JP2006074698A - Transmission quality compensation method for optical transmission system, and optical transmission system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform a high-speed transmission characteristic compensation setting operation in all optical networks and to also flexibly deal with a dynamic change of a transmission line. <P>SOLUTION: A control means 7 sets a path comprised of specific nodes 4 and 5 and a link 6 through an independently provided control plane C to a data plane D formed from an optical communication network 3 comprised of the plurality of nodes 4 and 5 and the link 6, information is then communicated from a transmitting side 1 to a receiving side 2 via the set path. With path setting, an instruction to measure the transmission characteristics of the path is imparted from the control means to the transmitting side 1 and the receiving side 2 via the control plane C, and an instruction to set transmission characteristic compensation is imparted from the control means 7 to the receiving side 2 via the control plane C. Communication for measurement is performed via the data plane D in accordance with the instruction to measure the transmission characteristics of the path. On the receiving side 2, the transmission characteristics are measured by the communication for measurement, and transmission characteristic compensation setting is carried out. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a transmission quality compensation method and system in an optical transmission system using an optical communication network, and more particularly to a transmission quality compensation method and system suitable for a high-speed optical transmission system such as an all-optical network communication system.

  In a high-speed optical transmission system of 10 Gbit / s or more using an optical communication network, it is known that transmission quality deteriorates due to transmission characteristics such as wavelength dispersion, spontaneous emission noise light (ASE) of an optical amplifier, and nonlinear optical effect. ing. In particular, since chromatic dispersion increases on the order of the square of the bit rate, it is a major obstacle to the realization of an ultrahigh-speed transmission system exceeding 40 Gbit / s.

  Therefore, in this type of high-speed optical transmission system, there is a technique for providing a chromatic dispersion compensator made of an optical grating or the like having reverse characteristics to the chromatic dispersion characteristics in the transmission path on the receiving apparatus side, and compensating for signal degradation on the receiving side. Proposed. Among these, for example, Patent Document 1 discloses an automatic equalization system that measures the error rate, eye opening, Q value, clock signal level, and the like of received data on the receiving side and equalizes chromatic dispersion according to the measured values. Is disclosed.

As a method for measuring quality and controlling a chromatic dispersion compensator, for example, Non-Patent Document 1 discloses a method for controlling a chromatic dispersion compensator by extracting and measuring a clock from NRZ and RZ signals. Further, as a method for directly observing the chromatic dispersion value, Non-Patent Document 2 discloses a method in which the receiving side measures chromatic dispersion using optical frequency modulation.
Japanese Patent Laid-Open No. 9-326755, paragraph 0014, FIG. "Chromatic dispersion monitoring and automated compensation for NRZ and RZ data using clock regeneration and fading without adding signaling," Z. Pan, Q. Yu, Y. Xie, SA Havstad, AE Willner, DS Starodubov, and J. Feinberg, in Proc OFC 2001, WH5, Mar, 2001 "In-service dispersion monitoring in 32 x 10.7 Gpbs WDM transmission system over transatlantic distance using optical frequency-modulation method," Y. Takushima, H. Yhoshimi, Y. Ozeki, K. Kikuchi, H. Yamauchi, Journal of lightwave technology, vol.22, no.1, Jan. 2004.

However, among the conventional techniques described above, the techniques disclosed in Patent Document 1 and Non-Patent Document 1 receive actual data after setting a path, and the error rate, eye opening degree, Q value, This is a technology that measures the transmission quality such as the clock signal level and adjusts while searching for the optimum point, so it takes time to find the optimum compensation point, which becomes an overhead for speeding up the data transmission process. .
Further, since the technique disclosed in Non-Patent Document 2 performs optical frequency modulation, it is difficult to measure chromatic dispersion normally when a network device that distorts the modulation is inserted on the path. It becomes.

Therefore, a method using fixed fiber parameter characteristics has also been proposed as a technique for realizing high-speed chromatic dispersion compensation (Non-Patent Document 3). In this method, fiber parameters of each link in the optical network are measured in advance, and the optimum compensation value is set in the dispersion compensator by adding the link values necessary for path setting. .
“Rapid automatic chromatic dispersion compensation using GMPLS signaling enhancement for dynamically reconfigurable all-optical network,” H. Hashimoto, et al. In Proc. ECOC2003, Paper Mo4.7.6, Sep. 2003.

