JP2011097146A - Method and device for accommodating optical burst signal in roadm network - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manage sub-wavelength resources and associate and manage a plurality of sub-wavelength paths, in order to be able to stably transfer a TDM (Time Division Multiplex) optical burst signal sent out from an optical burst signal generator over an existing ROADM (Reconfigurable Optical Add/Drop Multiplexer) network. <P>SOLUTION: Each node in an optical network has a table where an empty band is managed for every link and every wavelength. A terminal requesting data transmission transmits a data transmission request control packet to a node. The control packet includes a group ID capable of uniquely identifying a transmission terminal and a transmission port. The node requested to conduct data transmission secures a requested wavelength and sets up a sub-wavelength path. A band assigned to the sub-wavelength path is subtracted from empty bands of a link and a wavelength where the sub-wavelength path is established, and the table is updated. In addition, the sub-wavelength path and the group ID are associated, and the updated table and association between the sub-wavelength path and the group ID are advertised to other nodes. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to management of optical networks. More particularly, the present invention relates to a method and apparatus for managing sub-wavelength resources and associating and managing a plurality of sub-wavelength paths in order to accommodate an optical burst signal in a ROADM (Reconfigurable Optical Add / Drop Multiplexer) network.

  As a wavelength resource management method, a method has been proposed in which each node floods the usage status (availability) of each wavelength resource using the OSPF protocol, and the network management system manages the wavelength resource based on the information. (Non-Patent Document 1).

  Further, as a method for associating a plurality of wavelength paths, a group wavelength path setting method for OBS / GMPLS (Patent Documents 1 and 2), a working and protecting path setting method (Non-Patent Document 2), etc. are proposed. Has been. However, both of these are techniques for setting a plurality of paths when the source and destination nodes are the same.

JP 2008-245223 A JP 2008-245224 A

"Experimental Demonstration of Interworking GMPLS with OBS Networks" H. Guo et al., OECC / IOOC2007, pp.306-307, 2007. IETF RFC 4872 "RSVP-TE Extensions in Support of End-to-End Generalized Multi-Protocol Label Switching (GMPLS) Recovery"

  When the optical burst signal transmitted from the optical burst signal generator is accommodated in the existing ROADM network, the TDM type optical burst signal is accommodated. In this case, each optical wavelength division multiplexed signal (WDM signal) is further divided by TDM (Time Division Multiplexing). Therefore, in addition to wavelength management, management of the band is required. Hereinafter, the wavelength of the WDM signal divided by TDM is referred to as a pseudo sub wavelength.

  However, in the conventional wavelength resource management method, only wavelength management is performed, and there is a problem that band management is not performed.

  An optical burst signal generation device that transmits an optical burst signal transmits burst-like signals having different wavelengths from one optical port, and is connected to different counter devices. That is, unlike wavelength path management in which one transponder is used for each normal wavelength, it is necessary to perform path management by associating a plurality of optical burst signal sub-wavelength paths set from the same port. For example, when the optical transmission device of the optical burst signal generation device fails, all connection lines are affected. Therefore, it is necessary to quickly recover the failure by minimizing the control message.

  However, the conventional wavelength path association technique has a problem that it is not managed by associating sub-wavelength paths.

  Therefore, in the present invention, a TDM type optical burst signal (a plurality of wavelengths are transmitted in a time division manner) transmitted from an optical burst signal generator can be stably transferred on an existing ROADM network. It is an object of the present invention to provide a method and apparatus for managing resources and managing a plurality of sub-wavelength paths in association with each other.

  In order to achieve the above object, a method for managing sub-wavelength resources according to the present invention provides an optical network that transmits an optical burst signal by optical wavelength division multiplexing that includes a plurality of nodes. A table for managing each free bandwidth, and a node of the optical network requested to transmit data secures the requested wavelength and sets a sub-wavelength path; and the sub-wavelength path is set Updating the table by subtracting the bandwidth allocated to the sub-wavelength path from the link and the free bandwidth of the wavelength, and advertising the updated table to a node of the optical network.

