200841616 九、發明說明： 【發明所屬之技術領域】 本發明係有關於一種監測被動式光纖網路鏈路之方法 與裝置，特別是關於利用光纖網路單元群組和光纖鏈路之 對應關係偵測樹狀型被動式光纖網路之異常光纖鏈路之技 術。 【先前技術】 光纖網路的光纖常會因外在環境的影響，例如溫度變 化、外力壓迫、甚至人為的蓄意破壞而受損或斷裂，致使 光訊號的傳遞中斷或是損耗增加。因此監測光纖網路是必 要的措施，然而成本和效率也應納入考量。 第一圖顯示習知之樹狀型被動式光纖網路架構100, 其包含光纖線路終端設備 102、光分歧器 (Sp 1 itter)104-112及光纖網路單元121-136。在本圖中光 分歧器104-112皆為1:4的分離器，所以共有16個光纖網 路單元121-136。光纖線路終端設備102利用分時多工技 術和光纖網路單元121-136。在正常情況下，光纖線路終 端設備102會持續接收到來自光纖網路單元121-136之回 傳光訊號。 6 200841616 光纖線路終端設備102通常架設在局端機房了它 •一種介於被動式光纖網路系統（〇LT客戶端）和骨幹網路 (0LT網路端）之間之匯流/分流服務。意即，從客戶端獲 取之資料流處理後匯集，送至網路端連至骨幹網路，或將 網路端的資料流處理後分至客戶端。客戶端使用被動光纖 網路介面’而網路端通常裝設同步光纖網路或Τ3等介面。 光纖網路單元（Optical Network Unit，〇而）121-136 ’ 如同乙太網路（Ethernet)裝置一般，每個〇簡均有唯一的 身分序號（ID)，一般會架置在客戶端附近或特定設施内。 它提供一種介於被動式光纖網路系統（〇網路端）和客戶 的個人電腦或内部區域網路（0NU客戶端）之間的服務介 面。 傳統的光纖鏈路監測方式常利用光時域反射器 (Optical Oime-Domain Ref lectometry; 0TDR)來測量光訊號的 、傳遞有無異常。光時域反射器本身是較為昂責的量測儀 器’量測方法是在光纖的一端打入固定寬度的光脈衝，並 使用高感應的光偵測器在同一端不斷接收光脈衝打出後不 同時間到達的反射光。由於光在光纖中會不斷的損耗，因 此可以得到相關的光時域反射裔路桂圖（原理是所收到的 光反射會隨著時間增加而減小），來了解光傳輪的損耗情 況。當此路徑圖某處有異常光損耗時，便可以知道光纖的 200841616 ♦ ..... 秦 哪個地方有異常情況。但前提是每個〇圆到光分歧器 * (Splitter)的距離必須明顯不同，否則無法分辨是哪一段 光纜有異常情況。 如果兩個以上的分支光纖網路長度相近時，將無法直 接在光時域反射器的路徑圖上明確分辨何處發生異常情 況。這時只能採用費時的方法，在光分歧器端直接量測這 些光纖網路的狀態，而無法在頭端監測。 ί 因此亟需提出一種適用於分支光纖網路長度相近並能 節省成本和時間的光纖網路監測方法和裝置，以改進傳統 使用光時域反射器在光纖網路監測上的缺失。 【發明内容】 本發明的目的之一在於提出一種被動式光纖網路鏈路 I測的方法，其利用光纖網路單元群組和光纖鏈路之對應 ^ 關係偵測樹狀型被動式光纖網路中光纖鏈路之異常情況。 本發明的另一目的在於提出一種被動式光纖網路鏈路 監測的裝置，以偵測樹狀型被動式光纖網路中光纖鏈路之 異常情況。 根據上述之目的，本發明提出一種被動式光纖網路之光 纖鏈路監測方法，其係應用於光纖網路架構中，此光纖網路架構 包含光纖線路終端設備、第一光分歧器以及複數光纖網路單元 (0NU)，而上述光纖線路終端設備、第一光分歧器以及複數光纖網 200841616 路單元間皆利用光纖鏈路連結，此光纖鏈路監測方法包含下列步 驟·決定複數群組，使得每一群組包含此複數光纖網路單元之一 部分，將上述每一群組分別透過光纖鏈路連接至第一光分歧器； 由光纖線關^設備讀取複數群組之回傳光訊號絲能量，以判 斷光纖線路終端設備、第—光分歧ϋ以及複數群組間之光纖鏈路 判斷方式包含·若複數群組其中之一特定群組中之回傳光 減或光能量均屬不正f狀態，代表此特定群組與第-光分歧器 間之光纖鏈路呈現異常狀態，其巾之絲祕終端設備透過主要 光纖鏈路連接至第一光分歧器。 本發明亦提tb-種具有光麵路制魏之光_路系統， 其包έ ·光纖線路終端設備、光分歧器以及複數光纖網路單元， 其中上述光纖線路終端設備、光分歧H以及複數先細路單元間 皆利用光纖鏈路連結，光纖線路終端設備透過一主要光纖鏈路連 接至光分歧器，複數光纖網路單元區分為複數群組，且光纖線路 終端設備内部至少設有—讀取單元，此讀取單元係用以讀取前述 複數群組之回傳疏#或纽號，魏翻傳之光能量或光訊號 之強度，判斷光纖線路終端設備、光分歧器以及複數群組間之光 纖鏈路狀態。 本杳明亦表:出一種被動式光纖網路之光纖鏈路監測裝置， 其係應用於光纖瓣_巾，此賴網路架構包含光纖線路終端 設備、光分歧H以及複數先纖娜單元，上述先·路終端設備、 200841616 光分歧器以及複數光纖網路單元間皆利用光纖鏈路連結，複數光 纖網路單元區分為複數群組，此光纖鏈路監測裝置包含：一光能 量擷取元件’用以擷取上述複數群組之回傳光能量；以及一監測 模組，用以檢測回傳光能量之強度，並依據此回傳光能量之強度 判所光纖線路終端設備、光分歧器以及複數群組間之光纖鏈路狀 態。 【實施方式】 f . 以下配合圖式詳細說明本發明之較佳實施例。然而， 除了所舉實施例之外，本發明還可以廣泛地在其他的實施 例施行。再者，為求圖式之簡潔，圖式内不相關之細節部 份並未完全繪出。不同圖式中相同的編號或標記代表相同 的元件或概念。 第二圖顯示依據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200，其包含光纖線路終端設備202、 第一光分歧器208、複數個第二光分岐器210-216、以及複 數個光纖網路單元（〇NUs)221-236。光纖線路終端設備202 透過主要光纖鏈路240連接至第一光分歧器208。第一光 分歧器208透過光纖鏈路250-256分別連接至第二光分岐 器210-216。第二光分岐器210-216又透過如圖所示之其 他光纖鏈路分別連接至光纖網路單元221-236。 200841616 複數個第二光分岐器210-216以及複被個光纖網路單 元221-236被區分為如圖所示之群組26〇—263。群組26〇 包含第二光分岐器210和光纖網路單元221—224，群組261 包含第二光分岐器212和光纖網路單元225—228，群組262 包含第一光分岐裔214和光纖網路單元229—232，群組263 包含第二光分岐器216和光纖網路單元233_236。 光纖線路終端設備2〇2叫有讀取料以讀取來 自群組260-263之回傳光訊號或光能量。讀取單元依 據此等回傳之光訊號或光能量之強度判斷各個光纖鍵路是 否有異常狀態或故障。例如’若群組26()回傳之光訊號或 光能量均不正常（但其他群組正常），則判斷連接至群組260 之光纖鏈路250可能有異常狀態。又如，若群組削 回傳之光訊號或光能量均不正常，則_第—光分歧器2〇8 =域線料端設錢2間之㈡域麟⑽係處於異 'X如’方群、、且26〇中僅有部分光纖網路單元之回 ，光訊號或錢量U常，關^接連接韻等不正常 光纖網路單元之光纖鏈路異常。 讀取單元204之内部架構可以是，但不限於，第六圖 =之監測齡206和光能量•元件2〇9之組合，詳見 弟，、圖之說明。 11 200841616 以下對各種鏈路故障情況和擷取自各個光纖網路單元 之回傳光能量或光功率之關係加以說明，以幫助對本發明 原理之了解。為簡潔起見，光纖網路單元在以下說明有時 將簡稱為0NU或ONUs。在以下的說明中，假設整體鏈路皆 正常時，各〇圓之回傳光功率分布圖係如第三圖所示（第三 圖中之代號A-P分別代表〇腿22卜236，第三A、三B和三 C圖亦然）。此處為說明方便起見，假設⑽u 221-236於正 ’ 常狀況下均回傳大致相同的光功率強度，實際情況可能有 所差異。換言之，各〇NU回傳光功率之正常範圍可以彼此 不同，網管單位可以依實際情況設定所有〇NU回傳光功率 之正常範圍，再依此進行比對。此外，以下說明之舉例均 衍用第二圖之架構、名稱和編號。 第二A圖例示第二圖之被動式光纖網路2〇〇發生之一 鏈路斷線情況示意圖。此例中，讀取單元204和第一光分 v 歧器208間之主要光纖鏈路240的某處發生斷線。此時， 讀取單元204將偵測到如第三A圖所示之0NU回傳光功率 分布圖。因為主要光纖鏈路24〇是有群組260-263内之所 有⑽Us對光纖線路終端設備202通信之必經路線，其一旦 斷線則所有回傳信號將同時消失。由此可知，當所有群組 260-263中之所有〇NUs之回傳信號均處於不正常範圍之時 即可判定該群組對應之主要光纖鏈路240可能出現問題。 12 200841616 第二B圖顯示第二圖之被動式光纖網路200發生之另 一鏈路斷線情況示意圖。此例中，第一光分歧器2〇8和第 二光分歧器210之間的光纖鏈路250的某處發生斷線。此 時，讀取單元204將偵測到如第三b圖所示之〇冊回傳光 功率分布圖。因為光纖鏈路250是⑽Us 22卜224對光纖線 路終端設備202通信之必經路線（且網路中之其他〇對光 纖線路終端設備202之通信均無須經過光纖鏈路250)，光 纖鏈路250 —旦斷線則對應於⑽US 221-224之回傳信號均 勢必消失。由此可知，若將ONUs 221-224歸為同一群組 26〇，則當此群組中之所有〇NUs之回傳信號均處於不立常 範圍之時即可判定該群組對應之光纖鏈路250可能出現問 題。 第二C圖顯示第二圖之被動式光纖網路200發生之另 —鏈路斷線情況示意圖。此例中，光分歧器210和0NU224 之間的光纖鏈路的某處發生斷線。