WO2011018926A1

WO2011018926A1 - Network administration device and method for setting wavelength paths

Info

Publication number: WO2011018926A1
Application number: PCT/JP2010/061501
Authority: WO
Inventors: 到西岡; 有造松本
Original assignee: 日本電気株式会社
Priority date: 2009-08-12
Filing date: 2010-07-07
Publication date: 2011-02-17

Abstract

Provided is a network administration device that solves the problem that, when there are a large number of routes, an enormous amount of information is needed in order to set wavelength paths flexibly to accommodate optical switch configurations. A configuration management unit (302) acquires network configuration information, which indicates the connection relationships between wavelength switching devices (100), and intra-device configuration information, which indicates the connection relationships between routes and optical switches in the wavelength switching devices (100). A configuration conversion unit (303) converts the intra-device configuration information acquired by the configuration management unit (302) into switchable-route information, which indicates which routes each route can be connected to. A path control unit (304) calculates wavelength paths using the network configuration information acquired by the configuration management unit (302) and the switchable-route information from the configuration conversion unit (303). A setting unit (305) uses the wavelength switching devices (100) to set the wavelength paths calculated by the path control unit (304).

Description

Network management apparatus and wavelength path setting method

The present invention relates to a network management apparatus and a wavelength path setting method for setting a wavelength path of a wavelength network, and more particularly to a wavelength division multiplexing (WDM) network that transmits an optical signal in which a plurality of wavelength signals are multiplexed. The present invention relates to a network management apparatus and a wavelength path setting method for setting a wavelength path.

Wavelength networks that can transmit optical signals without converting optical signals into electrical signals are attracting attention. In the wavelength network, a wavelength path that connects client devices that are the start and end nodes of an optical signal is set. The wavelength path is defined by the path through which the optical signal is actually transmitted and the wavelength of the optical signal transmitted through the path.

In the conventional wavelength network, a ring network in which a relatively small number of relay nodes are provided on a ring-shaped route is used. In the ring network, the wavelength path is set in advance to either a clockwise route of the ring-shaped route or a counterclockwise route of the ring-shaped route.

Therefore, in a ring network, when a failure such as congestion occurs at a certain location, an optical signal cannot be transmitted avoiding the occurrence location, which may affect the entire wavelength network. For this reason, the ring network has a problem of low fault tolerance.

In recent years, a technique capable of variably setting a wavelength path has been proposed in order to improve fault tolerance. In such a technique, a wavelength path switching device capable of switching an optical signal output path for each wavelength is used as a relay node. As the wavelength network, a multi-ring network in which a plurality of ring networks are connected to each other, a mesh network in which wavelength path switching devices are arranged at each intersection of a mesh-like route, or the like is used.

A technique capable of variably setting the above wavelength path is described in Patent Document 1, for example.

In the optical network described in Patent Document 1, an optical cross-connect device is used as a wavelength path switching device. The optical cross-connect device includes an optical switch capable of arbitrarily switching an optical signal output path. Each optical cross-connect device detects the usage status of each of a plurality of routes connected to the own device, and notifies the detection result to the other optical cross-connect devices. Each optical cross-connect device switches the output path of the optical signal according to the detection result notified by the other optical cross-connect device, so that the wavelength path is set.

As a result, the wavelength path can be set while avoiding the congested portion on the wavelength network, so that the fault tolerance can be improved.

However, in order to enable the wavelength path switching device to arbitrarily switch the optical signal output path as in the optical cross-connect device in Patent Document 1, a large-scale optical switch is required. There has been a problem that the cost of the apparatus becomes high.

For this reason, in a general wavelength path switching device, the cost of the wavelength path switching device is reduced by limiting the scale of the optical switch. In this case, a route restriction occurs in a route that can be selected as an output route according to the configuration of the optical switch, and a wavelength constraint occurs in a wavelength that can be used in each route according to the configuration of the optical switch.
Therefore, when there is a wavelength path switching device using a small-scale optical switch, in order to set the wavelength path, it is necessary to consider the route restrictions and the wavelength restrictions.

As a technology capable of setting a wavelength path in consideration of the above-mentioned route restrictions and wavelength restrictions, there are a communication system described in Patent Document 2 and a WSON (Wavelength Switched Optical Network) described in Non-Patent Document 1. .

In the communication system described in Patent Document 2, a multi-ring network is used as a wavelength network. Also, an IP router is used as the client device, and a ROADM (Reconfigurable Optical Add / Drop Multiplexer) device is used as the wavelength path switching device.

The ROADM device has a route connected to itself as a user-network interface (UNI) that is a route between the IP router and the ROADM device, and a network-network interface that is a route between the ROADM device and another ROADM. ) And manage them in groups. Note that UNI and NNI are connected to each other on a one-to-one basis.

Each ROADM device notifies other ROADM devices of link information indicating the connection relation of the route in its own device. Each ROADM device sets the wavelength path by switching the output route of the optical signal based on the link information notified from the other ROADM device.

At this time, when the input route of the ROADM device is NNI, each ROADM device can select either the clockwise route or the counter-statistic route as the wavelength path of the ring network in the multi-ring network. .

However, in each ROADM device, UNI and NNI are connected to each other on a one-to-one basis. Therefore, when the input route is UNI, the routes that can be selected as the output route are the clockwise route and the counterclockwise route. It will be determined by either That is, the ROADM device has a route restriction.

In this case, each ROADM device adds information identifying whether the route that can be selected as the output route is a clockwise route or a counterclockwise route to the link information. Notify. Thereby, it becomes possible to set a wavelength path in consideration of a route restriction.

Further, in the WSON described in Non-Patent Document 1, each wavelength path switching device uses link connection information called Connectivity / Matrix / sub-TLV, which shows the relationship of each set in detail for each combination of routes, to the control device. Notice. Each wavelength path switching device notifies the control device of wavelength information called Wavelength / Set / Sub-TLV indicating wavelengths that can be transmitted in each path. Further, the topology information indicating the connection relationship of the wavelength path switching device is input to the control device.

The control device obtains the route constraint and the wavelength constraint of each wavelength path switching device based on the link connection information and the wavelength information. Then, the control device calculates a wavelength path that satisfies the obtained route constraint and wavelength constraint based on the input topology information, and sets the wavelength path. Thereby, the wavelength path can be set in consideration of the route restriction and the wavelength restriction.

