JP2003258866A - Optical path network, node, program and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the labor and time required for setting a cut-through path and the possibility of ineffective holding. <P>SOLUTION: In order to increase the occupying rate of a section using the cut-through path in a path between a node on an originating side and a node on an incoming side, a plurality of paths are set between the node on the originating side and the node on the incoming side in advance and statistical information on the occupying rate of the section using the cut-through path from among a plurality of the paths is collected. Then, a path maximizing the occupying rate of the section using the cut-through path is selected. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention is used for burst data transfer in an IP network. The present invention can also be applied when transferring an optical packet for signaling performed prior to setting an optical path in an IP network.

[0002]

2. Description of the Related Art In data transfer in an IP (Internet Protocol) network, a router as a node reads the header information of an IP packet and sends the IP address to the destination route.
Forward the packet. This is repeated among a plurality of nodes, and as a result, the IP packet reaches the desired destination. In such an IP packet transfer method, individual I
Since the transfer is performed in P packet units, it is necessary to read the header information of each individual IP packet.

On the other hand, in recent years, the demand for a series of large-volume data transfer such as moving image data is rapidly increasing. Such a series of large amount of data is called burst data, and is divided into a large number of IP packets and accommodated. For such burst data transfer, it is inefficient to perform the transfer in units of individual IP packets, so a cut-through path is set between specific nodes. The transfer is performed at once without reading the header information. Especially, it is effective for data transfer using the optical path.

That is, in data transfer using an optical path as a transmission path between nodes, each node temporarily converts an optical signal that has arrived through the optical path into an electrical signal, reads header information of an IP packet, After the destination route is determined, it is necessary to convert the optical signal again and send it to the optical path again. On the other hand, in the data transfer using the cut-through path by the wavelength path, it is not necessary to convert the optical signal into an electrical signal once to read the header information, and the optical signal can be transferred as it is from the start point to the end point of the cut-through path. , Very efficient burst data transfer can be performed.

[0005]

As described above, the cut-through path is optimum for burst data transfer using the wavelength path, but it is necessary to set the cut-through path in advance prior to burst data transfer. Become.

That is, a request for setting a cut-through path is sent from the source node to the destination node. The request packet in which this request is stored is an IP packet, and arrives at the destination node while the header information is read by each node. In the middle of this
When it is difficult to set the cut-through path due to lack of network resources or the like, a signal for notifying the fact is sent to the originating node. In response to this, the node on the sending side retries the setting of the cut-through path or gives up.

Further, it is desirable that the cut-through path be connected from the source node to the destination node by a single line, but depending on the distance between the source node and the destination node, the optical signal Signal quality deterioration due to loss and crosstalk becomes significant, and 3R (Reshaping, Retim
ing, Regenerating) processing may be required and 3R
It is necessary to calculate which node will perform the process.

As described above, the cut-through path itself is optimal for burst data transfer, but the user who is the data transmission source secures network resources in consideration of the data amount of the data to be transmitted. There is a problem that it is necessary to set the cut-through path, and the setting procedure takes time.

Also, the cut-through path is set successfully,
The cut-through path is released after the burst data transfer is performed, but unless the user who is the data transmission source sends a release request, the cut-through path is not released, and the cut-through path can be suspended pending. I can't deny the sex.

Further, conventionally, a single route for transmitting burst data from the originating node is defined by a predetermined policy. For example, based on the policy of “making the shortest route the optimum route”, burst data is transmitted to the route having the shortest distance between the source node and the destination node. Then, the relay node on that path determines whether or not resources can be secured.

As described above, conventionally, it is difficult to secure resources on one route determined by a predetermined policy, and it is difficult to secure resources. Even when the node on the sending side retries, the retry is performed on the same route. It is being appreciated.

The present invention has been made under such a background, and is based on a policy that a plurality of routes are set as route candidates for resource reservation, and resource reservation may be successful in any one of them. An object of the present invention is to provide an optical path network, a node, a program, and a recording medium capable of increasing the success rate of cut-through path setting by securing resources and achieving quick cut-through path setting and effective use of resources. Another object of the present invention is to provide an optical path network, a node, a program, and a recording medium that can reduce the labor and time required for setting a cut-through path and the invalid hold.

