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WO2003073784A1 - Cross-connector for transmitting signals between an sdh/sonet network and an optical network - Google Patents

Cross-connector for transmitting signals between an sdh/sonet network and an optical network Download PDF

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Publication number
WO2003073784A1
WO2003073784A1 PCT/DE2003/000578 DE0300578W WO03073784A1 WO 2003073784 A1 WO2003073784 A1 WO 2003073784A1 DE 0300578 W DE0300578 W DE 0300578W WO 03073784 A1 WO03073784 A1 WO 03073784A1
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WO
WIPO (PCT)
Prior art keywords
otn
signals
switching matrix
stm
network
Prior art date
Application number
PCT/DE2003/000578
Other languages
German (de)
French (fr)
Inventor
Horst Müller
Original Assignee
Siemens Aktiengesellschaft
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Publication date
Application filed by Siemens Aktiengesellschaft filed Critical Siemens Aktiengesellschaft
Priority to AU2003214009A priority Critical patent/AU2003214009A1/en
Publication of WO2003073784A1 publication Critical patent/WO2003073784A1/en

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J3/00—Time-division multiplex systems
    • H04J3/16—Time-division multiplex systems in which the time allocation to individual channels within a transmission cycle is variable, e.g. to accommodate varying complexity of signals, to vary number of channels transmitted
    • H04J3/1605—Fixed allocated frame structures
    • H04J3/1652—Optical Transport Network [OTN]
    • H04J3/167—Optical Transport Network [OTN] interaction with SDH/SONET, e.g. carrying SDH/SONET frames, interfacing with SDH/SONET
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J3/00—Time-division multiplex systems
    • H04J3/16—Time-division multiplex systems in which the time allocation to individual channels within a transmission cycle is variable, e.g. to accommodate varying complexity of signals, to vary number of channels transmitted
    • H04J3/1605—Fixed allocated frame structures
    • H04J3/1611—Synchronous digital hierarchy [SDH] or SONET
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0005—Switch and router aspects
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0062—Network aspects
    • H04Q11/0071—Provisions for the electrical-optical layer interface
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0062—Network aspects
    • H04Q2011/0075—Wavelength grouping or hierarchical aspects

Definitions

  • Crossconnector for the transmission of signals between an SDH / SONET network and an optical network
  • the invention relates to a universal cross connector for signals of a network of the synchronous digital hierarchy and for signals of an optical transport network; it also concerns a universal cross connector only for signals of the optical transport network.
  • the regional transmission networks in Europe use transmission systems that operate according to the synchronous digital hierarchy, SDH, in accordance with ITU recommendation G.707.
  • SDH synchronous digital hierarchy
  • systems based on the SONET standard are used, which are also specified in ITU recommendation G.707.
  • These regional networks are mostly built up in ring structures, which in the synchronous digital hierarchy transmit bit rates of 155 Mbit / s for STM-1 signals, 622 Mbit / s for STM-4 signals, 2.5 Mbit / s for STM-16 signals up to 10 Gbit / s for STM-64 signals. Higher transmission rates are aimed for.
  • the useful signals transmitted in these networks are packaged in so-called virtual containers VC-n, with granularities of 2 Mbit / s for the virtual container VC-12, 34 Mbit / s for VC-3 and 140 Mbit / s for VC-4 containers SDH standard; with the SONET standard with granularities of 1.5 Mbit / s for VC-11, 6 Mbit / s for VC-2 and 45 Mbit / s for VC-3 containers.
  • cross connect systems cross-switching devices
  • cross-switching devices cross-switching devices
  • SDH / SONET signals with data rates of 2.5 Gbit / s, 10 Gbit / s and in na- ago 40 Gbit / s transport signals formed.
  • STM-16/64/256 higher-order SDH / SONET signals
  • FEC error correction
  • the granularity of the signals in the OTN is STM-16/64/256 or OTU-1/2/3, ie the smallest bit rate that can be switched in the OTN is 2.5 Gbit / s.
  • Optical cross connect systems for distributing the useful signals are also provided here.
  • a cross connector For the transition between the regional SDH / SONET network (hereinafter only referred to as the SDH network) and the national "optical network *", a cross connector should be specified that offers a high degree of flexibility and is inexpensive to implement.
  • switching through with a finer granularity should also be made possible in the optical transport network, which enables a finer granularity in the distribution of the useful signals.
  • a cross connector for the optical transport network is specified in independent claim 3.
  • the main advantage of the invention is achieved by two switching matrixes and converters.
  • OTN line connections are connected to connections of an OTN switching matrix and SDH line connections to an SDH switching matrix.
  • These switching networks can switch through OTN signals or SDH signals.
  • the converters enable switching operations between SDH and OTN data formats.
  • OTN switching matrix signals can be switched with an SDH granularity. Since converters are only used when needed, this solution is particularly cost-effective.
  • FIG. 1 shows an SDH / SONET network and an OTN network with cross connect devices
  • FIG. 2 shows a universal cross connector
  • FIG. 3 shows a variant with several OTN switching matrix signals
  • FIG. 4 shows a simplified cross connector for STM-16 signals
  • FIG. 5 shows a simplified cross connector for ODU-1 signals
  • FIG. 6 shows an OTN cross connector
  • FIG. 7 shows an expanded OTN cross connector.
  • Figure 8 shows the frame structure of an STM-N signal and VC-4 container and Figure 9 shows the frame structure of an ODU / OTU signal.
  • FIG. 1 shows an SDH / SONET network SDH-N with a plurality of ring networks STM-4-N, STM-16-N of different data rates, each of which has a number of add / drop multiplexers ADM. These networks are connected via a cross connector CC-SO to an optical transport network OTN which has a plurality of optical network elements ONE and further cross connectors CC-S02, CC-S03 and an OTN cross connector CC-0.
  • the Crossconnector CC-SO enables flexible interconnection of SDH / SONET signals STM-N in the SDH network as well as flexible interconnection of optical transport signals of the OTN network and also serves as a connection between the two networks.
  • the cross connector CC-SO is an object of this invention.
  • the principle on which this invention is based was also used in the OTN Crossconnector CC-0 in order to convert and distribute different data formats of the optical transport network OTN into one another.
  • FIG. 2 shows a symbolic representation of the cross connector CC-SO.
  • This contains two coupling fields VC-KF and OTN-TKF, which correspond to one another via converter devices U10, Uli, U21, for different data formats and with connection circuits that connect the cross-connector to both networks.
  • the first switching matrix VC-KF is designed for signals of a synchronous digital hierarchy STM-N and is referred to below as a VC switching matrix.
  • the signal names are also limited to SDH signals, although the switching matrix can also be designed for SONET signals.
  • the transport signals (transport modules) STM-N are received and sent at the SDH connections (inputs and outputs) AS1 to ASm.
  • Port switches PS1 to PSm are connected to switching network connections (inputs and outputs), which process the received STM transport signals in accordance with the ITU recommendations, i.e. that the regenerator and multiplexer section overhead, RSOH and MSOH are terminated and the useful signals in the form can be recovered from virtual containers VC-4 at SDH (or VC-3 at SONET).
  • FIG. 8 The format of the STM-N transport modules and the container VC-4 contained therein by N is shown in FIG. 8 and corresponds to FIG. 8-8, ITU recommendation G.707, 03/1996.
  • a repositioning of the useful signals is also required in order to adapt them to the clock rate of the cross connector CC-SO. This is understood to mean that the pointer of the incoming signal, which points to the first byte of the virtual container, is recalculated in accordance with the phase and frequency of the frame clock of the SDH switching matrix.
  • the signals treated in this way are routed to the VC switching matrix as switching matrix signals ISDH.
  • the internal switching matrix signals ISDH preferably have an SDH-like structure, but do not include, for example, the regenerator and section overhead. They correspond approximately to the VC-4 container, possibly supplemented by internal switching matrix information.
  • FIG. 2 is therefore to be understood as a basic circuit diagram for both transmission directions, in which signals are both received and transmitted at the connections AS1 to ASn. This form of presentation is also used in the ITU recommendations.
  • the VC switching matrix VC-KF initially enables the free interconnection (cross-connection) of individual electrical switching signals ISDH assigned to specific containers between any port switching and thus between any SDH connections AS1 to ASm.
  • the VC switching matrix is now logically (i.e. directly or via the OTN switching matrix) connected to the OTN switching matrix via the converter devices U10, Uli, U21.
  • this is implemented as a transparent switching network OTN-TKF, since it has to switch through different formats of OTN switching network signals, for example ODU-1 (Optical Data Unit) and STM-16, in electrical form.