JP 2003-209863 A JP 2008-98924 A

In the communication system described in Patent Document 2, the wavelength path route is limited to two, a clockwise route and a counterclockwise route of a ring-like route, and UNI and NNI are connected to each other on a one-to-one basis. It must be.

Therefore, regardless of the configuration of the optical switch in the wavelength path switching device, when the input route is UNI, the route that can be selected as the output route is the clockwise route and the counterclockwise route. It is determined by one of the routes. For this reason, the path restrictions are the same regardless of the configuration of the optical switch in the wavelength path switching device, so the wavelength path cannot be flexibly set according to the configuration of the optical switch. There's a problem.

Further, in the WSON described in Non-Patent Document 1, each wavelength path switching device is notified of link connection information indicating the relationship of the combination in detail for each combination of routes, and the route is determined based on the link connection information. Constraints are required. When the number of routes is large, the number of combinations of routes is very large compared to the number of routes, so there is a problem that the amount of information of link connection information becomes enormous.

Therefore, the techniques described in Patent Document 2 and Non-Patent Document 1 have a problem that when the number of paths is large, the amount of information for flexibly setting the wavelength path according to the configuration of the optical switch is enormous.

In the communication system described in Patent Document 2, the path restriction is taken into consideration, but the wavelength restriction is not taken into account, so that there is a problem that an incorrect wavelength path may be set.

In addition, since the WSON described in Non-Patent Document 1 does not have a mechanism for automatically detecting topology information, the topology information must be input manually. For this reason, there is a problem in that incorrect topology information is input, and as a result, an incorrect wavelength path may be set.

An object of the present invention is a network management apparatus that solves the problem that the amount of information for flexibly setting a wavelength path according to the configuration of an optical switch is large when the number of routes is large, It is to provide a wavelength path setting method.

In the network management device according to the present invention, a plurality of wavelength path switching devices capable of switching connections between optical signal paths for each wavelength of the optical signal using an optical switch are connected via a plurality of routes. A network management device for setting the wavelength path of a wavelength network, showing network configuration information indicating the connection relationship between each wavelength path switching device, and the connection relationship between the optical switch and each path of each wavelength path switching device. The acquisition means for acquiring the in-device configuration information, and the configuration for converting the in-device configuration information acquired by the acquisition means into switchable route information indicating a route connectable to the route for each route Using the conversion means, the network configuration information acquired by the acquisition means, and the switchable route information converted by the configuration conversion means, the control means for calculating the wavelength path, and the control The calculated wavelength path by means comprises a setting means for setting with each wavelength path switching apparatus.

Further, the wavelength path setting method according to the present invention includes a plurality of wavelength path switching devices capable of switching connections between optical signal paths for each wavelength of the optical signal using an optical switch via the plurality of paths. A wavelength path setting method based on a wavelength path setting method for setting a wavelength path of a connected wavelength network, the network configuration information indicating a connection relationship between each wavelength path switching device, and an optical switch of each wavelength path switching device An acquisition step of acquiring the in-device configuration information indicating the configuration of the device, and converting the acquired in-device configuration information into switchable route information indicating a route connectable to the route for each route A configuration conversion step, a control step of calculating the wavelength path using the acquired network configuration information and the converted switchable route information, and the calculated wavelength path Includes a setting step of setting with each wavelength path switching apparatus.

According to the present invention, even when the number of routes is large, it is possible to flexibly set the wavelength path according to the configuration of the optical switch with a relatively small amount of information.

It is the block diagram which showed the wavelength network of the 1st Embodiment of this invention. It is the block diagram which showed an example of the structure of a wavelength path switching apparatus. It is the block diagram which showed an example of the structure of the wavelength switch part. It is the block diagram which showed an example of the structure of a demultiplexing switching part. It is the block diagram which showed the other example of the structure of the demultiplexing switching part. It is the block diagram which showed an example of the structure of a wavelength network operation apparatus. It is explanatory drawing which showed an example of network configuration information. It is the flowchart which showed an example of operation | movement of a wavelength network. It is the flowchart which showed the other example of operation | movement of a wavelength network.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, components having the same function may be denoted by the same reference numerals and description thereof may be omitted.

(First embodiment)
FIG. 1 is a block diagram showing a wavelength network according to a first embodiment of the present invention. In FIG. 1, the wavelength network includes a wavelength switching device 100, a packet switching device 200, and a wavelength network (NW: Network) operation device 300. In this embodiment, the wavelength network is a multi-ring network in which a plurality of ring networks having ring-shaped paths are connected to each other. However, the wavelength network is not limited to the multi-ring network and can be changed as appropriate. is there.

There are a plurality of wavelength switching devices 100 and packet switching devices 200, and these wavelength switching devices 100 and packet switching devices 200 are connected via a plurality of paths. In FIG. 1, eight wavelength switching devices 100 (100-1 to 100-8) and eight packet switching devices 200 are shown.

The wavelength switching device 100 is sometimes called a wavelength path switching device. Each of the wavelength switching devices 100 has a plurality of paths that are routes connected to the own wavelength switching device. In the route, there are a WDM line (Wavelength Division Multiplexing Line) that connects the wavelength switching devices 100 and a client line (Client Line) that connects the wavelength switching device 100 and the packet switching device 200. is there.

The WDM line is also called an NNI interface and transmits a wavelength multiplexed signal obtained by multiplexing a plurality of wavelength signals as an optical signal. In FIG. 1, four WDM lines are connected to three wavelength switching devices 100-1, 100-4, and 100-8 of the eight wavelength switching devices 100, and other wavelength switching devices. Two WDM lines are connected to 100.

The client line is also called a UNI interface and can transmit a wavelength signal as an optical signal. Note that there may be a plurality of client lines connected to each wavelength switching device 100.

The wavelength switching device 100 is a relay node that relays optical signals on the wavelength network. More specifically, when receiving an optical signal from a certain input route, the wavelength switching device 100 outputs the optical signal to an output route different from the input route.

The packet switching device 200 is a client device that can be a start point node and an end point node of a wavelength path, and is also a relay node of the packet network 400. The packet switching device 200 can switch a packet route that is a route for a packet signal in the packet network 400.

The wavelength network operation device 300 is sometimes called a network management device. The wavelength network operation device 300 sets the wavelength path of the wavelength network using the wavelength switching device 100. A wavelength path is defined by a path through which an optical signal is actually transmitted and a wavelength of the optical signal on the path.