  A terminal requesting data transmission, transmitting a control packet requesting data transmission to a node of the optical network, including a group ID capable of uniquely identifying the transmitting terminal and the transmission port; and requesting data transmission The optical network node further associates the sub-wavelength path with the group ID, and advertises the association of the sub-wavelength path with the group ID to the optical network node. It is also preferable to manage paths in association with each other.

  A method for associating and managing a plurality of sub-wavelength paths in order to achieve the above object is a method in which, in an optical network that transmits an optical burst signal by optical wavelength multiplexing having a plurality of nodes, a terminal that requests data transmission is a transmitting terminal And a step of transmitting a control packet requesting data transmission to a node of the optical network including a group ID capable of uniquely identifying a transmission port and a node of the optical network requested to transmit data. Securing a wavelength and setting a sub-wavelength path; associating the sub-wavelength path with the group ID; and advertising the association between the sub-wavelength path and the group ID to a node of the optical network. .

  An apparatus for managing sub-wavelength resources to achieve the above object includes a table for managing a free bandwidth for each link and each wavelength in an optical network that transmits an optical burst signal by optical wavelength multiplexing including a plurality of nodes, and When the node of the optical network requested to transmit data secures the requested wavelength and sets the sub-wavelength path, the link to which the sub-wavelength path is set and the vacant bandwidth of the wavelength change to the sub-wavelength path. Means for updating the table by subtracting the allocated bandwidth, and means for advertising the updated table to a node of the optical network.

  Further, when a terminal requesting data transmission transmits a control packet requesting data transmission including a group ID capable of uniquely identifying the transmitting terminal and the transmission port to the node of the optical network, It is also preferable to further comprise means for associating the group ID and means for advertising the association of the sub-wavelength path and the group ID to a node of the optical network, and managing a plurality of sub-wavelength paths in association with each other.

  An apparatus for managing a plurality of sub-wavelength paths in association with each other in order to achieve the above object, in an optical network that transmits an optical burst signal by optical wavelength multiplexing having a plurality of nodes, a terminal that requests data transmission is a transmitting terminal And a control packet for requesting data transmission, including a group ID that can uniquely identify the transmission port and the transmission port, and the node of the optical network requested to transmit data sets the requested wavelength. And means for associating the sub-wavelength path with the group ID when setting a sub-wavelength path, and means for advertising the association of the sub-wavelength path with the group ID to a node of the optical network.

  According to the present invention, an optical burst signal transmitted from an optical burst signal generator can be stably transferred on an existing ROADM network, and stable network resources can be managed.

The wavelength resource sharing type optical burst switch network model in this embodiment is shown. 3 shows a flowchart of a method for managing pseudo subwavelength resources in the present embodiment. An example of the method of managing the pseudo sub-wavelength resource in the present embodiment will be shown. An example of the sub wavelength resource management table in this embodiment is shown. 5 shows a flowchart of a method for managing group sub-wavelength paths in the present embodiment. An example of the method of managing the group sub-wavelength path of this embodiment is shown.

  The best mode for carrying out the present invention will be described in detail below with reference to the drawings.

  FIG. 1 shows a wavelength resource sharing type optical burst switch network model in the present embodiment. Wavelength resource sharing type optical burst switch network (OBS network) is virtually constructed on the existing all optical network by adding the function of the wavelength sharing type burst switching node to the ROADM of the existing all optical network. . For this reason, it becomes possible to implement a wavelength resource sharing type service while performing an existing network service. Since the OBS network is virtually constructed, the ROADM node also serves as an OBS network node (OBS core node).

  The OBS network is a network in which, when there is data to be transmitted, a certain wavelength is allocated for a time required for this data transmission, and the data to be transmitted is transmitted as an optical burst signal of the allocated wavelength. Includes OBS core nodes.

