200841640 螓 九、發明說明： 【發明所屬之技術領域】 本發明係有關被動式光纖網路（Passive 〇ptical Network，PON)監測技術，特別是關於在被動式光纖網路 上利用分時多工（Time Division Multiplexing，TDM)技 術使各光纖網路單元（Optical Network Unit，0NU)依序 回應以監測光纖鏈路品質的方法。 • 【先前技術】 _ 由於容量大、可靠性高、傳輸距離長等特性，光纖逐 漸成為電信鏈路中的骨幹。透過光纖將資料直接傳送到用 戶端的服務將是未來寬頻鏈路應用的主流，例如，光纖到 交換箱（Fiber To The Cabinet; FTTCab)、光纖到路邊 (Fiber To The Curb; FTTC)、光纖到樓（Fiber To The Building; FTTB)及光纖到家（Fiber To The Home; FTTH)， 上述服務可統稱為FTTx。被動式光纖網路（Passive Optical Network，PO0基於無源之光纖架構，係一種極具 競爭優勢之鏈結技術。第一圖顯示一傳統之被動式光纖網 路100之系統架構示意圖，其中光纖線路終端設備 110(0ptical Line Terminator，0LT)對外連接至光纖鏈路 主幹，由光纖線路終端設備下傳之光訊號，透過光纖經由 被動元件光分歧器（Splitter，SP>120，將光訊號分路廣播 至各終端用戶，亦即光纖網路單元（Optical Network Unit， 5 200841640 * * .〇·)131-134。而光纖網路單元131_134上傳之信號則經光 、 分歧器120耦合後傳送給光纖線路終端設備110。 隨著光纖網路應用普及化，光纖鏈路之故障判斷亦愈 發重要。參照第二圖，其顯示光纖網路1〇〇之斷線狀況示 意圖。假設光分歧器120至光纖網路單元134間之光纖鏈 路斷線，維修人員接獲客戶反應後，無法立刻判斷此故障 為光纖線路終端器U0至光分歧器120間斷線，或是光分 #歧器I20至光纖網路單70 134間斷線。此外，架設在外之 光纖纜線亦可能受到外力作用而導致傳輸品質劣化，如工 程施工時不慎擠壓、碰撞，<甚至是受到重力影響而彎曲 等。此-劣化過程緩慢，往往不易立刻察覺，但累積形成 故障狀況後將引發使用者不便，影響商譽。此等故障事件 傳統上可以使用諸如光時域反射器—㈣tiffie_dQmain reflWtxr;喔）之光鏈路輯點檢測裝置來做故障 •點之定位。光時域反射器藉由不同時間點相對於光纖測試 信號自然反射而回的光功率和先前記錄之原始光纖品質執 跡之比對而判斷故障典或斷線點所在之處。然光時域反射 器並無法有效判讀如第-圖和第二圖所示之樹狀被動式光 纖網路之狀態，因其難㈣職生於缝網㈣構末端之 基於以上傳統技術之缺點 其有必要提出—種光纖鏈 6 200841640 路監測方法和系統以補光時域反射器等習用技術之不足。 於平時可以監測紀錄光纖傳輸品質，以便及時更換已劣化 售 之光纖纜線，遇突發之光纖纜線斷線時，又可以即時判斷 • 故障線段，縮短檢修時間。 【發明内容】 - 本發明之一目的在於提出一種被動式光纖網路之光纖 - 鏈路監測方法，可即時判斷光纖鏈路斷線位置，縮短維修 時間。 本發明之另一目的在於提出一種被動式光纖網路之光 纖鏈路監測方法，以偵測紀錄光纖鏈路品質，及早更換劣 化之光纖纟覽線。 本發明之又一目的在於提出一種實現上述被動式光纖 網路之光纖鏈路監測方法之裝置。 依據上述目的，本發明提出一種光纖鏈路監測系統， 其包含一主控監測裝置以及複數回應裝置，其中之主控監 測裝置廣播一特定指令至上述複數回應裝置以要求複數回 應裝置中之一特定回應裝置持續回傳一第一特定時間長度 之一特定回應光訊號，且主控監測裝置依據特定回應光訊 號接收之狀況，判斷連接至特定回應裝置之一特定光纖鏈 路是否正常。 7 200841640 本發明亦提出一種光纖鏈路監測方法，其包含以下步 毳 驟：自一主控監測裝置廣播一特定指令至複數回應裝置以 - 要求複數回應裝置中之一特定回應裝置持續回傳一第一特 定時間長度之一特定回應光訊號；自特定回應裝置回傳特 定回應光訊號至主控監測裝置；以及依據特定回應光訊號 接收之狀況，判斷連接至特定回應裝置之特定光纖鏈路是 ‘ 否正常。 ⑩ 【實施方式】 本發明一些實施例的詳細描述如下，然而，除了該詳 細描述外，本發明還可以廣泛地在其他的實施例施行。亦 即，本發明的範圍不受已提出之實施例的限制，而應以本 發明提出之申請專利範圍為準。 再者，為提供更清楚的描述及更易理解本發明，圖示 内各部份並沒有依照其相對尺寸繪圖，某些尺寸與其他相 關尺度相比已經被誇張；不相關之細節部份也未完全繪 出’以求圖不之簡潔。 第三圖顯示本發明一實施例之具有光纖鏈路監測功能 之光纖網路系統300之架構示意圖，其包含光纖線路終端 設備310、主控監測裝置340、光分歧器320、回應裝置 350. 1-35CK 4(以下或統稱為回應裝置350)及光纖網路單元 8 200841640 • 犯0·1—330·4。與第一圖之傳統光纖網路系統100比較可 . 知，其中之主控監測裝置340和回應裝置350係本發明新 加入用以執行監測功能之主要裝置。光纖線路終端設備310 ' 連接至主控監測裝置340，主控監測裝置340經由主要光 纖鏈路360連接至光分歧器32〇。光分歧器320分別透過 光纖鍵路361-364連接至回應裝置350. 1-350.4。回應裝 置350· 1-350.4分別連接至各光纖網路單元33〇.卜330· 4。 • 本實施例中，主控監測裝置340以分時多工（Time Division Multiplexing, TDM )技術廣播波長為 850nm(narometer;奈米）的光訊號以命令各回應裝置持續 發出回應之光訊號一特定長度之時間，例如2秒鐘。光分 歧器320將此廣播之光訊號分別轉送到各個回應裝置 350· 1-350.4。需注意的是，85〇11111僅為舉例，此廣播光訊 號並不限定特定波長，其僅須避開既有通信光訊號使用之 _波長即可。持續發光2秒鐘亦非用以限定，該特定長度之 時間只要足以量測回應光功率即可。回應裝置350. 1 -350· 4 在接收到發光命令後，回傳波長780腿之光訊號至主控監 測裝置340。此回傳波長亦僅為舉例，其僅須避開既有傳 輸通彳§波長即可。主控監測裝置340在收到回傳的光信號 後，可分析並紀錄光功率，據以判定連接至回應裝置 350· 1-350.4之光纖鏈路330· 1-330.4是否正常。例如， 200841640 未收到回傳的光信號、回傳的光信號功率過低（小於一特定 .門檻值）或過高（大於另一特定門檻值），則可判斷連接至回 • 應裝置350·卜350· 4之光纖鏈路330· 330· 4可能發生異 - 常。此外，基於所有回傳光信號之狀況，可以綜合研判故 障之位置是否位於主控監測裝置340和光分歧器32〇間之 主要光纖鏈路360。 第四圖顯示依據本發明一實施例之主控監測裝置34〇 • 之功能方塊圖，其包含光波長耦合器340c、光功率檢測單 元340d、中央處理單元34〇a和雷射光源34〇b。光波長輕 合器340c連接至外部之光纖線路終端譟備31〇(未顯示於 圖中）和主要光纖鏈路360(未顯示於圖中）。光波長轉合器 340c亦連接至雷射光源34〇b和光功率檢測單元34〇d。雷 射光源340b和光功率檢測單元340d均連接至中央處理單 元 340a 〇 中央處理單元340a要求雷射光源340b傳送一波長為 850nm之光訊號搭载一特定指令以命令一特定回應裝置（例 如，回應裝置350.1)回應一光訊號。該85〇nm之光訊號經 由光波長耦合器340c和連接之光纖鏈路向外廣播。在收到 來自該特定回應裝置回傳之780mn波長之光訊號時，經由 光波長耦合器340c傳送至光功率檢測單元34〇d。中央處 理單元340a對光功率檢测單元34〇d量測之結果依據前述 200841640 .之方法進行分析。