此時，讀取單元204將 偵測到如第三C圖所示之0NU回傳光功率分布圖。因為斷 線處是0NU 224對光纖線路終端設備202通信之必經路線 (且網路中之其他〇厕對光纖線路終端設備202之通信均難 須經過斷線之光纖鏈路），故斷線處對應於0NU 224之函傳 信號勢必消失。由此可知，0NU 224之回傳信號處於不疋 常範圍之時即可判定對應之光纖鏈路可能出現問題。 13 200841616 由上之揭不可知本發明亦提出一種被動式光纖網路 之光纖鏈路監測方法。第四圖顯示根據本發明一實施例之 被動式光纖網路鏈路監測方法，此方法可以應用於第二圖 =示之光纖網路架構中，以下說明將參照第二圖之編號。 第四圖所示之光纖網路鏈路監測方法包含步驟402_406。 步驟撤決定複數群組26G_263，使得每组⑽―聊 包含複數光纖網路單元22卜236之-部分。例如，如第二 f圖之說明決定群組26Q_263分別包含之内容。同一群組中 之所有光纖網路單元和光纖線路終端設備2G2通信時均須 透過同-特定光纖鏈路，且不屬於此群級之其他網路單元 和光纖線路終端設備2〇2通信時均無須透過此特定光纖鍵 路。依據此原則，每一群組均可以對應至—特定光纖鏈路 (例如於第二圖中，包含圆s 22卜224之群組26〇對應至 ，纖鏈路250)。上述群組亦可以如第二圖所示更分別包含 " 第二光分歧器210-216,以方便說明其和對應之特定光纖 鏈路之連接關係。步驟404將每一群組分別透過其對應之 、纖鏈路連接至第一光分歧益208。步驟406由光纖線路終 端設備202讀取複數群組260-263之回傳光訊號或光能量，以判 斷光纖線路終端設備2〇2、第一光分歧器208以及複數群組 260 263間之光纖鏈路狀態。判斷光纖鏈路狀態之方式詳見第四 A圖之說明。 200841616 * 第四A圖顯示根據本發明一實施例之被動式光纖網路 ^ 光纖鏈路監測方法之光纖鏈路狀態判斷流程圖。以下說明 仍參照第二圖之編號。步驟410檢查所有群組260-263之 回傳光訊號或光能量是否均處於不正常狀態。若其均處於 不正常狀態，則執行步驟410a，告警主要光纖鏈路240處 於異常狀態；否則則繼續執行步驟412。 步驟412檢查群組260-263中之一特定群組之回傳光 訊號或光能量是否均處於不正常狀態。若其均處於不正常 狀態，則執行步驟412a，告警該特定群組與第一光分歧器 208間之光纖鏈路處於異常狀態；否則則繼續執行步驟 414。步驟414判斷是否所有群組均檢查完畢，若尚有未檢 查之群組，則回到步驟412繼續檢查下一特定群組；若檢 查完畢則繼續執行步驟416。 步驟416檢查群組260-263中之一特定光纖網路單元 之回傳光訊號或光能量是否處於不正常狀態。若其處於不 正常狀態，則執行步驟416a，告警直接連接至該特定光纖 網路單元之光纖鏈路呈現異常狀態；否則則繼續執行步驟 418。步驟418判斷是否所有光纖網路單元均檢查完畢，若 尚有未檢查之光纖網路單元，則回到步驟416繼續檢查下 一特定光纖網路單元；若檢查完畢則結束本流程。 15 200841616 第四圖和第四A圖之流程可由第六圖中之中央處理單 •元206A主控。判定回傳光訊號或光能量是否處於不正常狀 態係依據分別為各光纖網路單元設定之回傳光訊號正常強 度範圍’不同的光纖網路單元其訊號正常強度範圍可以不 同。 第五圖顯示根據本發明另一實施例之具有光纖鏈路監 測功能之光纖網路系統200A之架構圖，其包含光纖線路終 r 端設備202、光能量擷取元件209、監測模組206、光分歧 器208-216及光纖網路單元221-236。光能量擷取元件209 連接至光纖線路終端設備202及監測模組206，並透過光 纖鏈路240連接至光分歧器208。光分歧器208透過光纖 鏈路250、252、254及256分別連接至光分歧器210、212、 214及216。此四個光分歧器210-216又分別透過光纖鏈路 (280-283、284-287、288-291、292-295)連接至光纖網路 v 單元（221-224、225-228、229-232、233-236)。此架構基 本上是在習知架構中之光纖線路終端設備202與光分歧器 208之間加入一光能量擷取元件209，和一監測模組206。 實務上，光能量擷取元件209和監測模組206可整合入同 一模組，甚至整合入光纖線路終端設備202。 光能量擷取元件209可以是包含一光分歧器和一光濾 波（optical filter)之模組或是包含一光分歧器和一分波 16 200841616 多工器（wave division module ; WDM)之模組，然並不以此 e為限。光能量擷取元件209可以基於分時多工協定擷取來 自光纖網路單元221-236回傳至光纖線路終端設備202之 通信光信號能量，並傳送至監測模組206以進一步分析。 監測模組206之功能在於檢測並分析光能量擷取元件209 擷取之光能量，其内部架構於第六圖之實施例有更詳細之 說明。監測模組206以群組為單位對接收之光纖網路單元 ， 回傳信號進行分析。 監測模組206即基於如上所述將網路中所有光纖鏈路 對應至特定群組之概念，對光能量擷取元件209擷取之光 能量進行必要之轉換和分析。當發現同一群組中之所有光 纖網路單元和光纖線路終端設備202之通信均出現問題 時，即判定該群組對應之光纖鏈路可能處於不正常之狀 態，而應進一步檢修。詳細之監測方法請參見第四圖和第 、 四Α圖實施例之說明。 第六圖顯示第五圖之監測模組206根據本發明一實施 例之功能方塊圖，其包含中央處理單元206A和光功率檢測 元件206B。光功率檢測元件206B可以是包含一光二極體 (photo diode)之光訊號偵測和轉換元件，然並不以此為 限。其功能在於執行光功率之檢測功能，例如將光能量轉 換成電子訊號以利後續之分析動作。中央處理單元206A可 17 200841616 以是一般泛用式微處理器（microprocessor)，用以進一步 ‘分析光功率檢測元件206B轉換後之信號，並據以判斯是否 有光纖鏈路發生斷線或異常情況。第六圖並顯示監測模組 206透過光能量擷取元件209連接至光纖線路終端設備202 和被動式光纖網路之主要光纖鏈路240。實務上，如前所 述，光能量擷取元件209和監測模組206可整合入同一模 組，甚至整合入光纖線路終端設備2 0 2 ^而成為如第二圖 ， 所示之讀取單元204 〇 以上所述僅為本發明之較佳實施例而已，並非用以限 定本發明之申請專利範圍；凡其它未脫離發明所揭示之精 神下所完成之等效改變或修飾，均應包含在下述之申請專 利範圍内。 【圖式簡單說明】 第一圖顯示習知之樹狀型被動式光纖網路架構。 第二圖顯示根據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。 第二A圖至第二C圖例示第二圖之被動式光纖網路發 生各種鏈路斷線之示意圖。 第三圖顯示正常之光纖周路單元回傳光功率分布圖。 第三A圖至第三C圖分別顯示對應於第二A圖至第二 C圖斷線情況之光纖網路單元回傳光功率分布圖。 18 200841616 第四圖顯示根據本發明一實施例之被動式光纖網路光 ‘ 纖鏈路監測方法。 第四A圖顯示根據本發明一實施例之被動式光纖網路 光纖鏈路監測方法之光纖鏈路狀態判斷流程圖。 第五圖顯示根據本發明另一實施例之具有光纖鏈路監 測功能之光纖網路系統。 第六圖顯示第五圖之監測模組根據本發明一實施例之 f 功能方塊圖。 【主要元件符號說明】 100樹狀型被動式光纖網路架構 102光纖線路終端設備 104、106、108、110、112 光分歧器 121-136光纖網路單元（ONU) 200/200A具有鏈路監測功能之被動式光纖網路 202 光纖線路終端設備 204 讀取單元 206監測模組 206A中央處理單元 206B 光功率檢測單元 208第一光分歧器 209光能量擷取元件 19 200841616 210、212、214、216 第二光分歧器 221-236光纖網路單元（0NU) 240主要光纖鏈路 250 、 252 、 254 、 256 260-263 群組 280-295光纖鍵路 光纖鏈路 4 0 2 - 418被動式光纖網路光纖鏈路監測方法步驟 410a/412a/416a被動式光纖網路光纖鏈路監測方法之告 警步驟 20200841616 IX. Description of the Invention: [Technical Field] The present invention relates to a method and apparatus for monitoring a passive optical network link, and more particularly to the use of a correspondence between a fiber network unit group and a fiber link The technology of an abnormal fiber link in a tree-type passive optical network. [Prior Art] Fibers of fiber-optic networks are often damaged or broken due to external environmental influences such as temperature changes, external force compression, and even intentional vandalism, resulting in interruption of transmission of optical signals or