WO2013097468A1

WO2013097468A1 - Optical distribution network fault detection method, device, and system

Info

Publication number: WO2013097468A1
Application number: PCT/CN2012/080320
Authority: WO
Inventors: 赵峻; 肖司淼
Original assignee: 华为技术有限公司
Priority date: 2011-12-27
Filing date: 2012-08-17
Publication date: 2013-07-04
Also published as: WO2013097097A1; CN102725975A; CN102725975B

Abstract

Embodiments of the present invention provide an optical distribution network fault detection method, device, and system. The method mainly comprises: disposing at least one first identifier on each fiber before a final splitter of an optical distribution network, the first identifiers using different wavelengths, and disposing at least one second identifier on each fiber after the final splitter, the second identifiers using a same wavelength; sending an optical signal to the optical distribution network, the optical signal being an optical signal for testing; receiving an optical signal returned by each identifier in the optical distribution network; according to the returned optical signal, detecting whether the fiber at each identifier is faulty. By means of the embodiments of the present invention, without depending on information reported by a terminal device, rapid and accurate fault location can be performed before accessing of the terminal device on a fiber already laid.

Description

Method, device and system for fault detection of optical distribution network

Technical field

The present invention relates to the field of wireless communication technologies, and in particular, to a method, an apparatus, and a system for performing fault detection on an optical distribution network.

Background of the invention

Optical communication has the advantages of large transmission capacity and high transmission quality, and has been widely used. At present, with the increasing demand for communication capacity on the user side, the optical access network, which is an important part of the optical communication network, has developed extremely rapidly. Due to the complex deployment and use environment of the fiber-to-the-home system, and the central office OLT (Optical) Line terminal, optical line unit, and ONU (Optical network unit)/ONT (Optical network) Terminal, optical network terminal) is a pure passive optical path connection, which makes the diagnosis of line faults extremely difficult.

Typical optical access network access methods include: P2P (Point to Point) access and P2MP (Point) To multi-point, point-to-multipoint) PON access.

For a P2MP PON network, since the end branch fibers are connected in parallel, it is not possible to use a conventional OTDR only at the central office (Optical time). Domain reflectormeter, optical time domain reflectometer) detects the reflected signal and detects faults on different branches.

A method for detecting faults in optical distribution in a P2MP PON network in the prior art is: performing fault detection based on status information reported by the terminal device. In the method, the PON port is determined by detecting the device power-off message reported by the offline access terminal device and the online state of the remaining access terminal devices under the same central access device port as the offline access terminal device. Whether the offline access terminal device or the optical fiber transmission line connected to the offline access terminal device fails.

A disadvantage of the method for detecting faults in optical distribution in a PON network of a P2MP in the prior art is that, depending on the information reported by the terminal device, it is impossible to identify and troubleshoot the network that has been laid before the terminal device accesses.

Summary of the invention

The present invention provides a method, device and system for fault detection of an optical distribution network, so as to achieve fast and accurate fault location of the laid fiber before the terminal device is accessed.

An aspect of the present invention provides a method for detecting a fault in an optical distribution network, the optical distribution network comprising: a trunk fiber, a branch fiber, and a splitter, wherein the trunk fiber passes through each of the splitters and the respective Branch fiber connection, at least one first identifier is respectively disposed on each fiber before the last stage splitter of the optical distribution network, the first identifier adopts different wavelengths, and each fiber after the last stage splitter At least one second identifier is respectively disposed on the second identifier, and the second identifier uses the same wavelength, and the method includes:

Transmitting an optical signal to the optical distribution network, wherein the optical signal is an optical signal for testing;

Receiving an optical signal returned by each identifier in the optical distribution network;

And detecting, according to the returned optical signal, whether the optical fiber in which each identifier is located is faulty.