  However, with this method, it is necessary to measure the fiber parameters in advance, and the values measured in advance may be different from the values when the path is actually set due to temperature fluctuation, trouble transfer, etc. high. For this reason, it is necessary to perform a measurement and compensation operation corresponding to an all-optical network whose topology dynamically changes and following the optical fiber parameter characteristics which dynamically change. However, in the technique of Non-Patent Document 3 described above, there is a high possibility that the value measured in advance is different from the value when the path is actually set, and it is difficult to perform compensation optimally. Moreover, since it is necessary to hold the data of each wavelength as data for each link, there is also a problem that a lot of information needs to be held.

  The present invention has been made in view of such problems, and is capable of performing a high-speed transmission characteristic compensation setting operation, and can also flexibly cope with a dynamic change in a transmission path, thereby compensating transmission quality in an optical transmission system. It is an object to provide a method and system.

  A first transmission quality compensation method according to the present invention provides a GMPLS (Generalized Multi-protocol Label) via a control plane provided independently for a data plane formed by an optical communication network including a plurality of nodes and links. Switching quality compensation method for an optical transmission system in which information is communicated from a transmission side to a reception side via the set path after the control means sets a path consisting of a specific node and link based on the switching protocol. A path setting request is given from the control means to the receiving side via the control plane, and an instruction to measure the transmission characteristics of the path is given from the control means to the transmitting side and the receiving side via the control plane. And a transmission characteristic compensation setting instruction for compensating the measured transmission characteristic of the path via the control plane from the control means to the receiving side. The transmission side performs measurement communication via the data plane to the reception side in accordance with a measurement instruction for the transmission characteristic of the path, and the reception side performs the transmission characteristic by the measurement communication. , Execute transmission characteristic compensation setting for compensating transmission characteristics of received information, and communicate a path setting reservation notification from the receiving side to the transmitting side via the control plane to complete the setting. It is characterized by that.

  The second transmission quality compensation method according to the present invention is based on the GMPLS protocol via a control plane provided independently for a data plane formed by an optical communication network including a plurality of nodes and links. After the control means sets a path consisting of a specific node and link, the control means gives an instruction to measure the transmission characteristics of the path through the control plane from the control means to the transmission side and the reception side, and from the control means An instruction of a transmission characteristic compensation setting for compensating the transmission characteristic of the measured path is given to the reception side via the control plane, and the transmission side transmits to the reception side according to the measurement instruction of the transmission characteristic of the path. And the communication for measurement via the data plane, and the reception side measures the transmission characteristic by the measurement communication and transmits the received information. Run the transmission characteristic compensation set for characteristic compensation, and performs communication of information to the receiving side from the transmitting side through the established path.

  The first transmission quality compensation system according to the present invention is based on the GMPLS protocol via a control plane provided independently for a data plane formed by an optical communication network including a plurality of nodes and links. In the optical transmission system in which information is communicated from the transmission side to the reception side via the set path after the control unit sets a path including a specific node and link, the transmission side transmits the path. A communication means for measuring transmission characteristics via the data plane for measuring characteristics, wherein the receiving side receives signals communicated by the communication means for measuring transmission characteristics and measures transmission characteristics A transmission characteristic measuring means, a transmission characteristic compensating means for compensating the transmission characteristic, and a setting means for setting the transmission characteristic in the transmission characteristic compensating means based on the measured transmission characteristic. And the control means makes a path setting request by giving a path setting request to the receiving side via the control plane, and transmits the path setting request to the transmission characteristic measuring communication means and the transmission characteristic measuring means. An instruction for measuring the transmission characteristic of the path is given, a setting instruction for setting the transmission characteristic to the transmission characteristic compensating unit by the setting unit is given to the transmission characteristic measuring unit, and the transmission is performed from the receiving side via the control plane. It is characterized in that the path setting is completed by communicating a path setting securing notification to the side.

  Furthermore, the second transmission quality compensation system according to the present invention is based on the GMPLS protocol via a control plane provided independently of a data plane formed by an optical communication network including a plurality of nodes and links. In the optical transmission system in which information is communicated from the transmission side to the reception side via the set path after the control unit sets a path including a specific node and link, the transmission side transmits the path. A communication means for measuring transmission characteristics via the data plane for measuring characteristics, wherein the receiving side receives signals communicated by the communication means for measuring transmission characteristics and measures transmission characteristics A transmission characteristic measuring means, a transmission characteristic compensating means for compensating the transmission characteristic, and a setting means for setting the transmission characteristic in the transmission characteristic compensating means based on the measured transmission characteristic. The path setting request is made by giving a path setting request from the transmitting side to the receiving side, and a path setting ensuring notification is communicated from the receiving side to the transmitting side via the control plane. Then, after completing the path setting, the control means gives an instruction to measure the transmission characteristic of the path to the communication characteristic measurement communication means and the transmission characteristic measurement means via the control plane, and the transmission A transmission characteristic setting instruction to the transmission characteristic compensation unit by the setting unit is given to the characteristic measurement unit, and information is communicated from the transmission side to the reception side through the set path. And