Hereinafter, each device will be described in detail.

FIG. 2 is a block diagram showing an example of the configuration of the wavelength switching device 100. A plurality of WDM lines 111 (more specifically, WDM lines 111-1 to 111-4) and a plurality of client lines 112 are connected to the wavelength switching device 100 shown in FIG.

In FIG. 2, the wavelength switching device 100 includes a wavelength switching unit 101 that transmits / receives an optical signal transmitted through the WDM line 111, an optical transmitter / receiver 102 that transmits / receives an optical signal transmitted through the client line 112, and a WDM line 111. A demultiplexing / switching unit 103 that converts an optical signal to be transmitted and an optical signal transmitted through the client line 112, an internal interface 104 that is a path interposed between the wavelength switching unit 101 and the demultiplexing / switching unit 103, and each unit And an apparatus control unit 105 for controlling. The internal interface 104 is divided into first to fourth route groups having a plurality of routes.

The wavelength switching unit 101 is connected with a route in the WDM line 111 and the internal interface 104 as a route for an optical signal. When the wavelength switching unit 101 receives an optical signal from an input route out of these routes, the wavelength switching unit 101 transmits the optical signal to an output route different from the input route.

Here, the wavelength switching unit 101 uses a wavelength selective switch called WSS (Wavelength Selected Switch). The wavelength selective switch can switch the output path of the optical signal for each wavelength while suppressing deterioration in the quality of the optical signal.

However, since the wavelength selective switch is a 1: N type (1-input multiple-output type) optical switch, the degree of freedom in switching the connection between routes is low. For this reason, the wavelength selective switch cannot select any route as the output route. In the wavelength selective switch, a route that can be selected as an output route is determined according to the input route. The paths that can be connected to each other by the wavelength selective switch are the path restrictions of the wavelength switching device.

FIG. 3 is a block diagram showing an example of the configuration of the wavelength switching unit 101. In FIG. 3, the wavelength switching unit 101 includes wavelength selective switches 121A, 121B, 122A, 122B, 123A, 123B, 124A, and 124B.

The wavelength selective switch 121A has a duplexer 121A. The wavelength selective switch 121A is connected to the WDM line 111-1. Upon receiving the wavelength multiplexed signal from the WDM line 111-1, the wavelength selective switch 121A demultiplexes the wavelength multiplexed signal into a single wavelength wavelength signal using the demultiplexer 121A, and each of the demultiplexed wavelength signals. Is transmitted to either the wavelength selective switch 123B or the route in the first route group.

The wavelength selective switch 121B has a multiplexer 121B1. The wavelength selective switch 121A is connected to the WDM line 111-1. When the wavelength selective switch 121B receives the wavelength signal from the wavelength selective switch 123A and the first path group, the wavelength selective switch 121B combines the wavelength signal using the multiplexer 121B and transmits it to the WDM line 111-1 as a wavelength multiplexed signal.

Also, the wavelength selective switch 122A has a duplexer 122A. The wavelength selective switch 121A is connected to the WDM line 111-2. When receiving the wavelength multiplexed signal from the WDM line 111-2, the wavelength selective switch 122A demultiplexes the wavelength multiplexed signal into a single wavelength wavelength signal using the demultiplexer 122A, and each of the demultiplexed wavelength signals. Is transmitted to either the wavelength selective switch 124B or the route in the second route group.

The wavelength selective switch 122B has a multiplexer 122B1. The wavelength selective switch 121A is connected to the WDM line 111-2. When the wavelength selective switch 122B receives the wavelength signal from the wavelength selective switch 124A and the second path group, the wavelength selective switch 122B multiplexes the wavelength signal using the multiplexer 122B and transmits it to the WDM line 111-2 as a wavelength multiplexed signal.

Also, the wavelength selective switch 123A has a duplexer 123A. The wavelength selective switch 121A is connected to the WDM line 111-3. When receiving the wavelength multiplexed signal from the WDM line 111-3, the wavelength selective switch 123A demultiplexes the wavelength multiplexed signal into a single wavelength wavelength signal using the demultiplexer 123A, and each of the demultiplexed wavelength signals. Is transmitted to either the wavelength selective switch 121B or the route in the third route group.

The wavelength selective switch 123B has a multiplexer 123B1. The wavelength selective switch 121A is connected to the WDM line 111-3. When the wavelength selective switch 123B receives the wavelength signal from the wavelength selective switch 121A and the third path group, the wavelength selective switch 123B combines the wavelength signal using the multiplexer 123B and transmits it to the WDM line 111-3 as a wavelength multiplexed signal.

Also, the wavelength selective switch 124A has a duplexer 124A. The wavelength selective switch 121A is connected to the WDM line 111-4. When receiving the wavelength multiplexed signal from the WDM line 111-4, the wavelength selective switch 124A demultiplexes the wavelength multiplexed signal into a single wavelength wavelength signal using the demultiplexer 124A, and each of the demultiplexed wavelength signals. Is transmitted to either the wavelength selective switch 122B or the route in the fourth route group.

The wavelength selective switch 124B has a multiplexer 124B1. The wavelength selective switch 121A is connected to the WDM line 111-4. When the wavelength selective switch 124B receives the wavelength signal from the wavelength selective switch 122A and the fourth path group, the wavelength selective switch 124B multiplexes the wavelength signal using the multiplexer 124B and transmits it to the WDM line 111-4 as a wavelength multiplexed signal.

In the case of the wavelength switching unit 101 shown in FIG. 3, for example, in the wavelength selective switch 121A, the WDM lines 111-1 and 111-3 can be connected to the WDM line 111-1 and the route in the first route group. It becomes a way.

Return to Figure 2. The optical transmission / reception unit 102 is an input / output port of the client line 112. There are a plurality of optical transmission / reception units 102, each of which is connected to one of the client lines 112 on a one-to-one basis. The optical transmission / reception unit 102 receives a wavelength signal of a single wavelength from the client line 112 connected to itself as an optical signal, and transmits the optical signal to the demultiplexing / switching unit 103.

A client line 112 and an internal interface 104 are connected to the demultiplexing switching unit 103 as optical signal paths. The demultiplexing switching unit 103 is connected to the client line 112 via the optical transmission / reception unit 102. When the demultiplexing switching unit 103 receives an optical signal from an input route out of those routes, the demultiplexing switching unit 103 transmits the optical signal to an output route different from the input route.

