structure of a general-purpose server. It is a schematic diagram which shows an example of the connection form (topology) of the optical communication system which has a plurality of small OLTs. It is explanatory drawing which shows an example of the setting procedure of the transfer rule for a line concentrator. This is a table summarizing the transfer rules of communication frames applied to the concentrator. It is explanatory drawing which shows an example of the transfer path of the communication frame by a concentrator. It is explanatory drawing which shows another example of the transfer path of the communication frame by a concentrator. It is a block diagram which shows an example of the hardware configuration of OLT.

<Outline of Embodiment of the present invention>
Hereinafter, the outlines of the embodiments of the present invention will be described in a list.

(1) The PON system of the present embodiment includes a plurality of station-side terminating devices for terminating corresponding PON lines, a communication device for performing control communication using the plurality of station-side terminating devices and a control frame, and the plurality of PON systems. A PON system including a line concentrator for connecting a station-side terminal device and the communication device, and the control frame for communication between the line concentrator and the plurality of station-side terminal devices is described below. The control frame which is the first frame and is communicated between the communication device and the line concentrator is the following second frame.
First frame: Communication frame containing the first tag information common to a plurality of station-side terminal devices Second frame: Communication including a second tag information different for each physical port of the concentrator to which a plurality of station-side terminal devices are connected. flame

According to the PON system of the present embodiment, the control frame communicated between the concentrator and the plurality of station-side termination devices is composed of the above-mentioned first frame, and the control is communicated between the communication device and the concentrator. Since the frame is composed of the above-mentioned second frame, it is possible to logically associate a communication device having a one-to-many correspondence with a plurality of station-side termination devices in a one-to-one relationship.
Therefore, the communication device can uniquely identify a plurality of station-side termination devices, and control communication for the plurality of station-side termination devices can be appropriately executed without using identification information unique to the station-side termination device. Will be.

(2) In the PON system of the present embodiment, when the concentrator device has a user port which is a physical port to which a higher-level device is connected, communication is performed between the concentrator device and the plurality of station-side termination devices. The user frame and the user frame communicated in the user port are preferably the following third frames.
Third frame: A communication frame containing the third Doug information associated with the identification information of the subscriber side termination device of the PON line.

According to the PON system of the present embodiment, the user frame communicated on the upper side and the lower side of the line concentrator device is composed of the above-mentioned third frame, so that the subscriber side terminal device that is the source and destination of the user frame is concentrated. It becomes possible to identify from the upper side of the device.

(3) In the PON system of the present embodiment, when the concentrator device transfers the control frame between physical ports, the tag information of the communication frame before and after the transfer is associated with each other on a one-to-many basis, and the user frame is associated with the physical port. When transferring between, it is preferable to associate the tag information of the communication frames before and after the transfer on a one-to-one basis.
The reason is that the second tag information of the control frame is common information, and the first tag information of the control frame is a plurality of information different for each physical port. Further, the third tag information of the user frame is a plurality of information associated with the identification information of the subscriber side termination device on the upper side and the lower side of the concentrator, respectively.

(4) In the PON system of the present embodiment, when the communication device has software components for realizing the setting related to the PON communication, the setting information necessary for the setting is transmitted to the control frame. It is preferable that the setting frame of is included.
In this case, the communication device can set a plurality of station-side termination devices connected to the line concentrator by operating the software component using the setting information obtained in the above setting frame.

(5) In the PON system of the present embodiment, when the communication device has software components for realizing a part of the PON function, the control frame is required for the part of the function. It is preferable to include a functional frame for transmitting functional information.
In this case, the communication device performs some functions of the PON function for a plurality of station-side termination devices connected to the concentrator by executing software components using the functional information obtained in the above functional frame. It will be possible to substitute.

(6) The station-side termination device of the present embodiment relates to a station-side termination device that is a component (sub-combination) of the PON system described in (1) to (5) above.
Therefore, the station-side termination device of the present embodiment has the same effect as the PON system of (1) to (5) described above.

(7) The communication device of the present embodiment relates to a communication device that is a component (sub-combination) of the PON system described in (1) to (5) above.
Therefore, the PON system of the present embodiment has the same effect as the PON system of (1) to (5) described above.

(8) The computer program of the present embodiment is a computer program that functions a computer as a communication device that performs control communication using a control frame with a plurality of station-side termination devices connected to the line concentrator, and is the plurality of computer programs. A step of storing different tag information for each physical port of the concentrator to which the station-side termination device is connected, and which station-side termination device of the plurality of station-side termination devices is based on the stored tag information. A step of identifying the control frame for the purpose.

According to the computer program of the present embodiment, since the step of identifying which station side termination device of the plurality of station side termination devices is the control frame based on the stored tag information is included, there are a plurality of communication devices. The station-side termination device can be uniquely identified.
Therefore, control communication for a plurality of station-side termination devices can be appropriately executed without using identification information unique to the station-side termination device.

<Details of Embodiments of the present invention>
Hereinafter, the details of the embodiment of the present invention will be described with reference to the drawings. In addition, at least a part of the embodiments described below may be arbitrarily combined.

[Overall configuration of optical communication system]
FIG. 1 is a schematic view showing an example of the overall configuration of an optical communication system.
As shown in FIG. 1, the optical communication system of the present embodiment is a PON system including a station-side termination device 1, a subscriber-side termination device 2, a line concentrator 3, a general-purpose server 4, a host device 5, and the like.

In the present embodiment, the PON is a PON (for example, GE-PON or 10GE-PON, etc.) that conforms to an IEEE-based communication standard.
However, the PON may be a PON (for example, G-PON, XG-PON, XGS-PON, NG-PON2, etc.) that complies with the ITU-T communication standard.

The station-side termination device 1 is composed of an optical network unit (OLT) on the upper side of the PON line. The subscriber side termination device 2 includes an optical network unit (ONU) on the lower side of the PON line.
The station-side termination device 1 is installed in, for example, a telecommunications carrier's station building together with the line concentrator 3, the general-purpose server 4, and the host device 5. The subscriber-side termination device 2 is installed in the home of a subscriber of the communication service. The general-purpose server 4 may be communicatively connected to the OLT 1 by an optical line or the like and may be installed in a remote location outside the station building.

The PON line is a tree-structured optical line in which an optical fiber is branched by an optical coupler. The station side terminating device 1 is connected to the trunk fiber of the PON line, and the subscriber side terminating device 2 is connected to the branch line fiber of the PON line.
Hereinafter, the station-side terminating device 1 of the PON line will be referred to as “OLT1”, and the PON line subscriber-side terminating device 2 will be referred to as “ONU2”.