  According to the present invention, accompanying a series of path setting operations on the GMPLS control plane, a path transmission characteristic measurement instruction and a transmission characteristic compensation setting instruction for compensating the measured path transmission characteristic are provided. And performing communication for measurement via the data plane according to the measurement instruction of the transmission characteristic of the path, and measuring the transmission characteristic based on this and transmission characteristic for compensating the transmission characteristic of the received information Since compensation setting is executed, the transmission characteristic compensation setting operation is completed by an operation on the control plane prior to the start of data communication via the data plane. Therefore, even in a network where the topology changes dynamically, such as an all-optical network instead of a fixed network, high-speed transmission characteristics compensation setting operation is possible, and the dynamic change of the transmission path can be flexibly handled. can do.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
FIG. 1 is a diagram showing a configuration of an optical transmission system to which the present invention is applied.

  The transmitting station 1 and the receiving station 2 are connected via an optical communication network 3. The optical communication network 3 includes edge nodes 4a and 4b, relay nodes 5a and 5b, and links 6a to 6f made of optical fibers interconnecting them, and information to be transmitted is transmitted at a high speed of 40 Gbit / s, for example. The data plane D is configured. Each of the edge nodes 4a and 4b and the relay nodes 5a and 5b includes an optical cross connect (PXC).

  The transmitting station 1, the receiving station 2, and the nodes 4a, 4b, 5a, and 5b are given instructions for path setting and transmission characteristic measurement from the controllers 7a to 7f as control means. The controllers 7a to 7b are interconnected via a hub or the like, for example, and constitute a control plane C that performs mutual communication independently of the data plane D.

  In this embodiment, the path setting operation on the control plane C can be performed based on an RSVP-TE (Resource Reservation Protocol-Traffic Engineering) message used in GMPLS signaling. As is well known, MPLS has fixed-length label information separately from the original destination address of the packet, and transfers the packet based on this label information. Each node 4a, 4b, 5a, 5b holds a label table indicating the relationship between the output label and the output interface (IF) with respect to the input label and the input interface (IF). The next transfer destination node is determined based on the label, not the destination, and the label of the received packet is rewritten and transferred to the next transfer destination node. By repeating this from the transmission unit to the reception unit, packet data is transmitted along the set path.

  Paths are sequentially set in a hop-by-hop manner from the start point to the end point for nodes on the path to be established.

  FIG. 2 is a block diagram showing a main part of the optical transmission system according to the first embodiment of the present invention.

  In the figure, the transmission station 1 includes a transmission device 11 and a transmission characteristic measurement transmitter 12. The transmission characteristic measurement transmitter 12 outputs, for example, a sinusoidal transmission characteristic measurement signal based on a transmission characteristic measurement signal transmission instruction output from the controller 7a when setting a path.

  In addition to the receiving device 21, the receiving station 2 receives a transmission characteristic compensator 22 that performs a compensation operation of received information based on the set transmission characteristic, and a transmission characteristic measurement signal. A transmission characteristic measuring receiver 23 for measuring a transmission characteristic, for example, a chromatic dispersion value from the characteristic measurement signal, and a control unit 24 for setting the transmission characteristic compensator 22 based on the measured value of the transmission characteristic measuring receiver 23; I have. As the transmission characteristic compensator 22, for example, one that switches and uses a plurality of fiber Bragg gratings (FBGs) having different wavelength dispersion characteristics can be used. The transmission characteristic measurement receiver 23 receives a transmission characteristic measurement signal based on channel information for path setting supplied from the controller 7f via the control plane C. The channel information includes, for example, a channel number (wavelength) and a bit rate.

  Next, the path setting operation and the transmission characteristic compensation operation of the optical transmission system configured as described above will be described.

  FIG. 3 is a diagram showing a message flow between nodes at the time of path setting, and FIG. 4 is a flowchart in the controllers 7a and 7f, the transmitting station 1 and the receiving station 2, and both arrows are on the control plane C. The white arrow indicates the flow of data on the data plane D.

  First, when the controller 7a on the transmission side inputs a path setting request (S11), the controller 7a makes a path setting request with channel information by an RSVP-PATH message (S12).