Here, the demultiplexing switching unit 103 uses an optical filter such as an AWG (Arrayed Waveguide Grating) and an optical switch called OXC (Optical Cross-Connect). The OXC is an N: N type (multiple input multiple output) optical switch. The OXC may be a space coupling type optical switch or a waveguide type optical switch.

4A and 4B are block diagrams illustrating an example of the configuration of the demultiplexing switching unit 103. FIG. 4A shows a configuration using only one large-scale OXC, and FIG. 4B shows a configuration using a plurality of small-scale OXCs.

4A, the demultiplexing switching unit 103 includes a plurality of optical filters 131 and one OXC 132.

The optical filter 131 has a first input / output port and a plurality of second input / output ports. The first input / output port is connected to one of the paths in the internal interface 104 on a one-to-one basis. Each of the second input / output ports is connected to the OXC 132.

When the optical filter 131 receives an optical signal from a route in the internal interface 104, the optical filter 131 transmits the optical signal to the OXC 132 from the second input / output port corresponding to the wavelength of the optical signal. Further, when the optical filter 131 receives an optical signal from the OXC 132, the optical filter 131 transmits the optical signal from the first input / output port to the wavelength switching unit 101 via a route in the internal interface 104.

When the OXC 132 receives the optical signal from the optical transmission / reception unit 102, the OXC 132 transmits the optical signal to the second input / output port of the optical filter 131 corresponding to the wavelength of the optical signal. Further, when the OXC 132 receives an optical signal from the optical filter 131, the OXC 132 transmits the optical signal to the optical transmission / reception unit 102 corresponding to the wavelength of the optical signal.

4B, the demultiplexing switching unit 103 includes a plurality of optical filters 133 and OXCs 134 and 135. Note that the number of OXCs is only two in FIG. 4B, but may actually be two or more.

The optical filter 133 has a first input / output port and a plurality of second input / output ports. The first input / output port is connected to one of the paths in the internal interface 104 on a one-to-one basis. Each of the second input / output ports is connected to the

OXC

134 or 135.

When the optical filter 133 receives an optical signal from a route in the internal interface 104, the optical filter 133 transmits the optical signal to the

OXC

134 or 135 from the second input / output port corresponding to the wavelength of the optical signal. Further, when the optical filter 133 receives an optical signal from the

OXC

134 or 135, the optical filter 133 transmits the optical signal from the first input / output port to the wavelength switching unit 101 via a route in the internal interface 104.

OXCs

134 and 135, when receiving an optical signal from optical transceiver 102, transmit the optical signal to the second input / output port of optical filter 133 corresponding to the wavelength of the optical signal. Further, when receiving the optical signal from the optical filter 133, the

OXCs

134 and 135 transmit the optical signal to the optical transmission / reception unit 102 corresponding to the wavelength of the optical signal.

By using the demultiplexing / switching unit 103 as shown in FIG. 4A or 4B, the path restriction based on the wavelength selective switch of the wavelength switching unit 101 can be solved to some extent. For example, if there is no demultiplexing / switching unit 103 and each path in the internal interface 104 is directly connected to one of the optical transmission / reception units 102, the client line that can be connected to the WDM line of the wavelength selective switch is Only the client line of the optical transmitter / receiver 102 connected to the wavelength selective switch via the internal interface 104 is provided.

If there is the demultiplexing switching unit 103 as shown in FIG. 4A or 4B, the connection between the path in the internal interface 104 and the optical transmission / reception unit 102 can be switched by OXC. The number of client lines that can be connected increases, and route restrictions are eliminated.

4A, the OXC 132 is connected to all the second input / output ports of the optical filter 131 and all the optical transceivers 102. Therefore, the output route of the optical transmission / reception unit 102 is switched to an arbitrary route in the internal interface 104 by switching the output route in the OXC 132, and the optical signal from the internal interface 104 is switched. Can be switched to any optical transceiver 102.

Therefore, all the route restrictions between the WDM line 111 and the client line 112 can be eliminated. The route restriction between the WDM lines 111 cannot be solved.

On the other hand, a small-scale optical switch is used in the demultiplexing / switching unit 103 shown in FIG. 4B. That is, each of the

OXCs

134 and 135 is connected to a part of the second input / output ports of the optical filter 131 and a part of the optical transceiver 102. For this reason, even if the output route is switched by the

OXCs

134 and 135, the output route of the optical signal from the optical transceiver 102 is switched to an arbitrary route in the internal interface 104, and from the internal interface 104 The output path of the optical signal cannot be switched to any optical transmission / reception unit 102.

For this reason, some route restrictions between the WDM line 111 and the client line 112 remain.

Therefore, the path restriction of the wavelength switching device 100 differs depending on the configuration of the optical switch (wavelength selection switch and OXC) in the wavelength switching device 100.

Further, the wavelengths of optical signals that can be input / output at the second input / output ports of the

optical filters

131 and 133 are determined in advance. The wavelength of the optical signal that can be input / output at the second input / output port is the wavelength of the optical signal that can be used for the wavelength path.

In the demultiplexing / switching unit 103 shown in FIG. 4A, the OXC 132 is connected to all the second input / output ports and all the optical transceivers 102 of each optical filter 131, so all the client lines and all the WDMs are connected. The line can use any wavelength within the wavelengths available for the wavelength path.

On the other hand, in the demultiplexing / switching unit 103 shown in FIG. 4B, the

OXCs

134 and 135 are connected to a part of the second input / output ports of each of the optical filters 131 and a part of the optical transmission / reception part 102. In addition, the wavelength of the optical signal that can be transmitted through the WDM line is limited. This restriction becomes the wavelength restriction of the wavelength switching device 100.

For example, only the wavelengths λ1 to λ3 can be used in the client line connected to the OXC 134 via the optical transmission / reception unit 102, and the wavelengths λ4 and λ5 can be used in the client line connected to the OXC 135 via the optical transmission / reception unit 102. Can only be used.

As described above, the path restriction and the wavelength restriction in the wavelength switching device 100 differ depending on the internal configuration of the wavelength switching device 100, specifically, the configuration of the optical switch (wavelength selection switch and OXC).

Return to Figure 2. The device control unit 105 includes device identification information that identifies the own device (wavelength switching device 100), route information that includes a plurality of route identification information that identifies each of a plurality of routes of the optical signal in the device, In-device configuration information indicating the configuration of the optical switch of the device is held.

