KR100819265B1 - Method and optical network unit for passive optical network - Google Patents

Abstract

An ONU(Optical Network Unit) in a PON(Passive Optical Network) and a method for controlling the same are provided to previously intercept a wrong operation when an ONU works abnormally and to eliminate an effect having on another ONU which works normally. An ONU(20) in a PON comprises a power supply part(130), an optical module(110), a PON MAC(100), and a CPLD(Complex Programmable Logic Device)(120). The power supply part supplies power to the ONU. The optical module converts a data signal into an optical signal having a wavelength, uniquely allocated to each optical subscriber, according to an optical output control signal from the PON MAC and outputs the converted signal. The PON MAC exchanges messages for data transmission with an OLT(Optical Line Terminal)(10) according to an optical reception state from the optical module. The CPLD, which controls power supply to the optical module, comprises an optical output monitoring part(140) and a CPU(Central Processing Unit)(160). The optical output monitoring part confirms the registration state of the PON MAC from the OLT and controls the optical output and power of the optical module. The CPU request from the power supply part the supply or cut-off of the power to the optical module and the PON MAC.

Description

Optical subscriber device and control method in passive optical subscriber network {Method and Optical Network Unit for Passive Optical Network}

1A is a diagram illustrating the flow of downlink traffic in an Ethernet passive optical subscriber network according to the prior art.

1B is a diagram illustrating an upstream traffic flow in an Ethernet passive optical subscriber network according to the prior art.

2 is a diagram illustrating an optical subscriber device of a passive optical subscriber network according to a preferred embodiment of the present invention.

3 is a diagram illustrating an operation flow of a complex program logic controller according to an exemplary embodiment of the present invention.

* Description of the main drawing codes *

10: optical termination device 20: optical subscriber device

30: splitter 100: optical subscriber management unit

110: optical module 120: complex program logic control unit

130: power supply unit 140: light output monitoring unit

160: central processing unit

The present invention relates to an optical subscriber device and a control method of a passive optical subscriber network. More particularly, the optical subscriber device can block malfunctions in the event of an abnormal operation of the optical subscriber management unit and the optical module. The present invention relates to an optical subscriber device and a control method of a passive optical subscriber network that provides smooth service by blocking an influence on a subscriber device.

Currently, ASL (Asymmetric Digital Subscriber Line) and Cable Modem are most commonly used for high-speed Internet services. ADSL provides high speed internet service by using existing telephone line. It provides high speed service of 2Mbps ~ 10Mbps by installing ADSL modem in subscriber's computer.

Cable modems provide high-speed Internet service using coaxial cable installed for existing cable TV service. The cable modem should be installed in the PC while the subscriber is receiving cable TV service.

The high speed internet service has a much larger transmission capacity (2Mbps ~ 10Mbps) compared to the existing 56Kbps telephone line modem, and is satisfactory for providing services such as Internet web surfing (HTTP), e-mail, and file transfer (FTP). However, Voice over Internet Protocol (VoIP), Video on Demand (VoD), Internet broadcasting service, and the like have limitations to meet the requirements of newly added users. In addition, the cable modem high-speed Internet service has a disadvantage in that the available bandwidth decreases as the number of subscribers increases, and the ADSL type high-speed Internet service reduces the bandwidth that can be provided as the distance from the telephone company to the subscriber network increases. have.

To solve these shortcomings, Fiber To The Home (FTTH), Fiber To The Building (FTTB), and Fiber To The Curb (FTTC), which install fiber optic cables to subscriber networks, have been proposed. Research is underway on E-PON to improve.

E-PON is a network that combines Ethernet technology with only passive devices instead of using active devices that use power in optical subscriber networks to improve price competitiveness. The specification for E-PON is being produced by the Institute of Electrical and Electronics Engineers (IEEE) 802.3ah Ethernet in the first Mile Task Force. A display example of such an E-PON is attached to FIG. 1.

1A and 1B are diagrams illustrating flows of downlink and uplink traffic in an E-PON according to the related art.

As shown in Figure 1a and 1b, Ethernet passive optical subscriber network (E-PON) is a point-to-multi point structure, one optical line terminal (OLT), Hereinafter, several ONUs (optical subscriber units, hereinafter referred to as 'ONU', 20) are connected to a port through a splitter 30, which is a passive element. The data transfer between the OLT 10 and the ONU 20 is transmitted through an Ethernet frame, and the downstream from the OLT 10 to the ONU 20 is broadcasted to the data. The upstream signal from the ONU 20 to the OLT 10 uses a time division multiplexed access (TDMA) method to share the bandwidth allocated to several ONUs.

