JP3885727B2 - Control path establishment method and system in WDM ring network - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control path establishment method and system in a WDM ring.
[0002]
[Prior art]
The data communication network uses an optical ring network in which multiple nodes are connected to a double ring via two optical fibers, and a bidirectional communication path is used with clockwise and counterclockwise optical fibers. It is possible and high reliability is ensured, and in order to cope with further increase in traffic, a WDM (Wavelength Division Multiplexing) ring network that multiplexes and transmits a plurality of optical signals having different wavelengths. Research and practical application are being made.
[0003]
In a WDM ring network system, an optical signal having a specific wavelength among wavelength multiplexed signals composed of a plurality of optical signals having different wavelengths is separated (received), inserted (multiplexed), and passed in wavelength units. A plurality of node devices each including an OADM (Optical Add Drop Multiplexing) unit having a function (separation unit, insertion unit) capable of performing the above operation are connected in a ring form with a double optical fiber. In the OADM unit in which the wavelength is switched, the optical signal having the wavelength set by the control unit or the like is separated by the separation unit, the optical signal is inserted by the insertion unit, and the wavelength is multiplexed and transmitted to the WDM ring, or Then, control for allowing the input optical signal to pass through without separation is performed. As for a WDM ring network, there has been proposed a system and method that can set a mesh path to be efficiently and surely used only by using a minimum number of wavelengths between a plurality of nodes (see, for example, Patent Document 1). Further, several documents are referred to regarding the configuration of the WDM ring OADM device. For example, in wavelength switching, a network system and a node device have been proposed that have a small propagation delay and a low communication failure rate due to failure / congestion (see, for example, Patent Document 2). Alternatively, even when a large number of nodes (nodes having an OADM device) are provided, a system for reducing the degree of increase of necessary devices for each wavelength and simplifying the configuration has been proposed (for example, (See Patent Document 3).
[0004]
In a WDM ring network system in which a plurality of node devices each having an OADM device are arranged in a double ring, each node device is connected to an IP (Internet Protocol) network, and the WDM ring network system is used as a network for transmitting IP packets. The system to be used is being studied. For example, a WDM ring network is used as a backbone for connecting a plurality of areas, and a packet input from a router in one area to a node device in the WDM ring network depends on the node device connected to the router in the destination area. The wavelength is specified, and the packet is transmitted to the node device in the WDM ring, separated (dropped) by the node device, and transmitted from the node device to the router in the destination area outside the WDM ring. Consider the configured system.
[0005]
In this system, when the node device does not include a relay device such as a router, the wavelength for packet transmission is selected according to the output path of the WDM ring (node device connected to the destination area).
[0006]
On the other hand, a plurality of node devices each including an OADM device and a relay device such as a router that is connected to a packet switching network outside the ring and relays or performs route selection processing in units of packets are arranged in a double ring shape to provide a WDM ring. When a network system is configured, each node device on the WDM ring network can also be a target of route selection processing (routing).
[0007]
[Patent Document 1]
JP 2001-103081 A (3rd to 4th pages, FIG. 1)
[Patent Document 2]
JP-A-9-261259 (pages 4-6, FIG. 1)
[Patent Document 3]
Japanese Patent Laid-Open No. 2001-160785 (pages 4 to 5, FIGS. 1 and 2)
[0008]
[Problems to be solved by the invention]
As a method for establishing a control path in a WDM ring network system, (a) one wavelength is fixedly used in all node devices on the WDM ring, and (b) all node devices on the WDM ring are connected to the WDM ring. Separately, connect with another line such as Ethernet (registered trademark),
Etc. can be used.
[0009]
This control path is used for, for example, wavelength setting / management in a plurality of node devices on the WDM ring. The data path is an IGP (Interior Gateway Protocol) and link state type (topology database called “Shortest Path tree” that exchanges network information connected between routers and routes its device based on that information. Routing protocol OSPF (Open Shortest Path First), RSVP (Resource ReserVation Protocol), which is a signaling protocol that reserves the bandwidth of IP datagrams at all routers before starting communication, data transmission Used for etc.
[0010]
However, in the method (a), one wavelength is occupied for the control data.
[0011]
In the method (b), it is necessary to physically wire each node device by Ethernet (registered trademark) in addition to the double ring.
[0012]
Therefore, it is conceivable to use a method in which the wavelength used in the data path is also used in the control path and the wavelength of the data path and the control path is shared. In this case, there is not much problem in operation in a system in which the data path is hardly changed.
[0013]
However, in a WDM ring network system that shares the wavelength of the data path and the control path and dynamically changes the wavelength for separation and multiplexing (insertion), the control path is interrupted between all the node devices on the WDM ring. And must be able to communicate.
[0014]
Therefore, the problem to be solved by the present invention is to share the wavelength of the data path and the control path in the WDM ring, and to dynamically change the wavelength to be separated and multiplexed, between all the node devices on the ring. It is an object of the present invention to provide a system and a node device that can communicate without interruption of a control path.
[0015]
[Means for Solving the Problems]
A method according to one aspect of the present invention that provides means for solving the above-described problem is a method of separating, inserting (multiplexing), and passing optical signals in units of wavelengths, and separating, multiplexing, and passing optical signals. In a WDM ring network in which a plurality of node devices each having a variable wavelength OADM and a relay device that performs packet relay processing are connected in a ring form, the wavelengths of the control path and the data path between the node devices are separated. First, the wavelength of the data path is used as much as possible as the control path, and the control path is dynamically changed according to the change of the data path.
[0016]
A system according to one aspect of the present invention that provides means for solving the above-described problem is a method of separating, inserting (multiplexing), and passing optical signals in units of wavelengths, and separating, multiplexing, and passing optical signals. In a WDM ring network in which a plurality of node devices each having an OADM having a variable wavelength are connected in a ring form, the wavelength of the data path is not divided into the control path and the data path between the node devices. And a means for dynamically changing the control path according to the change of the data path.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described. The present invention relates to a WDM ring system in which a plurality of node devices each having a combination of an OADM capable of separating, multiplexing and passing optical signals in units of wavelengths and a router capable of routing in units of packets are arranged on a double ring. However, the wavelength of the data path is used as much as possible as the control path without dividing the wavelength of the control path and the data path between the node devices, and the control path is dynamically changed according to the change of the data path. By doing so, each node device can effectively utilize the bandwidth of the WDM ring.
[0018]
In the present invention, one node device on the WDM ring uses a predetermined wavelength (fixed wavelength) in order to know the connection state of a plurality of node devices on the WDM ring. Requesting notification of address information to all node devices (S1, S2 in FIG. 4);
When the one node device receives address information from each of the node devices on the WDM ring, the step of grasping the connection status of each of the plurality of node devices on the WDM ring (S3 in FIG. 4);
One node device that has received a data path setting request from a control terminal connected to the WDM ring establishes a control path with another node device in response to the control path change accompanying the data path setting. Performing steps (S4, S5 in FIG. 4);
A step in which one node device establishes a data path with another node device (S6 in FIG. 4);
including.