The line concentrator 3 includes, for example, an L2 switch. The concentrator 3 determines a physical port for transmitting a received communication frame according to a destination, a source, a type, and the like of the communication frame.
For example, the concentrator 3 communicates the physical port of the OLT 1 with the physical port of the host device 5 for the communication frame of the main signal system such as the user frame. The concentrator 3 communicates the physical port of the OLT 1 with the physical port of the general-purpose server 4 for the control frame.

The general-purpose server 4 comprises a personal computer (PC) equipped with an OS such as Linux (registered trademark). The general-purpose server 4 functions as a communication device for executing user management and service settings related to PON communication between OLT1 and ONU2 by communicating with OLT1 on a predetermined communication line (for example, a LAN cable).
The host device 5 is a communication device connected to a host network (not shown). The host device 5 includes, for example, an edge router.

In the optical communication system of the present embodiment, a part of the PON function executed by the hardware component of the conventional OLT is a software component executed by the CPU (Central Processing Unit) of the general-purpose server 4, so that the OLT function is executed. A part of the above has been migrated to the general-purpose server 4.
The more functions related to PON communication that are transferred to the general-purpose server 4, the more general-purpose and miniaturized the OLT1 can be compared with the conventional product. For example, the OLT 1 of the present embodiment is composed of an optical communication device downsized to an SFP (Small Form-factor Pluggable) module. Therefore, in the following, OLT1 will also be referred to as "small OLT1".

In FIG. 1, a case where the functions (software components) to be migrated to the general-purpose server 4 are DBA (Dynamic Bandwidth Allocation) and OAM (Operation Administration and Maintenance) is illustrated.
Since the DBA is a function of dynamically allocating the upstream band of the PON line, it influences the QoS (Quality of Service) of the PON communication. Therefore, if the DBA is migrated to the general-purpose server 4, the contents of the DBA such as QoS can be flexibly changed or added only by modifying or adding software parts related to the DBA.

When migrating the functions of DBA and OAM to the general-purpose server 4, the control frames transmitted and received between the OLT 1 and the general-purpose server 4 have a common information format in addition to the parameter setting information for user management and service setting. OAM message and DBA bandwidth information are included.
When there are two types of functions to be migrated to the general-purpose server 4, DBA and OAM, the other functions required for PON communication such as MPCP (Multi Point Control Protocol), encryption, and VLAN (Virtual LAN) are OLT1. It remains as a function executed by hardware components such as the frame processing unit 12 (see FIG. 3).

The function related to PON communication transferred to the general-purpose server 4 may be at least one function executed by the hardware component of the conventional OLT, and is not limited to DBA and OAM.
For example, the function related to PON communication that shifts to the general-purpose server 4 may include a power saving function that controls ONU2 to sleep, a registration and authentication function of ONU2, and the like.

[Hardware configuration of general-purpose server]
FIG. 2 is a block diagram showing an example of the internal configuration of the general-purpose server 4.
As shown in FIG. 2, the general-purpose server 4 of the present embodiment includes a housing 40, and a control unit 41, a storage unit 42, and a communication unit 43 housed in the housing 40. The operation unit 44 and the display unit 45 are connected to the housing 40 of the general-purpose server 4.

The control unit 41, the storage unit 42, and the communication unit 43 are mounted on the backplane inside the housing 40. The operation unit 44 and the display unit 45 are connected to predetermined connectors on the backplane, respectively. The control unit 41 controls the operation of each of the hardware units 42 to 45.
The control unit 41 includes an arithmetic processing unit including a CPU and a main memory including a RAM (Random Access Memory). The CPU of the control unit 41 reads the computer program (software) 46 installed in the storage unit 42 into the main memory, and performs various information processing according to the program 46.

The storage unit 42 includes a recording medium composed of at least one non-volatile memory of HDD (Hard Disk Drive) and SSD (Solid State Drive), and at least one of external or internal optical drives. It consists of an auxiliary storage device.
The communication unit 43 includes a communication card (for example, a LAN card) that performs Ethernet (registered trademark) communication with an external device. The communication unit 43 is connected to the line concentrator 3 by a predetermined communication cable such as a LAN cable.

The operation unit 44 includes an input device such as a keyboard and a pointing device. The operator of the telecommunications carrier issues a predetermined command (for example, a control command to the OLT setting unit 52, the switch control unit 53, etc.) to the control unit 41 of the general-purpose server 4 by inputting a command to the operation unit 44 or performing an operation input such as clicking. Can be sent.
The display unit 45 includes a display device such as a liquid crystal monitor or an organic EL panel. The display unit 45 can display a GUI (Graphical User Interface) screen or the like for receiving an operation input to the operation unit 44.

[Software configuration of general-purpose server]
As shown in FIG. 2, the computer program (software) 46 that the CPU of the control unit 41 reads from the storage unit 42 and executes the computer program (software) 46 includes a middleware unit 48 that operates on the OS 47, one or a plurality of application components 49, and internal components. The API 50 and the external API 51 are included. The computer program 46 also includes an OLT setting unit 52, a switch control unit 53, and external APIs 54 and 55. In this embodiment, "application" may be abbreviated as "application".

The computer program 46 can be distributed as a software product by storing it in a removable recording medium such as a USB memory in addition to the recording medium constituting the storage unit 42 of the general-purpose server 4.
The computer program 46 can also be distributed as a software product through a public communication network such as the Internet. When the computer program 46 is stored in the general-purpose server 4 via a USB memory or a network, it is not always necessary to provide an optical drive in the general-purpose server 4.

In the following, the situation in which the operability of the application component 49 depends on at least one difference between the type of communication standard (including version) and the manufacturing vendor to which the communication device such as OLT1 conforms is referred to as "device-dependent". That is.
On the contrary, the situation in which the operationability of the application component 49 does not depend on the type (including version) of the communication standard to which the communication device such as OLT1 conforms and the difference in the manufacturing vendor is called "device-independent".

The middleware unit 48 is software that absorbs differences in software and / or hardware lower than the application component 49 by providing the internal API 50 to the application component 49.
The application component 49 is a general-purpose software component that can be replaced by the internal API 50. A software component is software in which necessary functions are grouped in replaceable units.

In FIG. 2, the DBA application 49A, the power saving application 49B, and the OAM application 49C are exemplified as the application component 49.
The DBA application 49A is an application component for realizing a DBA function that dynamically allocates the upstream band of ONU2. The power saving application 49B is an application component for realizing a power saving function that controls ONU2 in sleep mode. The OAM application 49C is an application component for realizing the OAM function between OLT1 / ONU2.