若結果正常，則中央處理單元3術將啟 、動下-個回應裝置的測試程序；若結果異常，則中央處理 早兀馳判斷此異常狀況是斷線、線路劣化或其它情形， 亚啟動相關告警或處理程序。此中央處理單元可包含記憶 裝置’以記錄歷來光功率測量結果，可供判斷線路品質劣 化情形。 • 帛五圖,4不依據本發明—實施例之回應裝置之功 月b方塊®其包3光波餘合器咖€、光功率檢測單元 3’巾央處理早凡35〇a和雷射光源此。光波長柄合 器、驗連接至外部之光_路單元（未顯示㈣中）和光 纖鍵路（未顯示於圖中）。光波長輕合器驗亦連接至雷射 光源350b和光功率檢測單元35〇d。雷射光源·b和光功 率檢測單元350d均連接至中央處理單元施。來自主控 監職置之85Gnm波長光訊號經由光波長耦合器35〇c傳送 至光功率檢測350d，並由中央處理單元35〇a解析出其中 之特定指令。中央處理單元350a若發現該特定指令之目標 係本回應裝置700，則要求雷射光源35〇1)持續送出一波長 為780nm光訊號’經由光波長耦合器35〇(：和光纖鏈路回傳。 第六圖顯示依據本發明一實施例之光纖鏈路監測方法 之流程圖，其包含步驟601至步驟607。在步驟601中， 光纖線路終端設備端之主控監測裝置將一特定指令廣播至 11 200841640 > 各個光纖網路單元端之回應裝置。在此實施例中係以一波 • 長為850nm之光訊號搭載此特定指令，且命令一特定回應 裝置回應一光訊號持續2耖。在步驟602中，所有回應裝 置均接收到此特定指令。步驟6〇3中，上述特定指令中指 之#寸定回應裝置依要求以波長780nm之光訊號回傳持續 - 秒鐘。在步驟6〇4中，主控監測裝置於此時間内分析來 、 忒特定回應裝置回傳之光訊號，如信號的有無及功率之 專色園楚 、寺。在步驟605中，系統將針對分析結果進一步判斷 “纖鏈路有無劣化或斷線情形，若檢驗回傳之光信號均正 常， ’ 則系統將直接執行步驟607，啟動下一個回應裝置的 :4¾序。但若出現異常狀況，如接收之光功率數值低於 弋‘準值以下’代表鏈路可能有劣化狀況；或完全沒有 光輪入， - ’則表示可能有斷線情形發生故障；此等異常狀況 鲁介吏系统啟動步驟606之告警機制，此機制可透過一人機 常么出視訊或音訊形式之告警信號，以提醒管理者有異 孽收况發生。同時系統亦執行步驟β〇7，啟動下一個回應 二，的偵測程序，藉由後續的回應裝置回傳的光信號以判 义欠障之光纖位置。 圖，^圖例不第二圖之光纖網路系統_斷線狀況示意 35〇 託卜364 *別表示光分歧器、320至回應裝置 • 35〇·4之間的光纖鏈路，斷線狀況發生於光分歧器 12 200841640 320與回應裝置350· 4之間的光纖鏈路364。依據本菸明之 方法，主控監測袭置34〇在執行回應裝置35〇1、3如月 350.3的偵測程序時，均能順利接收來自35〇1、 的〇· 2及 350.3回傳的光訊號，表示光纖線路終端設備3丨〇至一八 歧器320間，及光分歧器32〇至回應裝置35〇 光刀 的0· 2及 350.3間線路正常。主控監測裝置34〇在執行回應壯 350.4的_程序時發現異常狀況，表示光纖線 備310至光分歧器320間或光分歧器3 、、、；端设 衣置35〇 4 之間線路故障；但可由350. 1、350· 2及350· 3的偵负 判辦光纖線路終端設備310至光分歧器32〇間段綠、 . ’ 又綠略為正 苇狀況，故斷線狀沉應當發生於光分歧哭3 " υ复回應萝詈 350.4之間。維修人員可稽帶相關器材迅速到場檢衣# 省時間。 取多，節 上述光訊號之諸如850nm和挪⑽之特定波長和轉 續之特定時間長度均係為了方便說明之舉例，習於斯㈣ 之人士當能賴衫其他可替代之數_紐成本發明之 功能和特色。各實施例僅係可能之實作範例，許多變異或 修改均可在g離本揭*之原理下達成。該輕異或修改 職、視為在本解範叙_為_之申請專職圍所保 13 200841640 • « 【圖式簡單說明】 第一圖顯示傳統之被動式光纖網路之系統架構示意 圖。 第二圖係被動式光纖網路斷線狀況之示意圖。 第三圖係依據本發明一實施例之被動式光纖網路系統 . 架構不意圖。 - 第四圖顯示依據本發明一實施例之主控監測裝置之功 •能方塊圖。 第五圖顯示依據本發明一實施例之回應裝置之功能方 塊圖。 第六圖顯示依據本發明一實施例之光纖鏈路監測方法 之流程圖。 第七圖例示第三圖之光纖網路系統斷線狀況示意圖。 【主要元件符號說明】 100 傳統之被動式光纖網路 110 光纖線路終端設備 120 光分歧器 131 _134 光纖網路單元 200841640 310 光纖線路終端設備 320 光分歧器 330.1-330.4 光纖網路單元 350. 1-350.4 回應裝置 360 主要光纖鍵路 361-364 光纖鏈路 • 340主控監測裝置 340a 中央處理單元 340b 850nm雷射光源 340c 光波長搞合器 340d 780nm光功率檢測單元 350 回應裝置 350a 中央處理單元 350b 780nm雷射光源 350c光波長耦合器 350d 850nm光功率檢測單元’ 601-607 光纖鏈路監測方法之步驟 15200841640 螓 、, invention description: [Technical field of invention] The present invention relates to passive optical network (PON) monitoring technology, in particular to the use of time division multiplexing on a passive optical network (Time Division Multiplexing , TDM) technology enables each Optical Network Unit (ONU) to respond sequentially to monitor the quality of the fiber link. • [Prior Art] _ Due to its large capacity, high reliability, and long transmission distance, optical fibers have gradually become the backbone of telecommunication links. Services that transmit data directly to the client via fiber will be the mainstream of future broadband link applications, such as Fiber To The Cabinet (FTTCab), Fiber To The Curb (FTTC), Fiber to The Fiber To The Building (FTTB) and Fiber To The Home (FTTH), which are collectively referred to as FTTx. Passive Optical Network (PO0 is based on passive optical fiber architecture, which is a competitive link technology. The first figure shows a schematic diagram of a traditional passive optical network 100 system architecture, where the optical line terminal equipment 110 (0ptical Line Terminator, 0LT) is externally connected to the fiber link trunk, and the optical signal transmitted by the fiber line terminal device is transmitted through the optical fiber via the passive component optical splitter (Splitter, SP> 120, and the optical signal is separately broadcasted to each The end user, that is, the optical network unit (Optical Network Unit, 5 200841640 * * .