[0019]
In the present invention, in order to enable transmission / reception of control data immediately after activation of the node device, the initial value of the wavelength used in the control path is unified in all node devices on the WDM ring and communicates with the control terminal. When a node device establishes a data path, it determines a control path from the wavelength for transferring user data used by each node device, and when the same wavelength is used between adjacent node devices. When a control path is assigned to the wavelength and the same wavelength is not used between adjacent node devices, control is performed using the same wavelength as that of the adjacent node device.
[0020]
In the present invention, when the same wavelength is not found between node devices, a wavelength for transferring only control data is newly added in one node device.
[0021]
In the present invention, when a data path setting request is received from the control terminal (17 in FIG. 2), one node device calculates an optimal control path between all the node devices, and sends the control path to the other node devices. As well as information on the wavelength to be used as well as adjacent node devices.
[0022]
In the present invention, when the one node device receives a path reception response from the other node device, it transmits a path setting request to the other node device, and sets a new control path for all the node devices. Complete the configuration.
[0023]
In the present invention, when a new control path is established, in order to release the control path that was used before receiving the path setting request, the one node device is connected to the other node device. Send a path release request.
[0024]
In the present invention, the other node devices release the wavelengths of the control paths that have been used so far, and issue an opening completion notification to the one node device.
[0025]
In the present invention, when the node device transmits control data to the WDM ring, it searches the output ring search table from the destination address of the packet storing the control data, It is good also as a structure provided with the means to select either a ring or an inner ring.
[0026]
【Example】
In order to describe the above-described embodiment of the present invention in more detail, examples of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing the system configuration of the first embodiment of the present invention. This network is configured by connecting a plurality of node devices each having an OADM and a router in a ring shape. Each of the node devices 1, 5, 9, and 13 includes OADMs 2, 6, 10, and 14 and routers 3, 7, 11, and 15. In FIG. 1, four node devices are shown as an example, but the present invention is of course not limited to such a number.
[0027]
Between each node device, two optical fibers of an inner ring (Inner Ring) 21 and an outer ring (Outer Ring) 22 are connected to form a double WDM ring as a whole.
[0028]
The node devices 1, 5, 9, and 13 are connected to IP networks 4, 8, 12, and 16 via routers 3, 7, 11, and 15, respectively.
[0029]
FIG. 2 is a diagram showing an example of the configuration of the first embodiment of the present invention. Referring to FIG. 2, the OADMs 2, 6, 9, and 14 of the node devices 1, 5, 9, and 13 are respectively connected to the OADMs 2, 6, 10, and 14 of the adjacent node devices 1, 5, 9, and 13, respectively. Connected by optical fibers, the optical signals of the inner ring (Inner Ring) 21 and the outer ring (Outer Ring) 22 are separated, multiplexed, and passed in wavelength units, respectively. In this embodiment, the wavelength of the optical signal that is separated and multiplexed by the OADM is variable, and can be arbitrarily selected from all wavelengths on the WDM ring.
[0030]
Routers 3, 7, 11, and 15 route optical signals separated from OADMs 2, 6, 10, and 14 in units of IP packets, and multiplex IP packets from the IP network to wavelengths on the WDM ring. In order to do this, the data is transferred to OADMs 2, 6, 10, and 14.
[0031]
By changing the data path using an arbitrary wavelength, load distribution of user data is performed and operability is improved by remotely operating all node devices on the WDM ring from one control terminal 17 In order to achieve this, it is necessary to transmit and receive control data between all node devices on the WDM ring.
[0032]
As control data,
-Node device connection information on the WDM ring,
-Wavelength information used for communication with adjacent node devices,
-Control path and data path setting information
and so on.
[0033]
The control terminal 17 transmits and receives control data to and from the node device 1 in order to set paths for all the node devices 1, 5, 9, and 13 on the WDM ring. The control terminal 17 does not necessarily need to be physically directly connected to the node device 1 on the WDM ring, and may be present on a network that can communicate with the node device 1 on the WDM ring.
[0034]
FIG. 3 is a diagram showing the configuration of the node device in the first exemplary embodiment of the present invention. The node device corresponds to each wavelength separated by the variable wavelength separation unit 100 and the variable wavelength separation unit 100 that separates the wavelengths of a plurality of wavelength-multiplexed optical signals for the inner ring. The optical receiver 102 and the variable wavelength transmitter 103,..., The optical receiver 104 and the variable wavelength optical transmitter 105, the output from the variable wavelength separator 100, the variable wavelength optical transmitter 103,. A wavelength multiplexing unit 101 that multiplexes outputs from the unit 105 is provided. As for the outer ring (OuterRing), the OADM unit includes a variable wavelength separation unit 116 that separates wavelengths, an optical reception unit 112 corresponding to each wavelength separated by the variable wavelength separation unit 116, and a variable wavelength optical transmission unit 113,. A set of an optical receiver 114 and a variable wavelength optical transmitter 115, and a wavelength multiplexing unit 117 that multiplexes the output from the variable wavelength separator 116 and the output of the variable wavelength optical transmitter 113,. ing.
[0035]
The router includes a control unit 111 connected to a control terminal (17 in FIG. 2), a layer processing unit 106 that receives and transmits signals between the optical receiving unit 102 and the variable wavelength optical transmitting unit 103, and an optical receiving unit 104. A layer processing unit 107 that receives and transmits a signal between the optical wavelength transmission unit 105 and the variable wavelength optical transmission unit 105, a layer processing unit 109 that receives and transmits a signal between the optical reception unit 112 and the variable wavelength optical transmission unit 113, A layer processing unit 110 that receives and transmits signals between the optical receiving unit 114 and the variable wavelength optical transmitting unit 115, a plurality of line interfaces 120,... 121 that control line connection with the IP network, and a plurality of line interfaces 120,... 121 connected to the layer processing unit 118,... 119 connected to the control unit 111 and the control unit 111, and the layer processing connected via each port. And a, a switch unit 108 for switching queuing signals with the 106,107,109,110,118,119. The switch unit 108 of the router performs processing for determining the destination network from the destination address in the header of the IP packet, resolving the output route based on the routing table, and outputting it to the relay destination port.
[0036]
In the variable wavelength demultiplexing unit 100 or 116, based on the wavelength selection signal from the control unit 111, only the wavelength specified by the control unit 111 is obtained from the optical signal received from the inner ring (Outer Ring) or the outer ring (Outer Ring). Separate and allow other wavelengths to pass.
[0037]
The separated optical signals are converted into electric signals by the optical receiving units 102, 104, 112, and 114.
[0038]
The layer processing units 106, 107, 109, and 110 process the layer 1, layer 2, layer 3, and further layers on the electrical signals converted by the optical receiving units 102, 104, 112, and 114. I do. The layer processing units 118 and 119 also perform layer processing of layer 2 (data link layer), layer 3 (network layer), or higher.
[0039]
As described above, the switch unit 108 resolves the output route based on the destination address of the IP packet and transfers the IP packet.
[0040]
The variable wavelength light transmitters 103, 105, 113, and 115 receive the electrical signals from the layer processors 106, 107, 109, and 110, convert them into optical signals having wavelengths specified by the controller 111, and transmit them.
[0041]
The wavelength multiplexing unit 101 multiplexes the optical signal that passes through and the optical signal received from the variable wavelength optical transmission units 103,..., 105, and transmits them to the inner ring.