Accordingly, in transmitting the uplink signal to the OLT 10, the existing ONUs 20 receive IDLE data from the OLT 10 so as not to collide with each other through the burst mode. (The clock recovery time in the OLT and data for code group alignment) are first sent to the OLT 10, and then the uplink frame is transmitted according to the TDMA scheme.

In other words, each ONU 20-1, 20-2, and 20-3 transmits a frame to the OLT 10 based on a time division multiple access (TDMA) scheme. Each ONU 20-1, 20-2, 20-3 receives an allocation from the OLT 10 for a time (time slot) to transmit, and the ONU 20-1, 20-2, 20-3 receives Only the time (time slot) can transmit the corresponding frame. When the uplink transmission does not facilitate the control of the laser diode due to abnormal operation in any one of the ONUs 20-2, it is related to the laser diode control signal. Without this, the laser diode may interfere with the data transmission of other ONUs 20-1 and 20-3 in the case of light output.

This affects the time allotted for data transmission to other ONUs 20-1 and 20-3, and the ONU 20-2, which has failed, continues to occupy the transmission path and thus with the OLT 10. This can lead to a state in which normal data transfer is impossible.

It is an object of the present invention to provide an optical subscriber device and a control method which can block a malfunction in advance when an abnormal operation of an optical module occurs in a passive optical subscriber network.

Another object of the present invention is to block the effect on the other optical subscriber device in normal operation due to the abnormal operation of the optical subscriber management unit in the optical subscriber device.

In accordance with another aspect of the present invention, there is provided an optical subscriber device of a passive optical subscriber network, comprising: a power supply unit for supplying power to the optical subscriber device, and converting the optical signal into an optical signal having a wavelength uniquely assigned to each optical subscriber. Power supply of the optical module according to the registration state of the optical subscriber and the optical subscriber management unit for exchanging messages for data transmission from the optical module to the optical termination device according to the optical reception state from the optical module and the optical subscriber management unit. And a complex program logic control unit for controlling.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, in describing the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

First, before describing an embodiment of the present invention, the configuration of an optical subscriber device in a passive optical network (PON) to which the present invention is applied will be described with reference to FIG. 1. The passive optical subscriber network to which the present invention is applied is composed of one OLT 10 and a plurality of ONUs 20-1 to 20-3 connected to the OLT 10. In FIG. 1, three ONUs 20-1 to 20-3 are connected to one OLT 10. In addition, a plurality of end users (users, network devices, 40-1 to 40-3) may be connected to the ONUs 20-1 to 20-3.

When the first power is input and driven, the OLT 10 transmits a gate signal to all ONUs 20-1 to 20-3 to search for ONUs 20-1 to 20-3 connected through an optical communication medium. Send to.

The OLT 10 transmits a gate signal to the ONUs 20-1 to 20-3 at predetermined time intervals until a signal requesting registration is received. When the ONUs 20-1 to 20-3 receive the gate signal transmitted from the OLT 10 after the initial power is supplied and initialized, the ONUs 20-1 to 20-3 transmit a signal (registration request signal) requesting registration to the OLT 10.

When the OLT 10 receives the registration request signal transmitted from the ONUs 20-1 to 20-3, the OLT 10 registers the ONUs 20-1 to 20-3 and the ONUs 20-1 to 20-3. Grants LLID (Logical Link IDentification). The OLT 10 transmits a message regarding registration information and LLID allocation information of the ONUs 20-1 to 20-3 to the ONUs 20-1 to 20-3 (S140).

2 is a diagram illustrating an optical subscriber device of a passive optical subscriber network according to a preferred embodiment of the present invention.

Referring to FIG. 2, the optical subscriber device 20 of the passive optical subscriber network (PON) according to the present invention includes an optical subscriber management unit (PON MAC) 100, an optical module 110, and a complex program logic controller (COMPLEX PROGRAMMABLE LOGIC). DEVICE, hereinafter referred to as 'CPLD', 120), and a power supply 130.

When the first power is supplied from the power supply unit, the optical subscriber management unit (PON MAC) 100 initializes according to internal settings and sends a message for transmitting data with the OLT 10 from the optical module 110 connected through the optical communication medium. In this case, Time Division Multiple Access Medium Access Control Protocol (TDMA MAC) is used to access the medium while avoiding time duplication in uplink transmission to the OLT 10.

The optical module 110 converts the data signal into an optical signal having a wavelength uniquely assigned to each subscription in accordance with the optical power control signal from the optical subscriber management unit (PON MAC) 100 during uplink transmission to the OLT 10. Output

The complex program logic controller CPLD 120 includes an optical output monitor 140 and a central processor 160.