The internal API 50 is a device-independent input / output interface. The application parts 49A to 49C are connected to the middleware unit 48 via the internal APIs 50A to 50C defined for each of the application parts 49A to 49C.
Therefore, the middleware unit 48 inputs / outputs predetermined information to the application parts 49A to 40C by the internal APIs 50A to 50C.

The external API 51 is a device-dependent input / output interface. The middleware unit 48 is connected to a hardware component of an external communication device (for example, FPGA of OLT1) via external APIs 51A to 51C defined for each of the application components 49A to 49C.
Therefore, the middleware unit 48 inputs / outputs predetermined information to the hardware components of the external communication device by the external APIs 51A to 51C.

The information format of the external API 51 is standardized for each of the application parts 49A to 49C. The external API 51 includes a control frame such as a “functional frame”.
The function frame is a control frame for transmitting functional information (transmission request amount and grant information in the case of DBA) required to execute a part of the PON function. Therefore, the external API 51A in the case of the DBA application 49A includes a "batch report" and a "batch gate". Hereinafter, the collective report and the collective gate are collectively referred to as "DBA frame".

The batch report is a control frame transmitted from the OLT 1 to the general-purpose server 4 in which the amount of transmission requests in the upward direction of each ONU 2 connected to the OLT 1 is stored.
The middleware unit 48 inputs the upward transmission request amount of each ONU2 described in the batch report received from the OLT1 by the communication unit 43 to the DBA application 49A via the internal API 50A. The DBA application 49A executes a predetermined DBA algorithm with the input transmission request amount of each ONU2 as a variable, and calculates the grant information (transmission start time and transmission time length) to be assigned to each ONU2 for each LLID (Logical Link ID). To do.

The batch gate is a control frame transmitted from the general-purpose server 4 to the OLT 1 in which the grant information of each ONU 2 connected to the OLT 1 is stored.
The DBA application 49A outputs the calculated grant information for each LLID assigned to each ONU2 to the middleware unit 48 via the internal API 50A. The middleware unit 48 generates a batch gate addressed to OLT1 including grant information for each input LLID, and causes the communication unit 43 to transmit the generated batch gate.

The OLT setting unit 52 is a management software component for realizing various settings related to PON communication, such as setting parameters for OLT 1 and acquiring registration information of ONU 2 accommodated in OLT 1.
The external API 54 is at least one device-dependent or device-independent input / output interface that connects the OLT setting unit 52 of the general-purpose server 4 and the hardware component of the OLT 1 (for example, the FPGA of the OLT 1).

As the OLT setting unit 52, for example, VOLTHA (Virtual OLT Hardware Abstraction) provided by ONF (Open Networking Foundation) or software conforming to a predetermined communication protocol such as Netconf / YANG can be adopted.
However, it is assumed that the OLT setting unit 52 of the present embodiment is software conforming to VOLTHA, which has many device-independent external APIs 54 and is highly versatile.

The external API 54 includes a control frame such as a “setting frame”.
The setting frame is a control frame for transmitting the setting information required for setting the PON. Since the OLT setting unit 52 of the present embodiment is software conforming to VOLTHA, the setting frame is also referred to as a "VOLTHA frame".
The setting information included in the VOLTHA frame includes, for example, the number of ONU2s accommodated, the registered ONU2 LLID value, the correspondence information between the LLID value and the value of the identifier (hereinafter referred to as "VID") written in the VLAN tag. And user information for each LLID and the like are included.

The switch control unit 53 is a software component for communicating with the concentrator device 3 according to a predetermined communication protocol and realizing setting of a transfer rule by the concentrator device 3.
The external API 55 is at least one device-dependent or device-independent input / output interface that connects the switch control unit 53 of the general-purpose server 4 and the concentrator device 3.

As the switch control unit 53, for example, software that conforms to a predetermined communication protocol such as OpenFlow (registered trademark) provided by ONF or Netconf / YANG can be adopted.
However, it is assumed that the switch control unit 53 of the present embodiment is software conforming to OpenFlow, which has many device-independent APIs and is highly versatile. Therefore, the switch control unit 53 functions as an OpenFlow controller, and the line concentrator 3 functions as an OpenFlow switch.

The switch control unit 53 sets a transfer rule for a communication frame applied to the concentrator 3 based on an operation input to the operation unit 44 by the operator of the communication carrier, and communicates via an external API (Southbound API) 55. The set transfer rule is transmitted to the line concentrator 3. The concentrator 3 determines the physical port for transmitting the received frame according to the transfer rule acquired from the switch control unit 53.
A specific example of the transfer rule of the line concentrator 3 (FIG. 5) will be described later.

[Problems and solutions when connecting multiple small OLTs to the concentrator]
FIG. 3 is a schematic diagram showing an example of a connection form (topology) of an optical communication system having a plurality of small OLT1s.
As shown in FIG. 3, the OpenFlow-compatible line concentrator 3 includes a plurality of physical ports Pi (i = 1, 2, ... n) and a plurality of physical ports Q1 to Q4.

The physical port Pi is a physical port for OLT1. The physical port Q1 is a physical port for the switch control unit 53 (for OpenFlow). The physical port Q2 is a physical port for the OLT setting unit 52 (for VOLTHA).
The physical port Q3 is a physical port for the middleware unit 48. The physical port Q4 is a physical port for the main signal. Here, it is assumed that the middleware unit 48 operates for the DBA application 49A, but other applications 49B and 49C may be used.

Since the OLT 1 of the present embodiment is composed of an SFP module, for example, as shown in FIG. 3, a plurality of small OLT 1s can be directly connected to the physical ports Pi (i = 1, 2, ... n) of the concentrator 3. ..
Therefore, it is possible to configure an OLT collective type station-side termination device in which a plurality of small OLTs 1 are integrated in the housing of the line concentrator 3. If the OLT1 is not a direct connection type or is large, each OLT1 may be connected to the physical port Pi with a LAN cable or the like.

When the OLT1 is connected to a plurality of physical ports Pi of the concentrator 3, if the OLT1 is identified by the device-specific identification information such as the MAC address, the OLT setting unit 52 can connect the OLT1 to any physical port Pi. , The destination and source of the setting frame can be specified.
However, considering the progress of generalization of the small OLT1, it is possible to appropriately execute control communication for setting the OLT1 connected to an arbitrary physical port Pi without using device-specific identification information. desired.

