JP5683243B2 - PON parent device - Google Patents

Description

  The present invention includes an OLT (Optical Line Terminal) that is an in-station device that performs communication via an optical branching device, and an ONU (Optical Network Unit) that is a plurality of terminal devices connected to the branch destination of the OLT. The present invention relates to a communication system using a PON (Passive Optical Network) system.

  As a subscriber optical fiber network system for subscriber homes such as general homes, OLT, which is a PON parent device installed at the station building side, and ONU, which is a PON slave device installed at multiple subscriber homes Of optical fiber, one optical fiber connected to the OLT on the central office side is branched into multiple optical couplers that are passive elements, and the ONUs on each subscriber's home side are branched to the branch destinations. The connection method is called a PON method. This method has been put to practical use as a method capable of performing high-speed data transmission to a plurality of ONUs without providing a relay device or the like in the middle of the transmission path.

  In the system using the PON system, the OLT on the station side converts the data from a higher-level device that distributes information into an optical signal, sends it to the ONU on the subscriber's home side, and sends it from the ONU as an optical signal. This is a device that performs data conversion and communication control such as sending received data to a host device. The OLT can communicate with ONUs installed on a plurality of subscriber premises, and an optical fiber connected to the OLT is branched by an optical coupler provided in the middle of the transmission path. Each of the branched optical fibers is drawn into an individual subscriber premises and connected to the ONU. The ONU is a device that performs communication control such as communication with the OLT, conversion between an optical signal and an electric signal, and communication with a terminal device such as a computer. Data transmission is performed bidirectionally by wavelength multiplexing using a single optical fiber. For example, the downlink data from the OLT on the station building side to the ONU on the subscriber premises side is transmitted as an optical signal with a wavelength of 1.5 μm, and the uplink data from the ONU to the OLT is transmitted as an optical signal with a wavelength of 1.3 μm. . The optical coupler distributes a downstream signal from one optical fiber to a plurality of optical fiber branch lines, aggregates upstream signals from the plurality of optical fiber branch lines into one optical fiber, and is a passive element. Distribution and aggregation of optical signals is possible only with couplers.

  FIG. 1 is a schematic diagram showing a configuration example of a system using a PON system. As shown in FIG. 1, the PON system includes an OLT 1 that is an intra-office device on the operation manager side connected to the higher level network 9, ONU 2 and OLT 1 that are end devices on the user side connected to each user terminal device 6, and a plurality of them. The optical fiber trunk line 3 and a plurality of optical fiber branch lines 5 are connected to the ONU 2 via an optical coupler (optical branching device) 4. Further, when the ONU 2 accommodates a plurality of services such as an apartment house, the line concentrator 7 is used.

  In a communication apparatus using such a PON system, a plurality of ONUs communicate with the OLT using MPCP (Multi-point control protocol). In this state, when an optical fiber trunk disconnection error or a local power failure occurs, and when trying to recover from a state in which multiple ONUs are cut off at the same time, the ONU starts link-up at random and communicates from the ONU that has completed link-up. Bandwidth is allocated.

Japanese Patent No. 4488719

  However, in the conventional PON system, for example, a plurality of services are accommodated in a specific ONU, and even if it is desired to recover from the specific ONU preferentially, the link is randomly linked regardless of that. Since the ONU that has started up is restored, there is a problem that the restoration of the ONU that is preferentially restored is postponed.

  The present invention has been made to solve the above-described problems, and in a PON system, recovery is performed from an important communication service line by performing authentication from a high-priority ONU after link-up. It is an object to provide an OLT capable of performing the above.

In order to achieve the above object, according to the present invention, in the PON parent device of the PON system in which the PON parent device and the plurality of PON child devices are connected via the optical branching device, the authentication information of each of the plurality of PON child devices is prioritized. An authentication information database stored in association with the rank information and a timer for monitoring a time for performing authentication of the PON slave device, and acquired from the plurality of PON slave devices when the PON system is recovered after communication disconnection The authentication information is compared with the authentication information database, and the PON slave devices are sequentially authenticated in accordance with the priority information stored in the authentication information database, and the authentication of the PON slave device is completed even when the timer expires. If you do not, skip the authentication of the PON terminal device, the authentication information database, a large number of connected user terminals And wherein the storing the higher the the authentication information priorities of the serial PON terminal device.

  According to the present invention, even when a reconnection request is received from the plurality of ONUs almost simultaneously at the time of recovery from a state in which the communication of the plurality of ONUs is interrupted due to an optical fiber trunk disconnection or a local power failure, Authentication can be started from the ONU of a high priority service such as a residential line and the communication service can be recovered, and differentiation for each service can be performed.