  • ODU-1 Optical Data Unit
  • STM-16 in electrical form.
  • These signals have been obtained, for example, from optical transport signals OTU-1, OTU-2 by demultiplexing and, if appropriate, conversion into another data format or have been transmitted via a separate channel.
  • the OTN switching matrix signals can also contain additional internal switching matrix information.
  • the OTN switching matrix signals can also be distributed directly or after conversion to another OTN data format, for example OTU-1 in STM-16, in the OTN switching matrix and forwarded via different OTN connections AOl to A04 in the optical transport network. However, they can also be switched through to the VC switching matrix VC-KF via conversion devices U10 and Uli.
  • OTN data format for example OTU-1 in STM-16
  • OTN switching matrix VC-KF via conversion devices U10 and Uli.
  • the U10 converter function consists in one direction of an ISDH signal bundle coming from the VC switching matrix, consisting of 16 VC-4 or 48 VC-3 signals, adding the the required overheads RSOH and MSOH to a STM-16 signal, which can then be switched through in the transparent OTN switching matrix and thus creates a connection between the SDH network and the OTN.
  • STM-16 signals coming from the optical transport network OTN are terminated in the converter UlO; the 16 VC-4 or 48 VC-3 signals are adapted to the clock rate of the VC switching matrix VC-TKF by repointering, thus in VC switching matrix signals ISDH implemented to access the SDH network via the VC switching network.
  • the converter device Uli has the task of initially supplementing an ISDH signal bundle in one direction by adding 0-threads RSOH and MSOH to an STM-16 signal.
  • an ODU-1 signal is formed which can be switched through in the OTN switching matrix (FIG. 9).
  • the ODU-1 signal is first terminated in the Uli converter and the recovered STM-16 signal is further processed, as in the UlO converter, to form an ISDH switching matrix signal.
  • the interaction of the two switching matrixes also enables switching of OTN signals with VC-4/3 granularity by passing an OTN switching matrix signal over a converter and the VC switching matrix and then converting it into an OTN switching matrix signal via this converter or another converter is supplied to the OTN network.
  • the converter device U21 makes it possible to connect different OTN switching matrix signals ODU-1 and STM-16 through the transparent OTN switching matrix and to convert them into one another.
  • This implementation can also take place via the two conversion devices UlO and Uli.
  • the U21 converter function is, in one direction, an STM-16 signal by adding overheads to an ODU-1 Implement signal that can be interconnected in the transparent OTN switching matrix OTN-TKF.
  • the ODU-1 signal is terminated in the opposite direction and the recovered STM-16 signal can be connected again in the transparent switching matrix.
  • the network connection circuits NAH to NA2n connected to the OTN switching matrix are also provided for converting data formats.
  • the network connection circuits NAll-NAln each convert ODU-1 signals into optical channel transport units OTU-1 signals in the transmission direction.
  • an OTU 0 head OTU-OH and an OTU forward error correction section OTU-FEC are added to the ODU-1 signal.
  • FIG. 9 shows the pulse frame including the overhead of an OTU-1 signal.
  • the network connection circuits NAH-NAln By means of an electrical / optical conversion, the network connection circuits NAH-NAln generate optical signals with specific wavelengths ⁇ l to ⁇ n, which are combined in a wavelength division multiplexing device Wl to form an “Optical Transport Module * Signal OTM-1 and transmitted.
  • the wavelength multiplex signal is first split in the receiving direction. Then an error correction is carried out in each case in the network connection circuits; the OTU overhead OTU-OH is terminated and ODU-1 signals with wavelengths ⁇ l to ⁇ n are recovered from OTU-1 signals.
  • the mains connection circuits NA21 to NA2n have additional multiplex and demultiplex devices with which 4 ODU-1 signals are combined to form an ODU-2 signal in the transmission direction. A corresponding overhead and corresponding correction bytes are added to the 4 ODU-1 signals. After an electrical / optical conversion, the optical output signals of the mains connection circuits are Optical Transport Module Signal OTM-2. In the receiving direction, signals with wavelengths ⁇ l to ⁇ n are again obtained from the OTM-2 signal and ODU-1 signals are obtained in the network connection circuits after error correction and termination.
  • multiplexing 4 ODU-1 signals into one OTU-2 signal instead of multiplexing 4 ODU-1 signals into one OTU-2 signal, multiplexing and of 16 ODU-1 signals into one OTU-3 signal can of course also be provided.
  • the transponders TR1 to TRn each convert an electrical STM-16 signal into an optical signal with a specific wavelength ⁇ l to ⁇ n in the transmission direction.
  • the optical signals are combined in a wavelength multiplexing device W3 to form a WDM signal WDM-1.
  • individual signals with wavelengths ⁇ l to ⁇ n are obtained from the signal WDM-1 by filters and converted back into electrical STM-16 signals in a transponder.
  • multiplex devices MUX1 to MUXn are provided as network connection circuits, each of which combines 4 STM-16 signals in the transmission direction to form an optical STM-64 signal with specific wavelengths ⁇ l to ⁇ n.
  • the STM-64 signals are multiplexed in a wavelength multiplexing device W4 to form a signal WDM-2.
  • a received WDM-2 signal is divided into individual signals ⁇ l to ⁇ n and divided into electrical STM-16 signals in the multiplexing devices MUX1 to MUXn.
  • multiplexing of 16 STM-16 signals into one STM-256 signal etc. can of course also be provided by appropriately designed multiplex devices.
  • the signals are sent out via corresponding OTN connections AOl to A04.
  • the switching matrixes, converters, port circuits and network connection circuits are controlled by a CON controller or by a management system.
  • FIG. 3 shows a variant of the cross connector in which STM-16 and OTU-1 signals are permitted as OTN switching matrix signals.
  • the OTU-1 signals are obtained by optoelectric conversion and, if necessary, by additional demultiplexing from received optical transport signals OTM-1 or OTM-2 signals.
  • the OTU-1 signals can be distributed directly via the OTN switching matrix or fed to a converter device U22, which converts them into STM-16 signals. Due to the STM-16 / OTU-1 implementation, the effort in the network connection circuits is lower, but the signals switched through between different network elements cannot be monitored so effectively, especially with only implemented OTU-1 signals, since no termination and none Error correction is done.
  • a conversion into VC switching matrix signals takes place in the converter devices UlO and U12.
  • An error correction can also be carried out here or a corresponding coding can be carried out in the transmitter direction.
  • Figure 4 also shows a cross connector. However, this is simpler because only one data format ODU-1 is switched through in the OTN switching matrix OTN-KF. This is obtained from the received optical transport modules OTM-1 or OTM-2 by appropriate network connection circuits NAH to NAln or NA21 to NA2n, which additionally contain time-division multiplexing devices. Since only one data format needs to be switched in the OTN switching matrix, it is therefore not necessary to use a transparent switching matrix, but a conventional switching matrix can be used. Only a single converter device Uli is required, the ISDH connections of which can be connected directly to the VC switching matrix VC-KF. Through the VC switching matrix is another transition between the two networks was established. It is also possible to switch within the optical transport network with VC-4/3 granularity.
  • FIG. 5 shows a further variant, in which STM-16 signals are switched through as switching matrix signals and likewise only one converter device UlO is provided.
  • FIG. 6 shows an OTN Crossconnector CC-O, which is not designed for the transition of data from the OTN network to an SDH network.
  • the OTN switching matrix OTN-TKF is designed as a transparent switching matrix because different data formats, here ODU-1 and STM-16, are to be switched through.
  • the network connection elements NAH to NA2n correspond to those from FIG. 2. Only one converter device U21 is provided, which can convert a plurality of STM-16 into ODU-1 signals and vice versa. This enables an arbitrary distribution of the data streams in the OTN optical transport network, usually only a few converters being required.
  • FIG. 7 shows an extended OTN Crossconnector CC-OE, which, however, additionally contains the VC switching matrix VC-KF.
  • UlO and Uli which convert STM-16 and ODU-1 formats into the ISDH format.
  • Received optical transport signals OTM-1, OTM-2, WDM-1, WDM-2 are converted into OTN switching matrix signals ODU-1, STM-16 and fed to the Uli and UlO converter devices via the OTN switching matrix and converted into ISDH format. From there they arrive in the VC switching matrix VC-KF.
  • the ISDH the ISDH
  • Signals regrouped are fed back to the converters Uli or UlO, converted there into OTN switching matrix signals and fed back into the optical network via the OTN switching matrix and the network connection circuits. It is therefore possible to distribute the signals in the OTN network again with the granularity of an ISDH signal (VC-4/3 container).