Another aspect of the present invention provides an apparatus for detecting a fault in an optical distribution network, the apparatus for detecting faults comprising: an identification unit for respectively respectively on each of the optical fibers before the final splitter of the optical distribution network Providing at least one first identifier, the first identifier adopting different wavelengths, and at least one second identifier is respectively disposed on each of the optical fibers after the final splitter, the second identifier adopting the same wavelength; a signal sending unit, configured to send an optical signal to the optical distribution network, wherein the optical signal is an optical signal for testing;

An optical signal receiving unit, configured to receive an optical signal returned by each identifier in the optical distribution network;

The detecting unit detects, according to the returned optical signal, whether the optical fiber in which each identifier is located is faulty.

The present invention also provides an optical network system, the optical network system includes: an OLT, an optical distribution network, and an ONU, where the OLT is connected to the ONU through an optical distribution network, where the optical distribution network includes: a backbone optical fiber, a branch An optical fiber and a splitter, wherein the trunk optical fiber is connected to the branch fiber through the splitter, the optical network system further includes: a fault detecting device, where the fault detecting unit includes:

An identifier unit, configured to respectively set at least one first identifier on each of the optical fibers before the last-stage splitter of the optical distribution network, where the first identifier adopts different wavelengths, and each of the subsequent stages At least one second identifier is disposed on the optical fiber, the second identifier adopts the same wavelength; the optical signal sending unit is configured to send an optical signal to the optical distribution network, wherein the optical signal is an optical signal for testing ;

The detecting unit detects, according to the returned optical signal, whether the optical fiber in which each identifier is located is faulty. Another aspect of the present invention provides an optical distribution network, the optical distribution network comprising: a trunk fiber, a branch fiber, and a splitter, wherein the trunk fiber is connected to the branch fibers through an associated splitter, The optical distribution network further includes: a device for detecting a fault, the fault detecting device comprising:

It can be seen from the above technical solution provided by the present invention that at least one first identifier is respectively disposed on each optical fiber before the last-stage splitter of the optical distribution network, and the first identifier Using different wavelengths, at least one second identifier is disposed on each of the fibers behind the final stage splitter, and the second identifier uses the same wavelength to transmit an optical signal to the optical distribution network to receive the optical distribution. The optical signal returned by each identifier in the network detects whether the optical fiber of each identifier is faulty according to the returned optical signal, and realizes that the information is not reported by the terminal device, and the terminal device accesses the Lay the fiber for fast and accurate fault location.

BRIEF DESCRIPTION OF THE DRAWINGS

1 is a flowchart of a method for performing fault detection on an optical distribution network according to an embodiment of the present invention;

2 is a specific structural diagram of an optical network system for detecting a fault in an optical distribution network according to Embodiment 1 of the present invention;

FIG. 3 is a schematic structural diagram of an apparatus for detecting a fault in an optical distribution network according to Embodiment 1 of the present invention.

Mode for carrying out the invention

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Embodiment 1

This embodiment provides a method for performing fault detection on an optical distribution network as shown in FIG. 1.

The passive optical network system includes: an OLT, an optical distribution network (Optical Distribution Network, And the ONU, the OLT is connected to the ONU by using the ODN, the ODN includes: a trunk fiber, a branch fiber, and a splitter, where the trunk fiber and the branch fiber are connected by a splitter, in the ODN At least one first identifier is disposed on each of the optical fibers before the final splitter, the first identifier adopts different wavelengths, and at least one second identifier is respectively disposed on each of the fibers behind the final splitter. The second identifier adopts the same wavelength, and the method includes:

Step 11. The fault detecting device sends an optical signal to the ODN, wherein the optical signal is an optical signal for testing.

The fault detecting device is located on the OLT side and is connected to the trunk fiber of the ODN through a wavelength division multiplexer.

Step 12: The fault detecting device receives the optical signal returned by each identifier in the ODN.