More specifically, the in-device configuration information includes the connection relationship with the path of the optical switch, more specifically, the path configuration information indicating the path that can be connected to each other in the optical switch for each optical switch, And vacant wavelength information indicating the wavelength of an optical signal that can be transmitted in each path in the apparatus. Therefore, the in-device configuration information indicates the connection relationship between the optical switch and each path of each wavelength switching device 100 and the wavelength of the optical signal that can be transmitted in each path.

The path configuration information includes, for example, information indicating a path (a path in the WDM line 111 and the internal interface 104) that can be connected by the wavelength selective switch for each wavelength selective switch in the wavelength switching unit 101; For each OXC in the demultiplexing switching unit 103, information indicating a path (internal interface 104 and client line 112) connectable by the OXC is included.

Also, the device control unit 105 can switch the output path of the optical signal for each wavelength by switching the optical switch in the wavelength switching unit 101 and the demultiplexing switching unit 103.

Next, the configuration of the wavelength network operation apparatus 300 will be described.

FIG. 5 is a block diagram showing an example of the configuration of the wavelength network operation apparatus 300. In FIG. 5, the wavelength network operation apparatus 300 includes a user I / F (interface) 301, a configuration management unit 302, a configuration conversion unit 303, a path control unit 304, and a setting unit. 305. Further, the wavelength network operation device 300 can be connected to the remote terminal 500 wirelessly or by wire. The remote terminal 500 accepts various information from the wavelength network operator and inputs the accepted information to the user I / F 301.

User I / F 301 may be referred to as accepting means. The user I / F 301 receives a setting request for setting a wavelength path from the wavelength network operator via the remote terminal 500.

In the present embodiment, the setting request includes determination information for determining a client line used for the wavelength path. The client lines used for the wavelength path are the first client line that is the input path of the optical signal in the first wavelength switching device 100 in the wavelength path and the output path of the optical signal in the last wavelength switching device 100 in the wavelength path. Is the last client line.

The discrimination information includes, for example, first device identification information that identifies the first wavelength switching device 100, second device identification information that identifies the last wavelength switching device 100, and the optical transceiver 102 of the first wavelength switching device 100. The first port number to be identified and the second port number to identify the optical transceiver 102 of the last wavelength switching device 100 are included.

The configuration management unit 302 may be called an example of a management unit. The configuration management unit 302 acquires network configuration information indicating a connection relationship (wavelength network topology) between the wavelength switching devices 100 and in-device configuration information of each wavelength path switching device.

More specifically, the configuration management unit 302 includes a configuration discovery unit 311, an NW configuration information storage unit 312, and an in-device information storage unit 313, and each unit performs the following processing.

The configuration discovery unit 311 acquires device identification information, route information, and in-device configuration information from each of the wavelength switching devices 100. The configuration discovery unit 311 may acquire these pieces of information periodically or when the user I / F 301 receives a setting request.

The configuration discovery unit 311 associates the device identification information and the route information acquired from each wavelength switching device 100 to generate network configuration information.

In the network configuration information, if the same path identification information is included in the route information associated with different apparatus identification information, the wavelength switching device 100 specified by the apparatus identification information is included in the path identification information. It indicates that they are connected to each other through a specified path. Therefore, the configuration discovery unit 311 acquires network configuration information indicating the connection relationship of the wavelength switching device 100.

The configuration discovery unit 311 stores the acquired network configuration information in the NW configuration information storage unit 312.

Further, the configuration discovery unit 311 stores the device identification information acquired from each wavelength switching device 100 and the in-device configuration information in the in-device information storage unit 313 in association with each other.

The configuration conversion unit 303 converts the path configuration information included in the in-device configuration information stored in the in-device information storage unit 313 into a path that can be connected to the path for each path of each wavelength switching device 100. Convert to the indicated switchable route information. More specifically, the switchable route information is information indicating a route connectable to the route for each route identification information for specifying the route.

The configuration conversion unit 303 adds the converted switchable route information and the free wavelength information included in the in-device configuration information to the network configuration information in the NW configuration information storage unit 312.

FIG. 6 is an explanatory diagram showing an example of network configuration information in certain device identification information. FIG. 6 shows network configuration information 600 for each of the WDM lines 111-1 to 111-4 and the client lines 112-1 to 112-4.

Each network configuration information 600 includes route identification information 601, switchable route information 602, and free wavelength information 603.

The route identification information 601 is information unique to each route, and identifies each route. The path identification information 601 is represented by a bit string in which each bit indicates a different path, the bit indicating the specified path is “1”, and the other bits are “0”.

The switchable route information 602 indicates a route that can be connected to the route specified by the route identification information 601. The switchable route information 602 is represented by a bit string similar to the route identification information 601, the bit indicating a connectable route is “1”, and the other bits are “0”.

Vacant wavelength information 603 indicates a vacant wavelength that is a wavelength of an optical signal that can be transmitted in each path in the device itself. The free wavelength information 603 is represented by a bit string in which each bit indicates a different wavelength, the bit indicating the free wavelength is “0”, and the other bits are “1”.

Return to FIG. The path control unit 304 calculates the wavelength path of the minimum cost (shortest path) using the discrimination information in the setting request received by the user I / F 301 and the network configuration information in the NW configuration information storage unit 312. Since the network configuration information includes switchable route information, topology information, and free wavelength information, the path control unit 304 is based on the discrimination information, switchable route information, topology information, and free wavelength information. Thus, the wavelength path is calculated.

Specifically, the route control unit 304 includes a constraint conversion unit 321 and a route calculation unit 322, and each unit performs the following processing.

Constraint conversion unit 321 is also referred to as exclusion means. The constraint conversion unit 321 specifies a route that is not connectable to each of the client lines of the wavelength path determined by the determination information as an excluded route to be excluded (excluded from the calculation of the wavelength path), and indicates the excluded route Generate initial route restriction information.

Also, the constraint conversion unit 321 generates initial wavelength constraint information indicating the free wavelength of the client line determined by the determination information based on the network configuration information.

For example, assume that the wavelength paths from the wavelength switching devices 100-1 to 100-8 in FIG. 1 are calculated, and the network configuration information of the wavelength switching device 100-8 has the configuration shown in FIG. Further, the client line 112-1 is assumed to be a wavelength path client line.