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  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Time-Division Multiplex Systems (AREA)

Abstract

The invention relates to a cross-connector which comprises a first switching matrix (VC-KF) for signals of the synchronous digital SDH hierarchy and a transparent switching matrix (OTN-KF) for optical transport signals. Both switching matrixes are interlinked via converter devices (U10, U11) so that a transition between the two networks is possible and conversion takes place only as required.

Description

Crossconnector zur Übertragung von Signalen zwischen einem SDH/SONET-Netz und einem optischen NetzCrossconnector for the transmission of signals between an SDH / SONET network and an optical network
Beschreibungdescription
Die Erfindung betrifft einen universellen Crossconnector für Signale eines Netzes der Synchronen Digitalen Hierarchie und für Signale eines optischen Transportnetzes; sie betrifft außerdem einen universellen Crossconnector nur für Signale des optischen Transportnetzes.The invention relates to a universal cross connector for signals of a network of the synchronous digital hierarchy and for signals of an optical transport network; it also concerns a universal cross connector only for signals of the optical transport network.
In den regionalen Ubertragungsnetzen Europas werden Übertragungssysteme verwendet, die nach der Synchronen Digitalen Hierarchie, SDH, entsprechend der ITU-Empfehlung G.707 arbeiten. In Nordamerika werden Systeme nach der SONET-Norm einge- setzt, die ebenfalls in der ITU-Empfehlung G.707 festgelegt sind. Diese regionalen Netze sind meist in Ringstrukturen aufgebaut, die bei der Synchronen Digitalen Hierarchie Uber- tragungsbitragen von 155 Mbit/s für STM-1 Signale, 622 Mbit/s für STM-4 Signale, 2,5 Mbit/s für STM-16 Signale bis zu 10 Gbit/s für STM-64 Signale aufweisen. Höhere Ubertragungsraten werden angestrebt. Die in diesen Netzen übertragenen Nutzsignale werden in sogenannte virtuelle Container VC-n verpackt, mit Granularitaten von 2 Mbit/s für den virtuellen Container VC-12, 34 Mbit/s für VC-3 und 140 Mbit/s für VC-4 Container der SDH- Norm; bei der SONET-Norm mit Granularitaten von 1,5 Mbit/s für VC-11, 6 Mbit/s für VC-2 und 45 Mbit/s für VC-3 Container .The regional transmission networks in Europe use transmission systems that operate according to the synchronous digital hierarchy, SDH, in accordance with ITU recommendation G.707. In North America, systems based on the SONET standard are used, which are also specified in ITU recommendation G.707. These regional networks are mostly built up in ring structures, which in the synchronous digital hierarchy transmit bit rates of 155 Mbit / s for STM-1 signals, 622 Mbit / s for STM-4 signals, 2.5 Mbit / s for STM-16 signals up to 10 Gbit / s for STM-64 signals. Higher transmission rates are aimed for. The useful signals transmitted in these networks are packaged in so-called virtual containers VC-n, with granularities of 2 Mbit / s for the virtual container VC-12, 34 Mbit / s for VC-3 and 140 Mbit / s for VC-4 containers SDH standard; with the SONET standard with granularities of 1.5 Mbit / s for VC-11, 6 Mbit / s for VC-2 and 45 Mbit / s for VC-3 containers.
Zur Verbindung der einzelnen Ringe im regionalen Netz werden häufig Cross Connect Systeme (Kreuzschalteinrichtungen) eingesetzt, die diese virtuellen Container von beliebigen Eingangssports zu beliebigen Ausgangssports durchschallten können.To connect the individual rings in the regional network, cross connect systems (cross-switching devices) are often used, which can pass these virtual containers through from any input port to any output port.
Im nationalen Netz werden mittels Wellenlangen-In the national network,
Multiplexverfahren jeweils aus einer Vielzahl von SDH/SONET- Signalen mit Datenraten von 2,5 Gbit/s, 10 Gbit/s und in na- her Zukunft auch 40 Gbit/s Transportsignale gebildet. Hierbei handelt es sich entweder um SDH/SONET-Signale höherer Ordnung (STM-16/64/256) oder Signale nach der neuen ITU Norm G. 709. Entsprechend der Empfehlung G. 709 werden STM-16/64/256 Sig- nale zusatzlich um Overheadinformation und zusatzlichen Kontrollbits zur Fehlerkorrektur, FEC, zu OTU-1/2/3 Signalen erweitert. Mehrere dieser Signale werden wiederum zu einem Wel- lenlangen-Multiplexsignal, WDM, zusammengefasst und in einem optischen Transportnetz, OTN, übertragen. Die optischen Transportnetze sind durchwegs als vermaschte Netze mit Punkt zu Punkt Verbindungen zwischen den einzelnen Netzelementen aufgebaut. Die Granularitat der Signale im OTN betragt STM- 16/64/256 bzw. OTU-1/2/3, d. h., die kleinste Bitrate, die im OTN geschaltet werden kann, betragt 2,5 Gbit/s. Auch hier sind optische Cross Connect Systeme zur Verteilung der Nutzsignale vorgesehen.Multiplex process each from a variety of SDH / SONET signals with data rates of 2.5 Gbit / s, 10 Gbit / s and in na- ago 40 Gbit / s transport signals formed. These are either higher-order SDH / SONET signals (STM-16/64/256) or signals according to the new ITU standard G. 709. According to recommendation G. 709, STM-16/64/256 signals are used additionally expanded by overhead information and additional control bits for error correction, FEC, to OTU-1/2/3 signals. Several of these signals are in turn combined to form a wavelength multiplex signal, WDM, and transmitted in an optical transport network, OTN. The optical transport networks are all constructed as meshed networks with point-to-point connections between the individual network elements. The granularity of the signals in the OTN is STM-16/64/256 or OTU-1/2/3, ie the smallest bit rate that can be switched in the OTN is 2.5 Gbit / s. Optical cross connect systems for distributing the useful signals are also provided here.
Für den Übergang zwischen dem regionalen SDH/SONET Netz (im Folgenden nur als SDH-Netz bezeichnet) und dem nationalen „Optischen Netz* soll ein Crossconnector angegeben werden, der ein hohes Maß an Flexibilität bietet und kostengünstig realisierbar ist.For the transition between the regional SDH / SONET network (hereinafter only referred to as the SDH network) and the national "optical network *", a cross connector should be specified that offers a high degree of flexibility and is inexpensive to implement.
Zur Realisierung von Cross Connect Funktionen im Optischen Transportnetz soll ebenfalls eine vereinfachte Einrichtung angegeben werden.To implement cross connect functions in the optical transport network, a simplified setup should also be specified.
Außerdem soll auch im Optischen Transportnetz ein Durchschalten mit einer feineren Granularitat ermöglicht werden, die eine feinere Granularitat bei der Verteilung der Nutzsignale ermöglicht.In addition, switching through with a finer granularity should also be made possible in the optical transport network, which enables a finer granularity in the distribution of the useful signals.
Die Hauptaufgabe wird durch ein Crossconnector System nach den Merkmalen des Patentanspruchs 1 gelost.The main task is solved by a cross connector system according to the features of claim 1.
Ein Crossconnector für das optische Transportnetz ist im unabhängigen Anspruch 3 angegeben. Der wesentliche Vorteil der Erfindung wird durch zwei Koppelfelder und Umsetzer erreicht. OTN-Leitungsanschlüsse sind an Anschlüsse eines OTN Koppelfeldes angeschaltet und SDH- Leitungsanschlüsse an ein SDH-Koppelfeld. Diese Koppelfelder können jeweils OTN-Signale bzw. SDH-Signale durchschalten. Die Umsetzer ermöglichen Schaltoperationen zwischen SDH- und OTN-Datenformaten. Außerdem können OTN-Koppelfeldsignale mit einer SDH-Granularität geschaltet werden. Da Umsetzer nur im Bedarfsfall verwendet werden, ist diese Lösung besonders kos- tengünstig.A cross connector for the optical transport network is specified in independent claim 3. The main advantage of the invention is achieved by two switching matrixes and converters. OTN line connections are connected to connections of an OTN switching matrix and SDH line connections to an SDH switching matrix. These switching networks can switch through OTN signals or SDH signals. The converters enable switching operations between SDH and OTN data formats. In addition, OTN switching matrix signals can be switched with an SDH granularity. Since converters are only used when needed, this solution is particularly cost-effective.
Bei der Verwendung von mehreren Umsetzern können auch unterschiedliche OTN-Formate geschaltet werden.When using several converters, different OTN formats can also be switched.