Therefore, in the present embodiment, the communication between the OLT setting unit 52 and the plurality of OLT 1s is logically associated with each other in a one-to-one relationship by using the predetermined tag information (VID value in the present embodiment) of the communication frame. Specifically, the VID value of the setting frame communicated between the OLT 1 and the concentrator 3 is standardized, and the VID value of the setting frame communicated between the OLT setting unit 52 and the concentrator 3 is connected to the OLT 1. By setting different values according to the port number of the physical port Pi, the OLT setting unit 52 and a plurality of OLT1s are logically associated with each other in a one-to-one relationship.
Therefore, control communication by setting frames for a plurality of OLT1s can be appropriately executed without using the identification information unique to the OLT1.

On the other hand, since the number of ONU2s installed is larger than that of the OLT1 and is easily changed, it is difficult to identify the user frame of the ONU2 by using the port number of the physical port Pi to which the OLT1 is connected. Therefore, it is necessary to determine the VID value as dynamically as possible.
Therefore, in the present embodiment, by assigning a VID value corresponding to the LLID value to the user frame, the ONU2 that is the source and destination of the user frame can be identified from the upper side of the concentrator. Hereinafter, a specific example of the procedure for setting the transfer rule for the concentrator 3 according to the above solution will be described.

[Procedure for setting forwarding rules]
FIG. 4 is an explanatory diagram showing an example of a procedure for setting a transfer rule for the concentrator device 3.
As shown in FIG. 4, the transfer rule setting procedure of the present embodiment includes the processing of the next steps S1 to S3 by the switch control unit 53 and the processing of the next steps T1 to T2 by the OLT setting unit 52. .. In the following, it is assumed that the three small OLTs 1X to 1Z are connected to the physical ports P1 to P3 of the concentrator 3. Further, the generic name of the drawing reference reference numerals "1X to 1Z" relating to OLT is "1".

Step S1: Transfer rule setting process related to VOLTHA Step S2: Transfer rule setting process related to DBA Step S3: Transfer rule setting process related to main signal (user frame) Step T1: Collection / notification of LLID value Step T2: ID correspondence information Reception / Transmission The contents of each step S1 to S5 and T1 to T2 will be described below.

(Step S1: Transfer rule setting process for VOLTHA)
Under the following preconditions S11 and S12, the switch control unit 53 executes the next transfer rule determination process S13 in response to an operation input to the operation unit 44.

S11) VID value between switch / OLT (prerequisite)
A communication frame having a common VID value = 4092 set as a reserved value in each OLT1 is defined as a VOLTHA frame. The VID value is recorded in, for example, the ROM of OLT1.
Therefore, the VID value of 4092 is an index for OLT1 to identify the VOLTHA frame uniformly regardless of the port number i of the physical port Pi. Note that "4092" is an example, and any value other than the reserved value can be adopted.

S12) VID value between VOLTHA / switch (prerequisite)
A communication frame having a VID value different for each port number i of the physical port Pi, which is recorded as a reserved value in the storage unit 42 of the general-purpose server 4, is referred to as a VOLTHA frame. For example, the communication frame of the next VID value is set as a VOLTHA frame.
VID value for port P1 (OLT1X) → 100
VID value for port P2 (OLT1Y) → 101
VID value for port P3 (OLT1Z) → 102

Therefore, the VID value of 100 is an index for the OLT setting unit 52 to identify the VOLTHA frame of the physical port P1.
Similarly, the VID value of 101 is an index for the OLT setting unit 52 to identify the VOLTHA frame of the physical port P2, and the VID value of 102 is an index for the OLT setting unit 52 to identify the VOLTHA frame of the physical port P3.

S13) Transfer rule determination processing The switch control unit 53 sets the downlink and uplink transfer rules of the VOLTHA frame as the following transfer rules D1 and U1, respectively, based on the VID values of the preconditions S11 and S12.

(Transfer rule D1): When a communication frame with a downlink VID value = 101 is received in Q2
→ Overwrite VID value = 4092 and transfer to P1 When a communication frame with VID value = 102 is received in Q2
→ Overwrite VID value = 4092 and transfer to P2 When a communication frame with VID value = 103 is received in Q2
→ Overwrite VID value = 4092 and transfer to P3

(Transfer rule U1): When a communication frame having an uplink VID value = 4092 is received by P1.
→ Overwrite VID value = 100 and transfer to Q2 When a communication frame with VID value = 4092 is received by P2
→ Overwrite VID value = 101 and transfer to Q2 When a communication frame with VID value = 4092 is received by P3
→ Overwrite VID value = 102 and transfer to Q2

When the setting process of step S1 described above is completed, the OLT setting unit 52, which is physically a one-to-many correspondence (Q2: P1 to P3), and the plurality of OLT1X to 1Z are logically one-to-one. Since it is associated with the correspondence relationship (100Q2, 101Q2, 102Q2: 4092P1, 4092P2, 4092P3), the OLT setting unit 52 can uniquely identify a plurality of OLT1X to 1Z.

Therefore, when the setting process of step S1 is completed, the OLT setting unit 52 and the plurality of OLT1X to 1Z can perform control communication using the VOLTHA frame.
Therefore, the OLT setting unit 52 inquires about the LLID value of ONU2 registered in each of the OLT1X to 1Z by the VOLTHA frame, collects the value, and notifies the switch control unit 53 of the collected LLID value (step T2).

Here, for example, it is assumed that there are two ONU2s registered in OLT1X to 1Z, and the LLID values of those ONU2s are as follows.
LLID value of ONU2 of OLT1X → a1, a2
LLID value of ONU2 of ONU1Y → b1, b2
LLID value of ONU2 in OLT1Z → c1, c2

(Step S2: Setting process of forwarding rule regarding DBA)
Under the following preconditions S21 and S22, the switch control unit 53 executes the next transfer rule determination process S23 in response to an operation input to the operation unit 44.

S21) VID value between switch / OLT (prerequisite)
A communication frame having a common VID value = 4091 set as a reserved value in each OLT1 is used as a DBA frame. The VID value is recorded in, for example, the ROM of OLT1.
Therefore, the VID value of 4091 is uniformly used as an index representing the DBA frame regardless of the port number i of the physical port Pi. Note that "4091" is an example, and any value other than the reserved value can be adopted.

S22) VID value between DBA / switch (prerequisite)
A communication frame having a VID value different for each port number i of the physical port Pi, which is recorded as a reserved value in the storage unit 42 of the general-purpose server 4, is referred to as a DBA frame. For example, the communication frame of the next VID value is a DBA frame.
VID value for port P1 (OLT1X) → 100
VID value for port P2 (OLT1Y) → 101
VID value for port P3 (OLT1Z) → 102

Therefore, the VID value of 100 is an index for the middleware unit 48 to identify the DBA frame of the physical port P1.
Similarly, the VID value of 101 is an index for the middleware unit 48 to identify the DBA frame of the physical port P2, and the VID value of 102 is an index for the middleware unit 48 to identify the DBA frame of the physical port P3.