In this case, since the switchable route information 602 of the client line 112-1 is “00000001” indicating the WDM line 111-1, the constraint conversion unit 321 excludes each of the WDM lines 111-2 to 41-2. As specified. The constraint conversion unit 321 generates initial route constraint information indicating the WDM lines 111-2 to 114-2.

Similarly, the constraint conversion unit 321 generates initial route constraint information for the wavelength switching device 100-8.

Further, since the free wavelength information 603 of the client line 112-1 is “1111... 1110” indicating the wavelength λ1, the constraint conversion unit 321 generates initial wavelength constraint information indicating the wavelength λ1. More specifically, the constraint conversion unit 321 checks whether or not the wavelength λ1 can be used in the wavelength switching device 100-8, and if the wavelength λ1 is usable in the wavelength switching device 100-8, Initial wavelength constraint information indicating λ1 is generated. The empty wavelength information 603 represents the wavelengths λ1, λ2, λ3,... In order from the least significant bit.

The route calculation unit 322 is also called calculation means. The path calculation unit 322 calculates a wavelength path using a path calculation method called CSPF (Constraint based Shortest Path First).

Specifically, the route calculation unit 322 excludes the connection relationship of the wavelength switching devices connected via the exclusion route indicated by the route restriction information from the network configuration information stored in the NW configuration information storage unit 312. . For example, the route calculation unit 322 excludes (Excludes), from the network configuration information, route identification information that specifies a route that cannot be used as a wavelength path, which is the route restriction indicated by the route restriction information.

The route calculation unit 322 is based on the network configuration information excluding the connection relationship, the discrimination information in the setting request received by the user I / F 301, and the initial wavelength constraint information generated by the constraint conversion unit 321. The wavelength path of the minimum cost from the first route (client line) determined by the determination information to the last route (client line) is calculated. Here, as the wavelength path calculation algorithm, a Dijkstra algorithm capable of calculating the wavelength path in consideration of the wavelength constraint is used.

In this case, since the initial route restriction information indicates each of the WDM lines 111-2 to 11-4 as the excluded route, the route calculation unit 322 determines that only the WDM line 111-1 can be used, and the WDM line 111 −1 is selected as a wavelength path route candidate. In addition, since the initial wavelength constraint information indicates the wavelength λ1, the path calculation unit 322 selects the wavelength λ1 as a wavelength path wavelength candidate.

Subsequently, the path calculation unit 322 pays attention to the wavelength switching device 100-2 connected to the WDM line 111-1. The route calculation unit 322 selects a WDM line connectable to the WDM line 111-1 based on the switchable route information in the network configuration information. Based on the free wavelength information, the path calculation unit 322 selects a WDM line that can use the wavelength λ1 among the selected WDM lines as a wavelength path candidate.

The route calculation unit 322 repeats the above processing to calculate the wavelength path with the lowest cost from the first client line to the last client line.

The setting unit 305 sets the wavelength path calculated by the route control unit 304 using each wavelength switching device 100.

Next, the operation will be described.

First, the operation when acquiring wavelength network configuration information will be described.

First, the configuration discovery unit 311 transmits a configuration information transmission request to each device control unit 105 of the wavelength switching device 100 in the wavelength network. Upon receiving the transmission request, the device control unit 105 transmits the held device identification information, route information, and in-device configuration information to the configuration discovery unit 311 of the wavelength network operation device 300.

Subsequently, every time device identification information, route information, and in-device configuration information are received, the configuration discovery unit 311 associates the device identification information with the route information and stores them in the NW configuration information storage unit 312. . Furthermore, whenever the information is received, the configuration discovery unit 311 associates the device identification information with the in-device configuration information and stores them in the in-device information storage unit 313.

After that, the configuration discovery unit 311 transmits an operation command to the configuration conversion unit 303 when the storage of the route information and the in-device configuration information is completed for all the wavelength switching devices 100.

When receiving the operation command, the configuration conversion unit 303 acquires the in-device configuration information stored in the in-device information storage unit 313, and converts the in-device configuration information into route restriction information. The configuration conversion unit 303 adds the route restriction information to the network configuration information in the NW configuration information storage unit 312 and ends the operation.

Next, the operation when setting the wavelength path will be described. FIG. 7 is a flowchart for explaining this operation.

In step S701, the wavelength network operator inputs a setting request to the user I / F 301 using the remote terminal 500. When receiving the setting request, the user I / F 301 transmits the setting request to the route calculation unit 322. When the route calculation unit 322 receives the setting request, the route calculation unit 322 executes Step S702.

In step S702, the route calculation unit 322 determines the client line of the wavelength path based on the determination information in the setting request.

For example, the path calculation unit 322 searches the in-device information storage unit 313 for the first device identification information in the discrimination information, and from the in-device configuration information associated with the searched first device identification information. The route identification information associated with the 1-port identification information is further searched. The route calculation unit 322 can determine the client line specified by the searched route identification information, and similarly, the route calculation unit 322 can determine the last client line of the wavelength path.

When the path calculation unit 322 determines the client line of the wavelength path, the path calculation unit 322 transmits client line information including path identification information for specifying each of the client lines to the constraint conversion unit 321. When receiving the client line information, the constraint conversion unit 321 executes Step S703.

In step S703, the constraint conversion unit 321 acquires network configuration information from the NW configuration information storage unit 312 and generates initial route constraint information and initial wavelength constraint information based on the network configuration information and client line information. . The constraint conversion unit 321 transmits the network configuration information, initial route constraint information, and initial wavelength constraint information to the route calculation unit 322. When receiving the network configuration information, the initial route restriction information, and the initial wavelength restriction information, the route calculation unit 322 executes Step S704.

In step S704, the route calculation unit 322 excludes, from the network configuration information, route identification information that identifies a route that cannot be used as a wavelength path, which is the route constraint indicated by the initial route constraint information. The route calculation unit 322 calculates a wavelength path with the minimum cost from the first client line to the last client line determined by the determination information based on the network configuration information from which the route identification information is excluded. The route calculation unit 322 transmits path information indicating the calculated wavelength path to the setting unit 305. When receiving the path information, the setting unit 305 executes step S705.

In step S705, upon receiving the path information, the setting unit 305 sets the wavelength path indicated by the path information using the wavelength switching device 100, and ends the operation.

More specifically, the setting unit 305 generates a switching request including paths connected to each other in each wavelength switching device 100 based on the path information. The setting unit 305 sets the wavelength path by transmitting the switching request to each wavelength switching device 100.