〇·) 131-134. The signal uploaded by the optical network unit 131_134 is coupled to the optical line terminal device via the optical and the splitter 120. 110. With the popularity of fiber-optic network applications, the fault diagnosis of fiber-optic links is becoming more and more important. Referring to the second figure, it shows a schematic diagram of the disconnection of the fiber-optic network. Assume that the optical splitter 120 to the optical network The fiber link between the units 134 is broken, and the maintenance personnel cannot immediately judge the fault as the fiber line terminator U0 to the light after receiving the customer response. The disconnector 120 is disconnected, or the optical splitter I20 to the optical network single 70 134 disconnected. In addition, the externally mounted optical cable may also be affected by external forces, resulting in deterioration of transmission quality, such as during construction. Cautious extrusion, collision, < even bending due to the influence of gravity. This - the deterioration process is slow, often not easy to detect immediately, but the accumulation of fault conditions will cause user inconvenience, affecting goodwill. These failure events have traditionally been The optical link point detection device such as the optical time domain reflector-(four) tiffie_dQmain reflWtxr; 喔) can be used to locate the faults and points. The optical time domain reflector is naturally reflected back by the fiber test signal at different time points. The optical power is compared with the previously recorded original fiber quality trace to determine where the fault code or break point is. However, the optical time domain reflector cannot effectively interpret the tree passive as shown in the first and second figures. The state of the optical fiber network, because of its difficulty (4) occupational students at the end of the seam network (four) structure based on the shortcomings of the above traditional technology, it is necessary to propose - fiber optic chain 6 200841640 road monitoring method The system is not enough for the conventional technology such as fill-in time-domain reflector. It can monitor the recording fiber transmission quality in time to replace the degraded fiber-optic cable in time, and it can be judged immediately when the sudden fiber-optic cable is broken. The invention provides a fiber-to-link monitoring method for a passive optical fiber network, which can instantly determine the disconnection position of the optical fiber link and shorten the maintenance time. One objective is to propose a fiber optic link monitoring method for passive fiber optic networks to detect the quality of the fiber link and replace the degraded fiber optic cable early. It is still another object of the present invention to provide an apparatus for implementing the optical fiber link monitoring method of the above-described passive optical network. In accordance with the above objects, the present invention provides a fiber optic link monitoring system including a master monitoring device and a plurality of responding devices, wherein the master monitoring device broadcasts a specific command to the plurality of responding devices to request one of the plurality of responding devices The responding device continuously returns a specific response optical signal of a first specific time length, and the master monitoring device determines whether the specific fiber link connected to one of the specific response devices is normal according to the condition of the specific response optical signal receiving. 