Werden verschiedene OTN-Formate - und hierdurch bedingt - verschiedene OTN-Koppelfeldsignale verwendet, sind ein transparentes Koppelfeld zweckmäßig und mehrere Umsetzertypen erforderlich.If different OTN formats - and as a result of this - different OTN switching matrix signals are used, a transparent switching matrix is appropriate and several types of converters are required.
Bei dem OTN Crossconnector, der lediglich OTN-Formate durchschaltet, gelten die gleichen Vorteile. Mit Hilfe des SDH/SONET Koppelfeldes kann bei einer feineren Granularitat geschaltet werden.The same advantages apply to the OTN Crossconnector, which only switches through OTN formats. With the help of the SDH / SONET switching matrix, switching can be carried out with a finer granularity.
Sonstige vorteilhafte Weiterbildungen der Erfindungen sind in den übrigen Unteransprüchen angegeben und in der Beschreibung näher erläutert.Other advantageous developments of the inventions are specified in the remaining subclaims and explained in more detail in the description.
Verschiedene Ausführungsbeispiele der Erfindung werden anhand von Figuren näher erläutert.Various exemplary embodiments of the invention are explained in more detail with reference to figures.
Es zeigenShow it
Figur 1 ein SDH/SONET-Netz und ein OTN-Netz mit Cross Connect Einrichtungen,FIG. 1 shows an SDH / SONET network and an OTN network with cross connect devices,
Figur 2 einen universalen Crossconnector,FIG. 2 shows a universal cross connector,
Figur 3 eine Variante mit mehreren OTN-Koppelfeldsignalen, Figur 4 einen vereinfachten Crossconnector für STM-16-Signa- le,FIG. 3 shows a variant with several OTN switching matrix signals, FIG. 4 shows a simplified cross connector for STM-16 signals,
Figur 5 einen vereinfachten Crossconnector für ODU-1 Signale, Figur 6 einen OTN Crossconnector und Figur 7 einen erweiterten OTN Crossconnector.5 shows a simplified cross connector for ODU-1 signals, FIG. 6 shows an OTN cross connector and FIG. 7 shows an expanded OTN cross connector.
Figur 8 die Rahmenstruktur eines STM-N Signals und VC-4 Containers und Figur 9 die Rahmenstruktur eines ODU/OTU-Signals .Figure 8 shows the frame structure of an STM-N signal and VC-4 container and Figure 9 shows the frame structure of an ODU / OTU signal.
Figur 1 zeigt ein SDH/SONET-Netz SDH-N mit mehreren Ringnetzen STM-4-N, STM-16-N unterschiedlicher Datenrate, die jeweils mehrere Add/Drop-Multiplexer ADM aufweisen. Diese Netze sind über einen Crossconnector CC-SO mit einem optischen Transportnetz OTN verbunden, das mehrere optische Netzelemen- te ONE und weitere Crossconnectoren CC-S02, CC-S03 sowie einen OTN-Crossconnector CC-0 aufweist.FIG. 1 shows an SDH / SONET network SDH-N with a plurality of ring networks STM-4-N, STM-16-N of different data rates, each of which has a number of add / drop multiplexers ADM. These networks are connected via a cross connector CC-SO to an optical transport network OTN which has a plurality of optical network elements ONE and further cross connectors CC-S02, CC-S03 and an OTN cross connector CC-0.
Der Crossconnector CC-SO ermöglicht sowohl eine flexible Ver- schaltung von SDH/SONET-Signalen STM-N im SDH-Netz als auch eine flexible Verschaltung von optischen Transportsignalen des OTN-Netzes und dient außerdem als Verbindung zwischen beiden Netzen.The Crossconnector CC-SO enables flexible interconnection of SDH / SONET signals STM-N in the SDH network as well as flexible interconnection of optical transport signals of the OTN network and also serves as a connection between the two networks.
Der Crossconnector CC-SO ist ein Gegenstand dieser Erfindung. Das dieser Erfindung zugrunde liegende Prinzip wurde auch bei dem OTN Crossconnector CC-0 genutzt, um unterschiedliche Datenformate des optischen Transportnetzes OTN ineinander zu überführen und zu verteilen.The cross connector CC-SO is an object of this invention. The principle on which this invention is based was also used in the OTN Crossconnector CC-0 in order to convert and distribute different data formats of the optical transport network OTN into one another.
Figur 2 zeigt in symbolischer Darstellung den Crossconnector CC-SO. Diese enthält zwei miteinander über Umsetzereinrichtungen U10, Uli, U21 korrespondierende Koppelfelder VC-KF und OTN-TKF für unterschiedliche Datenformate und mit Anschlussschaltungen, die den Crossconnector mit beiden Netzen verbin- den. Das erste Koppelfeld VC-KF ist für Signale einer Synchronen Digitalen Hierarchie STM-N konzipiert und wird im Folgenden als VC-Koppelfeld bezeichnet. Auch bei den Signalbezeichnungen erfolgt eine beispielhafte Beschränkung auf SDH-Signale obwohl das Koppelfeld auch für SONET-Signale konzipiert sein kann. Die Transportsignale (Transportmodule) STM-N werden an den SDH-Anschlüssen (jeweils Ein- und Ausgänge) AS1 bis ASm empfangen und ausgesendet. An Koppelfeldanschlüsse (Ein- und Ausgänge) sind Portschaltungen PS1 bis PSm angeschaltet, die die empfangenen STM-Transportsignale entsprechend den ITU- Empfehlungen verarbeiten, d. h., dass Regenerator- und Multiplexer-Sektion Overhead, RSOH und MSOH, terminiert werden und die Nutzsignale in Form von virtuellen Containern VC-4 bei SDH (bzw. VC-3 bei SONET) zurückgewonnen werden.Figure 2 shows a symbolic representation of the cross connector CC-SO. This contains two coupling fields VC-KF and OTN-TKF, which correspond to one another via converter devices U10, Uli, U21, for different data formats and with connection circuits that connect the cross-connector to both networks. The first switching matrix VC-KF is designed for signals of a synchronous digital hierarchy STM-N and is referred to below as a VC switching matrix. The signal names are also limited to SDH signals, although the switching matrix can also be designed for SONET signals. The transport signals (transport modules) STM-N are received and sent at the SDH connections (inputs and outputs) AS1 to ASm. Port switches PS1 to PSm are connected to switching network connections (inputs and outputs), which process the received STM transport signals in accordance with the ITU recommendations, i.e. that the regenerator and multiplexer section overhead, RSOH and MSOH are terminated and the useful signals in the form can be recovered from virtual containers VC-4 at SDH (or VC-3 at SONET).
Das Format der STM-N Transportmodule sowie der von N darin enthaltener Container VC-4 ist in Figur 8 dargestellt und entspricht Figur 8-8, der ITU-Empfehlung G.707, 03/1996. Außerdem ist ein Umpointern der Nutzsignale erforderlich, um diese an die Taktrate des Crossconnectors CC-SO anzupassen. Hierunter wird verstanden, dass der Pointer des ankommenden Signals, der auf das erste Byte des virtuellen Containers zeigt, entsprechend der Phase und der Frequenz des Rahmentaktes des SDH-Koppelfeldes neu berechnet wird. Die so behandel- ten Signale werden als Koppefeldsignale ISDH an das VC- Koppelfeld geführt.The format of the STM-N transport modules and the container VC-4 contained therein by N is shown in FIG. 8 and corresponds to FIG. 8-8, ITU recommendation G.707, 03/1996. A repositioning of the useful signals is also required in order to adapt them to the clock rate of the cross connector CC-SO. This is understood to mean that the pointer of the incoming signal, which points to the first byte of the virtual container, is recalculated in accordance with the phase and frequency of the frame clock of the SDH switching matrix. The signals treated in this way are routed to the VC switching matrix as switching matrix signals ISDH.
Die internen Koppefeldsignale ISDH weisen vorzugsweise eine SDH-ähnliche Struktur auf, aber beinhalten beispielsweise nicht den Regenerator und Sektion Overhead. Sie entsprechen etwa dem VC-4 Container, gegebenenfalls ergänzt um interne Koppelfeldinformation.The internal switching matrix signals ISDH preferably have an SDH-like structure, but do not include, for example, the regenerator and section overhead. They correspond approximately to the VC-4 container, possibly supplemented by internal switching matrix information.