[0042]
The wavelength multiplexing unit 117 multiplexes the optical signal that passes through and the optical signal received from the variable wavelength optical transmission units 113,... 115, and transmits the multiplexed signal to the outer ring.
[0043]
In this OADM, for example, an optical signal (for example, wavelength λ1) obtained by separating the wavelength-multiplexed optical signal received from the inner ring by the variable wavelength demultiplexing unit 100 is received by the optical receiving unit 102, and the layer processing unit 106 is In the case of being addressed to the IP network and destined for the IP network, the routing port is selected by referring to the routing table to determine the relay port, and the IP packet is transmitted from the relay port to the destination network node. On the other hand, the switch unit 108 that has received an IP packet from the IP network via the line interface (120/121) and the layer processing unit (118/119) selects a route from the destination address of the header of the IP packet, The output port corresponding to the output route of the corresponding route is determined (the output port connected to the variable wavelength optical transmission unit that outputs the wavelength for transmission to the destination node device via the layer processing unit), and the port The IP packet is output from and transmitted to the inner or outer ring via the layer processing unit, the variable length optical transmission unit, and the wavelength multiplexing unit.
[0044]
In this OADM, when switching wavelengths, the optical signal (for example, wavelength λ1) separated by the variable wavelength separation unit 100 is received by the optical reception unit corresponding to the wavelength, and is switched via the switch unit 108. For example, the signal is transmitted from the wavelength multiplexing unit 101 via the variable length optical transmission unit corresponding to the wavelength (for example, λ2). When the wavelength-multiplexed optical signal is allowed to pass through without being dropped, control is performed to pass through the variable wavelength demultiplexing unit 100 and the wavelength multiplexing unit 101 as they are.
[0045]
Further, in this OADM, the control unit 111 that has received a control signal (for example, path setting, wavelength change, etc.) from the control terminal (17 in FIG. 2) creates a control packet and transmits it to the switch unit 108. A control packet is transmitted from the switch unit 108 to the next node device at a predetermined wavelength via, for example, a layer processing unit, a variable-length optical transmission unit, and a wavelength multiplexing unit (for example, 101).
[0046]
Next, the operation of the first embodiment of the present invention will be described. FIG. 4 is a flowchart showing the operation of the node device 1 (see FIG. 2) when a user data path setting request is received from the control terminal 17 (see FIG. 2). However, the operation illustrated in FIG. 4 is a series of operations from the activation of all the node devices 1, 5, 9, and 13 on the WDM ring to the completion of data path setting in FIG.
[0047]
In order to know the connection status of all the node devices 1, 5, 9, and 13 on the WDM ring, request notification of address information to all the node devices on the WDM ring using a predetermined specific wavelength. (Step S1). The address information corresponds to a MAC (Media Access Control) address of Ethernet (registered trademark).
[0048]
When address information is received from all the node devices 1, 5, 9, and 13 (YES in step S2), the connection status of all the node devices 1, 5, 9, and 13 on the WDM ring is grasped (step S3).
[0049]
When there is a data path setting request from the control terminal 17 (YES in step S4), one node device establishes a control path with another node device (step S5).
[0050]
Subsequently, the one node device establishes a data path with another node device (step S6).
[0051]
Referring to FIG. 2, for example, the node device 1 takes the lead and establishes control paths with the other node devices 5, 9, and 13.
[0052]
Next, the establishment of the control path in step S5 in FIG. 4 will be described. FIG. 5 is a diagram schematically illustrating a ring configuration example in units of wavelengths. However, as an example, the wavelengths used in the WDM ring are four waves of λ1, λ2, λ3, and λ4, and the number of node devices is six. Further, the control terminal 17 (corresponding to 17 in FIG. 2) communicates with the node device A and sets the data paths of all the node devices A to F.
[0053]
As for the data path, communication is performed at the same wavelength among all the node devices, and logically, a plurality of rings exist independently for each wavelength.
[0054]
On the other hand, for the control path, a part of the user data wavelength is used, and each node device changes the wavelength (the control path uses a plurality of wavelengths as a whole) to establish a path where all node devices can communicate. To do. However, the same wavelength is used for communication between the node devices. For example, a thick line 501 in FIG. 5 indicates a control path.
[0055]
FIG. 6 schematically shows the control path of FIG. Referring to FIGS. 5 and 6, the control path is
With the node equipment A-C and the node equipment EA, the wavelength λ1,
In the node equipment A-B, the wavelength λ2,
Node device B-D, wavelength λ3,
At the node equipment D-E-F, the wavelength is λ4.
[0056]
The wavelength for transferring control data and user data is
Between the node equipment A-C (excluding B) and the node equipment EA (excluding F), λ1,
Between the node devices A and B, λ2,
Λ3 between node devices B and D (excluding C),
It becomes λ4 between the node devices D-E-F.
[0057]
The node device B transfers only user data at the wavelength λ4, and the node device F transfers only user data at the wavelength λ2.
[0058]
Next, a procedure for establishing a control path in the first embodiment of the present invention will be described. When the node device A receives a data path setting request from the control terminal 17, the node device A determines the control path, and establishes the control paths of the node devices B to F led by the node device A.
[0059]
First, in order to enable transmission / reception of control data immediately after activation of each node device, it is necessary to unify initial values of wavelengths used in the control path in all node devices. The initial state shown in FIG. 7A corresponds to this, and here, the initial value of the wavelength used in the control path is λ1.
[0060]
When establishing a data bus, the node device A communicating with the control terminal 17 determines a control path from the wavelength for transferring user data used in each node device. In the determination process, if the same wavelength is used between adjacent node devices, a control path is assigned to that wavelength, and if the same wavelength is not used between adjacent node devices, the same as the adjacent node device. Use wavelength. If the same wavelength as that of the adjacent node device is not used, the same wavelength as that of the adjacent node device is used. FIG. 7B corresponds to this.
[0061]
Furthermore, if there is a change in the data path setting, the control path is switched in the same procedure as shown in FIGS. 7B to 7C.
[0062]
The wavelength for transferring control data and user data is
Λ4 at the node equipment A-F, λ1 at the node equipment B-C-D-E,
Node device A-C (excluding B), node device EF, λ2
It becomes.
[0063]
The node device B transfers only user data at the wavelength λ3, and the node device D transfers only user data at the wavelengths λ3 and λ4. (See Fig. 7 (c)) .
[0064]
If the same wavelength is not found between the node devices, a wavelength for transferring only control data in one node device is newly added. FIG. 7D corresponds to this. That is, in the node apparatus B, a wavelength λ2 (see ◯ in FIG. 7D) for transferring only control data is added.
[0065]
FIG. 8 is a sequence diagram illustrating an example of a sequence of control data transmitted and received between the control terminal and the node apparatuses A to F in the case where the data path is changed in FIGS. 7A to 7B. . However, on the premise that all the node devices A to F know the connection status based on the address information of all the node devices A to F on the WDM ring, transmission and reception of control data between the node devices It is assumed that either an inner ring or an outer ring may be used.
[0066]
When one node device A on the WDM ring receives a data path setting request from the control terminal 17, the node device A calculates an optimal control path between the node devices A to F on the WDM ring, The other node devices BF on the WDM ring are notified of the wavelength used as a control path and information on adjacent node devices.