increased loss. Therefore, monitoring fiber-optic networks is a necessary measure, but cost and efficiency should also be taken into account. The first figure shows a conventional tree-like passive fiber optic network architecture 100 that includes fiber optic line termination devices 102, optical splitters (104), and fiber optic network units 121-136. In this figure, the optical splitters 104-112 are all 1:4 splitters, so there are a total of 16 fiber optic network units 121-136. The fiber line termination device 102 utilizes time division multiplexing and fiber optic network units 121-136. Under normal conditions, the fiber optic line termination device 102 will continue to receive the return optical signals from the fiber optic network units 121-136. 6 200841616 The fiber-optic line termination equipment 102 is usually installed in the central office. • A convergence/diversion service between the passive optical network system (〇LT client) and the backbone network (0LT network). That is to say, the data stream obtained from the client is processed and collected, sent to the network to connect to the backbone network, or the data stream of the network is processed and distributed to the client. The client uses a passive optical network interface' and the network side usually has a synchronous optical network or Τ3 interface. Optical Network Unit (Optical Network Unit) 121-136 'As with Ethernet devices, each computer has a unique ID number, which is usually placed near the client or Within a specific facility. It provides a service interface between a passive optical network system (〇 network side) and a customer's personal computer or internal area network (0NU client). Traditional optical fiber link monitoring methods often use Optical Oime-Domain Ref ectometry (0TDR) to measure the presence or absence of optical signals. The optical time domain reflector itself is a more rigorous measuring instrument. 'Measurement method is to insert a fixed-width light pulse at one end of the fiber, and use a high-inductance photodetector to continuously receive the light pulse at the same end. The reflected light that arrives at the time. Since the light will continue to be lost in the fiber, the relevant optical time domain reflectance map can be obtained (the principle is that the received light reflection will decrease with time) to understand the loss of the light transmission wheel. . When there is abnormal light loss somewhere in this road map, you can know the optical fiber's 200841616 ♦ ..... Qin where there is an abnormal situation. But the premise is that the distance from each round to the light splitter * (Splitter) must be significantly different, otherwise it is impossible to tell which section of the cable is abnormal. If more than two branch fiber networks are of similar length, it will not be possible to clearly distinguish where an anomaly occurs directly on the path map of the optical time domain reflector. At this time, only the time-consuming method can be used to directly measure the state of these optical networks at the optical splitter end, and cannot be monitored at the head end. Therefore, there is a need to propose a fiber optic network monitoring method and apparatus suitable for branch fiber networks of similar length and cost and time to improve the lack of traditional optical time domain reflectors for fiber network monitoring. SUMMARY OF THE INVENTION One object of the present invention is to provide a passive optical network link I measurement method, which uses a corresponding relationship between a fiber network unit group and a fiber link to detect a tree-type passive optical network. Abnormal condition of the fiber link. Another object of the present invention is to provide a passive fiber optic network link monitoring device for detecting anomalies in a fiber optic link in a tree-type passive optical network. According to the above object, the present invention provides a fiber optic link monitoring method for a passive optical fiber network, which is applied to a fiber network architecture, which includes an optical fiber