The wavelength adopted by the first identifier and the wavelength used by the second identifier are respectively selected from a wavelength pool, and the wavelength ranges are different, that is, each of the optical fibers disposed before the final optical splitter The wavelengths of the first identifiers are different. The second identifiers disposed on the branch fibers after the final beam splitter use the same wavelength, but the wavelengths used by the first identifiers are different, mainly for Clearly and quickly locate the failed fiber.

Step 13: The fault detecting device detects, according to the optical signal returned by each identifier, whether the optical fiber where each identifier is located is faulty.

Further, the detecting, by the fault detecting device, whether the optical fiber in which the optical identifiers are located is faulty according to the optical signals returned by the identifiers includes:

When the fiber before the last-stage splitter fails, the fault detecting device determines the branch fiber that is faulty according to the wavelength adopted by each identifier; when the fiber behind the last-stage splitter fails, according to the The time of the optical signal returned by each identifier determines the branch fiber that has failed.

Specifically, in the embodiment of the present invention, various wavelengths are aggregated into a wavelength pool, and respective wavelengths are respectively selected from the wavelength pool and allocated to the first identifier, the second identifier, and the third identifier, wherein the first An identifier is disposed on each of the optical fibers before the final splitter, and in order to accurately locate the fault of each optical fiber before the final splitter, between the first identifiers disposed before the final splitter Different wavelengths are used to select different wavelengths from the wavelength pool to identify the first identifier, that is, the faulty fiber in front of the last-stage splitter, and the wavelengths adopted by the first identifiers are different, and the wavelength division method is used. Quickly and accurately locate the faulty fiber; each fiber behind the final stage splitter is provided with a second identifier on each of the fibers, and the second identifier is generally used because there are more fibers behind the final splitter. The fault of each branch fiber is located by means of time division multiplexing. Wherein the second identifier can select the same wavelength in the wavelength pool to identify the second identifier, wherein the number of branch fibers after the final splitter is mainly considered, if the final splitter is The amount of branch fiber data is not large. You can consider using the first identifier on the branch fiber, and locate the faulty fiber through the different wavelengths of the first identifier. Generally, there are many branch fibers behind the final stage splitter. The same wavelength can be selected from the wavelength pool as the wavelength of the second identifier, which is used to identify each branch fiber (the same wavelength is used for the second identifier). It means that a plurality of second identifiers are identified by the same wavelength, but the wavelength between the second identifier and the first identifier is different, and the faulty branch fiber is distinguished by time division multiplexing.

Further, a third identifier is disposed on each of the splitters in the ODN, and the any one of the third identifiers is in one-to-one correspondence with the branches of the splitters, and the method further includes:

The fault detecting device determines the faulty splitter according to the third identifier of each of the splitters.

Specifically, the splitters (SPLs) of the different branch ratios in the ODN, that is, the SPLs of the different branch ratios respectively correspond to different wavelengths, and select appropriate wavelengths from the wavelength pool to perform SPL according to the wavelengths corresponding to the respective SPLs. Type identifier. When the splitter fails, the faulty splitter can be distinguished from the third identifier to determine that the fault occurs within the splitting range of the first stage splitter.

The first identifier, the second identifier, and the third identifier may be a band rejection filter, and the band rejection filter may be a fiber Bragg grating (Fiber Bragg) Grating, FBG).