In the present specification, the source node and the destination node are called the source node that sends a request for path setting prior to data transfer, and the termination destination of this request. This node is called the destination 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.

[0014]

The present invention is characterized in that cut-through path setting need not be performed prior to burst data transfer. Further, the present invention is characterized in that the cut-through path is released immediately after the burst data transfer is completed. Furthermore, the present invention is characterized in that it is not necessary to calculate in advance the location where 3R processing is required. As a result, it is possible to reduce the labor and time required for setting the cut-through path and the invalid hold.

Further, according to the present invention, in order to increase the ratio of the section using the cut-through path in the route between the source node and the destination node, the source node and the destination node are connected. A plurality of routes are set in between, statistical information about the ratio of the section using the cut-through path is taken from the plurality of routes, and the path with the largest ratio of the section using the cut-through path is selected.

When setting a plurality of route candidates between the originating side node and the destination side node, for example, when there are a plurality of equidistant route candidates, a route candidate with the shortest distance is selected. Alternatively, if there are a plurality of route candidates having different distances, the plurality of route candidates are selected in order from the route candidate having the shortest distance.

That is, a first aspect of the present invention is an optical path network, and features of the present invention are that a source node, a destination node, the source node and the destination node. And a relay node installed on the path between the relay node and the node
A means for setting an optical path according to the P address is provided,
This optical path setting means detects the arrival of the first packet of burst data, and sets the cut-through path to the next-stage relay node when the arrival of the first packet of burst data is detected by this detection means. Cut-through path setting means, means for detecting arrival of the last packet of burst data, and when the arrival of the last packet of burst data is detected by this detecting means, the cut-through path already set is passed through the last packet. A cut-through path releasing means to be released later, wherein the cut-through path setting means determines whether or not the cut-through path up to the relay node in the next stage can be set, and the determination result of this determining means is the source node. If the judgment result of the judgment means and the judgment result of the judgment means cannot be set Is provided with means for temporarily accumulating incoming burst data, and IP transfer means for individually transferring each packet constituting the burst data accumulated in the temporarily accumulating means according to its IP address. Between the node and the destination node,
A plurality of routes are set in advance, and the originating node calculates the cut-through path setting success rate by the cut-through path setting unit according to the determination result notified by the notification unit regarding the plurality of routes, respectively. , Means for transmitting burst data to a route having a high cut-through path setting success rate according to the calculation result of the calculating means.

A second aspect of the present invention is the originating node, which is characterized by the fact that when the relay node detects the arrival of the first packet of burst data, the cut-through path is relayed to the next stage. When the node is set and the arrival of the last packet of burst data is detected, the already set cut-through path is released after the passage of the last packet, and at this time, whether the cut-through path to the next-stage relay node can be set or not And notifies the originating node of this determination result. If the determination result cannot be set, the burst data that arrives is temporarily stored, and the individual packets that make up this accumulated burst data are assigned to their IP addresses. According to the relay node for a plurality of routes to the destination node. According to the notified determination result, means for respectively calculating the cut-through path setting success rate, and means for transmitting the burst data to the route having a high cut-through path setting success rate according to the calculation result of the calculating means are provided. is there.

A third aspect of the present invention is a program, which is characterized by being installed in an information processing device so that the relay node arrives at the information processing device at the start packet of burst data. When detecting the, the cut-through path is set up to the relay node in the next stage, and when the arrival of the last packet of burst data is detected, the already set cut-through path is released after passing through the last packet. It is determined whether or not a cut-through path up to the relay node in the stage can be set, the result of this determination is notified to the originating node, and if the determination result cannot be set, incoming burst data is temporarily stored and this is stored. Provided in an optical path network that individually transfers individual packets that make up burst data according to their IP addresses As a function corresponding to the device for controlling the originating node, the function of calculating the cut-through path setting success rate according to the determination result notified by the relay node for a plurality of routes to the destination node, The function of transmitting burst data to a route having a high cut-through path setting success rate is realized according to the calculation result of this calculation function.

