JP3602049B2

JP3602049B2 - ATM-PON dynamic bandwidth control method and system

Info

Publication number: JP3602049B2
Application number: JP2000330829A
Authority: JP
Inventors: 源一郎関根
Original assignee: NEC Communication Systems Ltd
Current assignee: NEC Communication Systems Ltd
Priority date: 2000-10-30
Filing date: 2000-10-30
Publication date: 2004-12-15
Anticipated expiration: 2020-10-30
Also published as: JP2002141909A

Description

【０００１】
【発明の属する技術分野】
本発明は、ＡＴＭ（ＡｓｙｎｃｈｒｏｎｏｕｓＴｒａｎｓｆｅｒＭｏｄｅ）ネットワークシステムに関し、特に、ＡＴＭ−ＰＯＮ方式の動的帯域制御技術に関する。
【０００２】
【従来の技術】
ＡＴＭ−ＰＯＮ（ＰａｓｓｉｖｅＯｐｔｉｃａｌＮｅｔｗｏｒｋ）方式による伝送網は、経済的に家庭まで光化（ＦＴＴＨ：ＦｉｂｅｒＴｏＴｈｅＨｏｍｅ）することが可能な方式とされている。光化時に使用できる帯域を生かすサービスとして、インターネット接続がある。インターネット接続で使用されるデータは、ＩＰ（ｉｎｔｅｒｎｅｔｐｒｏｔｏｃｏｌ）パケットの形態であり、必要な瞬間だけデータが発生するような使用方法が一般的である。
【０００３】
ＡＴＭ−ＰＯＮ方式では、加入者から網方向の上り帯域は、固定で運用されているのが一般的である。
【０００４】
ＩＰデータのやり取りが主目的の使用環境では、使用帯域の事前予測が不可能であるため、使用帯域の申告による帯域設定を行っている。しかしながら、設定される帯域は、データの瞬間的な増大を考慮すると、非常に広い帯域を確保する必要があり、経済的でない。また、未使用時にも、固定的に帯域を確保しているため、伝送網全体では、効率的ではない。
【０００５】
したがって、経済的に家庭まで光化するためには、ＡＴＭ−ＰＯＮ方式のＡＴＭ伝送網において、ＩＰデータに特化した帯域制御方法が必要となる。
【０００６】
ＡＴＭ−ＰＯＮ方式のＡＴＭ伝送網における既存の帯域制御方法として、使用帯域の申告による固定設定がある。図４を参照して、ＡＴＭ−ＰＯＮ方式のＡＴＭ伝送網のシステム構成について、その概略を説明しておく。図４において、ＩＰ端末５ａ、５ｂ及び５ｃは、ＩＰ通信を行う端末である。
【０００７】
ＣＬＡＤ４ａ、４ｂ及び４ｃは、イーサネットインタフェースとＡＴＭインタフェースを持ち、ＩＰパケットとＡＴＭセルの相互変換を行うセル化デセル化（ｃｅｌｌａｓｓｅｍｂｌｙａｎｄｄｅａｓｓｅｍｂｌｙ）装置である。
【０００８】
光受動素子２ａ及び２ｂは、ＡＴＭ−ＰＯＮ方式に基づく光信号を光学的に結合する装置である。
【０００９】
ＡＴＭ−ＰＯＮ加入者側装置３ｂは、送信するＡＴＭセルを一時的に格納する送信バッファ３１０と、制御セルを生成送信する制御セル送信部３１２と、ＡＴＭ−ＰＯＮ方式の光信号の送信（光ファイバを介して光受動素子２ａに送信する）を行う加入者側光送信部３１１と、送信帯域の増加が必要な時に制御セルを用いて送信要求制御を行い割り当てられた送信タイミングに基づき送信制御を行う送信制御部３１３と、ＡＴＭ−ＰＯＮ方式の光信号の受信（光受動素子２ｂから光ファイバを介して送信された信号を受信する）を行う加入者側光受信部３２３と、受信したＡＴＭセルのうち制御セルを受信する制御セル受信部３２４と、受信すべきＶＰＩ（ＶｉｒｔｕａｌＰａｓｓＩｄｅｎｔｉｆｉｅｒ）番号を蓄える受信ＶＰＩテーブル３２２と、受信したＡＴＭセルのＶＰＩ番号と受信ＶＰＩテーブル３２２に保存されている値を比較し、一致した場合のＡＴＭセルを通過させる受信セルフィルタ部３２１と、受信したＡＴＭセルを一時的に格納する受信バッファ３２０と、から成る。ＡＴＭ−ＰＯＮ加入者側装置３ｃは、ＡＴＭ−ＰＯＮ加入者側装置３ｂと同様な装置である。
【００１０】
ＡＴＭ−ＰＯＮ網側装置１は、送信するＡＴＭセルを一時的に格納する送信バッファ１１３と、上り帯域を制御する上り帯域制御部１１２と、上り帯域に基づいた上り送信タイミングを組み込んだ制御セルを一定時間毎に生成する制御セル送信部１１１と、送信ＡＴＭセルと制御セルを足しあわせてＡＴＭ−ＰＯＮ方式の光信号送信を行う網側光送信部１１０と、ＡＴＭ−ＰＯＮ方式の光信号受信を行う網側光受信部１２０と、受信したＡＴＭセルを一時的に格納する受信バッファ１２１と、受信したＡＴＭセルのうち制御セルを受信する制御セル受信部１２２と、から成る。
【００１１】
【発明が解決しようとする課題】
上記した従来のシステムにおいて、網側装置１の上り帯域制御部１１２における上り帯域の設定は固定とされている。すなわち、加入者側装置の状態と網側からの帯域制御の連携等は存在しない。
【００１２】
上述のように、ＩＰデータのやり取りが主目的の使用環境では、固定で設定される帯域は、データの瞬間的な増大を考慮すると、非常に広い帯域を確保する必要があり、経済的でない。また、未使用時にも固定的に帯域を確保しているため、伝送網全体では、効率的ではなく、網を経済的に運用出来ないこと意味する。さらに、家庭での使用を考えた場合、使用料金は大きな問題であり、その算出根拠となる網の運用コストが、家庭までの光化普及への大きな課題となる。
【００１３】
そこで、本発明は、上記課題に鑑みて創案されたものであって、その目的は、ＡＴＭ−ＰＯＮ方式のＡＴＭ伝送網において、上り伝送路に対してデータ毎に必要な帯域を設定することで、実使用に見合った帯域設定を可能とし、経済的な網運用を可能とするシステム及び方法を提供することにある。
【００１４】
【課題を解決するための手段】
前記目的を達成する本発明は、ＡＴＭ−ＰＯＮ方式によるＡＴＭ伝送網システムにおいて、加入者側装置から送信された帯域要求用制御セルに基づき、網側装置が、前記加入者側装置から網側装置への伝送帯域の割り当てを動的に制御するものである。
【００１５】
【発明の実施の形態】
本発明の実施の形態について説明する。本発明は、ＡＴＭ−ＰＯＮ方式によるＡＴＭ伝送網において、加入者から網側への伝送帯域を動的に制御して、ＩＰデータを効率良く伝送するものである。
【００１６】
ＡＴＭ−ＰＯＮ（ＰａｓｓｉｖｅＯｐｔｉｃａｌＮｅｔｗｏｒｋ）方式は、光受動素子による結合で１つの網側装置と複数の加入者側装置を結ぶＡＴＭ伝送方式であり、その特徴の１つは、１つの網側装置を複数の加入者で共用することにあり、網側のコスト低減が可能とされ、加入者毎の実使用帯域に合わせた帯域制御を行うことで、経済的にＡＴＭ伝送網を構築することができる。
【００１７】
ＡＴＭ−ＰＯＮ方式では、網側から加入者側への下り伝送と、加入者側から網側への上り伝送とを、異なる光周波数を用いて行い、制御を分離して行っている。
【００１８】
網側から加入者側への下り伝送では、すべての加入者に、同一のＡＴＭセルを配信する。これを、加入者装置では、加入者毎に設定される自装置使用のＶＰＩ（ＶｉｒｔｕａｌＰａｓｓＩｄｅｎｔｉｆｉｅｒ）番号と、配信されるＡＴＭセルのＶＰＩ番号を比較し、一致したものを取り込む。
【００１９】
帯域制御は、網側からのＡＴＭセルの送出レートで制御しており、これは、一般的なＡＴＭ装置が持つトラフィック制御機能であるシェーピング技術で実現される。
【００２０】
加入者側装置から網側装置への上り伝送では、光受動素子で結合される加入者装置毎の光出力回路の発光タイミングを制御し、網側装置の光受信回路で、各加入者装置からのセルを、あたかも一つのセルデータ流として受信させる。
【００２１】
加入者側装置における発光タイミングの制御は、網側装置からの下り伝送セルに織り交ぜて配信される制御セルに含まれる発光制御信号を基準に行われる。
【００２２】
上り帯域制御は、網側装置が設定する発光間隔により制御される。従って、上り伝送の帯域制御は、網側装置で行われる。
【００２３】
図４を参照して説明したように、一般に、ＡＴＭ−ＰＯＮ方式の上り帯域制御は、使用帯域の申告、または事前の予測による固定帯域設定によって運用されている。
【００２４】
ここで、図２に示す構成のように、ＩＰデータのやり取りが主目的の使用環境の場合、使用帯域の事前予測が不可能であるため、使用帯域の申告による帯域設定を行っている。ここで設定される帯域は、データの瞬間的な増大を考慮すると、非常に広い帯域を確保する必要があり、経済的でない。また、未使用時にも固定的に帯域を確保しているため、伝送網全体では効率的ではない。
【００２５】
本発明は、図２に示す構成のＩＰデータのやり取りが主目的の使用環境において、実使用時にのみ帯域を割り振ることで、事前の申告による固定帯域設定を最小とし、また未使用時には、他の加入者に帯域を分配し、その結果、経済的、効率的な、ＡＴＭ−ＰＯＮ方式による伝送網を実現している。
【００２６】
図１は、本発明の実施の形態の動作原理を説明するための図である。ＩＰ端末５ｂからのＩＰパケットは、ＣＬＡＤ（セル組立・分解部）４ｂにて、複数のＡＴＭセルに分割されて、ＡＴＭ−ＰＯＮ加入者側装置３ｂの送信バッファ３１１にＡＴＭセルが格納される。
【００２７】
ここで、ＡＴＭ−ＰＯＮ網側装置１の上り帯域制御部１１２が決定する帯域に基づいた発光タイミング情報を格納した制御セルを、ＡＴＭ−ＰＯＮ網側装置１の制御セル送信部１１１が、一定周期で、ＡＴＭ−ＰＯＮ網側装置１から、加入者装置へのデータセルに織り交ぜて、網側光送信部１１０から、光受動素子２ｂを介して、接続されるすべてのＡＴＭ−ＰＯＮ加入者側装置に対して、送信する。
【００２８】
光受動素子２ｂを介して送信される、上記制御セルを含むＡＴＭセル流を、ＡＴＭ−ＰＯＮ加入者側装置の加入者側受信部３２３が受信し、データセルである場合には、受信ＶＰテーブル３２２のＶＰＩ値を参照して、当該セルのＶＰＩ値と一致した場合には、受信バッファ３２０に当該セルを格納する。
【００２９】
加入者側受信部３２３において、受信したセルが、制御セルである場合には、制御セル受信部３２４に送る。制御セル装置３２４は、制御セルから、発光タイミング情報を抜き出し、制御セル送信部３１２と送信制御部３１３に送る。
【００３０】
送信制御部３１３は、送信タイミング情報と、送信バッファ３１０の滞留しているセル量から判定し、どのＡＴＭ−ＰＯＮ加入者装置にも割り振られていないタイミングに帯域要求用制御セルを送出するように、制御セル送信部３１２に指示し、制御セル送信部３１２は、帯域要求用制御セルを生成し、加入者側光送信部３１１に送り、加入者側光送信部３１１は、帯域要求用制御セルを送出する。
【００３１】
ＡＴＭ−ＰＯＮ加入者側装置３ｂから送出された帯域要求用制御セルが、光受動素子２ａを経由して、ＡＴＭ−ＰＯＮ網側装置１の網側光受信部１２０に到着したとき、同様に、データを送りたい他のＡＴＭ−ＰＯＮ加入者側装置からの帯域要求様制御セルが同一タイミングで到着すると、データが破壊され、正常に受信出来ず、ＡＴＭ−ＰＯＮ網側装置１では、無視される。
【００３２】
ＡＴＭ−ＰＯＮ加入者側装置３ｂから送出された帯域要求用制御セルが、光受動素子２ａを経由して、ＡＴＭ−ＰＯＮ網側装置１の網側光受信部１２０に到着したときに、ＡＴＭ−ＰＯＮ加入者側装置３ｂ以外のＡＴＭ−ＰＯＮ加入者側装置からの帯域要求用制御セルが無い場合、ＡＴＭ−ＰＯＮ加入者収容装置３ｂからの帯域要求用制御セルは、ＡＴＭ−ＰＯＮ網側装置１の網側光受信部１２０で受信され、制御セル受信部１２２に送られ、制御セル受信部１２２では、帯域要求制御セル受信情報を、上り帯域制御部１１２に送る。