In der Senderichtung werden durch die Portschaltungen PS1 bis PSm in entsprechender Weise ISDH bzw. modifizierte VC-4 bzw. VC-3 Signale gemultiplext und unter Hinzufügen des Multiple- xer und Regenerator Sektion Overheads STM-N Signale gebildet. Figur 2 ist demnach als Prinzipschaltbild für beide Übertragungsrichtungen zu verstehen, bei dem an den Anschlüssen AS1 bis ASn Signale sowohl empfangen als auch ausgesendet werden. Diese Darstellungsform ist auch in den ITU-Empfehlungen üb- lieh.In the transmission direction, ISDH or modified VC-4 or VC-3 signals are multiplexed in a corresponding manner by port circuits PS1 to PSm and, with the addition of the multiplier and regenerator section overhead, STM-N signals are formed. FIG. 2 is therefore to be understood as a basic circuit diagram for both transmission directions, in which signals are both received and transmitted at the connections AS1 to ASn. This form of presentation is also used in the ITU recommendations.
Das VC-Koppelfeld VC-KF ermöglicht zunächst die freizügige Verschaltung (Kreuzschaltung) einzelner bestimmten Containern zugeordneter elektrischer Koppelfeldsignale ISDH zwischen be- liebigen Portschaltungen und damit zwischen beliebigen SDH- Ansc lüssen AS1 bis ASm.The VC switching matrix VC-KF initially enables the free interconnection (cross-connection) of individual electrical switching signals ISDH assigned to specific containers between any port switching and thus between any SDH connections AS1 to ASm.
Das VC-Koppelfeld ist nun logisch (d.h. direkt oder über das OTN-Koppelfeld) über die Umsetzereinrichtungen U10, Uli, U21 mit dem OTN-Koppelfeld verbunden. Dieses ist in diesem Ausführungsbeispiel als transparentes Koppelfeld OTN-TKF ausgeführt, da es unterschiedliche Formate von OTN- Koppelfeldsignalen, beispielsweise ODU-1 (Optical Data Unit) und STM-16, in elektrischer Form durchschalten muss. Diese Signale sind beispielsweise aus optischen Transportsignalen OTU-1, OTU-2 durch Demultiplexen und gegebenenfalls Umsetzung in ein anderes Datenformat gewonnen worden oder über einen separaten Kanal übertragen worden. Auch die OTN- Koppelfeldsignale können ebenfalls zusätzlich interne Koppel- feldinformation enthalten.The VC switching matrix is now logically (i.e. directly or via the OTN switching matrix) connected to the OTN switching matrix via the converter devices U10, Uli, U21. In this exemplary embodiment, this is implemented as a transparent switching network OTN-TKF, since it has to switch through different formats of OTN switching network signals, for example ODU-1 (Optical Data Unit) and STM-16, in electrical form. These signals have been obtained, for example, from optical transport signals OTU-1, OTU-2 by demultiplexing and, if appropriate, conversion into another data format or have been transmitted via a separate channel. The OTN switching matrix signals can also contain additional internal switching matrix information.
Die OTN-Koppelfeldsignale können ebenfalls direkt oder nach Umsetzung in ein anderes OTN-Datenformat, beispielsweise OTU-1 in STM-16, im OTN-Koppelfeld verteilt und über unter- schiedliche OTN-Anschlüsse AOl bis A04 im Optischen Transportnetz weitergesendet werden. Sie können aber ebenfalls ü- ber Umsetzeinrichtungen U10 und Uli zum VC-Koppelfeld VC-KF durchgeschaltet werden.The OTN switching matrix signals can also be distributed directly or after conversion to another OTN data format, for example OTU-1 in STM-16, in the OTN switching matrix and forwarded via different OTN connections AOl to A04 in the optical transport network. However, they can also be switched through to the VC switching matrix VC-KF via conversion devices U10 and Uli.
Die Umsetzerfunktion von U10 besteht darin, in einer Richtung ein vom VC-Koppelfeld kommendes ISDH Signalbündel, bestehend aus 16 VC-4 bzw. 48 VC-3 Signalen, unter Hinzufügen der er- forderlichen Overheads RSOH und MSOH zu einem STM-16 Signal zu ergänzen, das dann im transparenten OTN-Koppelfeld beliebig durchgeschaltet werden kann und so eine Verbindung zwischen dem SDH-Netz und dem OTN herstellt.The U10 converter function consists in one direction of an ISDH signal bundle coming from the VC switching matrix, consisting of 16 VC-4 or 48 VC-3 signals, adding the the required overheads RSOH and MSOH to a STM-16 signal, which can then be switched through in the transparent OTN switching matrix and thus creates a connection between the SDH network and the OTN.
Im Gegenrichtung werden im Umsetzer UlO von dem optischen Transportnetz OTN kommende STM-16 Signale terminiert, die 16 VC-4 bzw. 48 VC-3 Signale werden durch Umpointern an die Taktrate des VC-Koppelfeldes VC-TKF angepasst, so in VC- Koppelfeldsignale ISDH umgesetzt, um über das VC-Koppelfeld in das SDH-Netz zu gelangen.In the opposite direction, STM-16 signals coming from the optical transport network OTN are terminated in the converter UlO; the 16 VC-4 or 48 VC-3 signals are adapted to the clock rate of the VC switching matrix VC-TKF by repointering, thus in VC switching matrix signals ISDH implemented to access the SDH network via the VC switching network.
Die Umsetzereinrichtung Uli hat die Aufgabe, in einer Richtung ein ISDH Signalbündel zunächst durch Hinzufügen von 0- verheads RSOH und MSOH zu einem STM-16 Signal zu ergänzen.The converter device Uli has the task of initially supplementing an ISDH signal bundle in one direction by adding 0-threads RSOH and MSOH to an STM-16 signal.
Durch Hinzufügen des „Optical Channel Payload Unit Overheads* OPU OH und des„Optical Channel Data Unit Overheads* ODU OH wird ein ODU-1 Signal gebildet, das im OTN-Koppelfeld durchgeschaltet werden kann (Figur 9) . In Gegenrichtung wird das ODU-1 Signal zunächst im Umsetzer Uli terminiert und das zurückgewonnene STM-16 Signal wird wie im Umsetzer UlO zu einem ISDH Koppelfeldsignal weiterverarbeitet.By adding the "Optical Channel Payload Unit Overhead * OPU OH and the" Optical Channel Data Unit Overhead * ODU OH, an ODU-1 signal is formed which can be switched through in the OTN switching matrix (FIG. 9). In the opposite direction, the ODU-1 signal is first terminated in the Uli converter and the recovered STM-16 signal is further processed, as in the UlO converter, to form an ISDH switching matrix signal.
Durch das Zusammenwirken beider Koppelfelder ist auch ein Schalten von OTN Signalen mit VC-4/3 Granularitat möglich, indem ein OTN-Koppelfeldsignal über einen Umsetzer und das VC-Koppelfeld geführt und anschließend über diesen Umsetzer oder einen anderen Umsetzer in ein OTN-Koppelfeldsignal umgesetzt dem OTN-Netz zugeführt wird.The interaction of the two switching matrixes also enables switching of OTN signals with VC-4/3 granularity by passing an OTN switching matrix signal over a converter and the VC switching matrix and then converting it into an OTN switching matrix signal via this converter or another converter is supplied to the OTN network.
Außerdem ist es durch die Umsetzereinrichtung U21 möglich, unterschiedliche OTN-Koppelfeldsignale ODU-1 und STM-16 über das transparente OTN-Koppelfeld durchzuschalten und diese ineinander umzusetzen. Diese Umsetzung kann auch über die bei- den Umsetzeinrichtungen UlO und Uli erfolgen. Die Umsetzerfunktion von U21 besteht in der einen Richtung darin, ein STM-16 Signal durch Hinzufügen von Overheads in ein ODU-1 Signal umzusetzen, das im transparenten OTN-Koppelfeld OTN- TKF verschaltet werden kann. In Gegenrichtung wird das ODU-1 Signal terminiert und das zurückgewonnene STM-16 Signal kann wieder im transparenten Koppelfeld verschaltet werden.In addition, the converter device U21 makes it possible to connect different OTN switching matrix signals ODU-1 and STM-16 through the transparent OTN switching matrix and to convert them into one another. This implementation can also take place via the two conversion devices UlO and Uli. The U21 converter function is, in one direction, an STM-16 signal by adding overheads to an ODU-1 Implement signal that can be interconnected in the transparent OTN switching matrix OTN-TKF. The ODU-1 signal is terminated in the opposite direction and the recovered STM-16 signal can be connected again in the transparent switching matrix.