In the example of FIG. 4, the OLT setting unit 52 and the middleware unit 48 are connected to different physical ports Q2 and Q3. Therefore, the VID value of the VOLTHA frame and the VID value of the DBA frame on the upper side of the switch are both 100 to 102.
However, when the OLT setting unit 52 and the middleware unit 48 are connected to the same physical port Q2, in order to logically distinguish the VOLTHA frame and the DBA frame, the range of the VID values of both may be defined in different ranges.

S23) Transfer rule determination processing The switch control unit 53 sets the downlink and uplink transfer rules of the DBA frame as the following transfer rules D2 and U2, respectively, based on the VID values of the prerequisites S21 and S22.
More specifically, the transfer rule of the batch gate is set to the next transfer rule D2, and the transfer rule of the batch report is set to the next transfer rule U2.

(Transfer rule D2): Downward direction (collective gate)
When a communication frame with VID value = 101 is received in Q3
→ Overwrite VID value = 4091 and transfer to P1 When a communication frame with VID value = 102 is received in Q3
→ Overwrite VID value = 4091 and transfer to P2 When a communication frame with VID value = 103 is received in Q3
→ Overwrite VID value = 4091 and transfer to P3

(Transfer rule U2): Upward direction (collective report)
When a communication frame with VID value = 4091 is received by P1
→ Overwrite VID value = 100 and transfer to Q3 When a communication frame with VID value = 4091 is received by P2
→ Overwrite VID value = 101 and transfer to Q3 When a communication frame with VID value = 4091 is received by P3
→ Overwrite VID value = 102 and transfer to Q3

When the setting process of step S2 described above is completed, the middleware unit 48, which is physically in a one-to-many correspondence relationship (Q3: P1 to P3), and a plurality of OLT1X to 1Z have a logical one-to-one correspondence. Since it is associated with the relationship (100Q3, 101Q3, 102Q3: 4091P1, 4091P2, 4091P3), the middleware unit 48 can uniquely identify a plurality of OLT1X to 1Z.

Therefore, when the setting process of step S2 is completed, the middleware unit 48 and the plurality of OLT1X to 1Z can perform control communication using the DBA frame.
Therefore, the middleware unit 48 inputs the batch report received from each of the OLTs 1X to 1Z into the DBA application 49A, and causes the bandwidth allocation calculation for each of the OLTs 1X to 1Z to be executed. Further, the middleware unit 48 transmits a batch gate including allocation results (grant information) for each OLT 1X to 1Z to each OLT 1X to 1Z, respectively.

(Step S3: Setting process of transfer rule regarding main signal)
The switch control unit 53 executes the next VID value allocation process S31 and the next transfer rule determination process S32 using the LLID value notified from the OLT setting unit 52.

S31) VID value allocation process S31
The switch control unit 53 assigns a VID value of a different value for each LLID value of each OLT1X to 1Z, and uses a communication frame including those VID values as a main signal (user frame).
This VID value has a one-to-one correspondence with the LLID value, and is, for example, the same value on the upper side and the lower side of the concentrator 3. The numerical range of the VID value is a range excluding the reserved value and the VID value (= 100 to 102) for the OLT setting unit 52 and the middleware unit 48.

In the example of FIG. 4, the following VID values are assigned by the above allocation process S31.
LLID value = a1 → VID value = x1 of OLT1X (port P1)
LLID value = a2 → VID value = x2 of OLT1X (port P1)
LLID value = b1 → VID value = y1 of OLT1Y (port P2)
LLID value = b2 → VID value = y2 of OLT1Y (port P2)
LLID value = c1 → VID value = z1 of OLT1Z (port P3)
LLID value = c2 → VID value = z2 of OLT1Z (port P3)

However, the VID value for the user frame may have a one-to-one correspondence between the upstream side and the lower side of the concentrator 3, and may be different values on the upper side and the lower side. The result of the allocation process S31 in this case is as follows, for example.
LLID value of OLT1X (port P1) = a1
→ VID value of port P1 = x1 → VID value of port Q4 = x11
LLID value of OLT1X (port P1) = a2
→ VID value of port P1 = x2 → VID value of port Q4 = x12

LLID value of OLT1Y (port P2) = b1
→ VID value of port P2 = y1 → VID value of port Q4 = y11
LLID value of OLT1Y (port P2) = b2
→ VID value of port P2 = y2 → VID value of port Q4 = y12
LLID value of OLT1Z (port P3) = c1
→ VID value of port P3 = z1 → VID value of port Q4 = z11
LLID value of OLT1Z (port P3) = c2
→ VID value of port P3 = z2 → VID value of port Q4 = z12

S33) Transfer rule determination process The switch control unit 53 sets the transfer rules of the main signal (user frame) in the downlink direction and the uplink direction as the following transfer rules D3 and U3, respectively.

(Transfer rule D3): When a communication frame having a downlink VID value = x1 and x2 is received in Q4.
→ Transferred to P1 without overwriting the VID value or executing the tag operation When a communication frame with VID value = y1 and y2 is received in Q4
→ Transferred to P2 without overwriting the VIDEO value or executing the tag operation When a communication frame with VID value = z1 or z2 is received in Q4
→ Transfer to P3 without overwriting the VIDEO value or executing the tag operation

(Transfer rule U3): When a communication frame with uplink VID value = x1 and x2 is received by P1.
→ Transferred to Q4 without overwriting the VID value or executing the tag operation When a communication frame with VID value = y1 and y2 is received by P2
→ Transferred to Q4 without overwriting the VIDEO value or executing the tag operation When a communication frame with VID value = z1 and z2 is received by P3
→ Transfer to Q4 without overwriting the VIDEO value or executing the tag operation

The switch control unit 53 notifies the OLT setting unit 52 of the “ID correspondence information” that represents the correspondence between the LLID value and the VID value for each of the OLT1X to 1Z obtained by the allocation process S31.
The OLT setting unit 52 that has received the ID correspondence information generates a VOLTHA frame addressed to each of the OLT1X to 1Z including the ID correspondence information, and transmits the generated VOLTHA frame to each of the OLT1X to 1Z (step T2).