When there is data to be transmitted, the OBS edge node first transmits a control packet called BHP / BCP (Burst Header Packet / Burst Control Packet) at a wavelength allocated for the control packet. This control packet includes data destination information and wavelength information used by the data. The OBS edge node transmits an optical burst signal (DB: Data) of a wavelength for which data is notified by a control packet after a predetermined offset period has elapsed since the transmission of the control packet.
Burst).

  On the other hand, when the OBS core node receives the control packet, the OBS core node transfers the control packet based on the included destination information and transmits the optical burst signal received after the offset period elapses to the same path as the control packet.

  FIG. 2 shows a flowchart of a method for managing pseudo subwavelength resources in the present embodiment. A method for managing pseudo subwavelength resources will be described based on this flowchart.

  S21: When there is data to be transmitted, the OBS edge node transmits a control packet to the OBS core node.

  S22: The OBS core node secures the requested wavelength and sets a sub-wavelength path.

  S23: The control apparatus of the OBS core node has a table for managing sub-wavelength resources. This table exists for each link and has, for each wavelength, a free sub-wavelength resource indicating the maximum bandwidth of the wavelength and the free bandwidth of the wavelength. The control apparatus of the OBS core node subtracts the bandwidth allocated to the sub-wavelength path from the free link sub-wavelength resource of the requested link and wavelength. Note that the empty sub-wavelength resource becomes the maximum band of the wavelength when no sub-wavelength is set.

  S24: The control device of the OBS core node advertises the free resources of each link and each wavelength to other OBS core nodes using a control protocol such as OSPF. This advertisement is performed using a control plane. Thereby, sub-wavelength resources can be managed on the control plane.

  S25: The control device of the OBS core node transmits the free resources of each link and each wavelength to the upper network management system (NMS). Thereby, sub-wavelength resources of the entire network can be managed. For example, the network load status can be referred to by an operator inquiring to the network management system.

  FIG. 3 shows an example of a method for managing pseudo subwavelength resources in the present embodiment. In this network, OBS1, OBS2, and OBS3 exist as OBS edge nodes 1, and R1, R2, and R3 exist as ROADM nodes 2 that are OBS core nodes. Each ROADM node 2 has a management device 3 attached. These management apparatuses 3 are connected by a control plane, and a network management system (NMS) 4 is also connected to the control plane. Wavelengths from λ1 to λ40 are set for the optical fiber link connecting the ROADM node 2.

  When OBS1 transmits data to OBS3, R1, R2, and R3 of ROADM node 2 between OBS1 and OBS3 set a sub-wavelength path at wavelength λ39, and data is transmitted at this wavelength. Further, the management device 3 of the ROADM node 2 updates a table for managing the sub-wavelength resource. In this case, since the wavelength λ39 is assigned, the assigned bandwidth (2 Gbps) is subtracted from the maximum bandwidth (10 Gbps) of the wavelength λ39. Since the communication here passes through R1, R2, and R3 of the ROADM node 2, the table that manages the sub-wavelength resources of the link between R1 and R2 and the link between R2 and R3 is updated. The management device 3 of R1, R2, and R3 of the ROADM node 2 advertises the updated sub-wavelength resource management table using the control protocol, and further transmits it to the network management system 4. The management device 3 and the network management system 4 of the ROADM node 2 that have received the sub-wavelength resource management table update their own sub-wavelength resource management table.

  Next, when OBS2 transmits data to OBS3, R2 and R3 of ROADM node 2 between OBS2 and OBS3 set a sub-wavelength path at wavelength λ39, and data is transmitted at this wavelength. The management device 3 of the ROADM node 2 updates a table for managing sub-wavelength resources. In this case, since the wavelength λ39 is assigned, the assigned bandwidth (3 Gbps) is subtracted from the maximum bandwidth (10 Gbps) of the wavelength λ39. Since the communication here passes through R2 and R3 of the ROADM node 2, the table for managing the sub-wavelength resources of the link between R2 and R3 is updated. The management devices 3 of R2 and R3 of the ROADM node 2 advertise the updated sub-wavelength resource management table using the control protocol, and further transmit it to the network management system 4. The management device 3 and the network management system 4 of the ROADM node 2 that have received the sub-wavelength resource management table update their own sub-wavelength resource management table.