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, it is possible to realize an optical path network and a node using an information processing device such as a computer device, which can reduce the labor and time required for setting the cut-through path and the invalid hold.

As described above, according to the present invention, the cut-through path is not set in advance, but the cut-through path is set to a place where it can be set together with the transfer of the burst data, and when it becomes difficult to set the cut-through path. ,
It is characterized by switching to IP transfer. This allows
The present invention is characterized in that the cut-through path setting need not be performed prior to the burst data transfer, and the labor and time required for setting the cut-through path can be reduced.

For example, the subsequent burst data amount information is written as the header information of the leading packet, and the means for detecting the arrival of the leading packet refers to the succeeding burst data amount information to start the burst data. Means may be provided for detecting packets. At this time, the burst data amount information is, for example, packet number information or packet length information that follows the head packet.

Further, for example, as the header information of the final packet, information indicating that the packet is the final packet of burst data is written, and the means for detecting the arrival of the final packet is the final packet. Means may be provided for detecting the last packet of burst data with reference to information indicating that there is.

As a result, the present invention is characterized in that the cut-through path is released immediately after the burst data transfer is completed, and the invalid hold of the cut-through path can be reduced.

The means for determining whether or not the setting is possible is, for example, the presence / absence of a vacant wavelength for setting a cut-through path to the node in the next stage, the allowable transfer rate to the own node, and the permission to the node in the next stage Means for determining the difference between the transfer rate and the signal quality of the burst data are provided.

Further, when it is determined that the cut-through path cannot be set by the means for determining whether the setting is possible due to the deterioration of the signal quality of the first packet of the incoming burst data, the fact is notified to the preceding node. It is desirable that a means is provided, and means for 3R-processing the incoming burst data according to the notification by the notification means.

According to this, it is not necessary to calculate in advance the portion to be subjected to the 3R processing, and the 3R processing may be performed at the time when the signal quality deterioration occurs. Therefore, the labor and time required for setting the cut-through path can be reduced. Can be reduced.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical path network according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a conceptual diagram of the optical path network of this embodiment. FIG. 2 is a block diagram of the optical path setting unit of this embodiment. FIG. 3 is a block diagram of the cut-through path setting unit of this embodiment. FIG. 4 is a block diagram of a node on the calling side of this embodiment. FIG. 5 is a flowchart showing the setting success rate calculation flow of the first embodiment. FIG. 6 is a flowchart showing the setting success rate calculation flow of the second embodiment. FIG. 7 is a block diagram of the first packet of burst data according to the present embodiment. FIG. 8 is a block diagram of the final packet of burst data in this embodiment. FIG. 9 is a diagram for explaining the 3R processing configuration of this embodiment. FIG. 10 is a view for explaining the arrangement of the 3R trunks of this embodiment.

In the present embodiment, as shown in FIG. 1, a relay installed on a route between a source node A, a destination node N, and a source node A and a destination node N. Node B ~
M, and each of the relay nodes B to M includes an optical path setting unit 1 that sets an optical path according to the IP address of an incoming IP packet. The optical path setting unit 1 is, as shown in FIG. A burst data head detection unit 11 for detecting the arrival of the head packet of burst data, and when the arrival of the head packet of the burst data is detected by this burst data head detection unit 11, a cut-through path is set up to the next relay node. Cut-through path setting section 1
2, a burst data end detection unit 13 that detects the arrival of the last packet of burst data, and when this burst data end detection unit 13 detects the arrival of the last packet of burst data, the cut-through path that has already been set is set. The cut-through path release unit 14 releases the cut-through path after passing the final packet, and the cut-through path setting unit 12 determines whether or not the cut-through path up to the relay node at the next stage can be set, as shown in FIG. The determination unit 22 and the determination result notifying unit 28 that notifies the determination result of the cut-through path setting availability determination unit 22 to the originating node A, and the determination result of the cut-through path setting availability determination unit 22 when the setting is not possible Burst data buffer 24 for temporarily storing burst data
And an IP transfer unit 25 for individually transferring individual packets constituting the burst data accumulated in the burst data buffer 24 according to the IP address thereof, and the node A on the originating side and the node N on the destination side. In between,
As shown in FIG. 4, a plurality of routes # 1, # 2, and # 3 are preset, and the originating node A uses the determination result notifying unit 28 for the routes # 1, # 2, and # 3 as illustrated in FIG. A setting success rate calculation unit 29 that calculates the setting success rate of the cut-through path by the cut-through path setting unit 12 according to the notified determination result, and a high cut-through path setting success rate according to the calculation result of the setting success rate calculation unit 29. Route selector 3 for sending burst data to the route
The optical path network is characterized by including 0 and 0.