line terminal device, a first optical splitter, and a plurality of optical fibers. The circuit unit (0NU), and the above optical fiber line terminal device, the first optical splitter, and the plurality of optical fiber network 200841616 road units are all connected by using a fiber link, and the fiber link monitoring method includes the following steps: determining a plurality of groups, so that each A group includes a portion of the plurality of fiber optic network units, each of the groups is respectively connected to the first optical splitter through a fiber link; and the optical fiber line device reads the energy of the return optical signal of the plurality of groups In order to determine the fiber line terminal device, the first-light divergence, and the fiber link determination mode between the plurality of groups, if the return light reduction or the light energy in one of the plurality of groups is a non-positive f state , representing that the fiber link between the specific group and the first-light splitter presents an abnormal state, and the wire terminal device of the towel is connected through the main fiber link. A first optical splitter. The invention also provides a tb-type system with a smooth surface system Weizhiguang, which comprises an optical fiber line terminal device, an optical splitter and a plurality of optical fiber network units, wherein the optical fiber line terminal device, the optical divergence H and the complex first fine circuit Each of the units is connected by a fiber link, and the fiber line terminal device is connected to the optical splitter through a main fiber link, the plurality of fiber network units are divided into a plurality of groups, and at least the read unit is disposed inside the fiber line terminal device. The reading unit is configured to read the backhaul # or the number of the plurality of groups, the intensity of the light energy or the optical signal of the Wei turn, and determine the optical fiber terminal device, the optical splitter, and the optical fiber between the plurality of groups Link status. Benming also shows: a passive fiber-optic network fiber link monitoring device, which is applied to a fiber-optic stencil, which comprises a fiber-optic line terminal device, a light divergence H, and a plurality of precursor fiber units, The first-channel terminal device, the 200841616 optical splitter, and the plurality of optical network units are all connected by a fiber link, and the plurality of optical network units are divided into a plurality of groups, and the optical link monitoring device includes: a light energy capturing component And a monitoring module for detecting the intensity of the returned light energy, and determining the optical fiber line terminal device, the optical splitter, and the intensity of the returned light energy according to the monitoring module The status of the fiber link between the plural groups. [Embodiment] f. The preferred embodiment of the present invention will be described in detail below with reference to the drawings. However, the present invention can be widely applied to other embodiments in addition to the embodiments. Furthermore, in order to clarify the schema, the details of the unrelated details in the schema are not completely drawn. The same numbers or symbols in the different drawings represent the same elements or concepts. The second diagram shows a fiber optic network system 200 having a fiber optic link monitoring function, including an optical fiber line termination device 202, a first optical splitter 208, and a plurality of second optical splitters 210-216, in accordance with an embodiment of the present invention. And a plurality of fiber optic network units (〇NUs) 221-236. The fiber optic line termination device 202 is coupled to the first optical splitter 208 via a primary fiber optic link 240. The first optical splitter 208 is coupled to the second optical splitters 210-216 via fiber optic links 250-256, respectively. The second optical splitters 210-216 are in turn coupled to the fiber optic network units 221-236 via other fiber optic links as shown. 