7 200841640 The present invention also provides a fiber optic link monitoring method, comprising the steps of: broadcasting a specific command from a master monitoring device to a plurality of responding devices to request that one of the plurality of responding devices continues to transmit back one of the responding devices Determining a specific response optical signal by one of the first specific time lengths; returning the specific response optical signal to the primary monitoring device from the specific response device; and determining the specific fiber link connected to the specific response device according to the condition of the specific response optical signal reception ' Nothing is normal. [Embodiment] A detailed description of some embodiments of the present invention is as follows, but the present invention can be widely applied to other embodiments in addition to the detailed description. That is, the scope of the present invention is not limited by the embodiments which have been proposed, and the scope of the claims of the present invention shall prevail. Further, in order to provide a clearer description and a better understanding of the present invention, the various parts of the drawings are not drawn according to their relative dimensions, and some dimensions have been exaggerated compared to other related dimensions; the unrelated details are not Completely drawn 'to make the map not simple. FIG. 3 is a schematic structural diagram of a fiber optic network system 300 having a fiber optic link monitoring function according to an embodiment of the present invention, which includes an optical fiber line terminal device 310, a main control monitoring device 340, an optical splitter 320, and a response device 350. -35CK 4 (hereinafter collectively referred to as responding device 350) and fiber optic network unit 8 200841640 • Having committed 0·1—330·4. In comparison with the conventional fiber optic network system 100 of the first figure, it is known that the master monitoring device 340 and the response device 350 are the main devices newly added to perform the monitoring function of the present invention. The fiber optic line termination device 310' is coupled to a master monitoring device 340 that is coupled to the optical splitter 32A via a primary fiber link 360. The optical splitter 320 is coupled to the response device 350. 1-350.4 via fiber optic links 361-364, respectively. The response devices 350· 1-350.4 are connected to the respective fiber optic network units 33 〇. In the present embodiment, the master monitoring device 340 broadcasts an optical signal having a wavelength of 850 nm (narometer; nanometer) by Time Division Multiplexing (TDM) technology to command each response device to continuously send a response to the optical signal. The length of time, for example 2 seconds. The optical splitter 320 forwards the broadcast optical signals to respective response devices 350· 1-350.4. It should be noted that 85〇11111 is only an example. The broadcast optical signal does not limit the specific wavelength, and it only needs to avoid the wavelength used by the existing communication optical signal. Continuous illumination for 2 seconds is also not limited, and the specific length of time is sufficient to measure the response optical power. The response device 350. 