【００３３】
上り帯域制御部１１２は、１つのＩＰデータを送るために必要な最大セル長分だけ発光タイミング情報を追加し、発光タイミング情報を含む制御セルを、制御セル送信部１１１が一定周期で網側装置から加入者装置へのデータセルに織り交ぜて、網側光送信部１１０から、光受動素子２ｂを介して、すべてのＡＴＭ−ＰＯＮ加入者側装置に送信する。
【００３４】
上り帯域制御部１１２において、最大セル長分だけ発光タイミングの増加を終えたら、元の発光タイミング値に値を戻す。
【００３５】
ＡＴＭ−ＰＯＮ加入者側装置３ｂでは、帯域要求用制御セルを送出してから、予め定められた一定時間経過後にも、帯域が増加しない場合には、帯域要求用制御セルが、ＡＴＭ−ＰＯＮ網側装置１に未達か、他のＡＴＭ−ＰＯＮ加入者側装置からの制御セルとの衝突状態と判断し、不定期の時間だけ待ち、再度、要求用制御セルを送出する。要求用制御セルの再送制御により、上り伝送路の帯域が増加し（いますぐ増加しない場合でも、確率的にいつかは増加する）、ＩＰパケットが送出される。
【００３６】
このようにして、ＡＴＭ−ＰＯＮ方式によるＡＴＭ伝送網において、加入者から網側への伝送帯域を動的に制御して、ＩＰデータを効率良く伝送することができる。
【００３７】
【実施例】
上記した本発明の実施の形態についてさらに詳細に説明すべく、本発明の実施例について図面を参照して以下に説明する。図１は、本発明の一実施例の構成を示す図であり、ＡＴＭ−ＰＯＮ方式のＡＴＭ伝送網の構成の一例と、網側装置、加入者側装置の内部構成が示されている。
【００３８】
図１を参照すると、ＩＰ端末５ａ、５ｂ及び５ｃは、ＩＰ通信を行う端末である。ＣＬＡＤ４ａ、４ｂ及び４ｃは、イーサネットインタフェースとＡＴＭインタフェースを持ち、相互変換を行うセル化デセル化装置である。
【００３９】
ＡＴＭ−ＰＯＮ加入者側装置３ｂは、送信するＡＴＭセルを一時的に格納する送信バッファ３１０と、制御セルを生成送信する制御セル送信部３１２と、ＡＴＭ−ＰＯＮ方式の光信号の送信（光ファイバを介して光受動素子２ａに送信する）を行う加入者側光送信部３１１と、送信帯域の増加が必要な時に制御セルを用いて送信要求制御を行い割り当てられた送信タイミングに基づき送信制御を行う送信制御部３１３と、ＡＴＭ−ＰＯＮ方式の光信号の受信（光受動素子２ｂから光ファイバを介して送信された信号の受信）を行う加入者側光受信部３２３と、受信したＡＴＭセルのうち制御セルを受信する制御セル受信部３２４と、受信すべきＶＰＩ番号を蓄える受信ＶＰＩテーブル３２２と、受信したＡＴＭセルのＶＰＩ番号と受信ＶＰＩテーブル３２２に保存されている値を比較して一致した場合のＡＴＭセルを通過させる受信セルフィルタ部３２１と、受信したＡＴＭセルを一時的に格納する受信バッファ３２０と、を備えている。ＡＴＭ−ＰＯＮ加入者側装置３ｃは、ＡＴＭ−ＰＯＮ加入者側装置３ｂと同様な装置である。
【００４０】
ＡＴＭ−ＰＯＮ網側装置１は、送信するＡＴＭセルを一時的に格納する送信バッファ１１３と、予め設定される上り帯域に各ＡＴＭ−ＰＯＮ加入者側装置からの帯域要求を付加して新たな設定帯域を決定する上り帯域制御部１１２と、決定された上り帯域に基づいた上り送信タイミングを組み込んだ制御セルを一定時間毎に生成する制御セル送信部１１１と、送信ＡＴＭセルと制御セルを足しあわせてＡＴＭ−ＰＯＮ方式の光信号送信を行う網側光送信部１１０と、ＡＴＭ−ＰＯＮ方式の光信号受信を行う網側光受信部１２０と、受信したＡＴＭセルを一時的に格納する受信バッファ１２１と、受信したＡＴＭセルのうち制御セルを受信する制御セル受信部１２２と、から成る。
【００４１】
光受動素子２ａ及び２ｂは、ＡＴＭ−ＰＯＮ方式に基づく光信号を光学的に結合する装置である。
【００４２】
図２は、本発明の一実施例のシステム構成を示す図である。ＩＰ端末５ａ、５ｂ及び５ｃは、ＩＰ通信を行う端末である。ＣＬＡＤ４ａ、４ｂ及び４ｃは、セル化デセル化装置である。ＡＴＭ−ＰＯＮ加入者側装置３ｂ及び３ｃは、ＡＴＭ−ＰＯＮ方式によるＡＴＭ処理をする加入者側装置である。光受動素子２は、ＡＴＭ−ＰＯＮ方式に基づく光信号を光学的に結合する装置である。ＡＴＭ−ＰＯＮ網側装置１は、ＡＴＭ−ＰＯＮ方式によるＡＴＭ処理をする網側装置である。ＩＰ網６は、複数のＩＰ端末の集りよりなる網である。
【００４３】
図３は、本発明の実施例の動作を説明するための図であり、上り帯域増加のシーケンスが示されている。図３において、セルａ４０２〜セルｇ４１０は、データ用ＡＴＭセルである。ＯＡＭ４０１は、発光タイミング指示用の制御セルである。ＲＥＱ４０４は、帯域要求用の制御セルである。
【００４４】
▲１▼は、フレームｎの発光タイミング情報受信タイミングである。
【００４５】
▲２▼は、フレームｎ＋１の発光タイミング情報受信タイミングである。
【００４６】
▲３▼は、送信バッファにデータセルが滞留したことを通知する信号である。
【００４７】
▲４▼は、帯域要求用セルの生成の命令である（ＡＴＭ−ＰＯＮ加入者側装置における送信制御部３１３から制御セル送信部３１２への命令）。
【００４８】
▲５▼は、帯域要求用セルを受信し、帯域を増加させた発光タイミング情報の生成の命令である（網側装置１における上り帯域制御部１１２から制御セル送信部１１１への命令）。
【００４９】
▲６▼は、フレームｎ＋２の発光タイミング情報受信タイミングである。
【００５０】
▲７▼は、フレームｎ＋３の発光タイミング情報受信タイミングである。
【００５１】
図１において、ＩＰ端末５ｂから網側のＩＰ端末５ａにＩＰパケットを用いた通信を行う場合があるとする。
【００５２】
ＩＰ端末５ｂからのＩＰパケットは、ＣＬＡＤ４ｂにおいて、複数のＡＴＭセルにセル化されて、ＡＴＭ−ＰＯＮ加入者側装置３ｂに送られる。
【００５３】
ＡＴＭ−ＰＯＮ加入者側装置３ｂにおいて、まず、送信バッファ３１１にＡＴＭセルが格納される。
【００５４】
ＡＴＭ−ＰＯＮ網側装置１の上り帯域制御部１１２が決定する帯域に基づいた発光タイミング情報を格納した制御セル（図３のＯＡＭ（ＯｐｅｒａｔｉｏｎＡｎｄＭａｎａｇｅｍｅｎｔ）セル４０１）を、制御セル送信部１１１が、一定周期で、網側装置から加入者装置へのデータセルに織り交ぜて、網側光送信部１１０から、光受動素子２ｂを介して接続されるすべてのＡＴＭ−ＰＯＮ加入者側装置に送信する。
【００５５】
ＡＴＭ−ＰＯＮ加入者側装置３ｂにおいて、ＯＡＭセルを含むＡＴＭセル流を、加入者側受信部３２３が受信し、データセルである場合には、受信ＶＰＩテーブル３２２のＶＰＩ値を参照して、受信セルのＶＰＩ値と一致した場合には、受信バッファ３２０にセルを格納する。制御セル（ＯＡＭセル）である場合には、制御セル受信部３２４に送る。制御セル装置３２４は、制御セルから発光タイミング情報を抜き出し、制御セル送信部３１２と送信制御部３１３に送る。
【００５６】
ＡＴＭ−ＰＯＮ加入者側装置３ｂの送信制御部３１３は、送信タイミング情報と、送信バッファ３１０に滞留しているセル量から判定し、送信バッファにデータセルが滞留している場合（図３の例では、送信バッファにｂ〜ｇが滞留している）、どのＡＴＭ−ＰＯＮ加入者装置にも割り振られていない送信タイミングに、帯域要求用制御セル（ＲＥＱ）を送出するように、制御セル送信部３１２に指示する。
【００５７】
ＡＴＭ−ＰＯＮ加入者側装置３ｂの制御セル送信部３１２は、帯域要求用制御セル（ＲＥＱ）を生成し、加入者側光送信部３１１に送り、加入者側光送信部３１１は、帯域要求用制御セル（ＲＥＱ）４０４を送出する。
【００５８】
帯域要求用制御セル（ＲＥＱ）４０４が光受動素子２ａを経由し、ＡＴＭ−ＰＯＮ網側装置１の網側光受信部１２０に到着したとき、同様に、データを送りたい他のＡＴＭ−ＰＯＮ加入者側装置からの帯域要求様制御セルが同一タイミングで到着すると、データが破壊され、正常に受信出来ず、ＡＴＭ−ＰＯＮ網側装置１では無視される。一方、他のＡＴＭ−ＰＯＮ加入者側装置からの帯域要求用制御セルが無い場合、ＡＴＭ−ＰＯＮ加入者収容装置３ｂからの帯域要求用制御セルは、正常に、ＡＴＭ−ＰＯＮ網側装置１の網側光受信部１２０で受信され、制御セル受信部１２２に送られる。
【００５９】
ＡＴＭ−ＰＯＮ網側装置１の制御セル受信部１２２は、帯域要求制御セルの受信情報を、上り帯域制御部１１２に送り、上り帯域制御部１１２は、１つのＩＰデータを送るために必要な最大セル長分だけ、発光タイミング情報を追加し、制御セル（ＯＡＭ）を、制御セル送信部１１１が一定周期で網側装置から加入者装置へのデータセルに織り交ぜて、網側光送信部１１０から、光受動素子２ｂを介して、制御セル（ＯＡＭ）４０５をすべてのＡＴＭ−ＰＯＮ加入者側装置に送信する。
【００６０】
ＡＴＭ−ＰＯＮ網側装置１の上り帯域制御部１１２は、最大セル長分発光タイミングを増加し終えたら、元の発光タイミング値（初期値）にその値を戻す管理を行う。
【００６１】
ＡＴＭ−ＰＯＮ加入者側装置３ｂでは、帯域要求用制御セル（ＲＥＱ）を送出してから、一定時間後にも帯域が増加しない場合には、帯域要求用制御セルが、ＡＴＭ−ＰＯＮ網側装置１に未達か、他のＡＴＭ−ＰＯＮ加入者側装置からの制御セルとの衝突状態と判断し、不定期の時間だけ待ち、再度要求用制御セルを送出する。確率的にいつかは帯域が増加し、ＩＰパケットは送出される。
【００６２】
正常に受信したＡＴＭセルデータは、ＣＬＡＤ４ａに送られ、デセル化されてＩＰパケットとして、ＩＰ端末５ａに送られる。ＩＰ端末５ａからＩＰ端末５ｂへの通信は、現在のＡＴＭ−ＰＯＮ方式の通りである。
【００６３】
上述した実施例において、一度の帯域要求用制御セルの受信時に割り当てる増加帯域を固定ではなく、過去の割り振り帯域の履歴を参考にして、適時、可変させることにより、より効率的に運用できる。
【００６４】
【発明の効果】
以上説明したように、本発明によれば、ＩＰデータのやり取りが主目的の使用環境において、ＡＴＭ−ＰＯＮ方式を使用する場合に、実使用時のみ帯域を割り振ることで、事前の申告による固定帯域設定を最小として、未使用時には、他の加入者に帯域を分配することで、経済的、効率的なＡＴＭ−ＰＯＮ方式による伝送網を実現することができる、という効果を奏する。
【図面の簡単な説明】
【図１】本発明の一実施例の構成を示す図である。
【図２】本発明の一実施例のシステム構成を示す図である。
【図３】本発明の一実施例の動作シーケンスを示す図である。
【図４】従来のＡＴＭ−ＰＯＮ方式のＡＴＭ伝送網の構成を示す図である。
【符号の説明】
１ＡＴＭ−ＰＯＮ網側装置
２ａ、２ｂ光受動素子
３ｂ、３ｃＡＴＭ−ＰＯＮ加入者側装置
４ａ、４ｂ、４ｃＣＬＡＤ（セル化デセル化装置）
５ａ、５ｂ、５ｃＩＰ端末
１１０網側光送信部
１１１制御セル送信部
１１２上り帯域制御部
１１３送信バッファ
１２０網側光受信部
１２１受信バッファ
１２２制御セル受信部
３１０送信バッファ
３１１加入者側光送信部
３１２制御セル送信部
３１３送信制御部
３２０受信バッファ
３２１受信セルフィルタ部
３２２受信ＶＰＩテーブル
３２３加入者側光受信部
３２４制御セル受信部
４０１、４０５、４１１制御セル（ＯＡＭ）
４０２、４０３、４０６〜４１０データセル
４０４制御セル（ＲＥＱ）[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an ATM (Asynchronous Transfer Mode) network system, and more particularly to an ATM-PON dynamic bandwidth control technique.