200841616 The plurality of second optical splitters 210-216 and the complex optical network units 221-236 are divided into groups 26〇-263 as shown. Group 26A includes a second optical splitter 210 and fiber optic network units 221-224, group 261 includes a second optical splitter 212 and fiber optic network units 225-228, and group 262 includes a first optical subdivision 214 and The fiber optic network units 229-232, the group 263 includes a second optical splitter 216 and a fiber optic network unit 233_236. The fiber optic line termination device 2〇2 is called a read material to read the backhaul optical signal or light energy from the group 260-263. The reading unit determines whether each fiber-optic key has an abnormal state or a fault according to the intensity of the returned optical signal or optical energy. For example, if the optical signal or optical energy returned by the group 26() is abnormal (but other groups are normal), it is judged that the optical fiber link 250 connected to the group 260 may have an abnormal state. For example, if the light signal or light energy of the group is not normal, then the _ first-light splitter 2〇8 = the domain line material end is set to 2 (2) domain lin (10) is in the same 'X as ' In the square group, and only 26% of the fiber-optic network units are back, the optical signal or the amount of money is often, and the fiber link of the abnormal fiber-optic network unit is abnormal. The internal architecture of the reading unit 204 can be, but is not limited to, a combination of the monitoring level 206 and the optical energy component 2〇9 in the sixth figure, see the description of the figure. 11 200841616 The following is a description of the various link failure scenarios and the relationship between the returned optical energy or optical power taken from each fiber optic network unit to aid in understanding the principles of the present invention. For the sake of brevity, the fiber optic network unit will sometimes be referred to as ONU or ONUs in the following description. In the following description, assuming that the overall link is normal, the optical power distribution map of each round is as shown in the third figure (the code AP in the third figure represents the leg 22 22, 236, the third A, respectively). , three B and three C pictures are also the same). For the sake of convenience of explanation, it is assumed that (10) u 221-236 returns substantially the same optical power intensity under normal conditions, and the actual situation may be different. In other words, the normal range of each NU return optical power can be different from each other, and the network management unit can set the normal range of all 〇NU return optical power according to the actual situation, and then perform comparison according to this. In addition, the examples described below all use the architecture, name, and number of the second figure. Figure 2A illustrates a schematic diagram of one of the passive disconnection of the passive optical network in the second diagram. In this example, a disconnection occurs somewhere in the primary fiber link 240 between the read unit 204 and the first optical splitter 208. At this time, the reading unit 204 will detect the ONU return optical power distribution map as shown in FIG. Since the primary fiber link 24 is a mandatory route for all (10) Us to the fiber line termination device 202 in the group 260-263, once the wire is broken, all of the return signals will disappear at the same time. It can be seen that when all the back signals of all the NUs in the group 260-263 are in an abnormal range, it can be determined that the main fiber link 240 corresponding to the group may have a problem. 