Zur Umsetzungen von Datenformaten sind ebenfalls die an das OTN-Koppelfeld angeschalteten Netzanschlussschaltungen NAH bis NA2n vorgesehen.The network connection circuits NAH to NA2n connected to the OTN switching matrix are also provided for converting data formats.
Die Netzanschlussschaltungen NAll-NAln wandeln in Senderichtung jeweils ODU-1 Signale in Optical Channel Transport Units OTU-1 Signale um. Hierzu wird dem ODU-1 Signal ein OTU 0- verhead OTU-OH und eine OTU Forward Error Korrektion Sektion OTU-FEC hinzugefügt. In Figur 9 ist der Pulsrahmen ein- schließlich Overhead eines OTU-1 Signals dargestellt. EineThe network connection circuits NAll-NAln each convert ODU-1 signals into optical channel transport units OTU-1 signals in the transmission direction. For this purpose, an OTU 0 head OTU-OH and an OTU forward error correction section OTU-FEC are added to the ODU-1 signal. FIG. 9 shows the pulse frame including the overhead of an OTU-1 signal. A
Erläuterung der Abkürzungen ist hier nicht notwendig, da diese für die Erfindung unwesentlich sind.Explanation of the abbreviations is not necessary here, since these are not essential to the invention.
Durch eine elektrisch/optischen Wandlung werden von den Netz- anschlussschaltungen NAH -NAln optische Signale mit bestimmten Wellenlängen λl bis λn erzeugt, die in einer Wellenlän- gen-Multiplexeinrichtung Wl zu einem „Optical Transport Modul* Signal OTM-1 zusammengefasst und ausgesendet werden. In Empfangsrichtung erfolgt zunächst eine Aufspaltung des Wel- lenlängen-Multiplexsignals. Dann wird jeweils in den Netzanschlussschaltungen eine Fehlerkorrektur durchgeführt; der OTU-Overhead OTU-OH wird terminiert und aus OTU-1 Signalen werden ODU-1 Signale mit Wellenlängen λl bis λn zurückgewonnen.By means of an electrical / optical conversion, the network connection circuits NAH-NAln generate optical signals with specific wavelengths λl to λn, which are combined in a wavelength division multiplexing device Wl to form an “Optical Transport Module * Signal OTM-1 and transmitted. The wavelength multiplex signal is first split in the receiving direction. Then an error correction is carried out in each case in the network connection circuits; the OTU overhead OTU-OH is terminated and ODU-1 signals with wavelengths λl to λn are recovered from OTU-1 signals.
Die Netzanschlussschaltungen NA21 bis NA2n weisen zusätzliche Multiplex- und Demultiplex-Einrichtungen auf, mit denen in Senderichtung 4 ODU-1 Signale zu einem ODU-2 Signal zusammengefasst werden. Hierzu werden den 4 ODU-1 Signalen ein ent- sprechender Overhead und entsprechende Korrekturbytes hinzugefügt. Nach einer elektrisch/optischen Wandlung werden die optischen Ausgangssignale der Netzanschlussschaltungen zu ei- nem Optical Transport Modul Signal OTM-2 zusa mengefasst . In Empfangsrichtung werden aus dem OTM-2 Signal wiederum Signale mit Wellenlange λl bis λn gewonnen und in den Netzanschlussschaltungen nach einer Fehlerkorrektur und Terminierung ODU-1 Signale gewonnen.The mains connection circuits NA21 to NA2n have additional multiplex and demultiplex devices with which 4 ODU-1 signals are combined to form an ODU-2 signal in the transmission direction. A corresponding overhead and corresponding correction bytes are added to the 4 ODU-1 signals. After an electrical / optical conversion, the optical output signals of the mains connection circuits are Optical Transport Module Signal OTM-2. In the receiving direction, signals with wavelengths λl to λn are again obtained from the OTM-2 signal and ODU-1 signals are obtained in the network connection circuits after error correction and termination.
Anstelle des Multiplexens von 4 ODU-1 Signalen in ein OTU-2 Signal kann naturlich auch ein Multiplexen und von 16 ODU-1 Signalen in ein OTU-3 Signal vorgesehen werden.Instead of multiplexing 4 ODU-1 signals into one OTU-2 signal, multiplexing and of 16 ODU-1 signals into one OTU-3 signal can of course also be provided.
Weitere Netzanschlussschaltungen, die Transponder TR1 bis TRn, wandeln in Senderichtung jeweils ein elektrisches STM-16 Signal in ein optisches Signal mit einer bestimmten Wellenlange λl bis λn um. Die optischen Signale werden in einer Wellenlangen-Multiplexeinrichtung W3 zu einem WDM-Signal WDM- 1 zusammengefasst. In Empfangsrichtung werden aus dem Signal WDM-1 durch Filter einzelne Signale mit Wellenlangen λl bis λn gewonnen und in einem Transponder in elektrische STM-16 Signale zuruckgewandelt .Further network connection circuits, the transponders TR1 to TRn, each convert an electrical STM-16 signal into an optical signal with a specific wavelength λl to λn in the transmission direction. The optical signals are combined in a wavelength multiplexing device W3 to form a WDM signal WDM-1. In the receiving direction, individual signals with wavelengths λl to λn are obtained from the signal WDM-1 by filters and converted back into electrical STM-16 signals in a transponder.
Für höhere Ubertragungsraten sind als Netzanschlussschaltungen Multiplexeinrichtungen MUX1 bis MUXn vorgesehen, die in Senderichtung jeweils 4 STM-16 Signale zu einem optischen STM-64 Signal mit bestimmten Wellenlangen λl bis λn zusammen- fassen. Die STM-64 Signale werden in einer Wellenlangen-Mul- tiplexemrichtung W4 zu einem Signal WDM-2 gemultiplext . In Empfangsrichtung wird ein empfangenes WDM-2-Sιgnal in Einzelsignale λl bis λn aufgeteilt und in den Multiplexeinrichtungen MUX1 bis MUXn in elektrische STM-16 Signale aufgeteilt.For higher transmission rates, multiplex devices MUX1 to MUXn are provided as network connection circuits, each of which combines 4 STM-16 signals in the transmission direction to form an optical STM-64 signal with specific wavelengths λl to λn. The STM-64 signals are multiplexed in a wavelength multiplexing device W4 to form a signal WDM-2. In the receiving direction, a received WDM-2 signal is divided into individual signals λl to λn and divided into electrical STM-16 signals in the multiplexing devices MUX1 to MUXn.
Anstelle eines Multiplexens von vier STM-16 Signale in ein STM-64 Signal kann naturlich auch ein Multiplexen von 16 STM- 16 Signalen in ein STM-256 Signal usw. durch entsprechend konzipierte Multiplex-Einπchtungen vorgesehen werden.Instead of multiplexing four STM-16 signals into one STM-64 signal, multiplexing of 16 STM-16 signals into one STM-256 signal etc. can of course also be provided by appropriately designed multiplex devices.
Die Signale werden über entsprechende OTN-Anschlusse AOl bis A04 ausgesendet. Die Koppelfelder, Umsetzer, Portschaltungen und Netzanschlussschaltungen werden über eine Steuerung CON bzw. von einem Managementsystem gesteuert.The signals are sent out via corresponding OTN connections AOl to A04. The switching matrixes, converters, port circuits and network connection circuits are controlled by a CON controller or by a management system.
Figur 3 zeigt eine Variante des Crossconnectors, bei der als OTN-Koppelfeldsignale STM-16 und OTU-1 Signale zugelassen sind. Die OTU-1 Signale werden durch optoelektrische Umwandlung und gegebenenfalls durch zusätzliches Demultiplexen aus empfangenen optischen Transportsignalen OTM-1 bzw. OTM-2 Sig- nalen gewonnen. Die OTU-1 Signale können direkt über das OTN- Koppelfeld verteilt werden oder einer Umsetzereinrichtung U22 zugeführt werden, die diese in STM-16 Signale umsetzt. Durch die STM-16/OTU-1 Umsetzung ist zwar der Aufwand in den Netzanschlussschaltungen geringer, dafür können die zwischen ver- schiedenen Netzelementen durchgeschalteten Signale aber nicht so wirkungsvoll überwacht werden, insbesondere bei lediglich durchgeführten OTU-1 Signalen, da keine Terminierung und keine Fehlerkorrektur erfolgt.FIG. 3 shows a variant of the cross connector in which STM-16 and OTU-1 signals are permitted as OTN switching matrix signals. The OTU-1 signals are obtained by optoelectric conversion and, if necessary, by additional demultiplexing from received optical transport signals OTM-1 or OTM-2 signals. The OTU-1 signals can be distributed directly via the OTN switching matrix or fed to a converter device U22, which converts them into STM-16 signals. Due to the STM-16 / OTU-1 implementation, the effort in the network connection circuits is lower, but the signals switched through between different network elements cannot be monitored so effectively, especially with only implemented OTU-1 signals, since no termination and none Error correction is done.