[0002]
[Prior art]
A transmission network based on the ATM-PON (Passive Optical Network) system is a system that can economically convert to a home (FTTH: Fiber To The Home). There is an Internet connection as a service that makes use of the bandwidth that can be used at the time of lightening. The data used in the Internet connection is in the form of an IP (Internet protocol) packet, and is generally used in such a manner that data is generated only at the required moment.
[0003]
In the ATM-PON system, the upstream band from the subscriber to the network is generally operated in a fixed manner.
[0004]
In a usage environment where the exchange of IP data is the main purpose, it is impossible to predict the used bandwidth in advance, so the bandwidth is set by reporting the used bandwidth. However, in consideration of the instantaneous increase of data, it is necessary to secure a very wide band for the set band, which is not economical. In addition, even when unused, the bandwidth is fixedly secured, so that the entire transmission network is not efficient.
[0005]
Therefore, in order to economically switch to homes, a band control method specialized for IP data is required in an ATM-PON ATM transmission network.
[0006]
As an existing band control method in the ATM-PON ATM transmission network, there is a fixed setting by declaring a used band. An outline of the system configuration of the ATM-PON ATM transmission network will be described with reference to FIG. In FIG. 4, IP terminals 5a, 5b and 5c are terminals that perform IP communication.
[0007]
The CLADs 4a, 4b, and 4c are cell assembly and deassembly devices that have an Ethernet interface and an ATM interface and perform mutual conversion between IP packets and ATM cells.
[0008]
The optical passive elements 2a and 2b are devices for optically coupling optical signals based on the ATM-PON system.
[0009]
The ATM-PON subscriber unit 3b includes a transmission buffer 310 for temporarily storing ATM cells to be transmitted, a control cell transmission unit 312 for generating and transmitting control cells, and transmission of optical signals of the ATM-PON system (optical fiber And a transmission request control using a control cell when the transmission band needs to be increased, and performs transmission control based on the assigned transmission timing. A transmission control unit 313, a subscriber-side optical receiving unit 323 for receiving an optical signal of the ATM-PON system (receiving a signal transmitted from the optical passive element 2b via an optical fiber), and a received ATM cell. Control cell receiving section 324 for receiving a control cell, and a reception VPI table for storing a VPI (Virtual Pass Identifier) number to be received 22, the received cell is compared with the VPI number of the received ATM cell and the value stored in the received VPI table 322, and the received cell is temporarily stored when the received cell is matched. And a receiving buffer 320. The ATM-PON subscriber-side device 3c is similar to the ATM-PON subscriber-side device 3b.
[0010]
The ATM-PON network side device 1 includes a transmission buffer 113 for temporarily storing an ATM cell to be transmitted, an upstream band control unit 112 for controlling the upstream band, and a control cell incorporating the upstream transmission timing based on the upstream band. A control cell transmitting unit 111 which generates the optical signal at regular time intervals, a network side optical transmitting unit 110 which performs transmission of the optical signal of the ATM-PON system by adding the transmission ATM cell and the control cell, and receives an optical signal of the ATM-PON system. It comprises a network-side optical receiving unit 120, a receiving buffer 121 for temporarily storing received ATM cells, and a control cell receiving unit 122 for receiving control cells among the received ATM cells.
[0011]
[Problems to be solved by the invention]
In the above-described conventional system, the setting of the upstream band in the upstream band control unit 112 of the network device 1 is fixed. That is, there is no coordination between the state of the subscriber-side device and the band control from the network side.
[0012]
As described above, in a usage environment where the exchange of IP data is the main purpose, a fixedly set band needs to secure a very wide band in consideration of an instantaneous increase in data, and is not economical. Further, since the band is fixedly secured even when not in use, the entire transmission network is not efficient, meaning that the network cannot be operated economically. Furthermore, when considering use at home, the usage fee is a major problem, and the operating cost of the network, which is the basis for the calculation, is a major issue for the spread of light to the home.
[0013]
Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to set a necessary band for each data on an uplink transmission line in an ATM transmission network of an ATM-PON system. Another object of the present invention is to provide a system and a method capable of setting a bandwidth suitable for actual use and enabling economical network operation.
[0014]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides an ATM transmission network system based on the ATM-PON system, wherein a network-side device is transmitted from a subscriber-side device to a network-side device based on a band request control cell transmitted from the subscriber-side device. This dynamically controls the allocation of the transmission band to the network.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described. The present invention dynamically controls a transmission band from a subscriber to a network side in an ATM transmission network based on the ATM-PON system, thereby efficiently transmitting IP data.
[0016]
The ATM-PON (Passive Optical Network) system is an ATM transmission system in which one network-side device and a plurality of subscriber-side devices are connected by coupling by an optical passive element. Since it is shared by a plurality of subscribers, the cost on the network side can be reduced, and an ATM transmission network can be constructed economically by performing bandwidth control according to the bandwidth actually used for each subscriber. .
[0017]
In the ATM-PON system, downstream transmission from the network side to the subscriber side and upstream transmission from the subscriber side to the network side are performed using different optical frequencies, and control is performed separately.
[0018]
In downstream transmission from the network side to the subscriber side, the same ATM cell is delivered to all subscribers. The subscriber device compares the VPI (Virtual Pass Identifier) number used by the own device, which is set for each subscriber, with the VPI number of the ATM cell to be distributed, and fetches a match.
[0019]
Bandwidth control is performed by controlling the ATM cell transmission rate from the network side, and this is realized by a shaping technique which is a traffic control function of a general ATM device.
[0020]
In the upstream transmission from the subscriber unit to the network unit, the light emission timing of the optical output circuit of each subscriber unit connected by the optical passive element is controlled, and the optical reception circuit of the network unit transmits the signal from each subscriber unit. Are received as if they were one cell data stream.
[0021]
The control of the light emission timing in the subscriber side device is performed based on the light emission control signal included in the control cell distributed in a manner interwoven with the downstream transmission cell from the network side device.
[0022]
The upstream band control is controlled by the light emission interval set by the network device. Therefore, the band control of the upstream transmission is performed by the network side device.
[0023]
As described with reference to FIG. 4, generally, the upstream band control of the ATM-PON system is operated by declaring a band to be used or by setting a fixed band based on a prediction in advance.
[0024]
Here, as in the configuration shown in FIG. 2, in a usage environment where the exchange of IP data is the main purpose, it is impossible to predict the used bandwidth in advance, so the bandwidth is set by reporting the used bandwidth. The band set here is not economical because it is necessary to secure a very wide band in consideration of a momentary increase in data. Further, since the band is fixedly secured even when not in use, it is not efficient in the entire transmission network.
[0025]
According to the present invention, in a use environment where the exchange of IP data having the configuration shown in FIG. Bandwidth is distributed to subscribers, and as a result, an economical and efficient ATM-PON transmission network is realized.
[0026]
FIG. 1 is a diagram for explaining the operation principle of the embodiment of the present invention. The IP packet from the IP terminal 5b is divided into a plurality of ATM cells by a CLAD (cell assembling / disassembling unit) 4b, and the ATM cells are stored in the transmission buffer 311 of the ATM-PON subscriber unit 3b.
[0027]
Here, the control cell transmitting unit 111 of the ATM-PON network-side device 1 transmits the control cell storing the light emission timing information based on the band determined by the upstream band control unit 112 of the ATM-PON network-side device 1 to a predetermined period. Then, the data cells from the ATM-PON network-side device 1 to the subscriber device are interlaced, and all the ATM-PON subscribers connected from the network-side optical transmission unit 110 via the optical passive element 2b. Send to device.
[0028]
The ATM cell stream including the control cell transmitted through the optical passive element 2b is received by the subscriber-side receiving unit 323 of the ATM-PON subscriber-side device. Referring to the VPI value of H.322, if the value matches the VPI value of the cell, the cell is stored in the reception buffer 320.
