JP2003234768A - Network and node - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize speedy path setting in a GMPLS. <P>SOLUTION: In the network composed of an out node, an in node and a relay node installed in a route between these nodes, a request for securing a resource on the route and an action estimating the case of difficult securing of the relevant resource are sent from the out node. When it is difficult to secure the resource, the action received together with the request is carried out in the relay node. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention is used in an information communication network system. Especially GMPLS (Generalized M
ulti Protocol Label Switching) network.

[0002]

2. Description of the Related Art The next-generation network will start from a photonic cross connect (PXC) that switches optical paths.
It is composed of various nodes up to a router that forwards IP (Internet Protocol) packets. Such a different Switching Capability
In order to uniformly control the nodes with y, MPLS (Multi
GMP applied to the framework of Protocol Label Switching)
The standardization of the LS control plane is IETF (Interne
Engineering Task Force). In network path setup, messages for path establishment and maintenance are exchanged over the control channel, whereas in GMPLS the control channel does not necessarily physically match the data bearing link.

A conventional path setting procedure will be described with reference to FIG. In this specification, the source node and the destination node mean the node that sends a request for path setting prior to data transfer, and the node that terminates this request. It is called the receiving node. At the time of data transfer after the path is set, either the source node or the destination node can be the data source or the data destination. Further, the set path may be a unidirectional path or a bidirectional path.

The path setting request is issued by the node A on the originating side.
From the destination to the destination node D. When the relay node C cannot reserve the resource, the relay node C sends an error message to the originating node A,
Let us know about it. The originating node A performs rerouting based on this, and sends the request again to the destination node D.

[0005]

In the conventional path setting procedure, the process for securing the resource is executed in the relay node based on the request from the originating node, but the requested resource cannot be secured. In this case, an error is returned to the originating node, so there are many message round trips and it takes time to set the path.

The present invention has been made against such a background, and an object thereof is to provide a network, a node, a program, and a recording medium which can realize a quick path setting in GMPLS.

[0007]

According to the present invention, a node installed between a source node and a destination node is requested along with a request for resource reservation on a route from a source node to a destination node. (Hereinafter, referred to as a relay node) is characterized by specifying an action when the resource cannot be secured.

Thus, even if the relay node cannot secure the resource as requested, the action associated with the request is executed so that the relay node is different from the original request, but the other specified by the action. The procedure can allocate resources and send the request to the terminating node without returning an error to the originating node.

That is, a first aspect of the present invention comprises a source node, a destination node, and a node installed on a path between the source node and the destination node. ,
The originating node is provided with means for transmitting a request for securing resources on the route, and the node installed on the route secures resources related to its own node based on the request and the request. Is relayed to the destination node, and the destination node secures resources related to its own node based on the request and sends a resource securing completion notification to the source node. When the resource for the request is difficult to secure, the means for relaying is a network including means for sending a notification indicating that fact to the originating node.

Here, a feature of the present invention is that the means for transmitting the request includes an action transmitting means for transmitting the action together with the request on the assumption that it is difficult to secure resources in the relaying means. Including, the relaying means is provided with means for executing the action received together with the request when it is difficult to secure the resource for the request.

A second aspect of the present invention is to provide a node on the originating side,
It is applied to a network including a destination node and a node installed on a route between the source node and the destination node, and secures resources on the route as the source node. A means for transmitting a request to do so, as a node installed on the path, a means for securing resources related to the own node based on the request and relaying the request toward the destination node, The destination node includes means for securing resources related to its own node based on the request and sending a resource securing completion notification to the originating node, and the relaying means is for securing resources for the request. When it is difficult, a node equipped with means for sending a notification indicating that fact to the originating node It is.

Here, the feature of the present invention resides in that the means for transmitting the request includes an action transmitting means for transmitting, together with the request, an action assuming that it is difficult to secure resources in the relaying means. Including, the relaying means is provided with means for executing the action received together with the request when it is difficult to secure the resource for the request.

According to a third aspect of the present invention, when installed in an information processing device, the information processing device has a source node, a destination node, the source node and the destination node. Is applied to a network provided with a node installed in a path between and, as a function corresponding to the node of the calling side, realizes a function of transmitting a request for securing resources on the path, As a function corresponding to the node installed on the route, it realizes a function of securing resources related to the own node based on the request and relaying the request to the destination node, which corresponds to the destination node. As a function,
When a resource for the request is difficult to be secured as a function of relaying a resource securing completion notification to the originating node while securing a resource related to the own node based on the request, It is a program that realizes the function of sending a notification indicating that fact to the originating node.