In addition, when each device control unit 105 of the wavelength switching device 100 receives the switching request, the device control unit 105 switches the wavelength selection switch and the OXC so that the paths indicated by the switching request are connected to each other.

By operating as described above, it is possible to set a wavelength path with a minimum cost in a single layer (wavelength network layer) in consideration of route restrictions and wavelength restrictions.

According to the present embodiment, the configuration management unit 302 includes the network configuration information indicating the connection relationship between the wavelength switching devices 100, the optical switch of each wavelength switching device 100, and the connection relationship between the paths. Get configuration information. The configuration conversion unit 303 converts the in-device configuration information acquired by the configuration management unit 302 into switchable route information indicating a route connectable to the route for each route. The path control unit 304 calculates the wavelength path using the network configuration information acquired by the configuration management unit 302 and the switchable route information converted by the configuration conversion unit 303. The setting unit 305 sets the wavelength path calculated by the route control unit 304 using each wavelength switching device 100.

In this case, the in-device configuration information indicating the connection relationship between the optical switch and the route is converted into the switchable route information, and the wavelength path is calculated based on the route restriction information.

Therefore, the wavelength path can be flexibly set according to the configuration of the optical switch. Even if the number of routes increases, the increase in the number of optical switches is usually smaller than the increase in the number of combinations of routes, so the amount of information when the number of routes increases The increase amount can be reduced. Therefore, even when the number of routes is large, the wavelength path can be flexibly set according to the configuration of the optical switch with a relatively small amount of information.

In the present embodiment, the in-device configuration information further indicates the wavelength of the optical signal that can be transmitted in each path. In this case, the wavelength path can be set in consideration of the wavelength constraint, so that the wavelength path can be set more accurately.

In the present embodiment, the user I / F 301 accepts discrimination information for discriminating between the first client line of the wavelength path and the last client of the wavelength path. Based on the discrimination information and the switchable route information, the constraint conversion unit 321 is connected to the wavelength switching device 100 connected via the excluded route that is not connectable to the first client line and the last client line. Is excluded from the network configuration information. The route calculation unit 322 calculates the wavelength path using the network configuration information from which the excluded route is excluded by the constraint conversion unit 321 and the switchable route information.

In this case, the wavelength path is calculated using the network configuration information from which the excluded route that is not connectable to the first client line and the last client line is excluded. Therefore, since the wavelength path can be calculated using the network configuration information that already satisfies the route restriction between the client line and the WDM line, the wavelength path can be easily calculated.

(Second Embodiment)
In the present embodiment, a wavelength operation apparatus that sets a packet path and a wavelength path in association with each other in a multilayer network including a packet network and a wavelength network will be described.

The user I / F 301 accepts a setting request including packet identification information indicating the packet switching device 200 that is a start node and an end node of a packet path in the packet network 400.

The configuration discovery unit 311 acquires topology information indicating the connection relationship between the packet switching devices 200 and the connection relationship between the wavelength switching device 100 and the packet switching device 200 as network configuration information. As a result, the network configuration information further indicates the connection relationship between the packet switching device 200 and the connection relationship between the wavelength switching device 100 and the packet switching device 200.

For example, the configuration discovery unit 311 acquires packet identification information for specifying the packet switching device 200 and packet path identification information for specifying the route of the packet switching device 200 from each of the packet switching devices 200. Get topology information.

The route control unit 304 (more specifically, the route calculation unit 322) is based on the network configuration information stored in the configuration discovery unit 311 and the packet identification information included in the setting request received by the user I / F 301. Calculate the wavelength path and packet path.

The route control unit 304 sets the calculated wavelength path using the wavelength switching device 100 and sets the calculated packet path using the packet switching device 200.

Next, the operation will be described.

FIG. 8 is a flowchart for explaining an example of the operation of the wavelength network in the present embodiment.

In step S801, the wavelength network operator inputs a setting request to the user I / F 301 using the remote terminal 500. When receiving the setting request, the user I / F 301 transmits the setting request to the route calculation unit 322. When receiving the setting request, the route calculation unit 322 executes Step S802.

In step S802, the route calculation unit 322 extracts the discrimination information from the setting request and acquires the network configuration information from the NW configuration information storage unit 312. The route calculation unit 322 uses the route information and topology information in the network configuration information, and the discrimination information, and uses the end-to-end minimum cost route (hereinafter referred to as an E2E route) from the start node to the end node. ). At this time, the path calculation unit 322 calculates the E2E path without considering the path constraint and the wavelength constraint of the wavelength path. When calculating the end-to-end route, the route calculation unit 322 executes Step S803.

In step S803, the route calculation unit 322 checks whether or not a wavelength path is included in the E2E route by checking whether or not the WDM line in the calculated E2E route is included. . If the wavelength path is not included, the path calculation unit 322 executes Step S804, and if the wavelength path is included, the path calculation unit 322 executes Step S805.

In step S804, since the wavelength path is not included in the E2E route, the route calculation unit 322 transmits route information indicating the E2E route to the setting unit 305. Upon receiving the route information, the setting unit 305 sets the packet path on the E2E route indicated by the route information using the packet switching device 200, and ends the operation.

On the other hand, in step S805, the route calculation unit 322 determines the first route and the last route of the wavelength paths in the E2E route. The route calculation unit 322 recalculates the wavelength path from the first route to the last route.

In this embodiment, unlike the first embodiment, the route calculation unit 322 calculates a wavelength path without using the constraint conversion unit 321. That is, the route calculation unit 322 calculates the wavelength path without considering the initial route constraint information and the initial wavelength constraint information. This is because, unlike the first embodiment, the first client line and the last client line can be arbitrarily selected.

When calculating the wavelength path, the route calculation unit 322 executes step S806.

In step S806, the route calculation unit 322 transmits path information indicating the recalculated wavelength path to the setting unit 305. When receiving the path information, the setting unit 305 sets the wavelength path indicated by the path information using the wavelength switching device 100.

In addition, when the path calculation unit 322 transmits the path information, the path calculation unit 322 executes Step S807.

In step S807, the route calculation unit 322 registers the recalculated wavelength path as a virtual link, and then executes step S808.

Note that this registered virtual link is used in the calculation of the E2E route in step S801.

In step S808, the route calculation unit 322 removes the route for which the wavelength path is set from the E2E route, and executes step S809.