The method for specifically identifying the fault is as follows: the first identifier and the second identifier are respectively packaged in the connector of the optical fiber, and each of the optical fibers is respectively provided with at least one first identifier or a second identifier. Generally, because the length of the optical fiber before the non-last-stage optical splitter is long, the same first identifier (the first identifier with the same wavelength) can be used on the same optical fiber, and the same first identifier is placed on the optical fiber. In different positions, the faults in different positions of the fiber can be fault-located in a time-division manner. The fibers in the preceding segments of the last-stage splitter are fault-located by means of wavelength division due to the different wavelengths of the first markers. When the fault detecting device uses a tunable light source for wavelength scanning or a wide-spectrum light source for tunable reception, when performing wavelength scanning, detecting a reflection peak of an optical signal returned by each identifier, when an optical fiber fails, the optical fiber is on the optical fiber. The reflected peak corresponding to the optical signal returned by each marker will be weakened or disappeared to determine the specifically faulty fiber. For example, for the optical fiber before the final optical splitter, the fault detecting device has different reflection peaks of the returned optical signals scanned according to different wavelengths, so that the faulty optical fiber can be quickly and accurately located. Further, if a plurality of first identifiers are disposed on a certain optical fiber before the final optical splitter, the time of the optical signal returned by each first identifier is different, and the center wavelength of the reflected optical signal is the same, and the time division method is adopted. The distance difference is calculated, and according to the specific position of the first identifier, the specific fiber is faulty. For the branch fiber after the final beam splitter, the position of each second marker is calculated according to the time difference of the optical signals returned by the second optical marker on each branch fiber in a time division manner, and the fault is performed. Positioning, for example, since the actual laid final fiber has a difference in deployment distance of >0.4 m, the faulty branch fiber is determined according to the actual distance difference of each branch fiber after the last stage SPL.

Further, the method may further include: setting a predetermined threshold of the return optical signal in advance, and performing the determination of the fault detection when the fault detecting device determines that the strength of the returned optical signal is less than a predetermined threshold.

In the embodiment of the present invention, at least one first identifier is respectively disposed on each optical fiber before the final stage splitter of the ODN, and the first identifier adopts different wavelengths, and each optical fiber after the final splitter is used. Separating at least one second identifier, wherein the second identifier uses the same wavelength to transmit an optical signal to the ODN, and the fault detecting device receives the optical signal returned by each identifier in the ODN, according to the returned The optical signal detects whether the optical fiber of each identifier is faulty, and implements fast fault location for the laid optical fiber before the terminal device accesses without relying on the information reported by the terminal device.

An identifier unit, configured to respectively set at least one first identifier on each fiber before the last stage splitter of the ODN, the first identifier adopting different wavelengths, and each fiber behind the last stage splitter Separating at least one second identifier, the second identifier adopting the same wavelength; the optical signal sending unit is configured to send an optical signal to the ODN, wherein the optical signal is an optical signal for testing;

An optical signal receiving unit, configured to receive an optical signal returned by each identifier in the ODN;

Another embodiment of the present invention provides an optical network system for detecting an ODN, and the specific structure of the optical network system is as shown in FIG. 2 .

The optical network system of FIG. 2 includes: an OLT, an ODN, and at least one ONU, wherein the OLT is connected to each ONU through an ODN; the ODN includes: a trunk fiber, at least one splitter (SPL), and a branch fiber, The backbone fiber is connected to each branch fiber through each splitter.

The optical network system further includes: a fault detecting device (also referred to as an analyzer Analyzer) located on the OLT side and passing through a wavelength division multiplexer (Wavelength) Division Multiplexer, WDM) is connected to the backbone fiber.

As shown in FIG. 2, the final stage splitter includes: SPL2 and SPL3, and the final stage splitters SPL2 and SPL3 further include a splitter SPL1 and a trunk fiber and a branch fiber, respectively, which are respectively disposed on the trunk fiber and the branch fiber. The at least one first identifier is used to identify each of the first identifiers by selecting a suitable wavelength in the wavelength pool, so that the first identifiers use different wavelengths, thereby identifying the faulty fiber by a wavelength division method. Further, the SPL1, the SPL2, and the SPL3 are respectively identified by using different wavelengths to identify which splitting range of the splitter belongs to the split optical fiber. At least one second identifier is disposed on each branch fiber after the final splitter, and a suitable wavelength is selected in the wavelength pool to identify each of the second identifiers, specifically, wavelengths are used on each branch fiber. The same second identifier distinguishes the faulty fiber by the time division manner, that is, the difference in the placement position between the branch fibers of the second identifiers.

details as follows:

The threshold of the returned optical signal is set in advance, the optical signal for testing is transmitted to the ODN, and the optical signal returned by the optical identifier through each optical marker is received. The predetermined threshold is the intensity magnitude returned by the normal optical signal. When the fault detecting device periodically scans, the intensity amplitude (ie, the reflection peak) of the returned optical signal is within a threshold of the preset optical signal, but the intensity of the returned optical signal is normal. The intensity of the optical signal is small, and it can be judged that the returned optical signal is returned from a certain fiber that has failed.