[0067]
When the node device A receives a path reception response from the other node devices B to F on the WDM ring, the node device A transmits a path setting request to the other node devices B to F, and all the node devices on the WDM ring The setting of new control paths A to F is completed.
[0068]
At the time when a new control path is established, the node apparatus A makes other node apparatuses B to F open to the control path used before receiving the path setting request from the control terminal 17. Send a path release request.
[0069]
Then, the other node apparatuses B to F release the wavelengths of the control paths that have been used so far, and notify the node apparatus A of the completion of opening.
[0070]
More specifically, referring to FIG. 8, the node device A that has received the data path setting request from the control terminal (17 in FIG. 2) determines an optimal control data path at the time of path setting.
[0071]
(A1) The node device A notifies the node device B of the control path with the wavelength λ1. The content is that node device B is connected to node device A at wavelength λ2, and is connected to node device D at wavelength λ3.
[0072]
(A2) The node device B returns a path reception response to the node device A at the wavelength λ1.
[0073]
(A3) The node device A notifies the node device C of the control path with the wavelength λ1. The content is that node device C is connected to node device A at wavelength λ1.
[0074]
(A4) The node device C returns a path reception response to the node device A at the wavelength λ1.
[0075]
(A5) The node device A notifies the node device D of the control path with the wavelength λ1. The contents are that the node device D is connected to the node device B at the wavelength λ3 and is connected to the node device E at the wavelength λ4.
[0076]
(A6) The node device D returns a path reception response to the node device A at the wavelength λ1.
[0077]
(A7) The node device A notifies the node device E of the control path with the wavelength λ1. The contents are that node device E is connected to node device A at wavelength λ1, connected to node device D at wavelength λ4, and connected to node device F at wavelength λ4.
[0078]
(A8) The node device E returns a path reception response to the node device A at the wavelength λ1.
[0079]
(A9) The node device A notifies the node device F of the control path at the wavelength λ1. The content is that the node device F is connected to the node device E at the wavelength λ4.
[0080]
(A10) The node device F returns a path reception response to the node device A at the wavelength λ1.
[0081]
(A11) The node device A transmits a path setting request to the node device B at the wavelength λ1.
[0082]
(A12) The node device B transmits a path setting response to the node device A with the wavelength λ1.
[0083]
(A13) The node device A transmits a setting completion request to the node device B at the wavelength λ2.
[0084]
(A14) The node device B transmits a switching completion response to the node device A at the wavelength λ2.
[0085]
(A15) The node device A transmits a path setting request to the node device C with the wavelength λ1.
[0086]
(A16) The node device C transmits a path setting response to the node device A at the wavelength λ1.
[0087]
(A17) The node device A transmits a switch completion request to the node device C at the wavelength λ1.
[0088]
(A18) The node device C transmits a switch completion response to the node device A at the wavelength λ1.
[0089]
(A19) The node device A transmits a path setting request to the node device D with the wavelength λ1.
[0090]
(A20) The node device D transmits a path setting response to the node device A at the wavelength λ1.
[0091]
(A21) The node device A transmits a setting completion request to the node device B at the wavelength λ2, the node device B performs wavelength switching, and transmits a setting completion request to the node device D at the wavelength λ3.
[0092]
(A22) The node device D transmits a switching completion response to the node device B at the wavelength λ3, the node device B performs wavelength switching, and transmits a switching completion response to the node device A at the wavelength λ2.
[0093]
(A23) The node device A transmits a path setting request to the node device E with the wavelength λ1.
[0094]
(A24) The node device E transmits a path setting response to the node device A at the wavelength λ1.
[0095]
(A25) The node device A transmits a setting completion request to the node device B at the wavelength λ2, the node device B performs wavelength switching, and transmits a setting completion request to the node device D at the wavelength λ3. D changes the wavelength and transmits a setting completion request to the node apparatus E at the wavelength λ4.
[0096]
(A26) The node device E transmits a switching completion response to the node device D at the wavelength λ4. Upon receipt of this, the node device D performs wavelength switching, and transmits a switching completion response to the node device B at the wavelength λ3. In response to this, the node device B performs wavelength switching, and transmits a switching completion response to the node device A at the wavelength λ2.
[0097]
(A27) The node device A transmits a path setting request to the node device F at the wavelength λ1.
[0098]
(A28) The node device F transmits a path setting response to the node device A at the wavelength λ1.
[0099]
(A29) The node device A transmits a setting completion request to the node device B at the wavelength λ2, and in response to this, the node device B performs wavelength switching and transmits a setting completion request to the node device D at the wavelength λ3. In response to this, the node device D changes the wavelength, transmits a setting completion request to the node device E at the wavelength λ4, and the node device E receives the signal to the node device F at the same wavelength λ4. Send a setting completion request.
[0100]
(A30) The node device F transmits a switching completion response to the node device E at the wavelength λ4. Upon receipt of this, the node device E transmits a switching completion response to the node device D at the wavelength λ4 as it is, and receives this. The node device D changes the wavelength and transmits a switching completion response to the node device B at the wavelength λ3. Upon receipt of this, the node device B changes the wavelength and sends the wavelength change to the node device A at the wavelength λ2. Send a switch completion response.
[0101]
(A31) The node device A transmits a path setting request to the node device E with the wavelength λ1.
[0102]
(A32) The node device E transmits a path setting response to the node device A at the wavelength λ1.
[0103]
(A33) The node device A transmits a setting completion request to the node device E at the wavelength λ1.
[0104]
(A34) The node device E transmits a switching completion response to the node device A at the wavelength λ1.
[0105]
(A35) The node device A transmits a path release request to the node device B at the wavelength λ2.
[0106]
(A36) The node device B transmits a release completion notification to the node device A at the wavelength λ2.
[0107]
(A37) The node device A transmits a path release request to the node device C at the wavelength λ1.
[0108]
(A38) The node device C transmits a release completion notification to the node device A at the wavelength λ1.
[0109]
(A39) The node device A transmits a path opening request to the node device B at the wavelength λ2, the node device B performs wavelength switching, and transmits a path opening request to the node device D at the wavelength λ3.
[0110]
(A40) The node device D transmits a release completion notification to the node device B at the wavelength λ3, the node device B performs wavelength switching, and transmits a release completion notification to the node device A at the wavelength λ2.
[0111]
(A41) The node device A transmits a path release request to the node device B at the wavelength λ2, the node device B performs wavelength switching, and transmits a path release request to the node device D at the wavelength λ3. D performs wavelength switching, and transmits a path release request to the node apparatus E at the wavelength λ4.
[0112]
(A42) The node device E transmits a release completion notification to the node device D at the wavelength λ4, the node device D performs wavelength switching, and transmits a release completion notification to the node device B at the wavelength λ3. B performs wavelength switching and transmits a release completion notice to the node apparatus A at the wavelength λ2.
[0113]
(A43) The node device A transmits a path release request to the node device B at the wavelength λ2, the node device B performs wavelength switching, and transmits a path release request to the node device D at the wavelength λ3. D performs wavelength switching, transmits a path release request to the node apparatus E at the wavelength λ4, and the node apparatus E transmits a path release request to the node apparatus F at the wavelength λ4.