1 - 350· 4 returns the optical signal of the 780 leg to the master monitoring device 340 after receiving the illumination command. This return wavelength is also only an example, which only needs to avoid the existing transmission wavelength. After receiving the returned optical signal, the master monitoring device 340 can analyze and record the optical power to determine whether the fiber link 330· 1-330.4 connected to the response device 350· 1-350.4 is normal. For example, if 200841640 does not receive the returned optical signal, the returned optical signal power is too low (less than a specific threshold value) or too high (greater than another specific threshold value), then it can be determined that the connection to the device 350 · The fiber link 330·330·4 of Bu 350·4 may occur differently. In addition, based on the status of all of the backhaul optical signals, it can be comprehensively determined whether the location of the fault is located between the primary monitoring device 340 and the optical fiber link 32. The fourth figure shows a functional block diagram of a master monitoring device 34 according to an embodiment of the present invention, which includes an optical wavelength coupler 340c, an optical power detecting unit 340d, a central processing unit 34A, and a laser light source 34A. . The optical wavelength combiner 340c is coupled to an external fiber line termination noise 31 (not shown) and a primary fiber link 360 (not shown). The optical wavelength converter 340c is also connected to the laser light source 34〇b and the optical power detecting unit 34〇d. The laser light source 340b and the optical power detecting unit 340d are both connected to the central processing unit 340a. The central processing unit 340a requires the laser light source 340b to transmit a light signal having a wavelength of 850 nm to carry a specific command to command a specific responding device (for example, the responding device 350.1) ) Respond to a light signal. The 85 〇 nm optical signal is broadcasted externally by the optical wavelength coupler 340c and the connected fiber link. Upon receipt of the optical signal of the 780 nm wavelength returned from the particular responding device, it is transmitted to the optical power detecting unit 34〇d via the optical wavelength coupler 340c. The result of the measurement by the central processing unit 340a to the optical power detecting unit 34〇d is analyzed in accordance with the method of the aforementioned 200841640. If the result is normal, the central processing unit 3 will start and move the next test device of the response device; if the result is abnormal, the central processing will determine that the abnormal condition is disconnection, line deterioration or other situation, and the sub-activation is related. Alert or handler. The central processing unit can include a memory device to record historical optical power measurements for determining the quality degradation of the