In den Umsetzereinrichtungen UlO und U12 erfolgt eine Umsetzung in VC-Koppelfeldsignale. Hier kann auch eine Fehlerkorrektur durchgeführt werden bzw. in Senderrichtung eine entsprechende Kodierung erfolgen.A conversion into VC switching matrix signals takes place in the converter devices UlO and U12. An error correction can also be carried out here or a corresponding coding can be carried out in the transmitter direction.
Figur 4 zeigt ebenfalls einen Crossconnector. Dieser ist jedoch einfacher ausgeführt, da nur ein Datenformat ODU-1 im OTN-Koppelfeld OTN-KF durchgeschaltet wird. Dieses wird aus den empfangenen optischen Transportmodulen OTM-1 oder OTM-2 durch entsprechende Netzanschlussschaltungen NAH bis NAln bzw. NA21 bis NA2n, die zusätzlich Zeitmultiplexeinrichtungen enthalten, gewonnen. Da nur ein Datenformat im OTN-Koppelfeld geschaltet zu werden braucht, ist es folglich auch nicht erforderlich, ein transparentes Koppelfeld zu verwenden, sondern es kann ein herkömmliches Koppelfeld eingesetzt werden. Es ist auch nur eine einzige Umsetzereinrichtung Uli erforderlich, deren ISDH-Anschlüsse direkt mit dem VC-Koppelfeld VC-KF verbunden werden können. Durch das VC-Koppelfeld ist wieder ein Übergang zwischen beiden Netzen hergestellt. Ebenso kann auch innerhalb des Optischen Transportnetzes mit VC- 4/3 Granularitat geschaltet werden.Figure 4 also shows a cross connector. However, this is simpler because only one data format ODU-1 is switched through in the OTN switching matrix OTN-KF. This is obtained from the received optical transport modules OTM-1 or OTM-2 by appropriate network connection circuits NAH to NAln or NA21 to NA2n, which additionally contain time-division multiplexing devices. Since only one data format needs to be switched in the OTN switching matrix, it is therefore not necessary to use a transparent switching matrix, but a conventional switching matrix can be used. Only a single converter device Uli is required, the ISDH connections of which can be connected directly to the VC switching matrix VC-KF. Through the VC switching matrix is another transition between the two networks was established. It is also possible to switch within the optical transport network with VC-4/3 granularity.
Figur 5 zeigt eine weitere Variante, bei der als Koppelfeldsignale STM-16 Signale durchgeschaltet werden und ebenfalls nur eine Umsetzereinrichtung UlO vorgesehen ist.FIG. 5 shows a further variant, in which STM-16 signals are switched through as switching matrix signals and likewise only one converter device UlO is provided.
Figur 6 zeigt einen OTN Crossconnector CC-O, der nicht für den Übergang von Daten vom OTN-Netz zu einem SDH-Netz konzipiert ist. Das OTN-Koppelfeld OTN-TKF ist als transparentes Koppelfeld konzipiert, da unterschiedliche Datenformate, hier ODU-1 und STM-16, durchgeschaltet werden sollen. Die Netzanschlusselemente NAH bis NA2n entsprechen denen aus Figur 2. Es ist nur eine Umsetzereinrichtung U21 vorgesehen, die mehrere STM-16 in ODU-1 Signale und umgekehrt umsetzen kann. Hierdurch ist eine beliebige Verteilung der Datenströme im Optischen Transportnetz OTN möglich, wobei meist nur wenige Umsetzer erforderlich sind.Figure 6 shows an OTN Crossconnector CC-O, which is not designed for the transition of data from the OTN network to an SDH network. The OTN switching matrix OTN-TKF is designed as a transparent switching matrix because different data formats, here ODU-1 and STM-16, are to be switched through. The network connection elements NAH to NA2n correspond to those from FIG. 2. Only one converter device U21 is provided, which can convert a plurality of STM-16 into ODU-1 signals and vice versa. This enables an arbitrary distribution of the data streams in the OTN optical transport network, usually only a few converters being required.
Figur 7 zeigt einen erweiterten OTN Crossconnector CC-OE, der aber zusätzlich das VC-Koppelfeld VC-KF enthält. Außer der STM-16/ODU-1 Umsetzereinrichtung U21 sind weitere schon bekannte Umsetzereinrichtungen UlO und Uli vorhanden, die STM- 16 bzw. ODU-1 Formate in das ISDH-Format umsetzen. Empfangene optische Transportsignale OTM-1, OTM-2, WDM-1, WDM-2 werden in OTN-Koppelfeldsignale ODU-1, STM-16 umgesetzt und über das OTN Koppelfeld den Unsetzeinrichtungen Uli und UlO zugeführt und ins ISDH-Format umgesetzt. Von dort gelangen sie ins VC- Koppelfeld VC-KF. Im VC-Koppelfeld VC-KF werden die ISDH-FIG. 7 shows an extended OTN Crossconnector CC-OE, which, however, additionally contains the VC switching matrix VC-KF. In addition to the STM-16 / ODU-1 converter device U21, there are other known converter devices UlO and Uli which convert STM-16 and ODU-1 formats into the ISDH format. Received optical transport signals OTM-1, OTM-2, WDM-1, WDM-2 are converted into OTN switching matrix signals ODU-1, STM-16 and fed to the Uli and UlO converter devices via the OTN switching matrix and converted into ISDH format. From there they arrive in the VC switching matrix VC-KF. In the VC switching matrix VC-KF, the ISDH
Signale neu gruppiert den Umsetzern Uli bzw. UlO wieder zugeführt, dort in OTN-Koppelfeldsignale umgesetzt und über das OTN Koppelfeld und die Netzanschlussschaltungen wieder ins optischen Netz eingespeist. Somit ist auch ein Verteilen der Signale im OTN-Netz wieder mit der Granularitat eines ISDH Signals (VC-4/3 Containers) möglich. Signals regrouped are fed back to the converters Uli or UlO, converted there into OTN switching matrix signals and fed back into the optical network via the OTN switching matrix and the network connection circuits. It is therefore possible to distribute the signals in the OTN network again with the granularity of an ISDH signal (VC-4/3 container).

Claims

Patentansprüche claims
1. Universeller Crossconnector (CC-SO) für STM-N Signale eines SDH-Netzes (SDH-N) einer Synchronen Digitalen Hierarchie [SDH, SONET] und für Signale eines optischen Transportnetzes (OTN) , d a d u r c h g e k e n n z e i c h n e t , dass ein VC-Koppelfeld (VC-KF) zum Durchschalten von VC- Koppelfeldsignalen (ISDH) der Synchronen Digitalen Hierarchie zwischen seinen Anschlusspunkten vorgesehen ist, dass ein OTN-Koppelfeld (OTN-TKF) zum Durchschalten von OTN- Koppelfeldsignalen (STM-16, OTU-1, ODU-1) eines Optischen Transportnetzes (OTN) zwischen seinen Anschlusspunkten vorgesehen ist, dass mindestens eine Umsetzereinrichtung (UlO, Uli, U12), die bidirektional OTN-Koppelfeldsignale (STM-16, OTU-1, ODU-1) in VC-Koppelfeldsignale (ISDH) umsetzt, zwischen dem OTN- Koppelfeld (OTN-TKF) und dem VC-Koppelfeld (VC-KF) logisch eingeschaltet ist, so dass Verbindungen zwischen dem SDH-Netz (SDH-N) und dem optischen OTN-Transportnetz (OTN) unter Umsetzung des Datenformats und einer Granularitat des VC- Koppelfeld (VC-KF) schaltbar sind.1. Universal cross connector (CC-SO) for STM-N signals of an SDH network (SDH-N) of a synchronous digital hierarchy [SDH, SONET] and for signals of an optical transport network (OTN), characterized in that a VC switching network ( VC-KF) for switching VC switching network signals (ISDH) of the synchronous digital hierarchy between its connection points, an OTN switching network (OTN-TKF) for switching OTN switching network signals (STM-16, OTU-1, ODU- 1) an optical transport network (OTN) is provided between its connection points, that at least one converter device (UlO, Uli, U12), the bidirectional OTN switching matrix signals (STM-16, OTU-1, ODU-1) to VC switching matrix signals (ISDH ) implements, between the OTN switching network (OTN-TKF) and the VC switching network (VC-KF) is logically switched on, so that connections between the SDH network (SDH-N) and the optical OTN transport network (OTN) are under Implementation of the data format and granularity d VC switching matrix (VC-KF) can be switched.