  FIG. 5 shows an example of the RSVP-Path message. The RSVP-Path message is formed by Common header, “Session” Object, “Message ID” Object, “Explicit Route” Object, “Sender TSpec” Object, etc., but the channel information (CH-info ) Can be embedded. That is, “Sender TSpec” has a Fragment for each service. Fragment has multiple parameters. For example, Parameter # 127 has a field called “peak_data_rate” where the bit rate is written. Also, the WDM channel information is written in any Parameter number, for example.

  Based on the GMPLS protocol, the RSVP-Path message is sequentially transferred to the controller of the transmitting station 1, the edge node 4a, the relay node 5a, the edge node 4b, and the receiving station 2 as shown in FIG. Path establishment is performed sequentially. When the path establishment operation at each node is completed by extending the GMPLS protocol, the controller 7a outputs a transmission characteristic compensation operation start instruction to the transmitting station 1 (S13). In response to this, the transmission characteristic measurement transmitter 12 transmits the transmission characteristic measurement signal to the receiving station 2 through the path in which the data plane D is set (S21).

  On the other hand, when the controller 7f receives the path setting request (RSVP-PATH) (S41), the controller 7f extracts the channel information contained therein and notifies the transmission characteristic measurement receiver 23 of the receiving station 2 together with the transmission characteristics. A compensation start instruction is output (S42). Thereby, the transmission characteristic measuring receiver 23 receives the measurement signal of the bit rate specified by the specified WDM channel, and measures the transmission characteristics such as the chromatic dispersion value from the received signal. Further, the control unit 24 sets a reverse characteristic to the measured transmission characteristic in the transmission characteristic compensator 22 (S31). When the setting operation to the transmission characteristic compensator 22 is completed, the control unit 24 sends a setting completion notification to the controller 7f (S32), and the controller 7f receiving the notification outputs a path setting ensuring notification (RSVP-RESV). (S43). The period from the reception of the path setting request at the receiving station 2 to the output of the path setting securing notification is a period for securing the physical characteristics of the data plane D.

  The path setting reservation notification (RSVP-Resv.) Output from the receiving station 2 is sequentially sent to each controller of the receiving station 2 → edge node 4b → relay node 5a → edge node 4a → transmitting station 1 as shown in FIG. When the controller 7a receives the path setting reservation notification, data communication via the data plane D is started (S15).

  According to this embodiment, as shown in FIG. 3, the time from the output of the path setting request in the transmitting station 1 to the reception of the path setting securing notification is the time for securing the path setting. Since the reservation is performed, the setting time for transmission quality compensation can be shortened, and since it is performed at the time of path setting prior to data communication, quality assurance is always performed at the start of data communication. The present invention adds to the control flow using the GMPLS protocol a flow of a new chromatic dispersion measurement and a flow of notifying the transmission characteristic compensator of the inverse characteristic of the measured chromatic dispersion compensation value to form a series of flows. Therefore, it is possible to guarantee the quality of the wavelength path when setting a wavelength path of 40 Gbit / s or more, which was difficult with the wavelength path setting by the conventional GMPLS protocol.

Furthermore, since the above process is an extension of GMPLS signaling, it can be realized without using a new protocol.

[Second Embodiment]
FIG. 6 is a diagram illustrating a message flow between nodes when a path is set in the optical transmission system according to the second embodiment of the present invention.

This embodiment differs from the first embodiment immediately after the path setting ensuring operation by the path setting request from the transmitting station 1 to the receiving station 2 and the path setting ensuring notification from the receiving station 2 to the transmitting station 1. The operation of securing the physical characteristics of the data plane D is performed. In this case, after setting the path, it is set to Administrative Status Testing Mode (monitoring state test mode) which is the monitoring mode of the communication device, the measurement and the characteristic compensation operation are executed, and the data plane setup completion notification is received from the receiving station 2 When the data is transferred to the transmitting station 1, the administrative status testing mode (monitoring status test mode) is canceled. Thereafter, the communication service is established.
[Third Embodiment]
FIG. 7 is a diagram illustrating a configuration of a main part of an optical transmission system according to the third embodiment of the present invention.