Here, the feature of the present invention resides in that, as a function for transmitting the request, an action transmitting function for transmitting an action assuming that it is difficult to secure resources in the relay function together with the request is provided. As a function of realizing and relaying, when it is difficult to secure a resource for the request, a function of executing the action received with the request is realized.

For example, the path is a wavelength path and the action is a wavelength conversion process. That is, when the relay node cannot secure the resource as requested, the relay node follows the action instruction to search for a vacant wavelength, and reserves the vacant wavelength as a resource by its own judgment. The request is further forwarded to the destination node according to the wavelength.

According to this, even if the wavelength path with the same wavelength cannot be consistently set from the source node to the destination node, it is possible to set the wavelength path with the required minimum number of wavelength conversions. Therefore, compared with the original request, although the transmission efficiency is somewhat lower, the error setting is not performed because the error is not returned, and the communication can be performed more efficiently than the conventional one.

For example, the path is a wavelength path and the action is a crankback process. That is, when the relay node cannot secure the resource as requested, the relay node returns the request to the immediately previous relay node according to the action instruction. The relay node to which the request is returned secures resources from the relay node to the relay node different from the relay node to which the request is returned or to the destination node.

Such a process is called a crankback process. To briefly explain the reason for performing the crankback process, the relay node that cannot secure the resource as requested has a high probability of congestion. There is a high possibility that it will be useless to try to secure resources again in such a relay node. Therefore, it is more likely that the request will be sent back to the previous relay node where the resources have already been secured, and then the resource securing will be tried again.

According to this, although the route may be detoured, the route setting time is shortened because no error is returned, and more efficient communication can be performed as compared with the conventional case.

For example, the path is a wavelength path and the action is IP routing processing. That is,
If the relay node cannot secure the resource as requested, the relay node reads the IP address from the packet storing the request according to the action instruction, and performs IP routing to the destination node. According to this, there is a possibility that the wavelength path of the same wavelength will be interrupted at the relay node once, but some route can be set up to the next relay node or destination node, so no error is returned, so the route setup time Is shortened, and more efficient communication can be performed as compared with the conventional case.

For example, the path is a wavelength path and the action is a random hop process. That is, when the relay node cannot secure the resource as requested, the relay node hands over the request to any of the nodes that can hand over the request according to the action instruction.

Such a process is called a random hop process. To briefly explain the reason why the random hop process is performed, the relay node that cannot secure the resource according to the request hands off the request to the node that can be handed at that point. . The node receiving this reads the destination of the request and transfers the request to the destination node. According to this, although the route may be detoured, the route setting time is shortened because no error is returned, and efficient communication can be performed as compared with the conventional case.

For example, the path is a wavelength path and the action is detour processing. That is, when the relay node cannot secure the resource as requested, the relay node transfers the request to the bypass route according to the action instruction. This detour route may be set in advance or may be set as needed, and either route may be used. According to this, although the route may be detoured, the route setting time is shortened because no error is returned, and efficient communication can be performed as compared with the conventional case.

As described above, according to the present invention, when it is difficult to secure the resource based on the request, the process for securing the resource is executed according to the action instruction.
Even if the resource is still not secured by this, the error is returned to the originating node for the first time, so the frequency of returning the error from the relay node to the originating node is reduced as compared with the conventional method, and the speed of GMPLS You can set the path.

In the networks and nodes of the present invention,
The action sending unit includes, for example, a unit for displaying the presence or absence of designation of the action associated with the request and the action content by a flag.

Further, in the program of the present invention, as the action sending function, for example, a function of displaying the presence or absence of the designation of the action associated with the request and the content of the action by a flag is realized.

A fourth aspect of the present invention is a recording medium readable by the information processing device, in which the program of the present invention is recorded. By recording the program of the present invention on the recording medium of the present invention, the information processing apparatus can install the program of the present invention using this recording medium. Alternatively, the program of the present invention can be installed in the information processing apparatus directly from a server holding the program of the present invention via a network.