line. • Figure 5, 4 is not in accordance with the present invention - the response device of the embodiment of the power of the month b block о its package 3 light wave coherence device, the optical power detection unit 3' towel processing early 35 〇 a and laser light source this. The light wavelength shank is connected to the external light _ road unit (not shown (4)) and the fiber key (not shown). The optical wavelength light combiner is also connected to the laser light source 350b and the optical power detecting unit 35〇d. The laser light source b and the optical power detecting unit 350d are both connected to the central processing unit. The 85Gnm wavelength optical signal from the master supervisory device is transmitted to the optical power detection 350d via the optical wavelength coupler 35A, and the specific command is parsed by the central processing unit 35A. If the central processing unit 350a finds that the target of the specific command is the response device 700, the laser source 35〇1) is required to continuously send a light signal with a wavelength of 780 nm through the optical wavelength coupler 35 (: and the fiber link is transmitted back) Figure 6 is a flow chart showing a method for monitoring an optical fiber link according to an embodiment of the present invention, which includes steps 601 to 607. In step 601, the main control device of the optical fiber terminal device broadcasts a specific command to 11 200841640 > Response device for each fiber network unit end. In this embodiment, the specific command is carried by a wave of light of 850 nm, and a specific response device is commanded to respond to an optical signal for 2 耖. In step 602, all the responding devices receive the specific command. In step 6〇3, the #定定回装置 device in the specific command is returned by the optical signal with a wavelength of 780 nm for a duration of -2. In step 6〇4 The master monitoring device analyzes the optical signals returned by the specific response device during the time, such as the presence or absence of the signal and the power color of the park, the temple. In step 605, The system will further judge whether the fiber link is degraded or disconnected according to the analysis result. If the optical signal of the returned signal is normal, then the system will directly execute step 607 to start the next response device: 43⁄4. Abnormal conditions, such as the received optical power value below 弋 'quasi value below' means that the link may be degraded; or there is no light wheeling at all, - 'is indicating that there may be a disconnection situation failure; such abnormal conditions Lu Jieyu The system starts the alarm mechanism of step 606. The mechanism can send a video signal in the form of video or audio through a human machine to remind the manager that there is an abnormal situation. At the same time, the system also performs step β〇7 to start the next response. , the detection procedure, by the subsequent response to the optical signal returned by the device to determine the fiber position of the obstacle. Figure, ^ Figure 2 is not the second picture of the fiber-optic network system _ disconnection status indication 35 〇 卜 364 * Do not denote the optical link between the optical splitter, 320 to the response device • 35〇·4, the disconnection condition occurs in the optical fiber between the optical splitter 12 200841640 320 and the