[0029]
In the case where the received cell is a control cell in the subscriber side receiving section 323, it is sent to the control cell receiving section 324. The control cell device 324 extracts light emission timing information from the control cell and sends the information to the control cell transmitting unit 312 and the transmission control unit 313.
[0030]
The transmission control unit 313 determines from the transmission timing information and the amount of cells staying in the transmission buffer 310, and transmits the band request control cell at a timing not allocated to any ATM-PON subscriber unit. , The control cell transmitter 312 generates a band request control cell and sends it to the subscriber side optical transmitter 311. The subscriber side optical transmitter 311 generates a band request control cell. Is sent.
[0031]
Similarly, when the band request control cell transmitted from the ATM-PON subscriber-side device 3b arrives at the network-side optical receiver 120 of the ATM-PON network-side device 1 via the optical passive element 2a, When a band request control cell from another ATM-PON subscriber side device to which data is to be transmitted arrives at the same timing, the data is destroyed and cannot be received normally, and is ignored by the ATM-PON network side device 1. .
[0032]
When the band request control cell transmitted from the ATM-PON subscriber-side device 3b arrives at the network-side optical receiving unit 120 of the ATM-PON network-side device 1 via the optical passive element 2a, the ATM-PON is transmitted. If there is no band request control cell from the ATM-PON subscriber side device other than the PON subscriber side device 3b, the band request control cell from the ATM-PON subscriber accommodation device 3b becomes the ATM-PON network side device 1. Is received by the network-side optical receiving unit 120, and is sent to the control cell receiving unit 122. The control cell receiving unit 122 sends band request control cell reception information to the upstream band control unit 112.
[0033]
The upstream band control unit 112 adds the light emission timing information by the maximum cell length necessary for transmitting one piece of IP data, and transmits the control cell including the light emission timing information to the network-side device at a constant period. The data cell is transmitted to all ATM-PON subscriber side devices from the network side optical transmission unit 110 via the optical passive element 2b.
[0034]
When the upstream band control unit 112 finishes increasing the light emission timing by the maximum cell length, the value is returned to the original light emission timing value.
[0035]
In the ATM-PON subscriber-side device 3b, if the bandwidth does not increase even after a predetermined period of time has elapsed since the transmission of the bandwidth request control cell, the bandwidth request control cell is transmitted to the ATM-PON network. It determines that the local device 1 has not been reached or that it has collided with a control cell from another ATM-PON subscriber device, waits for an irregular period of time, and sends out the request control cell again. Due to the retransmission control of the request control cell, the bandwidth of the uplink transmission path increases (even if it does not increase immediately, it will increase at some point in probability), and an IP packet is transmitted.
[0036]
Thus, in the ATM transmission network based on the ATM-PON system, the transmission band from the subscriber to the network can be dynamically controlled, and the IP data can be transmitted efficiently.
[0037]
【Example】
Embodiments of the present invention will be described below in detail with reference to the drawings in order to explain the above-described embodiments of the present invention in further detail. FIG. 1 is a diagram showing a configuration of an embodiment of the present invention, showing an example of a configuration of an ATM transmission network of an ATM-PON system and an internal configuration of a network device and a subscriber device.
[0038]
Referring to FIG. 1, IP terminals 5a, 5b and 5c are terminals that perform IP communication. The CLADs 4a, 4b, and 4c are cellular decellularizers having an Ethernet interface and an ATM interface and performing mutual conversion.
[0039]
The ATM-PON subscriber unit 3b includes a transmission buffer 310 for temporarily storing ATM cells to be transmitted, a control cell transmission unit 312 for generating and transmitting control cells, and transmission of optical signals of the ATM-PON system (optical fiber And a transmission request control using a control cell when the transmission band needs to be increased, and performs transmission control based on the assigned transmission timing. A transmission control unit 313 for performing transmission, a subscriber-side optical reception unit 323 for receiving an optical signal of the ATM-PON system (reception of a signal transmitted from the optical passive element 2b via an optical fiber), Among them, a control cell receiving unit 324 for receiving a control cell, a reception VPI table 322 for storing a VPI number to be received, a VPI number of a received ATM cell and a reception VPI A reception cell filter section 321 which passes ATM cells when a match by comparing the value stored in Buru 322, a reception buffer 320 for storing the received ATM cells temporarily, and a. The ATM-PON subscriber-side device 3c is similar to the ATM-PON subscriber-side device 3b.