  In this embodiment, the case where the transmission part 30 and the receiving part 40 are installed in the user's house is assumed. In this case, the transmission characteristic measurement transmitter 12 is installed at the transmission-side edge node 50a, and the transmission characteristic measurement receiver 23 is installed at the reception-side edge node 50b. In this way, by installing transmission characteristic measuring transceivers in the edge nodes 50a and 50b, these transceivers can be shared and used in many paths through the edge nodes 50a and 50b. The access lines 8a and 8b that connect the edge nodes 50a and 50b to the transmitter 30 and the receiver 40, respectively, usually have a short distance. Also, once the line is laid, the line hardly changes. Furthermore, the optical fiber parameters are very small because the change with temperature is also short. Therefore, the data at the time of line construction can be used as it is.

At the time of path setting, transmission characteristics similar to those described above are measured for the edge nodes 50a to 50b. The measurement result is notified to the receiving unit 40 in which the transmission characteristic compensator 22 is installed via the controllers 7e and 7f. For the access lines 8a and 8b, for example, as shown in FIG. 8, a relationship table of wavelength and core line (access line) number of chromatic dispersion measured in advance is provided in one of the controllers. The chromatic dispersion value is read from the wavelength data to be transmitted, and this is notified to the receiving unit 50 which is the compensation device node. The receiving unit 50 calculates the chromatic dispersion value on the path based on the notified value. An optimum compensation value is obtained from the calculated value and set in the transmission characteristic compensator 22. After the compensation operation is completed, the path setting is completed.
[Fourth Embodiment]
FIG. 9 is a block diagram showing a main part of an optical transmission system according to the fourth embodiment of the present invention.

  In this embodiment, in addition to the transmission characteristic measurement receiver 23, the transmission measurement compensator 22 and the control unit 24 are also installed in the edge node 70 and not installed in the reception unit 60. Is different. In this case, the transmission characteristic compensator 22 is set with a compensation value that also considers chromatic dispersion in the access line 8b.

  As described above, according to the optical transmission system of the present embodiment, by using the GMPLS control plane, transmission characteristic measurement and setting of the measured transmission characteristic to the compensator are performed, so that the wavelength path setting by the GMPLS protocol has been performed so far. Although quality assurance at the time was difficult, according to the present invention, quality assurance can be performed for chromatic dispersion indispensable for a wavelength path of 40 Gbit / s or more.

It is a figure which shows the structure of the optical transmission system with which this invention is applied. It is a block diagram which shows the principal part of the optical transmission system which concerns on the 1st Embodiment of this invention. It is a figure which shows the flow of the message between each node at the time of the path | pass setting in the same system. It is a flowchart which shows a process of a controller, a transmission station, and a receiving station. It is a figure which shows the detail of the RSVP message used with the system. It is a figure which shows the flow of the message between each node at the time of the path | pass setup in the optical transmission system concerning the 2nd Embodiment of this invention. It is a block diagram which shows the principal part of the optical transmission system which concerns on the 3rd Embodiment of this invention. It is a figure which shows the chromatic dispersion data table of the access line in the system. It is a block diagram which shows the principal part of the optical transmission system which concerns on the 4th Embodiment of this invention.

DESCRIPTION OF SYMBOLS 1 ... Transmission station 2 ... Reception station 3 ... Optical communication network 4a, 4b, 50a, 50b, 70 ... Edge node 5a, 5b ... Relay node 6a-6f ... Link 7a-7f ... Controller 8a, 8b ... Access line 11 ... Transmission Device 12 ... Transmitter for measuring transmission characteristics 21 ... Receiving device 22 ... Compensator for transmitting characteristics 23 ... Receiver for measuring transmission characteristics 24 ... Control unit 30 ... Transmitting unit 40, 60 ... Receiving unit

Claims (10)