As a result, the information processing device such as a computer can realize a network and a node that can realize a quick path setting in GMPLS.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A network and a node according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram of the originating node of this embodiment. Figure 2
FIG. 3 is a block diagram of a relay node of this embodiment. Figure 3
FIG. 3 is a block configuration diagram of a receiving-side node according to the present embodiment. FIG. 4 is a block diagram of the request packet of this embodiment. FIG. 5 is a flowchart showing the operation of the relay node of this embodiment. FIG. 6 is a diagram showing a processing procedure when the action instruction of this embodiment is the wavelength conversion processing and the IP routing processing. FIG. 7 is a diagram showing a processing procedure when the action instruction of the present embodiment is crankback processing.
FIG. 8 is a diagram showing a processing procedure when the action instruction of this embodiment is the random hop processing and the default route processing.

As shown in FIG. 6, the present embodiment comprises a source node A, a destination node D, and relay nodes B and C. The source node A is shown in FIG. As described above, the request sending unit 1 for sending a request for securing resources on the path is provided, and the relay nodes B and C are provided with
As shown in FIG. 5, a resource securing unit 2 that secures resources related to its own node based on the request and relays the request to the destination node D is provided. A resource securing unit 2 that secures resources related to nodes and sends a resource securing completion notification to the originating node A.
And a resource notification unit 2 provided with a reserve notification transmission unit 3.
Is a network that sends a notification indicating that to the requesting node A when it is difficult to secure resources for the request.

Here, the feature of this embodiment is that
The originating node A is provided with an action setting unit 4 for sending an action, which is assumed when it is difficult to secure resources in the relay nodes B and C, together with the request, and the relay nodes B and C respond to the request. When it is difficult to secure resources, the action execution unit 5 for executing the action received with the request is provided. Request sending unit 1
Receives the action instruction set in the action setting unit 4, and sends this action instruction together with the request.

Further, the reserve notification transmitted from the reserve notification transmitting unit 3 of the destination node D is relay nodes C and B.
The resource securing unit 2 of (1) reaches the request sending unit 1 of the originating node A via the reverse direction of the request, and the originating node A recognizes the resource securing of the route.

In the present embodiment, for the sake of convenience of description, the originating node A, the relay nodes B, C, E, and the terminating node D are expressed as if they have different configurations. A node having the same configuration realizes each node configuration according to its own role.

The operation of the relay nodes B and C is shown in FIG. In the node A of this embodiment, the request sending unit 1
As shown in FIG. 4, a request packet is transmitted. The example of FIG. 4A is an example in which the action content is directly added to the request and transmitted. The example in FIG. 4B is an example in which the action content is designated by a flag. In the example of FIG. 4B, three actions of wavelength conversion, crankback, and detour processing are designated. In this way, multiple related actions can be specified at the same time. That is,
In the example of FIG. 4B, an action of “crank back to perform detour processing, but wavelength conversion may be performed at that time” is compositely designated.

As shown in FIG. 5, when the resource securing unit 2 receives the request, it tries to secure the resource (step 1). If the resource cannot be secured in step 1 (step 2), it is checked whether or not there is an action instruction by referring to the flag shown in FIG. 4, and if there is an action instruction (step 3), the designated action is performed. Is executed (step 4). If there is no designated action, an error is returned to the originating node A as in the conventional case (step 5).

The nodes in the network of this embodiment can be realized by a computer device which is an information processing device. That is, by being installed in a computer device, the computer device is applied to a network including a source node A, a destination node D, and relay nodes B and C, and is suitable for the source node A. As a function to perform, a function corresponding to the request transmission unit 1 that transmits a request for securing resources on the path is realized, and the nodes B and C installed on the path are realized.
As a function corresponding to the above, the function corresponding to the resource securing unit 2 that secures the resource related to the own node based on the request and relays the request to the destination node D As a function to perform, a function corresponding to the resource securing unit 2 and the reserve notification transmitting unit 3 that secures the resource related to the own node based on the request and sends the resource securing completion notification to the originating node A is realized. As a function corresponding to the securing unit 2, when a resource for the request is difficult to secure, it is a program that realizes a function of sending a notification indicating that fact to the node A on the originating side. As a function corresponding to node A, if it is difficult to secure resources at relay nodes B and C, The function corresponding to the action setting unit 4 for sending an action assuming the above is realized, and as a function corresponding to the relay nodes B and C, when it is difficult to secure resources for the request, By installing a program that realizes the function corresponding to the received action execution unit 5 in the computer device, the computer device can be made to correspond to the nodes A to D of this embodiment.