When the fiber before the last-stage splitter fails, determining the faulty branch fiber according to the wavelength adopted by each identifier; when the fiber behind the last-stage splitter fails, according to the The time of the optical signal returned by the marker to determine the branch fiber that failed.

The first identifier, the second identifier, and the third identifier are band rejection filters, and the band rejection filter may be a fiber Bragg grating (Fiber) Bragg gratings, FBGs, can also be other types of devices that can be packaged in fiber optic connectors or in other packages.

Since the length of the optical fiber before the last SPL is long, a plurality of first optical markers can be set on the same optical fiber according to a set distance interval (for example, 2 km), and the wavelengths of the first optical identifiers are the same. Each optical fiber before the grading splitter uses a different optical identifier for identifying the faulty optical fiber. For the same optical fiber, the first optical identifier of the same wavelength is used to identify different positions of the optical fiber, and the first optical identifier is set on each optical fiber. The position of the device, that is, the time at which the optical signal of the test passes through the optical signal returned by the first optical marker, is different, and it is detected which segment of the optical fiber the faulty fiber is located.

Since the length of the branch fiber between the final SPL and the ONU is short, the branch fiber may optionally be mounted with a second identifier, and the second identifier disposed on the branch fiber has the same wavelength. When the passive optical network system is actually deployed, the distance between the placement positions of the ONUs is greater than the statistical value of 0.4 m, and the optical signals reflected by the second identifiers on the respective branch fibers of the same final SPL are returned. The wavelengths are the same, but the reception time to the OLT-side failure detecting device is different, and the defective optical fiber after the last-stage SPL is detected by time division.

In the embodiment of the present invention, at least one first identifier is respectively disposed on each optical fiber before the final stage splitter of the ODN, and the first identifier adopts different wavelengths, and each optical fiber after the final splitter is used. Providing at least one second identifier, the second identifier adopting the same wavelength, transmitting an optical signal to the ODN, and receiving an optical signal returned by each identifier in the ODN, according to the returned optical signal, The device detects whether the optical fiber of each identifier is faulty, and implements fast fault location for the laid fiber before the terminal device accesses, without relying on the information reported by the terminal device.

The embodiment of the present invention further provides a device for detecting faults of an ODN. As shown in FIG. 3, the ODN includes: a trunk fiber, a branch fiber, and a splitter. The trunk fiber and the branch fiber are connected by a splitter. The device for detecting faults includes:

The identification unit 300 is configured to respectively set at least one first identifier on each optical fiber before the last-stage splitter of the ODN, the first identifier adopts different wavelengths, and each optical fiber after the last-stage splitter Providing at least one second identifier on the second, the second identifier adopting the same wavelength;

The optical signal sending unit 301 is configured to send an optical signal to the ODN, where the optical signal is an optical signal for testing;

The optical signal receiving unit 302 is configured to receive an optical signal returned by each identifier in the ODN.

The detecting unit 303 detects, according to the optical signal returned by each identifier, whether the optical fiber in which each identifier is located is faulty.

Further, the detecting unit 303 is specifically configured to: when the optical fiber before the last-stage splitter fails, determine a faulty branch fiber according to different wavelengths adopted by each identifier; when the final-stage branch If the fiber behind the device fails, the branch fiber that has failed is determined according to the time of the optical signal returned by each identifier.

The identifier unit 300 is further configured to respectively set a third identifier on each of the splitters in the ODN, and the any one of the third identifiers has a one-to-one correspondence with the branches of the splitters;

The detecting unit 303 is further configured to determine, according to the third identifier of each splitter, a faulty splitter.