The light output monitoring unit 140 checks the initialization of the optical subscriber management unit 100 initially supplied from the power supply unit 130 or the re-registration attempt with the OLT 10 to initialize or re-register with the OLT 10. If the attempt is made, the optical subscriber management unit (PON, MAC, 100) requests the central processing unit (CPU) 160 not to directly control the optical module 110 for a predetermined time, and then the optical subscriber management unit (PON MAC, 100) from the OLT 10. Check the registration status to determine whether it is registered or not.

If the optical subscriber management unit (PON MAC) 100 is in a registered state during the time when the optical module 110 cannot be controlled by the light output monitoring unit 140, it is determined that the optical module 110 is not normally controlled and the OLT ( 10 to send an optical module 110 error signal to request the OLT 10 to send the corresponding information, and to turn off power to the optical module 110 and the optical subscriber management unit (PON MAC, 100). , 160).

On the other hand, the optical output monitoring unit 140, the optical subscriber management unit (PON MAC, 100) that is initially supplied from the power supply unit 130 is not initialized when the optical subscriber management unit (PON MAC, 100) is not in a normal state The determination is requested to the central processing unit (CPU) 160 to cut off the power of the optical subscriber management unit (PON MAC) 100 supplied through the power supply unit 130. This is because the optical subscriber management unit (PON MAC) 100 is not initialized and thus it is not possible to determine the abnormality of the optical module 110 in a normal manner. This is to prevent.

The central processing unit (CPU) 160 supplies power of the optical module 110 and the optical subscriber management unit (PON MAC) 100 to the power supply unit 130 through a power control signal at the request of the optical output monitoring unit 140. Ask to block. In addition, when the optical module 110 and the optical subscriber management unit (PON MAC, 100) is in a normal state, the optical subscriber management unit (PON MAC, 100) serves to transfer control to control the laser diode of the optical module 110. .

The power supply unit 130 switches on / off according to the power control signal determined by the CPU 160 to supply or cut off power to the optical module 110 and the optical subscriber management unit PON MAC 100. .

3 is a diagram illustrating an operation flow of a complex program logic controller according to an exemplary embodiment of the present invention.

As shown in FIG. 3, the optical subscriber management unit (PON MAC) 100 receives a gate signal transmitted from the OLT 10 when the power is initially supplied, initialized, and receives the signal (registration request signal) for requesting registration. The module 110 transmits the data to the OLT 10. The OLT 10 receives the registration request signal transmitted from the optical subscriber management unit (PON MAC) 100 to register the optical subscriber device 20 and grants a logical link identification (LLID) to the optical subscriber device 20. . The OLT 10 transmits a message regarding the registration information and the LLID allocation information of the optical subscriber device 20 to the optical subscriber device 20.

In operation 301, the complex program logic controller CPLD checks whether the optical power management unit PON MAC 100, which is initially powered from the power supply unit 130, is initialized. In step 303, the light output monitoring unit 140 blocks the light output from the optical module 110 through the central processing unit (CPU) 160, and then registers the registration state of the optical subscriber management unit (PON MAC) 100 from the OLT 10. Check and proceed to step 305.

In step 305, the optical power monitoring unit 140 checks the registration status of the optical subscriber management unit (PON MAC) 100 to determine whether it is registered or unregistered in step 303. As a result, the optical subscriber management unit (PON MAC) 100 returns to the registered state. If it is determined that the process proceeds to step 307, if it is determined that the state is not registered proceeds to step 311.

At this time, the optical subscriber management unit (PON MAC, 100) in the registration state in step 307 is determined that the optical module 110 is not normally controlled first through the optical subscriber management unit (PON MAC, 100) to the OLT (10) The optical module 110 requests to transmit an error message, requests the central processing unit (CPU) 160 to cut off power to the optical module 110, and outputs a power control signal to the power supply unit 130. Thereafter, in step 309, the power supply unit 130 switches off the power supply to the optical module 110 according to the power control signal determined by the CPU 160.

In step 311, it is determined that the optical subscriber management unit (PON MAC) 100 is in an unregistered state, and the composite program logic control unit CPLD 120 according to the optical output control signal from the optical subscriber management unit PON MAC 100 is determined to be normally controlled. The light output of the optical module 110 is controlled. If the optical subscriber management unit (PON MAC) 100 receives the deregistration information or the information from the optical module 110 that the optical signal from the OLT 10 is not input, the process returns to step 301 and is initially registered. Or verify the state of the re-registration optical module 110.