It is the schematic which shows the structure of a PON system. It is a figure which shows schematic structure of the PON system in Embodiment 1, and an ONU authentication database. 6 is a diagram showing an authentication sequence of the PON system in the first embodiment. FIG. It is a figure which shows the ONU authentication database of the PON system in Embodiment 2. FIG.

Embodiment 1 FIG.
Hereinafter, embodiments of the present invention will be described with reference to the drawings. As described above, FIG. 1 is a schematic diagram illustrating a configuration example of a system using the PON method. As shown in FIG. 1, the system using the PON system includes an OLT 1 that is an intra-office device on the operation manager side connected to the upper network 9 and an ONU 2 that is a user-side termination device connected to each user terminal device 6. , OLT 1 and a plurality of ONUs 2 are configured by one optical fiber trunk line 3 and a plurality of optical fiber branch lines 5 that connect an optical coupler (optical branching device) 4. The optical fiber trunk line 3, the optical coupler 4, and the plurality of optical fiber branch lines 5 physically connect the OLT 1 that is a station-side PON parent device and the ONU 2 that is a plurality of subscriber-side PON child devices by passive elements. It becomes a connectable transmission line.

  A system using the PON system is basically composed of 1 to 5 described above, and the OLT 1 performs control for allocating a communication band to each ONU 2 in real time, so that even if the transmission path is only a passive element. One-to-N communication is enabled. The user terminal device 6 is connected under the control of the ONU 2 and is, for example, a computer for receiving provision of Internet services, an intelligent meter for performing information collection notification of meter reading services, and a terminal for accommodating telephone services. An adapter etc. corresponds to it. Further, when the ONU 2 is installed in a place such as a housing complex and accommodates a plurality of end user services, the concentrator 7 is used.

  FIG. 2 is a block diagram showing a schematic configuration of a system using the PON system in the first embodiment, and also shows contents of the ONU authentication database held by the OLT. The ONU authentication database 11 shown in FIG. 2 is a database in which child ID numbers, MAC addresses, and priority information of ONUs are associated with each other.

  The OLT 1 is connected to an upper network 9 such as the Internet, and is connected to a control terminal 8 that performs ON / OFF setting of an automatic registration function. The ONU 2 converts the optical signal from the OLT 1 into an electric signal and gives it to the user terminal 6, and converts the electric signal from the user terminal 6 into an optical signal and transfers it to the OLT 1. On the other hand, the OLT 1 transfers the optical signal from the ONU 2 to the upper network 9 and transfers the signal from the upper network 9 to the ONU 2 and monitors the PON section and the ONU 2.

  Next, authentication / registration when the ONU 2 is connected to the PON system and used will be described. The OLT 1 automatically registers the MAC address of the ONU in the ONU authentication database 11 when the ONU 2 starts communication. Further, the operator uses the control terminal 8 to change or delete the ONU authentication database 11 and set the automatic registration function to ON / OFF. Note that the automatic registration function is set to “invalid (OFF)” when security is increased, but is set to “valid (ON)” when automatic registration is performed.

  FIG. 3 is a diagram showing an authentication sequence of the system using the PON method in the first embodiment. First, when the ONU 2 is linked up to the OLT 1, the OLT 1 requests the ONU 2 to acquire the MAC address together with the child ID number, and determines whether or not the acquired MAC address exists in the ONU authentication database 11 ( Step ST31).

  Here, when the MAC address does not exist in the ONU authentication database 11, such as when the ONU 2 is linked up for the first time, the OLT 1 determines whether or not the automatic registration function is set to ON (valid) (step ST32). If it is ON (valid), the normality of the acquired child ID number (having a value within a predetermined range) and the duplication with the child ID number of another ONU are checked ( Step ST33). If the child ID number is normal and there is no duplication, an entry is added to the ONU authentication database 11 for the child ID number and MAC address of the ONU 2 (step ST34). On the other hand, if the automatic registration function is OFF (invalid) in step ST32, or if the child ID number is invalid or duplicated with the child ID number of another ONU in step ST33, The port of ONU2 is closed to make it non-conductive.

  Further, when the ONU 2 is linked up after the second time or the like, and the MAC address of the ONU 2 exists in the ONU authentication database 11 in the determination of step ST31, the OLT 1 uses the MAC address of the ONU 2 as a key. The child ID number registered in the ONU authentication database 11 is read, and the read child ID number is collated with the child ID number acquired from the ONU 2 (step ST35).

  Conventionally, when the child ID numbers match in this step ST35, the port is opened to enable conduction, and when the child ID numbers do not match, the port is closed to disable conduction. In addition, these sequences are performed in the order of the linked-up ONUs.