  FIG. 4 shows an example of a sub-wavelength resource management table in the present embodiment. FIG. 4A is a sub-wavelength resource management table before the above-described wavelength allocation, and corresponds to the link between R1 and R2 and the link between R2 and R3, respectively. FIG. 4B is a sub-wavelength resource management table after the wavelength allocation. Similarly, it corresponds to the link between R1 and R2 and the link between R2 and R3.

  In FIG. 4a, since the sub-wavelength path is not yet assigned to the wavelength λ39, the maximum bandwidth is 10 Gbps and the free sub-wavelength resource is 10 Gbps in both the link R1-R2 and the link R2-R3. In FIG. 4b, since the sub-wavelength path is assigned to the wavelength λ39, the maximum bandwidth is 10 Gbps and the free sub-wavelength resource is 8 Gbps in the sub-wavelength resource management table of the link R1-R2, and the sub-wavelength of the link R2-R3 In the resource management table, the maximum bandwidth is 10 Gbps, and the free subwavelength resource is 5 Gbps.

  As for these tables, all the control devices 3 of the ROADM nodes 2 have the same contents by the advertisement by the control brain, and the network management system 4 also has the same contents.

  As described above, in the wavelength resource sharing type optical burst switch network according to the present embodiment, each ROADM node 2 manages an empty sub-wavelength resource, so it is possible to assign a sub-wavelength path instead of a wavelength path with a large granularity. Thus, the bandwidth can be used efficiently.

  FIG. 5 shows a flowchart of a method for managing group sub-wavelength paths in the present embodiment. A method for managing group sub-wavelength paths will be described based on this flowchart.

  S51: If there is data to be transmitted, the OBS edge node transmits a control packet to the OBS core node. Note that a group ID is provided in this control packet.

  Here, the group ID is an ID that is the same only when the same device has the same port. For example, it is created by combining a device address and a port address. For this reason, it can be seen that sub-wavelength paths having the same group ID are assigned to the same port of the same transmitter.

  S52: The OBS core node secures the requested wavelength and sets a sub-wavelength path.

  S53: The control device of the OBS core node associates the set sub-wavelength path with the group ID in the control packet.

  S54: The controller of the OBS core node notifies the association between the sub wavelength path and the group ID to other OBS core nodes by exchanging the sub wavelength path setting message. This message exchange is performed using the control plane. Thereby, the association between the sub-wavelength path and the group ID can be managed on the control plane. For example, sub-wavelength paths that are transmitted from the same device and the same port can be collectively managed by classifying the sub-wavelength paths by group IDs to form group sub-wavelength paths.

  S55: The control device of the OBS core node transmits the association between the sub-wavelength path and the group ID to the higher-level network management system (NMS). As a result, the network management system can manage a plurality of sub-wavelength paths having the same group ID as group sub-wavelength paths. In addition, it is possible to reroute or cancel each group in the event of a failure.

  FIG. 6 shows an example of a method for managing group sub-wavelength paths according to the present embodiment. In this network, OBS1, OBS2, and OBS3 exist as OBS edge nodes 1, and R1, R2, and R3 exist as ROADM nodes 2 that are OBS core nodes. Each ROADM node 2 has a management device 3 attached. These management apparatuses 3 are connected by a control plane, and a network management system (NMS) 4 is also connected to the control plane. Wavelengths from λ1 to λ40 are set for the optical fiber link connecting the ROADM node 2.