(First Embodiment) A setting success rate calculation flow of the first embodiment of the present invention will be described with reference to FIG. The setting success rate calculation flow of the first embodiment is an embodiment for statistically calculating the cut-through path setting success rate of each of the routes # 1 to # 3 in the normal burst data transfer process. In the first embodiment,
The plurality of paths # 1, # 2, and # 3 shown in FIG. 1 are cyclically used each time burst data transfer occurs. That is, as shown in FIG. 5, when burst data transfer occurs,
For example, the route # 1 is used (step 1). If the cut-through path is successfully set in the burst data transfer process (step 2), the success count is incremented by 1 (step 3). If the cut-through path setting fails, the success count is decremented by 1 (step 4).
However, if the subtraction result is negative, it is set to zero. If a burst data transfer occurs next, route #
2 is used (step 6, step 1). As in the case of the route # 1, if the cut-through path is successfully set in the burst data transfer process, the success count is incremented by 1 (step 3). If the cut-through path setting fails, the success count is decremented by 1 (step 4). When burst data transfer occurs next,
The route # 3 is used (step 6, step 1). As in the case of the routes # 1 and # 2, if the cut-through path is successfully set in the burst data transfer process, the success count is incremented by 1 (step 3). If the cut-through path setting fails, the success count is set to 1.
Subtract (step 4). In this way, after the data has been acquired a predetermined number of times (step 5), routes # 1, # 2, #
(Success count / use count) × 100 (%) is calculated for each 3 (step 7), and the route with the maximum calculation result is selected as the route with the maximum cut-through path setting success rate (step 8). ).

By periodically executing such a setting success rate calculation flow and transferring the burst data by using the path selected as a result, it is possible to use a path having a high cut success path setting success rate. it can.

In this embodiment, when the cut-through path setting fails, the burst data is accumulated in the burst data buffer 24 via the switch 21 at the relay node, and the IP transfer unit 25 transfers the IP data. Is done. Further, even during IP transfer, the setting unit 23 retries the setting of the cut-through path, and if the setting of the cut-through path is successful, the burst data accumulated in the burst data buffer 24 is cut through the switch 27. Sent to. At this time, if speed conversion is necessary, the speed conversion unit 26 can perform speed conversion.

Therefore, even if the cut-through path is successfully set in one bit, if the cut-through path is set once between the node on the calling side and the node on the called side without interruption, or once in the middle. Various situations are conceivable, such as when the cut-through path is interrupted and switched to the IP transfer, but then the cut-through path is set again and the transfer is returned to the cut-through path. The success means a state in which the source node and the destination node are all connected by the cut-through path as a result.

(Second Embodiment) A setting success rate calculation flow of the second embodiment of the present invention will be described with reference to FIG. The setting success rate calculation flow of the second embodiment is an embodiment in which a test packet for calculating the cut-through path setting success rate is sent to each of the routes # 1 to # 3 at the same time to statistically calculate the cut-through path setting success rate. Is. Compared with the first embodiment, since the test packet that is not related to the data transfer is used, the calculation can be performed at any time. That is, as shown in FIG. 6, the test packets are simultaneously transmitted to the routes # 1, # 2, and # 3 (step 1). If the cut-through path is successfully set in the process of transferring the test packet (step 2), the success count is incremented by 1 (step 3). If the cut-through path setting fails, the success count is decremented by 1 (step 4). However, if the subtraction result is negative, it is set to zero. In this way, after the data has been acquired a predetermined number of times (step 5),
For each of the routes # 1, # 2, and # 3, (success count / test count) × 100 (%) is calculated (step 6), and the route with the maximum calculation result is set to the maximum cut-through path success rate. (Step 7).