2. Universeller Crossconnector (CC-SO) nach Anspruch 1, d a d u r c h g e k e n n z e i c h n e t , dass mindestens eine weitere Umsetzereinrichtung (U21, U22) für eine bidirektionale Umsetzung von OTN-Koppelfeldsignalen (STM-16) in jeweils andere OTN-Koppelfeldsignale (ODU-1, OTU- 1) vorgesehen sind.2. Universal cross connector (CC-SO) according to claim 1, characterized in that at least one further converter device (U21, U22) for a bidirectional conversion of OTN switching matrix signals (STM-16) in each other OTN switching matrix signals (ODU-1, OTU - 1) are provided.
3. Universeller Crossconnector (CC-O) für Signale eines optischen Transportnetzes (OTN) , d a d u r c h g e k e n n z e i c h n e t , dass ein OTN-Koppelfeld (OTN-TKF) zum Durchschalten von OTN- Koppelfeldsignalen (STM-16, ODU-1) vorgesehen ist, dass an das OTN-Koppelfeld (OTN-TKF) mindestens eine Umsetzereinrichtung (U21) angeschaltet ist, die bidirektional OTN- Koppelfeldsignale (STM-16) in jeweils andere OTN- Koppelfeldsignale (ODU-1) umsetzt.3. Universal cross connector (CC-O) for signals of an optical transport network (OTN), characterized in that an OTN switching matrix (OTN-TKF) is provided for switching through OTN switching matrix signals (STM-16, ODU-1) the OTN switching matrix (OTN-TKF) is connected to at least one converter device (U21) which bidirectionally OTN Switching matrix signals (STM-16) are converted into other OTN switching matrix signals (ODU-1).
4. Universeller Crossconnector (CC-O) nach Anspruch 3, d a d u r c h g e k e n n z e i c h n e t , dass zusatzlich ein VC-Koppelfeld (VC-KF) zum Durchschalten von VC-Koppelfeldsignalen (ISDH) vorgesehen ist, und dass mindestens eine weitere Umsetzereinrichtung (UlO, Uli) zwischen dem OTN-Koppelfeld (OTN-TKF) und dem VC-Koppelfeld (VC-KF) logisch eingeschaltet ist, die bidirektional OTN- Koppelfeldsignale (STM-16, ODU-1) in VC-Koppelfeldsignale (ISDH) umsetzt, so dass Verbindungen mit einer Granularitat des VC-Koppelfeldes (VC-KF) möglich sind.4. Universal cross connector (CC-O) according to claim 3, characterized in that additionally a VC switching network (VC-KF) is provided for switching VC switching network signals (ISDH), and that at least one further converter device (UlO, Uli) between the OTN switching matrix (OTN-TKF) and the VC switching matrix (VC-KF) is logically switched on, the bidirectional OTN switching matrix signals (STM-16, ODU-1) are converted into VC switching matrix signals (ISDH), so that connections with a granularity of the VC switching matrix (VC-KF) are possible.
5. Universeller Crossconnector nach einem der vorhergehenden Ansprüche, d a d u r c h g e k e n n z e i c h n e t , dass das OTN-Koppelfeld als transparentes Koppelfeld (OTM- TKF) ausgebildet ist, dass mehrere Umsetzereinrichtungen (UlO, Uli, U12) für eine bidirektionale Umsetzung unterschiedlicher OTN- Koppelfeldsignale (STM-16, ODU-1, OTU-1) in VC- Koppelfeldsignale (ISDH) und/oder mehrere Umsetzereinrichtungen (U21, U22) für eine bidirektionale Umsetzung von OTN- Koppelfeldsignalen (STM-16) in jeweils andere OTN- Koppelfeldsignale (ODU-1, OTU-1) vorgesehen sind.5. Universal cross connector according to one of the preceding claims, characterized in that the OTN switching matrix is designed as a transparent switching matrix (OTM-TKF), that several converter devices (UlO, Uli, U12) for a bidirectional implementation of different OTN switching matrix signals (STM-16 , ODU-1, OTU-1) in VC switching matrix signals (ISDH) and / or several converter devices (U21, U22) for bidirectional conversion of OTN switching matrix signals (STM-16) into other OTN switching matrix signals (ODU-1, OTU-1) are provided.
6. Universeller Crossconnector nach einem der Ansprüche 1 - 4, d a d u r c h g e k e n n z e i c h n e t dass das OTN-Koppelfeld (OTN-KF) für ein einziges Format von OTN-Koppelfeldsignalen (ODU-1, STM-16, OTU-1) als nichttransparentes Koppelfeld ausgebildet ist.6. Universal cross connector according to one of claims 1 - 4, so that the OTN switching matrix (OTN-KF) is designed as a non-transparent switching matrix for a single format of OTN switching matrix signals (ODU-1, STM-16, OTU-1).
7. Universeller Crossconnector nach einem der Ansprüche 1, 2,7. Universal cross connector according to one of claims 1, 2,
5, 6, d a d u r c h g e k e n n z e i c h n e t , dass das VC-Koppelfeld (VC-KF) über Portschaltungen (PS1 - PSm) , die bidirektional Transportsignale (STM-N) der Synchronen Digitalen Hierarchie (SDH) in elektrische VC- Koppelfelsignale (ISDH) umsetzen, an des SDH-Netz (SDH-N) an- geschaltet ist.5, 6, characterized, that the VC switching matrix (VC-KF) via port circuits (PS1 - PSm), which convert bidirectional transport signals (STM-N) of the synchronous digital hierarchy (SDH) into electrical VC switching signals (ISDH), on the SDH network (SDH -N) is switched on.
8. Universeller Crossconnector nach einem der vorhergehenden Ansprüchen, d a d u r c h g e k e n n z e i c h n e t , dass das OTN-Koppelfeld (OTN-TKF; OTN-KF) über Netzanschlussschaltungen (NA-11 - NA-ln; NA-21 - NA-2n; TR1 - TRn; MUX1 - MUXn) , die bidirektional elektrische OTN-Koppelfeldsignale (STM-16, OTU-1, ODU-1) in optische Tranportsignale (STM-16, STM-64, OTU-1, OTU-2) umzusetzen, an das Optische Transport- netz (OTN) angeschaltet sind.8. Universal cross connector according to one of the preceding claims, characterized in that the OTN switching network (OTN-TKF; OTN-KF) via network connection circuits (NA-11 - NA-ln; NA-21 - NA-2n; TR1 - TRn; MUX1 - MUXn) to convert the bidirectional electrical OTN switching matrix signals (STM-16, OTU-1, ODU-1) into optical transport signals (STM-16, STM-64, OTU-1, OTU-2) to the optical transport network (OTN) are switched on.
9. Universeller Crossconnector nach Anspruch 8, d a d u r c h g e k e n n z e i c h n e t , dass Wellenlängen-Multiplexeinrichtungen (Wl - W4) an die Netzanschlussschaltungen (NA-11 - NA-ln; NA-21 - NA-2n; TR1 - TRn; MUX1 - MUXn) angeschlossen sind, die bidirektional optische Transportsignale (STM-16, STM-64, OTU-1, OTU-2) in Wel- lenlängenmultiplexsignale (OTM-1, OTM-2, WDM-1, WDM-2) umsetzen.9. Universal cross connector according to claim 8, characterized in that wavelength division multiplexing devices (Wl - W4) are connected to the network connection circuits (NA-11 - NA-ln; NA-21 - NA-2n; TR1 - TRn; MUX1 - MUXn), convert the bidirectional optical transport signals (STM-16, STM-64, OTU-1, OTU-2) into wavelength division multiplex signals (OTM-1, OTM-2, WDM-1, WDM-2).
10. Universeller Crossconnector nach einem der vorhergehenden Ansprüche, d a d u r c h g e k e n n z e i c h n e t , dass die VC-Koppelfeldsignale (ISDH) direkt oder über das OTN-Koppelfeld (OTN-TKF) an die Umsetzereinrichtungen (UlO, Uli, U12) geführt werden. 10. Universal cross connector according to one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t that the VC switching matrix signals (ISDH) are routed directly or via the OTN switching matrix (OTN-TKF) to the converter devices (UlO, Uli, U12).
PCT/DE2003/000578 2002-02-28 2003-02-24 Cross-connector for transmitting signals between an sdh/sonet network and an optical network WO2003073784A1 (en)

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