12 200841616 Figure 2B shows a schematic diagram of another link disconnection that occurs in the passive optical network 200 of Figure 2. In this example, a disconnection occurs somewhere in the fiber link 250 between the first optical splitter 2〇8 and the second optical splitter 210. At this time, the reading unit 204 will detect the registered light power distribution map as shown in the third b diagram. Because the fiber link 250 is the necessary route for the (10)Us 22 224 to communicate with the fiber line termination device 202 (and the other ports in the network do not need to pass through the fiber link 250 for the communication of the fiber line termination device 202), the fiber link 250 Once the line is broken, the return signal corresponding to (10) US 221-224 will disappear. It can be seen that if the ONUs 221-224 are classified into the same group 26〇, the fiber link corresponding to the group can be determined when all the signals of the 〇NUs in the group are in an unsteady range. Road 250 may have problems. The second C diagram shows a schematic diagram of another link-breaking situation in the passive optical network 200 of the second figure. In this example, a wire break occurs somewhere in the fiber link between the optical splitter 210 and the ONU 224. At this time, the reading unit 204 will detect the 0NU return optical power distribution map as shown in the third C diagram. Because the disconnection is the necessary route for the 0NU 224 to communicate with the optical line terminal device 202 (and the communication between the other toilets in the network and the optical fiber terminal device 202 is difficult to pass through the broken fiber link), the disconnection is broken. The signal corresponding to the message of 0NU 224 is bound to disappear. It can be seen that when the backhaul signal of the ONU 224 is in an abnormal range, it can be determined that the corresponding fiber link may have a problem. 13 200841616 It is not clear from the above that the present invention also proposes a fiber link monitoring method for a passive optical network. The fourth figure shows a passive optical network link monitoring method according to an embodiment of the present invention. The method can be applied to the second figure = the optical network architecture. The following description will refer to the number of the second figure. The fiber network link monitoring method shown in the fourth figure includes step 402_406. The steps are decremented to determine the plural group 26G_263 such that each group (10)-talk contains a portion of the plurality of fiber optic network units 22 236. For example, the description of the second f map determines the content of the group 26Q_263, respectively. All fiber-optic network units in the same group and the fiber-optic line terminal equipment 2G2 must communicate through the same-specific fiber link, and other network units and fiber-optic line terminal devices that are not in this group communicate with each other. There is no need to pass this specific fiber bond. In accordance with this principle, each group can correspond to a particular fiber link (e.g., in the second figure, the group 26 包含 containing the circle s 22 224 corresponds to the fiber link 250). The above group may also include " second optical splitters 210-216 as shown in the second figure to facilitate the description of the connection relationship with the corresponding specific fiber link. Step 404 connects each group to the first optical component 208 via its corresponding fiber link. Step 406: The fiber optic line terminal device 202 reads the backhaul optical signal or optical energy of the plurality of groups 260-263 to determine the fiber between the optical fiber line terminal device 2, the first optical splitter 208, and the plurality of groups 260 263. Link status. For details on how to determine the status of the fiber link, see the description in Figure 4A. 200841616 * FIG. 4A is a flow chart showing the judgment of the optical fiber link state of the passive optical network ^ fiber link monitoring method according to an embodiment of the present invention. The following description still refers to the number in the second figure. Step 410 checks whether the backhaul optical signals or optical energy of all the groups 260-263 are in an abnormal state. If all of them are in an abnormal state, step 410a is executed to notify the main fiber link 240 