By recording the program of this embodiment on the recording medium of this embodiment, the computer device can install the program of this embodiment using this recording medium. Alternatively, the program of this embodiment can be directly installed in a computer device from a server holding the program of this embodiment via a network.

As a result, the G
It is possible to realize a network and a node that can realize quick path setting in MPLS.

(First Embodiment) A first embodiment will be described with reference to FIG. In the first embodiment, the path is a wavelength path and the action is a wavelength conversion process. That is,
As shown in FIG. 6, when the relay node C cannot secure the resource as requested, the relay node C searches for a vacant wavelength according to the action instruction, and determines the vacant wavelength by its own judgment. It is reserved as a resource, and the request is further transferred to the node D on the destination side by this free wavelength.

According to this, even if the wavelength path with the same wavelength cannot be consistently set from the node A on the sending side to the node D on the receiving side, it is possible to set the wavelength path with the minimum required number of wavelength conversions. it can. Therefore, compared with the original request, although the transmission efficiency is somewhat lower, the error setting is not performed because the error is not returned, and the communication can be performed more efficiently than the conventional one.

(Second Embodiment) A second embodiment will be described with reference to FIG. In the second embodiment, the path is a wavelength path and the action is a crankback process. That is, as shown in FIG. 7, when the relay node C cannot secure the resource as requested, the relay node C returns the request to the immediately preceding relay node B according to the action instruction. The relay node B that has returned the request secures a resource from there to the relay node E that is different from the relay node C that has returned the request.

According to this, it is possible to set a route that bypasses the relay node C having a high probability of congestion and passes through another relay node E. Therefore, although the route may be detoured, the route setting time is shortened because no error is returned, and more efficient communication can be performed as compared with the conventional case.

(Third Embodiment) A third embodiment will be described with reference to FIG. In the third embodiment, the path is a wavelength path and the action is an IP routing process. That is, when the relay node C cannot secure the resource as requested, the relay node C reads the IP address from the packet storing the request in accordance with the action instruction, and sends the IP address to the destination node D. To route. According to this, there is a possibility that the wavelength path of the same wavelength is once interrupted at the relay node C, but some route can be set up to the destination node D, so that the route setting time is shortened by the amount of not returning an error, It is possible to perform efficient communication as compared with the related art.

(Fourth Embodiment) A fourth embodiment will be described with reference to FIG. In the fourth embodiment, the path is a wavelength path and the action is random hop processing. That is, when the relay node C cannot secure the resource as requested, the relay node C hands over the request to any of the nodes that can hand over the request according to the action instruction. In the example of FIG. 8, the node C hands the request to the node E, and the node E transfers the request to the node D. According to this, although the route may be detoured, the route setting time is shortened because no error is returned, and efficient communication can be performed as compared with the conventional case.

(Fifth Embodiment) A fifth embodiment will be described with reference to FIG. In the fifth embodiment, the path is a wavelength path and the action is detour processing. That is, when the relay node C cannot secure the resource as requested, the relay node C transfers the request to the bypass route according to the action instruction. In the example of FIG. 8, the bypass route is a route passing through the node E. This detour route may be set in advance or may be set as needed, and either route may be used. According to this, although the route may be detoured, the route setting time is shortened because no error is returned, and efficient communication can be performed as compared with the conventional case.

(Summary of Embodiment) As described above, in this embodiment, when it is difficult to secure a resource based on a request, a process for securing a resource is executed according to an action instruction. If the resource still cannot be secured by this, the node A on the sending side first issues an error.
Since the error is returned to the node A on the originating side from the relay nodes B and C, the frequency of errors is reduced as compared with the conventional method, and the GM
It is possible to realize quick path setting in PLS. Further, it is possible to specify a complex action by appropriately combining the actions described in the first to fifth embodiments.

[0047]

As described above, according to the present invention,
It is possible to realize a network and a node that can realize quick path setting in GMPLS.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a node on the calling side of the present embodiment.

FIG. 2 is a block configuration diagram of a relay node according to the present embodiment.

FIG. 3 is a block configuration diagram of a destination node according to the present embodiment.

FIG. 4 is a configuration diagram of a request packet according to the present embodiment.

FIG. 5 is a flowchart showing the operation of the relay node of this embodiment.