[0040]
The ATM-PON network side device 1 includes a transmission buffer 113 for temporarily storing ATM cells to be transmitted, and a new setting by adding a band request from each ATM-PON subscriber side device to a preset upstream band. An uplink bandwidth control unit 112 for determining a bandwidth, a control cell transmission unit 111 for generating a control cell incorporating an uplink transmission timing based on the determined uplink bandwidth at regular time intervals, and adding a transmission ATM cell and a control cell Network-side optical transmitter 110 for transmitting an ATM-PON optical signal, network-side optical receiver 120 for receiving an ATM-PON optical signal, and reception buffer 121 for temporarily storing received ATM cells. And a control cell receiving unit 122 for receiving a control cell among the received ATM cells.
[0041]
The optical passive elements 2a and 2b are devices for optically coupling optical signals based on the ATM-PON system.
[0042]
FIG. 2 is a diagram showing a system configuration according to one embodiment of the present invention. The IP terminals 5a, 5b and 5c are terminals that perform IP communication. The CLADs 4a, 4b, and 4c are cellular decelerating devices. The ATM-PON subscriber devices 3b and 3c are subscriber devices that perform ATM processing according to the ATM-PON method. The optical passive element 2 is a device that optically couples an optical signal based on the ATM-PON system. The ATM-PON network-side device 1 is a network-side device that performs ATM processing according to the ATM-PON method. The IP network 6 is a network including a group of a plurality of IP terminals.
[0043]
FIG. 3 is a diagram for explaining the operation of the embodiment of the present invention, and shows a sequence of increasing the upstream band. In FIG. 3, cells a402 to g410 are data ATM cells. The OAM 401 is a control cell for indicating a light emission timing. REQ 404 is a control cell for requesting a band.
[0044]
(1) is the light emission timing information reception timing of frame n.
[0045]
(2) is the light emission timing information reception timing of frame n + 1.
[0046]
{Circle around (3)} is a signal notifying that data cells have stayed in the transmission buffer.
[0047]
{Circle around (4)} is a command to generate a band request cell (command from the transmission control unit 313 to the control cell transmission unit 312 in the ATM-PON subscriber side device).
[0048]
{Circle around (5)} is a command for receiving the band requesting cell and generating the light emission timing information with the band increased (command from the upstream band control unit 112 to the control cell transmitting unit 111 in the network device 1).
[0049]
(6) is the light emission timing information reception timing of frame n + 2.
[0050]
{Circle around (7)} is the light emission timing information reception timing of frame n + 3.
[0051]
In FIG. 1, it is assumed that communication using an IP packet may be performed from the IP terminal 5b to the network-side IP terminal 5a.
[0052]
The IP packet from the IP terminal 5b is converted into a plurality of ATM cells in the CLAD 4b and sent to the ATM-PON subscriber side device 3b.
[0053]
In the ATM-PON subscriber-side device 3b, first, an ATM cell is stored in the transmission buffer 311.
[0054]
The control cell transmitting unit 111 transmits a control cell (OAM (Operation And Management) cell 401 in FIG. 3) storing light emission timing information based on the band determined by the upstream band control unit 112 of the ATM-PON network-side device 1. At regular intervals, data cells from the network side device to the subscriber device are interlaced and transmitted from the network side optical transmission section 110 to all ATM-PON subscriber side devices connected via the optical passive element 2b. .
[0055]
In the ATM-PON subscriber-side device 3b, the subscriber-side receiving unit 323 receives the ATM cell stream including the OAM cell, and if the ATM-PON is a data cell, receives the ATM cell flow by referring to the VPI value of the reception VPI table 322. If the value matches the VPI value of the cell, the cell is stored in the reception buffer 320. If it is a control cell (OAM cell), it is sent to the control cell receiver 324. The control cell device 324 extracts the light emission timing information from the control cell and sends the information to the control cell transmission unit 312 and the transmission control unit 313.