By regularly executing such a setting success rate calculation flow and transferring the burst data using the path selected as a result, it is possible to use a path having a high cut success path setting success rate. it can.

(Other Embodiments) As the header information of the head packet, as shown in FIG. 7, the subsequent burst data amount information is written, and the burst data head detector 11
Detects the first packet of burst data by referring to the subsequent burst data amount information. The burst data amount information is packet number information or packet length information that follows the first packet.

As shown in FIG. 8, as the header information of the final packet, information indicating that the packet is the final packet of burst data is written, and the burst data end detection unit 13 uses this final packet. The last packet of burst data is detected by referring to the information indicating that there is a certain information.

The cut-through path setting availability determination unit 22
Whether or not there is a vacant wavelength for setting a cut-through path to the next node, the difference between the allowable transfer speed to the own node and the allowable transfer speed to the next node, and the signal quality of burst data are respectively judge.

The cut-through path setting availability determination unit 22
When it is determined that the cut-through path cannot be set due to the deterioration of the signal quality of the first packet of the incoming burst data, the fact is notified to the preceding node. As shown in FIG. 9, the node at the preceding stage includes a 3R trunk 31 that performs 3R processing on the burst data that arrives in accordance with this notification.

In the example of inserting the 3R trunk 31 shown in FIG. 10, the 3R trunk 31 is provided at the output port of the optical cross connect 33, and the cut through path that needs to be subjected to the 3R processing is the optical cross connect 33 for the 3R trunk. The trunk 31 is connected to the connected output port. The cut-through path that has been subjected to the 3R processing by the 3R trunk 31 is again connected to the input port of the optical cross connect 33 and output from the desired output port. 3R control unit 32
When receiving the signal quality deterioration notification, the device instructs the optical cross connect 33 to connect the cut-through path to the 3R trunk 31.

According to this, it is not necessary to calculate in advance the portion to be subjected to the 3R processing, and it is sufficient to perform the 3R processing at the time when the signal quality deterioration occurs. Therefore, the labor and time required for setting the cut-through path can be saved. Can be reduced.

The node of this embodiment can be realized by using a computer device which is an information processing device. In particular,
The device for controlling the originating node, which is a feature of this embodiment,
When installed in a computer device, the computer device has a plurality of routes # 1 to the destination node N as a function corresponding to the device controlling the source node provided in the optical path network of the present embodiment. , # 2,
According to the result of the setting success rate calculating unit 29, the function corresponding to the setting success rate calculating unit 29 that calculates the setting success rate of the cut-through path according to the determination result notified by the relay nodes B to M regarding # 3. By installing a program that realizes a function corresponding to the route selection unit 30 that sends burst data to a route with a high cut-through path setting success rate, the computer device controls the node on the originating side of this embodiment. It can be a device corresponding to the device. Further, a device that controls the relay nodes B to M and the destination node N can also be realized by using a computer device, but this is an existing technique, and a description thereof will be omitted.

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.

Thus, using the computer device,
It is possible to realize an optical path network and a node that can reduce the labor and time required for setting a cut-through path and the invalid hold.

[0046]

As described above, according to the present invention,
It is possible to reduce the labor and time required for setting the cut-through path and the invalid hold.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of an optical path network according to an embodiment.

FIG. 2 is a block configuration diagram of an optical path setting unit according to the present embodiment.

FIG. 3 is a block configuration diagram of a cut-through path setting unit of this embodiment.

FIG. 4 is a block configuration diagram of a node on the calling side of the present embodiment.

FIG. 5 is a flowchart showing a setting success rate calculation flow of the first embodiment.