[0114]
(A44) The node device F transmits a release completion notification to the node device E at the wavelength λ4, the node device D transmits a release completion notification to the node device E at the wavelength λ4, and the node device D changes the wavelength The node apparatus B transmits a release completion notification to the node apparatus B at the wavelength λ3, the node apparatus B performs wavelength switching, and transmits an opening completion notification to the node apparatus A at the wavelength λ2.
[0115]
(A45) When the release completion notification is received for all the node devices A, the setting completion notification is transmitted to the control terminal.
[0116]
FIG. 9 is a diagram illustrating details of an operation sequence when a path is changed from the state of FIG. 7B to the state of FIG. 7C. Also in this case, in the same manner as in the sequence shown in FIG. 8, when one node device A on the WDM ring receives a data path setting request from the control terminal 17, this node device A is a node on the WDM ring. The optimum control path between the devices A to F is calculated, and the wavelength used as the control path and information on adjacent node devices are notified to the other node devices B to F on the WDM ring. When the node device A receives a path reception response from the other node devices B to F on the WDM ring, the node device A transmits a path setting request to the other node devices B to F, and all the node devices on the WDM ring The setting of new control paths A to F is completed. At the time when a new control path is established, the node apparatus A makes other node apparatuses B to F open to the control path used before receiving the path setting request from the control terminal 17. Send a path release request. Then, the other node apparatuses B to F release the wavelengths of the control paths that have been used so far, and notify the node apparatus A of the completion of opening.
[0117]
More specifically, referring to FIG. 9, the node device A that has received a data path setting request from the control terminal 17 determines an optimal control data path at the time of path setting.
[0118]
(B1) The node device A notifies the node device B of the control path at the wavelength λ2. The content is that node device B is connected to node device C at wavelength λ1.
[0119]
(B2) The node device B returns a path reception response to the node device A at the wavelength λ2.
[0120]
(B3) The node device A notifies the node device C of the control path with the wavelength λ1. The contents are that node device C is connected to node device A at wavelength λ2, connected to node device B at wavelength λ1, and connected to node device D at wavelength λ1.
[0121]
(B4) The node device C returns a path reception response to the node device A at the wavelength λ1.
[0122]
(B5) The node device A first notifies the node device B of the control path notification to the node device D with the wavelength λ2, and the node device B performs wavelength switching and controls the node device D with the wavelength λ3. Notify the path. The contents are that the node device D is connected to the node device C at the wavelength λ1, and is connected to the node device E at the wavelength λ1.
[0123]
(B6) The node device D returns a path reception response to the node device B at the wavelength λ3, performs wavelength switching at the node device B, and returns a path reception response of the node device D to the node device A at the wavelength λ2. .
[0124]
(B7) The node device A notifies the node device E of the control path to the node device E with the wavelength λ2, and the node device B performs the wavelength change and notifies the node device D with the wavelength λ3. The node device D performs wavelength switching, and the node device E is notified by λ4. The contents are that the node equipment E is connected to the node equipment D at the wavelength λ1, and is connected to the node equipment F at the wavelength λ2.
[0125]
(B8) The path reception response from the node device E is notified to the node device D at the wavelength λ4, the wavelength is changed by the node device D, is notified to the node device B at the wavelength λ3, and the wavelength is transmitted from the node device B. And is returned to the node device A at the wavelength λ2.
[0126]
(B9) The node device A notifies the node device F of the control path notification to the node device F at the wavelength λ2, performs the wavelength change at the node device B, and is notified to the node device D at the wavelength λ3. Then, the wavelength change is performed by the node device D, and the node device F is notified at the wavelength λ4. The contents are that the node device F is connected to the node device A at the wavelength λ4, and is connected to the node device E at the wavelength λ2.
[0127]
(B10) The path reception response from the node device F is notified to the node device D at the wavelength λ4, the wavelength is changed by the node device D, is notified to the node device B at the wavelength λ3, and the wavelength of the wavelength is transmitted from the node device B. Transfer is performed and returned to the node apparatus A at the wavelength λ2.
[0128]
(B11) The node device A transmits a path setting request to the node device C at the wavelength λ1.
[0129]
(B12) The node device C transmits a path setting response to the node device A with the wavelength λ1.
[0130]
(B13) The node device A transmits a setting completion request to the node device C at the wavelength λ2.
[0131]
(B14) The node device C transmits a switch completion response to the node device A at the wavelength λ2.
[0132]
(B15) The node device A transmits a path setting request to the node device B at the wavelength λ2.
[0133]
(B16) The node device B transmits a path setting response to the node device A at the wavelength λ2.
[0134]
(B17) The node device A notifies the node device C of a setting completion request to the node device B, performs wavelength switching at the node device C, and transmits a setting completion request to the node device B at the wavelength λ1. To do.
[0135]
(B18) The node device B transmits a switching completion response to the node device C at the wavelength λ1, performs wavelength switching at the node device C, and transmits a switching completion response for the node device B to the node device A at the wavelength λ2. .
[0136]
(B19) The node device A notifies the node device B of a path setting request to the node device D, performs wavelength switching at the node B, and transmits a path setting request to the node device D at the wavelength λ3. .
[0137]
(B20) The node device D transmits a path setting response to the node device B at the wavelength λ3, performs wavelength switching at the node device B, and transmits a path setting response of the node device D to the node device A at the wavelength λ2. .
[0138]
(B21) The node device A transmits a setting completion request to the node device D to the node device C at the wavelength λ2, the node device C performs wavelength switching, and transmits a setting completion request to the node device D at the wavelength λ1. To do.
[0139]
(B22) The node device D transmits a switching completion response to the node device C at the wavelength λ1, the node device C performs wavelength switching, and transmits a switching completion response of the node device D to the node device A at the wavelength λ2. .
[0140]
(B23) The node device A transmits a path setting request to the node device E to the node device B with the wavelength λ2, the node device B performs wavelength switching, and transmits to the node device D with the wavelength λ3. D performs wavelength switching and transmits it to the node apparatus E at the wavelength λ4.
[0141]
(B24) The node device E transmits a path setting response to the node device D with the wavelength λ4, the node device D performs wavelength switching, transmits it to the node device B with the wavelength λ3, and the node device B performs wavelength switching. And a path setting response from the node device E is transmitted to the node device A at the wavelength λ2.
[0142]
(B25) The node device A transmits a setting completion request to the node device E to the node device C at the wavelength λ2, the node device C performs wavelength switching, and transmits a setting completion request to the node device E at the wavelength λ1. To do.
[0143]
(B26) The node device E transmits a switching completion response to the node device C at the wavelength λ1, and in response to this, the node device C performs wavelength switching, and the node device E switches to the node device A at the wavelength λ2. Send.
[0144]
(B27) The node device A transmits a path setting request to the node device F to the node device B at the wavelength λ2, performs wavelength switching at the node device B that receives the request, and transmits to the node device D at the wavelength λ3. The node device D performs wavelength switching, and transmits to the node device F at the wavelength λ4.
[0145]
(B28) The node device F transmits a path setting response to the node device D at the wavelength λ4, performs wavelength switching at the node device D, transmits to the node device B at the wavelength λ3, and performs wavelength switching at the node device B. And transmitted to node device A at wavelength λ2.