In step S809, the route calculation unit 322 transmits route information indicating the E2E route from which the route for which the wavelength path is set is excluded to the setting unit 305. Upon receiving the route information, the setting unit 305 sets the packet path on the E2E route indicated by the route information using the packet switching device 200, and ends the operation.

By operating as described above, it becomes possible to set the wavelength path and the packet path with the shortest cost in the multi-layer while considering the path restrictions and the wavelength restrictions of the wavelength path.

According to this embodiment, the network configuration information further indicates the connection relationship between the packet switching devices and the connection relationship between the packet switching devices and the wavelength path switching devices. In addition, the user I / F 301 receives packet identification information indicating a packet switching device that is a start point and an end point of a packet path. The route control unit 304 further calculates a packet path based on the network configuration information and the packet identification information. The setting unit 305 sets the packet path calculated by the route control unit 304 using the packet switching device 200.

In this case, it is possible to set the wavelength path and the packet path while taking into consideration the path restrictions and wavelength restrictions of the wavelength path.

(Third embodiment)
The wavelength network operation device 300 is separate from the wavelength switching device 100 and the packet switching device 200 in the first embodiment and the second embodiment, but in this embodiment, the wavelength switching device 100 or the packet switching is performed. It is incorporated in the device 200. In this case, the wavelength network operation apparatus 300 uses a distributed protocol such as GMLS (Generalized Multi-Protocol Label Switching) to transmit the device identification information and the method to the wavelength network operation apparatus 300 in the wavelength switching apparatus 100 or the packet switching apparatus 200. By notifying the path information and the in-device configuration information, the wavelength path and the packet path can be set.

As described above, the present invention has been described with reference to the embodiment, but the present invention is not limited to the above embodiment. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

For example, an input device such as a keyboard may be used as the user I / F 301 so that a wavelength network operator can directly input a setting request to the user I / F 301 without using a remote terminal.

The present invention can be implemented in a network operation management device that manages paths in a network management system (NMS) that manages a network, a control unit of a communication device in a network, or the like.

This application claims priority based on Japanese Patent Application No. 2009-187211, filed on Aug. 12, 2009, the entire disclosure of which is incorporated herein.

Claims

A plurality of wavelength path switching devices capable of switching the connection between the optical signal paths for each wavelength of the optical signal using an optical switch set the wavelength path of the wavelength network connected through the plurality of paths. A network management device that
An acquisition means for acquiring network configuration information indicating a connection relationship between each wavelength path switching device, and intra-device configuration information indicating a connection relationship between each optical path of each wavelength path switching device and each path;
Configuration conversion means for converting in-device configuration information acquired by the acquisition means into switchable route information indicating a path connectable to the path for each path;
Control means for calculating the wavelength path using the network configuration information acquired by the acquisition means and the switchable route information converted by the configuration conversion means,
A network management device comprising: setting means for setting the wavelength path calculated by the control means using each wavelength path switching device.
The network management device according to claim 1,
The in-device configuration information is a network management device that further indicates a wavelength of an optical signal that can be transmitted in each path.
The network management device according to claim 1 or 2,
Accepting means for receiving discrimination information for discriminating between the input path of the optical signal in the first wavelength path switching device of the wavelength path and the output path of the optical signal in the last wavelength path switching device of the wavelength path Further comprising
The control means includes
Based on the discrimination information and the switchable route information, the connection relationship of the wavelength path switching devices connected via the excluded route that is not connectable to the input route and the output route is represented by the network. Exclusion means to exclude from the configuration information;
A network management apparatus comprising: network configuration information from which the excluded route is excluded by the exclusion unit; and a calculation unit that calculates the wavelength path using the switchable route information.
The network management device according to claim 1 or 2,
Each wavelength path switching device is connected to a packet network having a plurality of packet switching devices capable of switching packet paths,
The network configuration information further indicates a connection relationship between each packet switching device and a connection relationship between each packet switching device and each wavelength path switching device,
Receiving means for receiving packet identification information indicating a packet switching device as a starting point and an ending point of the packet path;
The control means further calculates the packet path based on the network configuration information and the packet identification information,
The network management device, wherein the setting unit sets the packet path calculated by the control unit using the packet switching device.
In the network management device according to any one of claims 1 to 4,
The wavelength management network is a multi-ring network in which a plurality of ring networks having ring-shaped paths are connected to each other.
In the network management device according to any one of claims 1 to 5,
The network management device is a network management device built in the wavelength path switching device.
A plurality of wavelength path switching devices capable of switching the connection between the optical signal paths for each wavelength of the optical signal using an optical switch set the wavelength path of the wavelength network connected through the plurality of paths. A wavelength path setting method by a wavelength path setting method to
An acquisition step of acquiring network configuration information indicating a connection relationship between each wavelength path switching device and in-device configuration information indicating the configuration of the optical switch of each wavelength path switching device;
A configuration conversion step of converting the acquired in-device configuration information into switchable route information indicating a route connectable to the route for each route;
A control step of calculating the wavelength path using the acquired network configuration information and the converted switchable route information;
A setting step of setting the calculated wavelength path using each wavelength path switching device.
In the wavelength path setting method according to claim 7,
The in-device configuration information is a wavelength path setting method further indicating a wavelength of an optical signal that can be transmitted in each path.
The wavelength path setting method according to claim 7 or 8,
Accepting step for receiving discrimination information for discriminating between the input path of the optical signal in the first wavelength path switching device of the wavelength path and the output path of the optical signal in the last wavelength path switching device of the wavelength path Further including
The control step includes
Based on the discrimination information and the switchable route information, the connection relationship of the wavelength path switching devices connected via the excluded route that is not connectable to the input route and the output route is represented by the network. An exclusion step to exclude from the configuration information;
A wavelength path setting method comprising: calculating the wavelength path using the network configuration information from which the excluded route is excluded and the switchable route information.
The wavelength path setting method according to claim 7 or 8,
Each wavelength path switching device is connected to a packet network having a plurality of packet switching devices capable of switching packet paths,
The network configuration information further indicates a connection relationship between each packet switching device and a connection relationship between each packet switching device and each wavelength path switching device,
A reception step of receiving packet identification information indicating a packet switching device as a start point and an end point of the packet path;
In the control step, the packet path is further calculated based on the network configuration information and the packet identification information,
A wavelength path setting method in which, in the setting step, the calculated packet path is set using the packet switching device.