On the other hand, in the authentication sequence according to the first embodiment of the present invention, after collating with the child ID number in step ST35, the priority order is further collated using the ONU authentication database 11 (step ST36). If the priority of the ONU 2 to be authenticated is not the highest, that is, if it is found that an ONU having a higher priority than the ONU 2 remains unauthenticated, the ONU 2 to be authenticated Reset or disconnect the link, and then initialize it to postpone the authentication process. On the other hand, if it is determined that the ONU 2 is the highest priority ONU at the time of the priority order collation in step ST36, the port is opened and conduction is permitted.
By repeating this sequence, authentication is completed in order from the ONU with the highest priority, and the service is resumed.

  As described above, according to the first embodiment of the present invention, when an optical fiber trunk disconnection abnormality, a regional power failure, etc. occur and a plurality of ONUs 2 attempt to recover from a state where communication is interrupted simultaneously, Authentication can be completed preferentially from an ONU having a high priority that accommodates the service of the end user, and the service can be resumed.

  This embodiment accommodates the services of a plurality of end users under the ONU (32) in the ONU 2 of FIG. 1, for example. This is particularly effective as a method for preferentially completing authentication from the ONU (32) that is expected to affect the end user of the user and restarting the service.

  Also, if the ONU with a high priority is faulty, or if it is difficult to restore the line because the end user has intentionally turned off the power to stop the service, the ONU with a low priority is excessive. A waiting time is set for each ONU by using a timer that monitors the authentication time so that service stagnation and deadlock do not occur. A mechanism for skipping the processing at the time of timeout may be provided.

Embodiment 2. FIG.
FIG. 4 is a diagram showing the ONU authentication database 12 in which the priority order in the ONU authentication database 11 in FIG. 2 is set as a group unit such as “high priority”, “medium priority”, and “low priority”. Since the other authentication sequences are the same as those in the first embodiment, detailed description thereof is omitted here.

  When authentication is performed using the ONU authentication database 12, the determination condition for permitting authentication is gentle compared to the method of assigning individual priorities to all the ONUs 2 as in the ONU authentication database 11. Even when the ONU 2 link-up order changes before and after the order in which authentication is to be preferentially performed, the number of post-authentication processes can be reduced. Therefore, there is an advantage that the total authentication completion and service resumption waiting time can be reduced as compared with the case of the first embodiment while priority control of re-authentication is performed at the time of service restoration.

Embodiment 3 FIG.
In the first embodiment, the child ID number of the ONU 2 can be used as the priority order. That is, a child ID number is assigned in advance from the ONU 2 with the highest priority, and a MAC address is registered in correspondence with the child ID number. Thereby, in the sequence shown in FIG. 3, after performing the collation process of step ST35, the priority is collated using the child ID number of the ONU authentication database (step ST36), and the child is more than the ONU 2 to be authenticated. If it turns out that an ONU with a small ID number (high priority) remains unauthenticated, the authentication process is performed by resetting or disconnecting the ONU 2 that is going to be authenticated and performing initialization. To postpone. On the other hand, when it is determined that the ONU 2 is the ONU having the smallest child ID number (high priority) at the time of the priority order collation in step ST36, the port is opened and conduction is permitted. By repeating this sequence, authentication is completed in order from the ONU with the highest priority, and the service is resumed.

  As described above, according to the third embodiment of the present invention, although there is a restriction on the assignment of the child ID number, the child ID number and the MAC address are obtained even if the ONU authentication database does not have individual data of priority. If there is a correspondence, priority control at the time of service restoration can be performed as in the first embodiment, and there is an advantage that the size of the authentication information database (ONU authentication database) can be reduced.

  In the present invention, within the scope of the invention, any combination of the embodiments, or any modification of any component in each embodiment, or omission of any component in each embodiment is possible. .

  DESCRIPTION OF SYMBOLS 1 OLT (station side PON master device) 2 ONU (subscriber PON side slave device) 3 Optical fiber trunk line 4 Optical coupler (optical branching device) 5 Optical fiber branch line 6 User terminal device 7 Concentrator , 8 Control terminal, 9 Host network, 11, 12 ONU authentication database (authentication information database).

Claims (2)

In a PON parent device of a PON system in which a PON parent device and a plurality of PON child devices are connected via an optical branching device,
An authentication information database storing authentication information of each of the plurality of PON slave devices in association with priority information;
A timer for monitoring time for performing authentication of the PON slave device,
When the communication of the PON system is recovered after disconnection, the authentication information acquired from the plurality of PON slave devices is collated with the authentication information database, and the PON slaves are sequentially ordered according to the priority information stored in the authentication information database. Authenticate the device,
If the authentication of the PON slave device is not completed even when the timer expires, the authentication of the PON slave device is skipped ,
The PON parent device , wherein the authentication information database stores the authentication information in which the priority order of the PON child devices having a large number of connected user terminals is increased . The authentication information database, the authentication information of a plurality of PON terminal apparatus included in a particular group, according to claim 1 Symbol placement of PON parent apparatus and to store in association with the same priority information.

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