Specifically, the OLT setting unit 52 includes the ID correspondence information for the OLT1X in the communication frame (VOLTHA frame) having the VID value = 100, and transmits the frame to the concentrator device 3.
Similarly, the OLT setting unit 52 stores the ID correspondence information for the OLT1Y in the communication frame (VOLTHA frame) having the VID value = 101, and transmits the frame to the concentrator 3. The OLT setting unit 52 stores ID correspondence information for OLT 1Z in a communication frame (VOLTHA frame) having a VID value = 102, and transmits the frame to the concentrator device 3.

[Summary of forwarding rules]
FIG. 5 is a table summarizing the transfer rules D1 to D3 and U1 to U3 of the communication frame applied to the concentrator 3 according to the setting procedure of FIG.
In FIG. 5, the processing content described in the thick arrow is the processing content executed by the concentrator 3 on the VLAN tag of the communication frame when the communication frame is transferred.

As shown in FIG. 5, when the concentrator 3 transfers a control frame composed of a VOLTHA frame or a DBA frame between physical ports Pi / Q2 (or Q3), the concentrator 3 sets a pair of VID values of communication frames before and after the transfer. Associate with many.
Specifically, as shown in the transfer rules D1, D2, U1, U2, the VID value is converted by overwriting the VID value at the time of frame transfer.

On the other hand, when the main signal (user frame) is transferred between the physical ports Pi / Q4, the concentrator 3 associates the VID values of the communication frames before and after the transfer on a one-to-one basis.
Specifically, as shown in transfer rules D3 and U3, the VID value is converted by overwriting the VID value at the time of frame transfer. However, if the VID values of the receive port and the transmit port are the same, the one-to-one correspondence is maintained even if the VID value is not converted during frame transfer, so there is no need to execute an overwrite operation on the VLAN tag. Good.

[Transfer route of communication frame]
FIG. 6 is an explanatory diagram showing an example of a transfer path of a communication frame by the concentrator 3.
In the example of FIG. 6, the path indicated by the solid arrow in the concentrator 3 is the transfer path of the VOLTHA frame, and the path indicated by the virtual line arrow in the concentrator 3 is the transfer path of the main signal (user frame). .. That is, FIG. 6 is a route diagram when the transfer path of the VOLTHA frame and the transfer path of the main signal are superimposed.

As shown in FIG. 6, the OLT 1X to 1Z include a setting processing unit (also referred to as a “VOLTHA processing unit”) 21 and an ID conversion table 22.
When the setting processing unit 21 receives a communication frame (VOLTHA frame) having a VID value = 4092 including ID correspondence information, the setting processing unit 21 updates the ID conversion table 22 of its own device. When transferring the user frame, the OLT 1X to 1Z refer to the ID conversion table 22 and execute the identification information conversion process.

Specifically, when the OLT1X to 1Z transmit the user frame received from the PON line in the uplink, the VID value corresponding to the LLID value of the received frame is extracted from the ID conversion table 22, and the extracted VID value is used as the transmission frame. It is attached to the VLAN tag of.
On the contrary, when the OLT1X to 1Z transmit the user frame received from the concentrator 3 in the downlink, the LLID value corresponding to the VID value of the received frame is extracted from the ID conversion table 22, and the extracted LLID value is used in the transmission frame. Add to the header.

FIG. 7 is an explanatory diagram showing another example of the transfer path of the communication frame by the concentrator 3.
In the example of FIG. 7, the path indicated by the solid arrow in the concentrator 3 is the transfer path of the DBA frame, and the path indicated by the virtual line arrow in the concentrator 3 is the transfer path of the main signal (user frame). .. That is, FIG. 7 is a route diagram when the transfer path of the DBA frame and the transfer path of the main signal are superimposed.

As shown in FIG. 7, the OLT 1X to 1Z include a message processing unit 18.
The message processing unit 18 collects the upward transmission request amount of each ONU2 from the plurality of report frames received in the DBA cycle, and generates a communication frame (batch report) having a VID value = 4091.
The message processing unit 18 includes the collected transmission request amount of each LLID in the batch report, and transmits the batch report to the line concentrator 3.

When the message processing unit 18 receives a communication frame (batch gate) having a VID value = 4091 from the concentrator 3, it extracts grant information of each ONU2 from the received batch gate and generates a gate frame for each ONU2.
The message processing unit 18 includes the extracted grant information of each ONU2 in the gate frame corresponding to each ONU2, and sends the gate frame to the PON line.

[OLT hardware configuration]
FIG. 8 is a block diagram showing an example of the hardware configuration of OLT1.
As shown in FIG. 8, the OLT 1 includes a lower transmission / reception unit 11, a frame processing unit 12, and an upper transmission / reception unit 13 in this order from the left side to the right side of the figure.

The lower transmission / reception unit 11 is a signal transmission / reception device including an optical transceiver.
The lower transmission / reception unit 11 converts the uplink light signal from the ONU 2 into an electric signal. The lower transmission / reception unit 11 outputs the uplink frame reproduced from the converted electric signal to the uplink reception processing unit 14 of the frame processing unit 12.
The lower transmission / reception unit 11 converts the downlink frame input from the downlink transmission processing unit 17 of the frame processing unit 12 into a downlink optical signal in a predetermined wavelength band. The lower transmission / reception unit 11 transmits the converted downlink light signal to the PON line.

The upper transmission / reception unit 13 is an Ethernet signal transmission / reception device.
The upper transmission / reception unit 13 demodulates the Ethernet signal input from the concentrator 3 and reproduces the downlink frame. The upper transmission / reception unit 13 outputs the reproduced downlink frame to the downlink reception processing unit 16 of the frame processing unit 12.
The upper transmission / reception unit 13 modulates the uplink frame input from the uplink transmission processing unit 15 of the frame processing unit 12 into an Ethernet signal having a predetermined frequency. The upper transmission / reception unit 13 transmits the modulated Ethernet signal to the line concentrator 3.

The frame processing unit 12 is composed of an integrated circuit such as an FPGA (Field-Programmable Gate Array) having a MAC function. The frame processing unit 12 may include a part of the functions of the PHY layer, or may be partially or wholly composed of an integrated circuit such as an ASIC (Application Specific Integrated Circuit).

The frame processing unit 12 includes an uplink reception processing unit 14, an uplink transmission processing unit 15, a downlink reception processing unit 16, a downlink transmission processing unit 17, and a message processing unit 18.
Further, the frame processing unit 12 includes an uplink buffer 19, a downlink buffer 20, a setting processing unit (VOLTHA processing unit) 21, and an ID conversion table 22.