[0056]
The transmission control unit 313 of the ATM-PON subscriber-side device 3b determines from the transmission timing information and the amount of cells staying in the transmission buffer 310, and determines that the data cell is staying in the transmission buffer (the example in FIG. 3). Then, the control cell transmitting unit transmits the bandwidth request control cell (REQ) at a transmission timing not allocated to any ATM-PON subscriber device. Instruct 312.
[0057]
The control cell transmitter 312 of the ATM-PON subscriber unit 3b generates a band request control cell (REQ) and sends it to the subscriber optical transmitter 311. The control cell (REQ) 404 is transmitted.
[0058]
Similarly, when the band request control cell (REQ) 404 arrives at the network-side optical receiving unit 120 of the ATM-PON network-side device 1 via the optical passive element 2a, another ATM-PON to which data is to be transmitted is similarly added. When the bandwidth request control cell from the remote device arrives at the same timing, the data is destroyed, the data cannot be received normally, and is ignored by the ATM-PON network device 1. On the other hand, if there is no band request control cell from another ATM-PON subscriber side device, the band request control cell from the ATM-PON subscriber accommodating device 3b normally returns to the ATM-PON network side device 1. It is received by the network side optical receiving unit 120 and sent to the control cell receiving unit 122.
[0059]
The control cell receiving unit 122 of the ATM-PON network side device 1 sends the reception information of the band request control cell to the upstream band control unit 112, and the upstream band control unit 112 transmits the information required for transmitting one IP data. The light emission timing information is added by the length of the cell, and the control cell (OAM) interweaves the data cells from the network device to the subscriber device at regular intervals by the control cell transmitting unit 111, and the network side optical transmitting unit 110 Transmits the control cell (OAM) 405 to all ATM-PON subscriber side devices via the optical passive element 2b.
[0060]
When the upstream band control unit 112 of the ATM-PON network-side device 1 finishes increasing the light emission timing by the maximum cell length, it performs management to return the value to the original light emission timing value (initial value).
[0061]
The ATM-PON subscriber-side device 3b transmits the band request control cell (REQ), and if the band does not increase even after a certain period of time, the band request control cell becomes the ATM-PON network side device 1. , Or a collision state with a control cell from another ATM-PON subscriber side device, and waits for an irregular period of time, and sends out the request control cell again. Stochastically the bandwidth will increase sometime, and the IP packet will be sent out.
[0062]
The normally received ATM cell data is sent to the CLAD 4a, decellularized, and sent as an IP packet to the IP terminal 5a. The communication from the IP terminal 5a to the IP terminal 5b is according to the current ATM-PON system.
[0063]
In the above-described embodiment, it is possible to operate more efficiently by changing the time-varying band in a timely manner with reference to the history of the past allocated band instead of fixing the band to be allocated at the time of receiving the band request control cell once.
[0064]
【The invention's effect】
As described above, according to the present invention, when the ATM-PON system is used in a usage environment in which the exchange of IP data is the main purpose, the bandwidth is allocated only at the time of actual use. By minimizing the setting and distributing the band to other subscribers when not in use, it is possible to realize an economical and efficient ATM-PON transmission network.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of an embodiment of the present invention.
FIG. 2 is a diagram illustrating a system configuration according to an embodiment of the present invention.
FIG. 3 is a diagram showing an operation sequence of one embodiment of the present invention.
FIG. 4 is a diagram showing a configuration of a conventional ATM-PON type ATM transmission network.
[Explanation of symbols]
1 ATM-PON Network Side Devices 2a, 2b Optical Passive Devices 3b, 3c ATM-PON Subscriber Side Devices 4a, 4b, 4c CLAD (Cellular Decellularization Device)
5a, 5b, 5c IP terminal 110 Network-side optical transmitter 111 Control cell transmitter 112 Up-bandwidth controller 113 Transmission buffer 120 Network-side optical receiver 121 Receive buffer 122 Control cell receiver 310 Transmission buffer 311 Subscriber-side optical transmitter 312 Control cell transmitter 313 Transmission controller 320 Receive buffer 321 Receive cell filter 322 Receive VPI table 323 Subscriber side optical receiver 324 Control cell receiver 401, 405, 411 Control cell (OAM)
402, 403, 406-410 Data cell 404 Control cell (REQ)