that the abnormal state is abnormal; otherwise, step 412 is continued. Step 412 checks if the return optical signal or light energy of one of the groups 260-263 is in an abnormal state. If they are all in an abnormal state, step 412a is executed to alarm that the fiber link between the specific group and the first optical splitter 208 is in an abnormal state; otherwise, step 414 is continued. In step 414, it is determined whether all the groups have been checked. If there are still unchecked groups, then return to step 412 to continue checking the next specific group; if the check is completed, proceed to step 416. Step 416 checks if the backhaul optical signal or optical energy of one of the particular fiber optic network units in group 260-263 is in an abnormal state. If it is in an abnormal state, step 416a is performed, and the fiber link directly connected to the specific fiber network unit is in an abnormal state; otherwise, step 418 is continued. Step 418 determines if all of the fiber optic network units have been checked. If there are unchecked fiber optic network units, then return to step 416 to continue checking the next particular fiber optic network unit; if the inspection is complete, the process ends. 15 200841616 The flow of the fourth and fourth A diagrams can be mastered by the central processing unit 206A in the sixth figure. It is determined whether the return optical signal or the optical energy is in an abnormal state according to the normal strength range of the return optical signal set by each fiber network unit respectively. The normal power intensity range of the optical fiber network unit may be different. 5 is a block diagram of a fiber optic network system 200A having a fiber optic link monitoring function, including a fiber optic line terminal device 202, a light energy extraction component 209, a monitoring module 206, and a second embodiment of the present invention. Optical splitters 208-216 and fiber optic network units 221-236. The optical energy extraction component 209 is coupled to the fiber optic line termination device 202 and the monitoring module 206 and to the optical splitter 208 via the fiber optic link 240. Optical splitter 208 is coupled to optical splitters 210, 212, 214, and 216 via fiber optic links 250, 252, 254, and 256, respectively. The four optical splitters 210-216 are connected to the optical network v unit (221-224, 225-228, 229- through fiber links (280-283, 284-287, 288-291, 292-295), respectively. 232, 233-236). The architecture is essentially a light energy extraction component 209 and a monitoring module 206 between the fiber optic line termination device 202 and the optical splitter 208 in a conventional architecture. In practice, the optical energy capture component 209 and the monitoring module 206 can be integrated into the same module or even integrated into the fiber optic line termination device 202. The optical energy extraction component 209 can be a module including a light splitter and an optical filter or a module including a light splitter and a split wave 16 200841616 multiplexer (WDM) However, it is not limited to this e. The optical energy capture component 209 can retrieve the communication optical signal energy from the fiber optic network elements 221-236 to the fiber optic line termination device 202 based on a time division multiplexing protocol and transmit it to the monitoring module 206 for further analysis. The function of the monitoring module 206 is to detect and analyze the light energy extracted by the light energy extraction element 209, the internal architecture of which is illustrated in more detail in the embodiment of the sixth figure. The monitoring module 206 analyzes the received fiber network unit and the backhaul signal in units of groups. The monitoring module 206 performs the necessary conversion and analysis of the optical energy extracted by the optical energy extraction component 209 based on the concept of mapping all fiber links in the network to a particular group as described above. When it is found that there is a problem in the communication