If the uplink frame input from the lower transmission / reception unit 11 is a user frame, the uplink reception processing unit 14 outputs the frame to the uplink buffer 19.
At this time, the uplink reception processing unit 14 executes ID conversion from the LLID value to the VIDEO value with reference to the ID conversion table 22, and adds a VLAN tag including the converted VIDEO value to the user frame.

The uplink transmission processing unit 15 takes out a user frame from the uplink buffer 19 and outputs it to the upper transmission / reception unit 13. The upper transmission / reception unit 13 converts the input user frame into an Ethernet signal and transmits it to the concentrator 3.
The types of uplink frames processed by the uplink transmission processing unit 15 include three types: VOLTHA frames, batch reports, and user frames. For example, it is preferable that the uplink transmission processing unit 15 sets the transmission priority of those types to VOLTHA frame> report frame> user frame.

If the downlink frame input from the higher transmission / reception unit 13 is a user frame, the downlink reception processing unit 16 outputs the frame to the downlink buffer 20.
At this time, the downlink reception processing unit 16 executes ID conversion from the VID value to the LLID value with reference to the ID conversion table 22, and writes the converted LLID value in the header of the user frame.

The downlink transmission processing unit 17 takes out a user frame from the downlink buffer 20 and outputs it to the lower transmission / reception unit 11. The lower transmission / reception unit 11 converts the input user frame into a downlink light signal and transmits it to ONU2.
The types of downlink frames processed by the downlink transmission processing unit 17 include two types, a gate frame and a user frame. The downlink transmission processing unit 17 preferably sets, for example, the transmission priority of those types to gate frame> user frame.

If the uplink frame input from the lower transmission / reception unit 11 is the ONU2 report frame, the uplink reception processing unit 14 outputs the frame to the message processing unit 18.
The message processing unit 18 takes out the transmission request amount of ONU2 in the upward direction from the report frame, and holds the taken-out transmission request amount in a buffer (not shown). The message processing unit 18 generates a communication frame (batch report) having a VID value = 4091 for each predetermined DBA cycle, and includes the held transmission request amount of each ONU2 in the batch report. The message processing unit 18 outputs a batch report including the transmission request amount of each ONU 2 to the uplink transmission processing unit 15.

When the downlink frame input from the upper transmission / reception unit 13 is a communication frame (batch gate) having a VID value = 4091, the downlink reception processing unit 16 outputs the frame to the message processing unit 18.
The message processing unit 18 extracts the grant information (transmission start time and transmission time length) of each ONU2 from the input batch gate, and generates a gate frame addressed to each ONU2. The message processing unit 18 stores the grant information of the ONU2 in the gate frame addressed to each ONU2, and outputs the frame to the downlink transmission processing unit 17.

When the downlink frame input from the upper transmission / reception unit 13 is a communication frame (VOLTHA frame) having a VID value = 4092, the downlink reception processing unit 16 outputs the frame to the VOLTHA processing unit 21.
The VOLTHA processing unit 21 performs a predetermined setting process according to a command written on the VOLTHA frame. For example, when the command of the VOLTHA frame is a request for the LLID value, the VOLTHA processing unit 21 reads the registered LLID value of ONU2 from the ID conversion table 22 and includes the read LLID value in the VOLTHA frame for response. ..

When a new ONU2 is registered, the VOLTHA processing unit 21 transmits a VOLTHA frame including the LLID value of the new ONU2 to the OLT setting unit 52, and assigns a VOLT value for the user frame corresponding to the LLID value. Request to the setting unit 52.
Alternatively, the VOLT setting unit 52 periodically polls the VOLTHA processing unit 21 for a VOLTHA frame requesting the registration status of the ONU2, and the VOLTHA processing unit 21 obtains a new LLID value of the ONU2 in response to the request for the registration status. You may decide to respond.

When the VOLTHA frame includes new ID correspondence information, the VOLTHA processing unit 21 updates the contents of the ID conversion table 22 according to the notified ID correspondence information.
The VOLTHA frame is a communication frame that is terminated by OLT1 and returned to the OLT setting unit 52. Therefore, when the VOLTHA frame is input from the downlink reception processing unit 16, the VOLTHA processing unit 21 generates a communication frame (VOLTHA frame for response) having a VID value = 4092 and outputs it to the uplink transmission processing unit 15.

[Effect of this embodiment]
According to the PON system of the present embodiment, the control frame transmitted / received between the concentrator 3 and the plurality of OLT1X to 1Z is a communication frame containing a VID value (= 4092 or 4091) common to the plurality of OLT1X to 1Z. Therefore, the control frame transmitted / received between the OLT setting unit 52 or the middleware unit 48 of the general-purpose server 4 and the concentrator 3 is a communication frame containing a different VID value (= 100 to 102) for each physical port Pi for the OLT 1. Become.

Therefore, it is possible to logically associate the OLT setting unit 52 or the middleware unit 48, which has a one-to-many correspondence, with the plurality of OLT1X to 1Z in a one-to-one manner, and the OLT setting unit 52 or the middleware unit 48. Can uniquely identify a plurality of OLT1X to 1Z.
Therefore, the OLT setting unit 52 or the middleware unit 48 of the general-purpose server 4 appropriately executes control communication for a plurality of OLT1X to 1Z without using identification information unique to OLT1 such as a MAC address. Can be done.

According to the PON system of the present embodiment, the user frame transmitted / received between the concentrator 3 and the plurality of OLT1X to 1Z and the user frame transmitted / received at the user port Q3 are VIDs associated with the LLID value of ONU2. It consists of a communication frame containing a value.
Therefore, the ONU2 that is the source and destination of the user frame can be identified from the upper side of the line concentrator 3.

According to the PON system of the present embodiment, when the concentrator 3 transfers the control frame between the physical ports P / Q, the VID values of the communication frames before and after the transfer are associated one-to-many, and the user frame is associated with the physical port. When transferring between P / Q, the tag information of the communication frame before and after the transfer is associated with each other on a one-to-one basis (see FIG. 5). The reason is as follows.

The VID value (= 4092 or 4091) of the control frame on the OLT1 side is a common value, and the VID value (= 100 to 102) of the control frame on the OLT setting unit 52 side or the middleware unit 48 side is the physical ports P1 to P3. This is because the VID values need to be associated one-to-many at the time of transfer for the control frame because there are a plurality of values corresponding to.
Since the VID value of the user frame is a value corresponding to the identification information (LLID value) of ONU2 on the upper side and the downstream side of the concentrator 3, the VID value is associated with each other on a one-to-one basis at the time of transfer. Because it is necessary.