[0146]
(B29) The node device A transmits a setting completion request to the node device F to the node device C at the wavelength λ2, and in response to this, the node device C performs wavelength switching and sets the node device E at the wavelength λ1. In response to the completion request, the node apparatus E performs wavelength switching, and transmits it to the node apparatus F at the wavelength λ2.
[0147]
(B30) The node device F transmits a switching completion response to the node device E at the wavelength λ2, the node device E performs wavelength switching, transmits a switching completion response to the node device C at the wavelength λ1, and receives this. The node device C performs wavelength switching and transmits a node device F switching completion response to the node device A at the wavelength λ2.
[0148]
(B31) The node device A transmits a path setting request to the node device F to the node device E at the wavelength λ1, performs wavelength switching at the node device E that receives the request, and transmits to the node device F at the wavelength λ4. To do.
[0149]
(B32) The node device F transmits a path setting response to the node device E at the wavelength λ4, performs wavelength switching at the node device E, and transmits it to the node device A at the wavelength λ1.
[0150]
(B33) The node device A transmits a switch completion request to the node device F at the wavelength λ4.
[0151]
(B34) The node device F transmits a switch completion response to the node device A at the wavelength λ4.
[0152]
(B35) The node device A transmits a path release request to the node device C at the wavelength λ2.
[0153]
(B36) The node device C transmits a release completion notification to the node device A at the wavelength λ2.
[0154]
(B37) The node device A transmits a path release request to the node device B to the node device C at the wavelength λ2, the node device C performs wavelength switching, and transmits a path release request to the node device B at the wavelength 1. To do.
[0155]
(B38) The node device B transmits a release completion notification to the node device C at the wavelength λ1, performs wavelength switching at the node device C, and transmits a release completion notification to the node device A at the wavelength λ2.
[0156]
(B39) The node device A transmits a path opening request to the node device D to the node device C at the wavelength λ2, the node device C performs wavelength switching, and transmits a path opening request to the node device D at the wavelength λ1. To do.
[0157]
(B40) The node device D transmits a release completion notification to the node device C at the wavelength λ1, performs wavelength switching at the node device C, and transmits a release completion notification to the node device A at the wavelength λ2.
[0158]
(B41) The node device A transmits a path release request to the node device E to the node device C at the wavelength λ2, performs wavelength switching at the node device C, and transmits a path release request to the node device E at the wavelength λ1. To do.
[0159]
(B42) The node device E transmits an opening completion notification to the node device C at the wavelength λ1, performs wavelength switching at the node device C, and transmits an opening completion notification to the node device A at the wavelength λ2.
[0160]
(B43) The node device A transmits a path release request to the node device F to the node device C at the wavelength λ2, performs wavelength switching at the node device C, and transmits to the node device E at the wavelength λ1. E performs wavelength switching and transmits a path release request to the node apparatus F at the wavelength λ2.
[0161]
(B44) The node device F transmits a release completion notification to the node device E at the wavelength λ2, the node device E performs wavelength switching, and transmits a release completion notification of the node E to the node device C at the wavelength λ1. The device C performs wavelength switching and transmits a release completion notification to the node device A at the wavelength λ2.
[0162]
(B45) When the release completion notification is received for all the node devices A, the setting completion notification is transmitted to the control terminal 17.
[0163]
Next, another embodiment of the present invention will be described. FIG. 10 is a diagram illustrating a configuration of a node device according to the second exemplary embodiment of the present invention. Referring to FIG. 10, unlike the first embodiment shown in FIG. 3, the second embodiment includes an output ring search table 122 in the router. In the second embodiment of the present invention, the configuration of the WDM ring is the same as that of the first embodiment described with reference to FIGS. That is, in the second embodiment of the present invention, the configuration other than the output ring search table 122 of the node device is the same as that of the first embodiment. Therefore, hereinafter, the first embodiment shown in FIG. Differences from the example will be described.
[0164]
When the node devices 1, 5, 9, and 13 in FIG. 1 transmit control data to the WDM ring, the router determines the output ring search table 122 (FIG. 10) from the destination address of the IP packet storing the control data. Search), and one of the inner ring (Inner Ring) and the outer ring (Outer Ring) can be selected as an output route.
[0165]
According to this embodiment, the shortest route can be selected from the two rings. Further, when a failure occurs in one ring, the other ring can be selected as a detour.
[0166]
In the above-described embodiment, the description has been given in connection with an example in which an IP router is used as a router. However, the relay device that relays a packet in the present invention is not limited to an IP router, but at the entrance of a router of an IP network. Multi-Protocol Label Switching (MPLS) router that attaches labels and relays packets according to the labels, Layer 2 switch (switching HUB) that performs relay processing based on Layer 2 protocol, ATM (Asynchronous Transfer Mode) switch, frame relay switch It may be.
[0167]
Note that the WDM ring of the above embodiment is not limited to a large-scale network extending over a plurality of areas, but can be applied to a network of any scale. Although the present invention has been described with reference to the above-described embodiments, the present invention is not limited to the configurations of the above-described embodiments, and can be made by those skilled in the art within the scope of the invention of the claims. It goes without saying that various modifications and corrections of the wax are included.
[0168]
【The invention's effect】
As described above, according to the present invention, the wavelength of the data path is used as much as possible as the control path without dividing the wavelength of the control path and the data path between the node devices, and the control is performed according to the change of the data path. Since the path is dynamically changed, each node device can effectively use the bandwidth of the WDM ring in the WDM ring system in which a plurality of node devices are arranged on a double ring.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of the overall configuration of a system according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating an example of an overall configuration of a system according to an embodiment of the present invention.
FIG. 3 is a diagram illustrating a configuration of a node device according to an embodiment of the present invention.
FIG. 4 is a diagram for explaining the operation of the node device according to the embodiment of the present invention.
FIG. 5 is a diagram for explaining an example of a wavelength unit ring configuration according to an embodiment of the present invention;
FIG. 6 is a diagram schematically showing a control path in an embodiment of the present invention.
FIG. 7 is a diagram schematically showing a procedure for establishing a control path in an embodiment of the present invention.
FIG. 8 is a diagram (part 1) illustrating an example of a control path setting sequence in a control terminal and a node device according to an embodiment of the present invention;
FIG. 9 is a diagram (part 2) illustrating an example of a control path setting sequence in the control terminal and the node device according to the embodiment of the present invention.
FIG. 10 is a diagram illustrating a configuration of a node device according to another embodiment of the present invention.