Claims

One network-side device and a plurality of subscriber-side devices are connected by coupling by an optical passive element, and in the downstream transmission from the network-side device to the subscriber-side device, all the subscribers coupled by the optical passive element are connected. The same cell is delivered to the subscriber side device, and in the upstream transmission from the subscriber side device to the network side device, the light emission timing of each of the subscriber devices coupled by an optical passive element is controlled, In an ATM transmission network system configured to receive a cell transmitted from the side device to the upstream transmission path as a cell data stream in the network side device,
The subscriber unit, when transmitting data on the uplink transmission path, according to the amount of stagnation of transmission data, a control cell for bandwidth request, comprising means for transmitting to the network side device,
The ATM transmission network system according to claim 1, wherein said network-side device includes means for dynamically controlling allocation of an upstream transmission band based on a control cell for requesting a band from said subscriber-side device.

One network-side device and a plurality of subscriber-side devices are connected by coupling by an optical passive element, and in the downstream transmission from the network-side device to the subscriber-side device, all the subscribers coupled by the optical passive element are connected. The same cell is delivered to the subscriber side device, and in the upstream transmission from the subscriber side device to the network side device, the light emission timing of each of the subscriber devices coupled by an optical passive element is controlled, In an ATM transmission network system configured to receive a cell transmitted from the side device to the upstream transmission path as a cell data stream in the network side device,
The network device includes means for transmitting a control cell storing light emission timing information based on a band determined by an upstream band control unit to the subscriber device connected via the optical passive element,
The subscriber unit includes means for extracting light emission timing information from the control cell and transmitting a control cell for a band request,
The network-side device receives the control cell for the band request transmitted from the subscriber-side device, adds light emission timing information for a maximum cell length necessary for transmitting transmission data, and adds the light emission timing information. An ATM transmission network system, comprising: means for transmitting a control cell including the following to the subscriber unit connected via an optical passive element.

One network-side device and a plurality of subscriber-side devices are connected by coupling by an optical passive element, and in the downstream transmission from the network-side device to the subscriber-side device, all the subscribers coupled by the optical passive element are connected. The same cell is delivered to the subscriber side device, and in the upstream transmission from the subscriber side device to the network side device, the light emission timing of each of the subscriber devices coupled by an optical passive element is controlled to control the light emission timing of the subscriber side device. The network side device is configured to receive the cell transmitted from the device to the uplink transmission line as a cell data stream,
An ATM transmission network system in which the network-side device and one or a plurality of the subscriber-side devices are connected to an IP terminal via a cell-forming device for performing mutual conversion between IP packets and ATM cells. ,
The network device includes means for transmitting a control cell storing light emission timing information based on the band determined by the upstream band control unit to the subscriber device connected via the optical passive element,
The subscriber unit includes means for extracting light emission timing information from the control cell and transmitting a band request control cell,
In the network-side device, upon receiving a control cell for a band request transmitted from the subscriber-side device, the upstream band control unit controls the emission timing information by a maximum cell length necessary for transmitting IP packet data. And add
An ATM transmission network system comprising means for controlling a control cell including the updated light emission timing information to be transmitted from an optical transmission unit to the subscriber unit via an optical passive element.

2. The apparatus according to claim 1, wherein the subscriber unit transmits cell data obtained by converting IP packet data into ATM cells on an upstream transmission path from the subscriber unit to the network unit. Or the ATM transmission network system according to 2.

Allocating an uplink transmission band only when the subscriber unit uses an uplink transmission path, and setting a fixed bandwidth setting by advance declaration to a minimum value as an uplink transmission band managed by the network side device, The ATM transmission network system according to any one of claims 1 to 3 , wherein:

The ATM transmission network according to any one of claims 1 to 3 , wherein in the network-side device, after the light emission timing has been increased by the maximum cell length, the value is returned to the original set value of the light emission timing. system.

One network-side device and a plurality of subscriber-side devices are connected by coupling by an optical passive element, and in the downstream transmission from the network-side device to the subscriber-side device, all the subscribers coupled by the optical passive element are connected. The same cell is delivered to the subscriber side device, and in the upstream transmission from the subscriber side device to the network side device, the light emission timing of each of the subscriber devices coupled by an optical passive element is controlled to control the light emission timing of the subscriber side device. A bandwidth control method for an ATM transmission network, wherein a cell transmitted from an apparatus to an upstream transmission path is received as a cell data stream by the network side apparatus,
When the subscriber unit transmits data on an uplink transmission path from the subscriber unit to the network unit, a control cell for a bandwidth request is transmitted to the network unit according to the amount of transmission data. Transmitting a dynamic bandwidth control method for an ATM transmission network based on a control cell for requesting a bandwidth from the subscriber side apparatus. .

One network-side device and a plurality of subscriber-side devices are connected by coupling by an optical passive element, and in the downstream transmission from the network-side device to the subscriber-side device, all the subscribers coupled by the optical passive element are connected. The same cell is delivered to the subscriber side device, and in the upstream transmission from the subscriber side device to the network side device, the light emission timing of each of the subscriber devices coupled by an optical passive element is controlled to control the light emission timing of the subscriber side device. A bandwidth control method for an ATM transmission network, wherein a cell transmitted from an apparatus to an upstream transmission path is received as a cell data stream by the network side apparatus,
The network-side device transmits a control cell storing light emission timing information based on a band determined by an upstream band control unit to all the subscriber-side devices connected via the optical passive element,
The subscriber unit includes the steps of extracting the light emission timing information from the control cell, based on the retention amount of the transmission buffer, and sends the bandwidth request control cells,
The network-side device receives the band request control cell transmitted from the subscriber-side device, and adds light emission timing information for a maximum cell length necessary for transmitting transmission data, and updates the light emission timing information. Transmitting a control cell to the subscriber side device via the optical passive element, and
A dynamic bandwidth control method for an ATM transmission network, comprising:

One network-side device and a plurality of subscriber-side devices are connected by coupling by an optical passive element, and in the downstream transmission from the network-side device to the subscriber-side device, all the subscribers coupled by the optical passive element are connected. The same cell is delivered to the subscriber side device, and in the upstream transmission from the subscriber side device to the network side device, the light emission timing of each of the subscriber devices coupled by an optical passive element is controlled to control the light emission timing of the subscriber side device. The network side device is configured to receive the cell transmitted from the device to the uplink transmission line as a cell data stream,
A bandwidth control method for an ATM transmission network in which the network-side device and one or more subscriber-side devices are connected to an IP terminal via a cell-forming device for converting IP packets and ATM cells to and from each other. And
The network-side device transmits a control cell storing light emission timing information based on a band determined by an upstream band control unit to all the subscriber-side devices connected via the optical passive element,
The subscriber unit extracts the light emission timing information from the control cell, and sends a control cell for a band request in accordance with the amount of stay of transmission data,
The network-side device receives the control cell for bandwidth request transmitted from the subscriber-side device, adds the light-emission timing information for the maximum cell length necessary for transmitting the IP packet data, and updates the updated light-emission. Transmitting a control cell including timing information to the subscriber side device via the optical passive element;
A dynamic bandwidth control method for an ATM transmission network, comprising:

9. The method according to claim 7 , wherein the subscriber unit transmits cell data obtained by converting IP packet data into ATM cells on an upstream transmission path from the subscriber unit to the network unit. A dynamic bandwidth control method for an ATM transmission network according to the above.

Allocate an uplink transmission band only when using the uplink transmission path by the subscriber side device, set a fixed bandwidth setting by prior declaration to a minimum value, and distribute the band to other subscriber side devices when not in use, dynamic bandwidth control method of the ATM transmission network according to any one of claims 7 to 9, characterized in that.

Wherein the subscriber units, the uplink transmission path from the subscriber-side apparatus to the network device transmits the cell data obtained by converting the IP packet data into ATM cells, according to claim 7 to 9, characterized in that A dynamic bandwidth control method for an ATM transmission network according to any one of the preceding claims.

The ATM transmission network according to any one of claims 7 to 9 , wherein in the network side device, when the light emission timing has been increased by the maximum cell length, the value is returned to the original set value of the light emission timing. Dynamic bandwidth control method.