The first identifier, the second identifier, and the third identifier are band rejection filters.

The embodiment of the present invention further provides an ODN, where the ODN includes: a trunk fiber, a branch fiber, and a splitter, where the trunk fiber is connected to the branch fiber through an associated splitter, and the ODN further includes: The device for detecting, the fault detecting device comprising:

An identifier unit, configured to respectively set at least one first identifier on each of the optical fibers before the last-stage splitter of the optical distribution network, where the first identifier adopts different wavelengths, and each of the subsequent stages At least one second identifier is disposed on the optical fiber, and the second identifier uses the same wavelength; the optical signal sending unit is configured to send an optical signal to the ODN, wherein the optical signal is an optical signal for testing;

The detecting unit detects whether the optical fiber in which each identifier is located is faulty according to the optical signal returned by each identifier.

The detecting unit is specifically configured to: when the optical fiber before the last-stage splitter fails, determine the faulty branch fiber according to different wavelengths adopted by each identifier; when the fiber behind the last-stage splitter If a fault occurs, the faulty branch fiber is determined according to the time of the optical signal returned by each identifier.

Through the description of the foregoing embodiments, those skilled in the art can clearly understand that the specific processing procedure for fault detection of the ODN proposed by the embodiment of the present invention may be implemented by hardware, or may be added by software to the necessary general hardware platform. In order to realize the understanding based on the understanding, the technical solution of the present invention can be embodied in the form of a software product, which can be stored in a computer readable storage medium (which may be a CD-ROM, a USB flash drive, a mobile hard disk, etc.). A number of instructions are included to cause a computer device (which may be a personal computer, server, or network device, etc.) to perform the methods described in various embodiments of the present invention.

The above is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or within the technical scope disclosed by the present invention. Alternatives are intended to be covered by the scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

A method for detecting a fault in an optical distribution network, the optical distribution network comprising: a trunk optical fiber, a branch optical fiber, and a splitter, wherein the trunk optical fiber is connected to the branch optical fibers through an associated splitter, wherein Providing at least one first identifier on each of the optical fibers before the last-stage splitter of the optical distribution network, the first identifiers adopting different wavelengths, and at least each optical fiber after the final-stage splitter is respectively disposed at least a second identifier, the second identifier adopts the same wavelength, and the method includes:

Transmitting an optical signal to the optical distribution network, wherein the optical signal is an optical signal for testing;

Receiving an optical signal returned by each identifier in the optical distribution network;

And detecting, according to the returned optical signal, whether the optical fiber in which each identifier is located is faulty.
The method according to claim 1, wherein the detecting, according to the returned optical signal, whether the optical fiber in which the optical identifiers are located is faulty comprises:

When the fiber before the last-stage splitter fails, determining the faulty branch fiber according to the wavelength adopted by each identifier; when the fiber behind the last-stage splitter fails, according to the The time of the optical signal returned by the marker to determine the branch fiber that failed.
The method according to claim 1, wherein a third identifier is disposed on each of the splitters in the optical distribution network, and the any one of the third identifiers and the branches of the splitters Corresponding to one-to-one, the method further includes:

A faulty splitter is determined based on the third identifier of each of the splitters.
The method of claims 1-3, wherein the first identifier, the second identifier, and the third identifier are band stop filters.
A device for detecting faults in an optical distribution network, configured to perform fault detection on an optical distribution network, where the optical distribution network includes: a trunk fiber, a branch fiber, and a splitter, and the trunk fiber and the branch fiber pass through the branch The device is characterized in that: the device for detecting faults comprises:

An identifier unit, configured to respectively set at least one first identifier on each of the optical fibers before the last-stage splitter of the optical distribution network, where the first identifier adopts different wavelengths, and each of the subsequent stages Having at least one second identifier on the optical fiber, the second identifier adopting the same wavelength;