[Explanation of symbols]
1, 5, 9, 13 nodes
2, 6, 10, 14 OADM
3, 7, 11, 15 routers
100 Variable wavelength separation unit
101 Wavelength multiplexing part
102 Optical receiver
103 Variable wavelength optical transmitter
104 Optical receiver
105 Variable wavelength optical transmitter
106 Layer processing unit
107 Layer processing unit
108 Switch part
109 Layer processing unit
110 Layer processing unit
111 Control unit
112 Optical receiver
113 Variable wavelength optical transmitter
114 Optical receiver
115 Variable wavelength optical transmitter
116 Variable wavelength separation unit
117 Wavelength multiplexing part

Claims (22)

Including a plurality of node devices connected by a ring-shaped optical transmission path through which a plurality of optical signals having different wavelengths are multiplexed and transmitted;
The node device inputs and outputs a wavelength-multiplexed optical signal transmitted to the optical transmission line, and separates, inserts, or passes the optical signal in units of wavelength, and performs separation, insertion, and passage. An OADM (Optical AddDrop Multiplexing) device in which the wavelength of the light is variable,
A relay device that is connected to a network outside the ring and the OADM, and performs packet relay processing;
A control path establishment method for a WDM (Wavelength Division Multiplexing) ring network, comprising:
Using the wavelength of the data path as much as possible as the control path without dividing the wavelength of the control path and the data path between the node devices on the WDM ring;
A node device on a WDM ring dynamically changing the control path in response to the setting change of the data path;
Only including,
At least one node device that communicates with a control terminal among a plurality of node devices on the WDM ring is controlled from a wavelength for transferring user data used in each node device on the WDM ring when establishing a data path. When a path is determined and the same wavelength is used for the data path between adjacent node devices, the same wavelength as that used in the data path is assigned to the control path, and the adjacent node When the same wavelength is not used between devices, the same wavelength as that used for the data path between the adjacent node devices is used for the control path. 3. A method for establishing a control path in a WDM ring network according to 1 or 2. Including a plurality of node devices connected by a ring-shaped optical transmission path through which a plurality of optical signals having different wavelengths are multiplexed and transmitted;
The node device inputs and outputs a wavelength-multiplexed optical signal transmitted to the optical transmission line, and separates, inserts, or passes the optical signal in units of wavelength, and performs separation, insertion, and passage. An OADM (Optical AddDrop Multiplexing) device in which the wavelength of the light is variable,
A relay device that is connected to a network outside the ring and the OADM, and performs packet relay processing;
A control path establishment method for a WDM (Wavelength Division Multiplexing) ring network, comprising:
In order for at least one node device among the plurality of node devices on the WDM ring to know the connection state of each of the plurality of node devices on the WDM ring, the plurality of nodes on the WDM ring are used with a predetermined wavelength. Requesting notification of address information to each of the node devices;
The one node device receives address information from a plurality of node devices on the WDM ring and grasps a connection status of the plurality of node devices on the WDM ring;
In the one node device that has received the data path setting request, in response to the control path change accompanying the data path setting, establishing a control path with other node devices on the WDM ring;
The one node device establishes a data path with the other node device;
Only including,
At least one node device that communicates with a control terminal among a plurality of node devices on the WDM ring is controlled from a wavelength for transferring user data used in each node device on the WDM ring when establishing a data path. When a path is determined and the same wavelength is used for the data path between adjacent node devices , the same wavelength as that used in the data path is assigned to the control path, and the adjacent node When the same wavelength is not used between devices, the same wavelength as that used for the data path between the adjacent node devices is used for the control path. 3. A method for establishing a control path in a WDM ring network according to 1 or 2.   The establishment of a control path in a WDM ring network according to claim 1 or 2, wherein if the same wavelength is not found between the node devices, a wavelength for transferring only control data is newly added. Method. Including a plurality of node devices connected by a ring-shaped optical transmission path through which a plurality of optical signals having different wavelengths are multiplexed and transmitted;
The node device inputs and outputs a wavelength-multiplexed optical signal transmitted to the optical transmission line, and separates, inserts, or passes the optical signal in units of wavelength, and performs separation, insertion, and passage. OADM ( optical AddDrop Multiplexing ) equipment,
A relay device that is connected to a network outside the ring and the OADM, and performs packet relay processing;
WDM ( Wavelength Division Multiplexing ) Ring network control path establishment method,
Using the wavelength of the data path as much as possible as the control path without dividing the wavelength of the control path and the data path between the node devices on the WDM ring;
A node device on a WDM ring dynamically changing the control path in response to the setting change of the data path;
At least one node device on the WDM ring that receives a data path setting request from the control terminal calculates an optimal control path between the node devices on the WDM ring;
The one node device notifies the other node devices on the WDM ring of the wavelength used as a control path and information of adjacent node devices;
When the one node device receives a path reception response from the other node device, it transmits a path setting request to the other node device, and new control paths of all the node devices on the WDM ring. Steps to complete the configuration of
When a new control path is established, in order to release the control path that was used before receiving the path setting request, the one node device makes another node device on the WDM ring Sending a path release request;
The other node device releases the wavelength of the control path used so far, and performs a release completion notification to the one node device;
A method for establishing a control path in a WDM ring network, comprising: Including a plurality of node devices connected by a ring-shaped optical transmission path through which a plurality of optical signals having different wavelengths are multiplexed and transmitted;
The node device inputs and outputs a wavelength-multiplexed optical signal transmitted to the optical transmission line, and separates, inserts, or passes the optical signal in units of wavelength, and performs separation, insertion, and passage. The wavelength of the OADM is variable ( Optical AddDrop Multiplexing ) Equipment,
A relay device that is connected to a network outside the ring and the OADM, and performs packet relay processing;
WDM ( Wavelength Division Multiplexing A ring network control path establishment method,
At least one node device among the plurality of node devices on the WDM ring uses a predetermined wavelength in order to know the connection state of each of the plurality of node devices on the WDM ring. Requesting notification of address information to each of a plurality of node devices on the WDM ring,
The one node device receives address information from a plurality of node devices on the WDM ring, and grasps connection states of the plurality of node devices on the WDM ring;
  In the one node device that has received the data path setting request, in response to the control path change accompanying the data path setting, establishing a control path with another node device on the WDM ring;
The one node device establishes a data path with the other node device;
At least one node device on the WDM ring that receives a data path setting request from the control terminal calculates an optimal control path between the node devices on the WDM ring;
The one node device notifies the other node devices on the WDM ring of the wavelength used as a control path and information of adjacent node devices;
When the one node device receives a path reception response from the other node device, it transmits a path setting request to the other node device, and new control paths of all the node devices on the WDM ring. Steps to complete the configuration of
When a new control path is established, in order to release the control path that was used before receiving the path setting request, the one node device makes another node device on the WDM ring Sending a path release request;
The other node device releases the wavelength of the control path used so far, and performs a release completion notification to the one node device;
A method for establishing a control path in a WDM ring network, comprising:   When transmitting the control data on the WDM ring, the node device searches the output ring search table from the destination address of the packet storing the control data, and configures the WDM ring as an output route 3. The method for establishing a control path in a WDM ring network according to claim 1, wherein either the outer ring or the inner ring is selected. The method for establishing a control path in a WDM ring network according to any one of claims 1 , 2, 4, and 5, wherein the relay device comprises an IP (Internet Protocol) router. The relay device, MPLS (Multi-Protocol Label Switching ) router, a layer 2 switch, ATM (Asynchronous Transfer Mode) switching system, consisting of any one of the frame relay switch, characterized in that, according to claim 1, 2 4. A method for establishing a control path in a WDM ring network according to any one of 4 and 5 . OADM ( Optical Optical) , which allows the wavelength of an optical signal to be separated, inserted, passed, separated, multiplexed, and passed in wavelength units to be variable AddDrop Multiplexing ) equipment,