After the control means sets a path consisting of a specific node and link based on the GMPLS protocol via a control plane provided independently for a data plane formed by an optical communication network consisting of a plurality of nodes and links In the transmission quality compensation method of the optical transmission system for communicating information from the transmission side to the reception side via the set path,
A path setting request is given from the control means to the receiving side via the control plane, and a measurement instruction of transmission characteristics of the path is given from the control means to the transmitting side and the receiving side via the control plane, Giving an instruction of transmission characteristic compensation setting for compensating the transmission characteristic of the measured path from the control means to the reception side via the control plane;
The transmission side performs measurement communication via the data plane to the reception side according to the measurement instruction of the transmission characteristics of the path,
The reception side measures the transmission characteristic by the communication for measurement, executes transmission characteristic compensation setting for transmission characteristic compensation of received information, and the transmission side from the reception side via the control plane A transmission quality compensation method comprising: completing a setting by communicating a path setting reservation notification to After the control means sets a path consisting of a specific node and link based on the GMPLS protocol via a control plane provided independently for a data plane formed by an optical communication network consisting of a plurality of nodes and links ,
An instruction to measure the transmission characteristics of the path is given from the control means to the transmitting side and the receiving side via the control plane, and the measured path is transmitted from the control means to the receiving side via the control plane. Gives instructions for transmission characteristic compensation settings to compensate the characteristics,
The transmission side performs measurement communication via the data plane to the reception side according to the measurement instruction of the transmission characteristics of the path,
On the receiving side, the transmission characteristic is measured by the measurement communication, the transmission characteristic compensation setting for the transmission characteristic compensation of the received information is executed,
A transmission quality compensation method for an optical transmission system for communicating information from a transmission side to a reception side via the set path. The path setting is performed by giving a path setting request from the control means to the receiving side via the control plane,
The transmission quality compensation method according to claim 1 or 2, wherein channel information including a channel number (wavelength) and bit rate information of a path to be set is added to the path setting request.   2. The measurement communication is performed by a signal output from the transmission device on the transmission side, and the measurement of the transmission characteristics and the transmission characteristic compensation are performed on the reception device on the reception side. 4. The transmission quality compensation method according to any one of items 1 to 3.   The measurement communication is performed by a signal output from the edge node on the transmission side, and the transmission characteristic measurement and the transmission characteristic compensation are performed by calculating a chromatic dispersion of a wavelength to be used from a pre-measured chromatic dispersion table. 4. The transmission quality compensation method according to claim 1, wherein the transmission quality compensation is performed at the edge node on the receiving side. After the control means sets a path consisting of a specific node and link based on the GMPLS protocol via a control plane provided independently for a data plane formed by an optical communication network consisting of a plurality of nodes and links In the optical transmission system that performs communication of information from the transmission side to the reception side via the set path,
The transmission side has a communication means for measuring transmission characteristics via the data plane for measuring transmission characteristics of the path,
The receiving side receives a signal communicated by the transmission characteristic measurement communication means and measures the transmission characteristic, a transmission characteristic compensation means for compensating the transmission characteristic, and the measured transmission characteristic And setting means for setting transmission characteristics to the transmission characteristic compensation means based on
The control means makes a path setting request by giving a path setting request to the receiving side via the control plane, and transmits the path transmission characteristics to the transmission characteristic measuring communication means and the transmission characteristic measuring means. And a setting instruction of the transmission characteristic to the transmission characteristic compensation means by the setting means to the transmission characteristic measuring means, and path setting from the receiving side to the transmitting side via the control plane An optical transmission system that completes path setting by communicating a reservation notification. After the control means sets a path consisting of a specific node and link based on the GMPLS protocol via a control plane provided independently for a data plane formed by an optical communication network consisting of a plurality of nodes and links In the optical transmission system that performs communication of information from the transmission side to the reception side via the set path,
The transmission side has a communication means for measuring transmission characteristics via the data plane for measuring the transmission characteristics of the path,
The receiving side receives a signal communicated by the transmission characteristic measurement communication means and measures the transmission characteristic, a transmission characteristic compensation means for compensating the transmission characteristic, and the measured transmission characteristic And setting means for setting transmission characteristics to the transmission characteristic compensation means based on
The path setting request is made by giving a path setting request from the transmitting side to the receiving side, and a path setting ensuring notification is communicated from the receiving side to the transmitting side via the control plane. After completing the settings,
The control means gives an instruction to measure the transmission characteristic of the path to the transmission characteristic measurement communication means and the transmission characteristic measurement means via the control plane, and the transmission characteristic by the setting means to the transmission characteristic measurement means. An optical transmission system characterized in that a transmission characteristic setting instruction is given to the compensation means, and information is communicated from the transmitting side to the receiving side via the set path. The control means performs the path setting request by giving a path setting request to the receiving side via the control plane,
8. The optical transmission system according to claim 6, wherein channel information including a channel number (wavelength) and bit rate information of a path to be set is added to the path setting request.   The transmission characteristic measurement communication means is provided in the transmission device on the transmission side, and the transmission characteristic measurement means and the transmission characteristic compensation means are provided in the reception device on the reception side. The optical transmission system according to claim 6. The transmission characteristic measurement communication means is provided in the measurement-side edge node, and the transmission characteristic measurement means and the transmission characteristic compensation means are provided in the reception-side edge node and are measured in advance. 9. The optical transmission system according to claim 6, wherein the transmission characteristic is measured and the transmission characteristic compensation is performed by extracting chromatic dispersion of a wavelength to be used from a dispersion table.

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