FIG. 6 is a diagram showing a processing procedure when the action instruction of the present embodiment is wavelength conversion processing and IP routing processing.

FIG. 7 is a diagram showing a processing procedure when the action instruction of the present embodiment is crankback processing.

FIG. 8 is a diagram showing a processing procedure when the action instruction of this embodiment is a random hop process and a default route process.

FIG. 9 is a diagram for explaining a conventional route setting procedure.

[Explanation of symbols]

1 Request sending part 2 Resource securing department 3 Reserve notification sending unit 4 Action setting section 5 Action execution section A to E nodes

Continued front page    (72) Inventor Naoaki Yamanaka             2-3-1, Otemachi, Chiyoda-ku, Tokyo             Inside Telegraph and Telephone Corporation F-term (reference) 5K030 GA03 HA10 HB29 HC15 JA11                       LB01 MB16

Claims (11)

[Claims] 1. A source node, a destination node, and a node installed on a path between the source node and the destination node, wherein the source node includes: A means for transmitting a request for securing a resource on the route is provided, and a node installed on the route secures a resource regarding its own node based on the request and directs the request to the destination node. Means for relaying, and the destination node includes means for securing resources related to the own node based on the request and transmitting a resource securing completion notice to the originating node, and relaying means When it is difficult to secure a resource for the request, the network has means for sending a notification indicating that fact to the originating node. In the network, the means for sending the request includes an action sending means for sending together with the request an action assuming a case where it is difficult to secure resources in the relaying means, and the means for relaying is a resource for the request. When it is difficult to secure the request, the network is provided with means for executing the action received with the request. 2. The present invention is applied to a network provided with a source node, a destination node, and a node installed on a path between the source node and the destination node, As a node of the node, a means for transmitting a request for securing a resource on the route is provided, and as the node installed on the route, a resource related to the own node is secured based on the request and the request is transmitted to the destination side. A relay unit for the node, the destination node includes a unit that secures resources related to the own node based on the request and sends a resource securing completion notification to the originating node; When it is difficult to secure resources for the request, the means for displaying a notification indicating that fact is the node on the originating side. In the node having means for transmitting to the request, the means for transmitting the request includes an action transmitting means for transmitting, together with the request, an action assuming a case where it is difficult to secure resources in the relaying means, the relay The means for performing includes a means for executing the action received together with the request when it is difficult to secure resources for the request. 3. When the information processing device is installed, the information processing device is installed in a source node, a destination node, and a path between the source node and the destination node. Applied to a network provided with a node, the function corresponding to the node of the originating side to realize the function of sending a request for securing resources on the path, to the node installed in the path As a corresponding function, it realizes a function of securing resources related to the own node based on the request and relaying the request toward the destination node, and as a function corresponding to the destination node, based on the request. Realize a function to secure resources related to the own node and send a resource securing completion notification to the originating node, As a function of relaying, when it is difficult to secure resources for the request, in a program that realizes a function of sending a notification indicating that fact to the originating node, as a function of sending the request, The action sending function that sends an action assuming the case where it is difficult to secure resources in the relay function together with the request is implemented, and when it is difficult to secure resources for the request as the relay function, the request is transmitted. A program that realizes a function of executing the action received together with the program. 4. The network according to claim 1, the node according to claim 2, or the program according to claim 3, wherein the path is a wavelength path and the action is a wavelength conversion process. 5. The network according to claim 1, the node according to claim 2, or the program according to claim 3, wherein the path is a wavelength path and the action is a crankback process. 6. The network according to claim 1, the node according to claim 2, or the program according to claim 3, wherein the path is a wavelength path and the action is an IP routing process. 7. The network according to claim 1, the node according to claim 2, or the program according to claim 3, wherein the path is a wavelength path and the action is a random hop process. 8. The network according to claim 1, the node according to claim 2, or the program according to claim 3, wherein the path is a wavelength path and the action is detour processing. 9. The network according to claim 1, or the node according to claim 2, wherein the action sending means includes means for displaying the presence or absence of designation of the action associated with the request and the content of the action by a flag. 10. The program according to claim 3, wherein, as the action sending function, a function of displaying the presence or absence of the designation of the action associated with the request and the content of the action by a flag is realized. 11. A recording medium readable by an information processing device, in which the program according to claim 3 or 8 or 10 is recorded.