According to the PON system of the present embodiment, the general-purpose server 4 has an OLT setting unit 52 which is a software component for realizing the setting related to the PON communication, and the control frame is set to be required for the setting related to the PON communication. A setting frame for transmitting information (for example, a VOLTHA frame) is included.
Therefore, the general-purpose server 4 can appropriately set a plurality of OLTs 1X to 1Z connected to the concentrator 3 by operating the OLT setting unit 52 according to the setting information obtained in the setting frame.

According to the PON system of the present embodiment, the general-purpose server 4 has an application component 49 (for example, DBA application 49A) for realizing a part of the PON function, and is required for some functions in the control frame. A functional frame for transmitting various functional information is included.
Therefore, the general-purpose server 4 substitutes some functions such as DBA for a plurality of OLT1X to 1Z connected to the line concentrator 3 by operating the application component 49 based on the function information obtained in the function frame. Can be done.

According to the OLT setting unit 52 or the middleware unit 48 (computer program) of the present embodiment, among a plurality of OLT1X to 1Z, based on the VID value (= 100 to 102) which is the tag information stored in the storage unit 42. Since the control frame for which OLT1 is identified, the general-purpose server 4 can uniquely identify a plurality of OLTs 1X to 1Z.
Therefore, control communication for a plurality of OLT1X to 1Z can be appropriately executed without using identification information unique to OLT1 such as a MAC address.

[Other variants]
It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present invention is indicated by the scope of claims, and it is intended that all modifications within the meaning and scope equivalent to the scope of claims are included.

For example, in the above-described embodiment, the application component 49, the OLT setting unit 52, and the switch control unit 53 may be software components installed on different computers (general-purpose servers).
Further, two of the above three types of software components may be installed on the first computer (first general-purpose server), and the remaining one may be installed on another second computer (second general-purpose server). ..

In the above-described embodiment, the general-purpose server (communication device) 4 including at least one of the switch control unit 53, the OLT setting unit 52, and the middleware unit 48 is not directly connected to the line concentrator 4, but is a network or relay device. It may be connected to the line concentrator 3 via.
In the above-described embodiment, the physical ports Q2 to Q4 of the concentrator 3 may be integrated into one or two physical ports. When the physical ports Q2 to Q4 are integrated in this way, it is necessary to exclusively allocate the VID value according to the type of communication frame.

In the above-described embodiment, the VID value described in the VLAN tag is used as the tag information that logically identifies the type of the communication frame, but the tag information is described in another information area included in the communication frame. It may be a value to be set, or a value described in a predetermined information area uniquely defined in the communication frame.

In the above-described embodiment, the operation unit 44 and the display unit 45 used by the operator do not necessarily have to be directly connected to the housing 40 itself of the general-purpose server 4.
For example, when the OS 47 or middleware unit 48 of the general-purpose server 4 has a remote control function, the general-purpose server 4 is logged in from another PC away from the general-purpose server 4, and the operation unit 44 and the display unit 45 of the PC are displayed. It may be used to perform a predetermined operation input.

1 Optical network unit (OLT)
1X ~ 1Z small OLT
2 Optical network unit (ONU)
3 Concentrator (L2SW)
4 General-purpose server (communication device)
5 Upper device 11 Lower transmission / reception unit 12 Frame processing unit 13 Upper transmission / reception unit 14 Uplink reception processing unit 15 Uplink transmission processing unit 16 Downward reception processing unit 17 Downstream transmission processing unit 18 Message processing unit 19 Upstream buffer 20 Downstream buffer 21 Setting processing Part (VOLTHA processing part)
22 ID conversion table 40 Housing 41 Control unit 42 Storage unit 43 Communication unit 44 Operation unit 45 Display unit 46 Computer program (software)
47 OS
48 Middleware section 49 Application parts (application parts)
49A DBA App 49B Power Saving App 49C OAM App 50 Internal API
50A-50C Internal API
51 External API
51A-51C External API
52 OLT setting unit 53 Switch control unit 54 External API
55 External API

Claims (8)

Multiple station-side termination devices that terminate the corresponding PON line,
A communication device that performs control communication using the plurality of station-side termination devices and a control frame, and
A PON system including a concentrator device to which the plurality of station-side termination devices and the communication device are connected.
The control frame communicated between the concentrator and the plurality of station-side termination devices is
It is the first frame below,
The control frame communicated between the communication device and the line concentrator is
The PON system which is the second frame below.
First frame: Communication frame containing the first tag information common to a plurality of station-side terminal devices Second frame: Communication including a second tag information different for each physical port of the concentrator to which a plurality of station-side terminal devices are connected. flame The line concentrator
It has a user port, which is the physical port to which the host device is connected.
The user frame communicated between the concentrator and the plurality of station-side termination devices and the user frame communicated at the user port are
The PON system according to claim 1, which is the third frame below.
Third frame: A communication frame containing the third Doug information associated with the identification information of the subscriber side termination device of the PON line. The line concentrator
When transferring the control frame between physical ports, the tag information of the communication frame before and after the transfer is associated one-to-many.
The PON system according to claim 2, wherein when the user frame is transferred between physical ports, the tag information of the communication frame before and after the transfer is associated with each other on a one-to-one basis. The communication device is
It has software components to realize settings related to PON communication.
The control frame
The PON system according to any one of claims 1 to 3, which includes a setting frame for transmitting setting information necessary for the setting. The communication device is
It has software components to realize some functions of PON function,
The control frame
The PON system according to any one of claims 1 to 4, wherein a functional frame for transmitting functional information necessary for some of the functions is included. The upper transmitter / receiver connected to the concentrator and
The lower transmitter / receiver connected to the PON line and
A station-side termination device including a communication device connected to the line concentrator and a frame processing unit that performs control communication using a control frame.
The concentrator
At least one other station-side termination device other than the own device can be connected,
The control frame communicated between the concentrator and the plurality of station-side termination devices including the own device is a station-side termination device including a communication frame including the first tag information common to the plurality of station-side termination devices. The communication unit connected to the concentrator and
A communication device including a plurality of station-side termination devices connected to the concentrator device and a control unit that performs control communication using a control frame.
The control frame communicated between the concentrator and the plurality of station-side termination devices is
A communication device including a communication frame including a second tag information different for each physical port of the line concentrator to which the plurality of station-side termination devices are connected. A computer program that functions a computer as a communication device that performs control communication using a control frame with a plurality of station-side termination devices connected to a line concentrator.
A step of storing different tag information for each physical port of the concentrator to which the plurality of station-side termination devices are connected, and
A computer program including a step of identifying which station-side termination device of the plurality of station-side termination devices is the control frame based on the stored tag information.

Images