On the other hand, in step 315, the optical output monitoring unit 140 is not initialized by the optical subscriber management unit (PON MAC, 100) initially supplied from the power supply unit 130 in step 301 optical subscriber management unit (PON MAC, 100) It is determined that the state is not in a normal state, and requests the central processing unit (CPU) 160 to control to cut off the power of the optical subscriber management unit (PON MAC, 100) supplied through the power supply unit 130.

Accordingly, when an abnormal operation of the optical subscriber management unit (PON MAC) 100 and the optical module 110 occurs in the optical subscriber device 20 of the passive optical subscriber network, malfunctions may be blocked in advance, and other optical subscriber devices in normal operation may be blocked. It can block its impact.

As described above, a Radio Over Fiber system and method for compensating for a transmission time delay according to an embodiment of the present invention can be made. Meanwhile, the above-described description of the present invention has been described in detail. There may be various embodiments without departing from. Therefore, the scope of the present invention should not be defined by the described embodiments, but by the claims and equivalents of the claims.

The present invention made as described above can block the malfunction in advance when abnormal operation occurs in the optical subscriber device of the passive optical subscriber network, and has the effect of blocking the effect on other optical subscriber devices in normal operation.

Claims (14)

In the optical subscriber device of the passive optical subscriber network, A power supply unit supplying power to the optical subscriber device; An optical module for converting and outputting an optical signal having a wavelength uniquely assigned to each optical subscriber; An optical subscriber management unit for exchanging a message for data transmission with the optical termination device according to the optical reception state from the optical module; And And a composite program logic control unit for controlling the power supply of the optical module according to the registration status of the optical subscriber management unit from the optical termination device. The passive optical subscriber network according to claim 1, wherein the complex program logic controller comprises an optical output monitoring unit which checks a registration state of the optical subscriber management unit from the optical termination device and controls the optical output and power of the optical module. Optical subscriber device. The optical subscriber device of a passive optical subscriber network according to claim 2, wherein the optical output monitoring unit outputs a power control signal to a power supply unit to cut off power when the optical subscriber management unit is not initialized. The power output monitoring unit outputs a power control signal to a power supply unit to cut off power to the optical module when the optical subscriber manager is in a registered state while the optical output of the optical module is limited. An optical subscriber device of a passive optical subscriber network. The passive optical subscriber network according to any one of claims 2 to 4, wherein the power supply unit controls the power supply of the optical module and the optical subscriber management unit by switching under the control of the optical output monitoring unit. Optical subscriber device. The optical subscriber device of a passive optical subscriber network according to claim 1, wherein the complex program logic controller checks the initialization of the optical subscriber management unit and controls to cut off the power of the optical module through a power supply unit when it is not initialized. The optical subscriber device of a passive optical subscriber network according to claim 1, wherein the power supply unit cuts off power supply of the optical subscriber management unit by switching under control of the composite program logic controller. The optical fiber of a passive optical subscriber network according to claim 1, wherein the composite program logic controller controls the optical output of the optical module according to the optical output control signal from the optical subscriber management unit when the optical module is in a normal state. Subscriber device. In the optical subscriber device of the passive optical subscriber network, Confirming initialization of an optical subscriber management unit by supplying power to the optical subscriber device; Checking the registration status of the optical subscriber management unit from the optical termination device by controlling the optical output of the optical module when initialized by the optical subscriber management unit; Determining whether to register or not to register by checking the registration status of the optical subscriber management unit; And controlling the power supply of the optical module according to the registered / unregistered state of the optical subscriber management unit. 10. The method of claim 9, wherein the composite program logic control unit comprises the step of checking the initialization of the optical subscriber management unit to control the power supply to cut off the power supply of the optical subscriber management unit when not initialized. Method for controlling optical subscriber device in passive optical subscriber network. 10. The passive optical method of claim 9, wherein the composite program logic control unit outputs a power control signal to a power supply unit to cut off power of the optical module when it is determined that the optical subscriber management unit is in a registered state. Method for controlling optical subscriber device in subscriber network. 12. The optical subscriber device control of a passive optical subscriber network according to claim 11, wherein the power supply unit further comprises the step of switching off the power of the optical module by switching according to a power control signal determined from the complex program logic controller. Way. 10. The passive optical of claim 9, wherein the complex program logic control unit outputs a power control signal to a power supply unit to supply power to the optical module when it is determined that the optical subscriber management unit is in a registered state. Method for controlling optical subscriber device in subscriber network. The optical subscriber device control of a passive optical subscriber network according to claim 13, wherein the power supply unit further comprises supplying power to the optical module by switching according to a power control signal determined from the complex program logic controller. Way.

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