response device 350·4 Road 364. According to the method of the present invention, the master monitoring and monitoring device 34 can successfully receive the 回·2 and 350.3 backhaul from 35〇1 when performing the detecting procedures of the response devices 35〇1 and 3, such as the month 350.3. The optical signal indicates that the optical fiber line terminal device 3丨〇 to the eight-eighth device 320, and the optical splitter 32〇 to the response device 35. The line between 0·2 and 350.3 is normal. The master monitoring device 34 is executing. In response to the _350.4 _ program, an abnormal condition is found, indicating that the fiber line backup 310 to the optical splitter 320 or the optical splitter 3, , and the end device is 35 〇 4 between the line faults; but may be 350. 1, 350 · 2 and 350·3 of the investigation and determination of the optical fiber line terminal equipment 310 to the optical splitter 32 〇 between the green, . 'The green is slightly positive, so the broken line should occur in the light divergence cry 3 " Re-response between Rosie 350.4. Maintenance personnel can bring relevant equipment to the scene quickly to check the clothing # save time. To take more, the specific wavelengths of the above-mentioned optical signals, such as 850 nm and (10), and the specific length of time of the transition are all examples for convenience of explanation. The person of Xisisi (4) can be replaced by other alternatives. Features and features. The various embodiments are merely examples of possible implementations, and many variations or modifications can be made without departing from the principles of the invention. The singularity or modification of the job is considered to be in the application of the full-time coverage of the essay. 13 200841640 • « [Simple description of the diagram] The first figure shows the schematic diagram of the system architecture of the traditional passive optical network. The second figure is a schematic diagram of the disconnected state of the passive optical network. The third figure is a passive optical network system in accordance with an embodiment of the present invention. The architecture is not intended. - Figure 4 is a block diagram showing the function of the master monitoring device in accordance with an embodiment of the present invention. The fifth figure shows a functional block diagram of a response device in accordance with an embodiment of the present invention. Figure 6 is a flow chart showing a method of monitoring an optical fiber link in accordance with an embodiment of the present invention. The seventh figure illustrates a schematic diagram of the disconnection condition of the optical network system in the third figure. [Main component symbol description] 100 Traditional passive optical network 110 Optical fiber terminal equipment 120 Optical splitter 131 _134 Optical network unit 200841640 310 Optical line terminal equipment 320 Optical splitter 330.1-330.4 Optical network unit 350. 1-350.4 Response device 360 main fiber link 361-364 fiber link • 340 master monitoring device 340a central processing unit 340b 850 nm laser source 340c optical wavelength combiner 340d 780 nm optical power detection unit 350 response device 350a central processing unit 350b 780 nm ray Light source 350c optical wavelength coupler 350d 850nm optical power detection unit '601-607 Step 15 of fiber link monitoring method