between all the fiber network units in the same group and the fiber line terminal device 202, it is determined that the fiber link corresponding to the group may be in an abnormal state, and should be further inspected. For detailed monitoring methods, please refer to the description of the fourth and fourth and fourth embodiments. The sixth diagram shows a functional block diagram of a monitoring module 206 of the fifth embodiment in accordance with an embodiment of the present invention, which includes a central processing unit 206A and an optical power detecting component 206B. The optical power detecting component 206B may be an optical signal detecting and converting component including a photo diode, but is not limited thereto. Its function is to perform optical power detection functions, such as converting light energy into electronic signals for subsequent analysis. The central processing unit 206A can be 200841616 to be a general-purpose microprocessor for further analyzing the converted signal of the optical power detecting component 206B, and judging whether there is a fiber link disconnection or abnormal condition. . The sixth diagram also shows that the monitoring module 206 is coupled to the fiber optic line termination device 202 and the primary fiber optic link 240 of the passive fiber optic network via the optical energy extraction component 209. In practice, as described above, the optical energy extraction component 209 and the monitoring module 206 can be integrated into the same module, or even integrated into the optical fiber line terminal device 2 0 2 ^ to become the reading unit as shown in the second figure. The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention; all other equivalent changes or modifications which are not departing from the spirit of the invention should be included. Within the scope of the patent application. [Simple description of the diagram] The first figure shows a conventional tree-like passive optical network architecture. The second figure shows a fiber optic network system with fiber link monitoring functionality in accordance with an embodiment of the present invention. The second to second C diagrams illustrate a schematic diagram of various link breaks in the passive optical network of the second figure. The third figure shows the normal optical fiber peripheral unit back-return optical power distribution map. The third to third C-pictures respectively show the optical power distribution maps of the optical network units corresponding to the disconnection of the second to fourth C-pictures. 18 200841616 The fourth figure shows a passive fiber optic network optical fiber link monitoring method in accordance with an embodiment of the present invention. Figure 4A is a flow chart showing the determination of the state of the optical fiber link state of the passive optical fiber network fiber link monitoring method according to an embodiment of the present invention. The fifth figure shows a fiber optic network system having a fiber optic link monitoring function in accordance with another embodiment of the present invention. Figure 6 is a block diagram showing the function of the monitoring module of the fifth embodiment in accordance with an embodiment of the present invention. [Major component symbol description] 100 tree-type passive optical network architecture 102 optical fiber line terminal equipment 104, 106, 108, 110, 112 optical splitter 121-136 optical network unit (ONU) 200/200A with link monitoring function Passive optical network 202 optical fiber line terminal 204 reading unit 206 monitoring module 206A central processing unit 206B optical power detecting unit 208 first optical splitter 209 optical energy extracting component 19 200841616 210, 212, 214, 216 second Optical splitter 221-236 fiber optic network unit (0NU) 240 main fiber link 250, 252, 254, 256 260-263 group 280-295 fiber optic link fiber link 4 0 2 - 418 passive fiber optic network fiber chain Road monitoring method step 410a/412a/416a passive fiber optic network fiber link monitoring method alarm step 20