A relay device that is connected to a network outside the ring and the OADM device and performs packet relay processing;
WDM ( Wavelength), which is formed by connecting multiple node devices with Division Multiplexing ) In ring network system,
The wavelength of the control path and the data path between the node devices on the WDM ring are not separated, the wavelength of the data path is used as much as possible as the control path, and the control path is dynamically changed according to the change of the data path. With means to change ,
At least one node device that communicates with the control terminal determines the control path from the wavelength for transferring user data used in each of the plurality of node devices on the WDM ring when establishing the data path, When the same wavelength is used for data paths between adjacent node devices, the same wavelength as that used in the data path is assigned to the control path, and the same wavelength is used between adjacent node devices. If not, a WDM ring comprising means for performing control to use the same wavelength as the data path used for the data path with the adjacent node device for the control path. Network system.   When the relay device of the node device sends control data onto the WDM ring, the output ring search table is searched from the destination address of the packet storing the control data, and the WDM ring is used as the output route. The WDM ring network system according to claim 9, further comprising means for selecting one of an outer ring and an inner ring constituting the WDM ring. At least one node device among a plurality of node devices on the WDM ring is
Means for requesting notification of address information to a plurality of node devices on the WDM ring using a predetermined wavelength in order to know the connection states of the plurality of node devices on the WDM ring;
Means for grasping connection statuses of a plurality of node devices on the WDM ring when address information is received from a plurality of node devices on the WDM ring;
Means for establishing a control path with another node device in response to a change of the control path accompanying the setting of the data path when receiving a data path setting request from a control terminal connected to the WDM ring When,
Means for establishing a data path with the other node device;
The WDM ring network system according to claim 9, comprising:   10. The WDM according to claim 9, further comprising means for controlling to newly add a wavelength for transferring only control data when the same wavelength is not found between the node devices. Ring network system. OADM ( Optical Optical) , which allows the wavelength of an optical signal to be separated, inserted, passed, separated, multiplexed, and passed in wavelength units to be variable AddDrop Multiplexing ) equipment,
A relay device that is connected to a network outside the ring and the OADM device and performs packet relay processing;
WDM ( Wavelength), which is formed by connecting multiple node devices with Division Multiplexing ) In ring network system,
The wavelength of the control path and the data path between the node devices on the WDM ring are not separated, the wavelength of the data path is used as much as possible as the control path, and the control path is dynamically changed according to the change of the data path. With means to change ,
At least one node device connected to the control terminal connected to the WDM ring is:
Means for calculating an optimal control path between node devices on a WDM ring when a data path setting request is received from the control terminal;
Means for notifying other node devices on the WDM ring of the wavelength used as a control path and information of adjacent node devices;
Means for transmitting a path setting request to the other node device when a path reception response is received from the other node device, and completing setting of a new control path of the node device on the WDM ring;
Means for transmitting a path release request to the other node device in order to release the control path used before receiving the path setting request when a new control path is established;
With
The said other node apparatus is equipped with the means to open | release the wavelength of the control path used so far, and to perform opening completion notification with respect to said one node apparatus, The said node apparatus is characterized by the above-mentioned. WDM ring network system. The WDM ring network system according to claim 9 or 13 , wherein the relay device is an IP (Internet Protocol) router. 14. The relay apparatus according to claim 9 or 13 , wherein the relay apparatus comprises any one of an MPLS (Multi-Protocol Label Switching) router, a layer 2 switch, an ATM (Asynchronous Transfer Mode) switch, and a frame relay switch. WDM ring network system. A node device of a WDM (Wavelength Division Multiplexing) ring network in which a plurality of optical signals having different wavelengths are multiplexed and transmitted between a plurality of node devices connected by an optical transmission line arranged in a ring shape,
Wavelength multiplexed optical signals transmitted to the optical transmission line are input and output, and the optical signals are separated, inserted, or passed in wavelength units, and the wavelength of the optical signal that is separated, inserted, and passed is variable. OADM (Optical AddDrop Multiplexing) device,
A relay device that is connected to a network outside the ring and the OADM device and performs packet relay processing;
Have
Without dividing the wavelength of the control path and the data path, as a control path, using the data path wavelength as much as possible, comprising means for dynamically changing the control path according to the change of the data path ,
When establishing a data path, the node device determines a control path from a wavelength for transferring user data used by each of a plurality of node devices on a WDM ring, and at that time, for the data path between adjacent node devices. If the same wavelength is used for the control path, the same wavelength as the wavelength used in the data path is assigned to the control path. A node device characterized by comprising means for performing control to use the same wavelength as a data path for a data path with a node device. When the relay device of the node device sends control data onto the WDM ring, the output ring search table is searched from the destination address of the packet storing the control data, and the WDM ring is used as the output route. 17. The node device according to claim 16 , further comprising means for selecting one of an outer ring and an inner ring that constitutes the ring. Means for requesting notification of address information to each of the node devices on the WDM ring using a predetermined wavelength in order to know the connection state of a plurality of node devices on the WDM ring;
Means for grasping connection statuses of a plurality of node devices on the WDM ring when address information is received from a plurality of node devices on the WDM ring;
In response to a data path setting request from a control terminal connected to the WDM ring, a control path is established with another node device on the WDM ring in response to the control path change accompanying the data path setting. Means to
Means for establishing a data path with the other node device;
The node device according to claim 16, further comprising: 17. The node device according to claim 16 , further comprising means for newly adding a wavelength for transferring only control data when the same wavelength is not found between the node devices. WDM ( wavelength) in which a plurality of optical signals with different wavelengths are multiplexed and transmitted between a plurality of node devices connected by an optical transmission line arranged in a ring shape Division Multiplexing) Ringune' network node device,
Wavelength multiplexed optical signals transmitted to the optical transmission line are input and output, and the optical signals are separated, inserted, or passed in wavelength units, and the wavelength of the optical signal that is separated, inserted, and passed is variable. OADM ( Optical AddDrop Multiplexing ) equipment,
A relay device that is connected to a network outside the ring and the OADM device and performs packet relay processing;
Have
A WDM that uses the wavelength of the data path as much as possible as a control path without dividing the wavelengths of the control path and the data path, and dynamically changes the control path according to the change of the data path, Means for requesting notification of address information to each of the node devices on the WDM ring using a predetermined wavelength in order to know the connection states of a plurality of node devices on the ring;
Means for grasping connection statuses of a plurality of node devices on the WDM ring when address information is received from a plurality of node devices on the WDM ring;
In response to a data path setting request from a control terminal connected to the WDM ring, a control path is established with another node device on the WDM ring in response to the control path change accompanying the data path setting. Means to
Means for establishing a data path with the other node device;
With
Means for calculating an optimum control path between node devices on a WDM ring when the node device receives a data path setting request from a control terminal connected to the node device;
Means for notifying other node devices on the WDM ring of the wavelength used as a control path and information of adjacent node devices;
Means for transmitting a path setting request to the other node device when a path reception response is received from the other node device, and completing setting of a new control path of the node device on the WDM ring;
Means for transmitting a path release request to the other node device in order to release the control path used before receiving the path setting request when a new control path is established;
A node device comprising: 21. The node apparatus according to claim 16 , wherein the relay apparatus is an IP (Internet Protocol) router. 21. The relay apparatus according to claim 16 or 20 , wherein the relay apparatus includes any one of an MPLS (Multi-Protocol Label Switching) router, a layer 2 switch, an ATM (Asynchronous Transfer Mode) switch, and a frame relay switch. The described node equipment.

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