An optical signal sending unit, configured to send an optical signal to the optical distribution network, wherein the optical signal is an optical signal for testing;

An optical signal receiving unit, configured to receive an optical signal returned by each identifier in the optical distribution network;

The detecting unit detects, according to the returned optical signal, whether the optical fiber in which each identifier is located is faulty.
The apparatus for detecting faults according to claim 5, wherein the detecting unit is specifically configured to: when the optical fiber before the last-stage splitter fails, determine the occurrence according to different wavelengths adopted by each identifier The faulty branch fiber; when the fiber behind the last stage splitter fails, the faulty branch fiber is determined according to the time of the optical signal returned by each identifier.
The apparatus for detecting faults according to claim 5, wherein the identification unit is further configured to respectively set a third identifier, each of the third identifiers, on each of the splitters in the optical distribution network. And one-to-one correspondence with the branches of the splitters;

The detecting unit is further configured to determine a faulty splitter according to the third identifier of each of the splitters.
The apparatus for detecting faults according to any of claims 5-7, wherein the first identifier, the second identifier, and the third identifier are band rejection filters.
An optical network system, comprising: an optical line terminal, an optical distribution network, and an optical network unit, wherein the optical line terminal is connected to the optical network unit through an optical distribution network, where the optical distribution network includes: a backbone An optical fiber, a branch fiber, and a splitter, wherein the trunk fiber is connected to the branch fiber through a splitter, wherein the optical network system further includes: a fault detecting device, wherein the fault detecting device is located in the light On the line terminal side, the fault detecting device includes:

An identifier unit, configured to respectively set at least one first identifier on each of the optical fibers before the last-stage splitter of the optical distribution network, where the first identifier adopts different wavelengths, and each of the subsequent stages Having at least one second identifier on the optical fiber, the second identifier adopting the same wavelength;

An optical signal sending unit, configured to send an optical signal to the optical distribution network, wherein the optical signal is an optical signal for testing;

An optical signal receiving unit, configured to receive an optical signal returned by each identifier in the optical distribution network;

The detecting unit detects, according to the returned optical signal, whether the optical fiber in which each identifier is located is faulty.
The optical network system according to claim 9, wherein the detecting unit is specifically configured to: when the optical fiber before the last-stage splitter fails, determine a fault according to different wavelengths adopted by each identifier. Branch fiber; when the fiber behind the last-stage splitter fails, the faulty branch fiber is determined according to the time of the optical signal returned by each identifier.
The optical network system according to claim 9, wherein the identification unit is further configured to respectively set a third identifier, each of the third identifiers, on each of the splitters in the optical distribution network. Corresponding to the branch ratio of each of the splitters;

The detecting unit is further configured to determine a faulty splitter according to the third identifier of each of the splitters.
An optical distribution network, the optical distribution network comprising: a trunk fiber, a branch fiber, and a splitter, wherein the trunk fiber is connected to the branch fibers through a sub-distributor, wherein the optical distribution network further The method includes: a fault detecting device, where the fault detecting device includes:

An identifier unit, configured to respectively set at least one first identifier on each of the optical fibers before the last-stage splitter of the optical distribution network, where the first identifier adopts different wavelengths, and each of the subsequent stages At least one second identifier is disposed on the optical fiber, the second identifier adopts the same wavelength; the optical signal sending unit is configured to send an optical signal to the optical distribution network, wherein the optical signal is an optical signal for testing ;

An optical signal receiving unit, configured to receive an optical signal returned by each identifier in the optical distribution network;

The detecting unit detects, according to the returned optical signal, whether the optical fiber in which each identifier is located is faulty.
The optical distribution network according to claim 12, wherein the detecting unit is specifically configured to: when the optical fiber before the last-stage splitter fails, determine that the fault occurs according to different wavelengths adopted by each identifier Branch fiber; when the fiber behind the last-stage splitter fails, the faulty branch fiber is determined according to the time of the optical signal returned by each identifier.