FIG. 6 is a flowchart showing a setting success rate calculation flow of the second embodiment.

FIG. 7 is a configuration diagram of a first packet of burst data according to the present embodiment.

FIG. 8 is a configuration diagram of a final packet of burst data according to the present embodiment.

FIG. 9 is a diagram for explaining the 3R processing configuration of the present embodiment.

FIG. 10 is a diagram for explaining the arrangement of the 3R trunk according to the present embodiment.

[Explanation of symbols]

1 Optical path setting section 11 Burst data start detector 12 Cut-through path setting section 13 Burst data end detector 14 Cut-through path release section 21, 27 switch 22 Cut-through path setting availability judgment unit 23 Setting section 24 burst data buffer 25 IP transfer unit 26 Speed converter 28 Judgment result notification section 29 Setting success rate calculator 30 Route selector 31 3R trunk 32 3R control unit 33 Optical Cross Connect A to N nodes

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kohei Shiomoto             2-3-1, Otemachi, Chiyoda-ku, Tokyo             Inside Telegraph and Telephone Corporation F term (reference) 5K030 GA03 HA08 HB11 JL03 LB01                       LB05 LE14

Claims (4)

[Claims] 1. A source node, a destination node, and a relay node installed on a path between the source node and the destination node, and the relay node arrives. A means for setting an optical path according to the IP address of the IP packet is provided. The means for setting the optical path includes means for detecting the arrival of the first packet of burst data and arrival of the first packet of the burst data by this detecting means. When is detected, the cut-through path setting means for setting the cut-through path to the next-stage relay node, the means for detecting the arrival of the last packet of burst data, and the detection means for detecting the arrival of the last packet of burst data. When the above is set, the cut-through path that releases the already set cut-through path after passing the final packet The cut-through path setting means, means for judging whether or not the cut-through path up to the next-stage relay node can be set, and means for notifying the judgment result of this judging means to the originating node. And a means for temporarily accumulating incoming burst data when the judgment result of the judgment means is not set, and individual packets constituting the burst data accumulated in the temporarily accumulating means according to the IP address thereof. A plurality of routes are preset between the source node and the destination node, and the source node notifies the plurality of routes about the routes. The cut-through path setting success rate by the cut-through path setting means is calculated in accordance with the determination result notified by the means. Stage and the light path network, characterized in that a means for transmitting the burst data to the high cut-through path set success rate path according to the calculation result of the means for this calculation. 2. When the relay node detects the arrival of the first packet of the burst data, the cut-through path is set up to the next-stage relay node, and when the arrival of the last packet of the burst data is detected, the cut already set. When the through path is released after passing the final packet, at this time, it is determined whether or not the cut-through path up to the relay node in the next stage can be set, the result of this determination is notified to the originating node, and the determination result cannot be set. Is provided in the optical path network that temporarily stores the incoming burst data and individually transfers the individual packets that make up the accumulated burst data according to their IP addresses. Regarding multiple routes to the destination node, According to the judgment result notified by the relay node, the success rate of setting the cut-through path is set. Means for calculating, originating node, characterized in that a means for transmitting the burst data to the high cut-through path set success rate path according to the calculation result of the means for this calculation. 3. When installed in an information processing device, when the relay node detects arrival of the first packet of burst data in the information processing device, a cut-through path is set up to the relay node at the next stage, and the cut-through path is set. When the arrival of the final packet is detected, the already set cut-through path is released after passing the final packet, and at this time, it is determined whether or not the cut-through path to the relay node at the next stage can be set, and this determination result is An optical path for notifying the originating node and temporarily accumulating incoming burst data when the judgment result cannot be set, and individually transferring individual packets constituting the accumulated burst data according to their IP addresses. As a function corresponding to the device controlling the originating node provided in the network, the destination node Function for calculating the cut-through path setting success rate according to the judgment result notified by the relay node for a plurality of routes in step 1, and burst data for a route with a high cut-through path setting success rate according to the calculation result of this calculating function. A program that realizes the function of sending out. 4. A recording medium readable by the information processing device, in which the program according to claim 3 is recorded.