  In FIG. 6, a sub-wavelength path with a bandwidth of 100 Mbps using a wavelength λ39 is set between OBS1 and OBS3, and a sub-wavelength path with a bandwidth of 50 Mbps using a wavelength λ40 is set between OBS1 and OBS2. Further, since these two paths are set from the same port of OBS1, they are associated with the same group ID. Since the association between the sub wavelength path and the group ID is also sent to the network management system 4, the network management system 4 can manage the two wavelength paths as group sub wavelength paths. Further, when a failure occurs between the links R1 and R2, it is possible to reroute or cancel a group unit. Further, since the two wavelength paths use the same port, as shown on the left side of FIG. 6, only one wavelength is used at a certain time. Paths are not used at the same time.

  Moreover, all the embodiments described above are illustrative of the present invention and are not intended to limit the present invention, and the present invention can be implemented in other various modifications and changes. Therefore, the scope of the present invention is defined only by the claims and their equivalents.

1 OBS edge node 2 ROADM node 3 Management device 4 Network management system

Claims (6)

In an optical network that transmits an optical burst signal by optical wavelength multiplexing with a plurality of nodes,
The node of the optical network has a table for managing the free bandwidth for each link and each wavelength,
The node of the optical network requested to transmit data is
Securing the requested wavelength and setting the sub-wavelength path;
Updating the table by subtracting the bandwidth assigned to the sub-wavelength path from the link where the sub-wavelength path is set and the free bandwidth of the wavelength;
Advertising the updated table to nodes of the optical network;
A method for managing sub-wavelength resources, comprising: Transmitting a control packet requesting data transmission to a node of the optical network, the terminal requesting data transmission including a group ID capable of uniquely identifying the transmitting terminal and the transmission port;
The node of the optical network requested to transmit data is
Associating the sub-wavelength path with the group ID;
Advertising an association of the sub-wavelength path and the group ID to a node of the optical network;
The method for managing sub-wavelength resources according to claim 1, further comprising: managing a plurality of sub-wavelength paths in association with each other. In an optical network that transmits an optical burst signal by optical wavelength multiplexing with a plurality of nodes,
Transmitting a control packet requesting data transmission to a node of the optical network, the terminal requesting data transmission including a group ID capable of uniquely identifying the transmitting terminal and the transmission port;
The node of the optical network requested to transmit data is
Securing the requested wavelength and setting the sub-wavelength path;
Associating the sub-wavelength path with the group ID;
Advertising an association of the sub-wavelength path and the group ID to a node of the optical network;
A method of associating and managing a plurality of sub-wavelength paths, comprising: In an optical network that transmits an optical burst signal by optical wavelength multiplexing with a plurality of nodes,
A table for managing free bandwidth for each link and each wavelength;
When the node of the optical network requested to transmit data secures the requested wavelength and sets the sub-wavelength path, the link to which the sub-wavelength path is set and the vacant bandwidth of the wavelength change to the sub-wavelength path. Means for updating the table by subtracting the allocated bandwidth;
Means for advertising the updated table to a node of the optical network;
A device for managing sub-wavelength resources, comprising: When a terminal requesting data transmission transmits a control packet requesting data transmission to a node of the optical network including a group ID that can uniquely identify the transmitting terminal and the transmission port,
Means for associating the sub-wavelength path with the group ID;
Means for advertising the association of the sub-wavelength path and the group ID to a node of the optical network;
5. The apparatus for managing sub-wavelength resources according to claim 4, further comprising a plurality of sub-wavelength paths that are associated with each other and managed. In an optical network that transmits an optical burst signal by optical wavelength multiplexing with a plurality of nodes,
A terminal requesting data transmission transmits a control packet requesting data transmission including a group ID capable of uniquely identifying the transmitting terminal and the transmission port to the node of the optical network, and the optical transmission requested to transmit data When the network node secures the requested wavelength and sets the sub-wavelength path,
Means for associating the sub-wavelength path with the group ID;
Means for advertising the association of the sub-wavelength path and the group ID to a node of the optical network;
An apparatus for managing a plurality of sub-wavelength paths in association with each other.

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