JP3734817B2 - Routing device and program - Google Patents

Description

The present invention provides a packet network or TDM (Time Division).
Multiplexing) or wavelength path network. In particular, it relates to a route control technique.

  FIG. 7 shows the relationship between the path control device and the network. A path control device is provided for each node. First, a conventional example in an IP network will be described using a node as an IP router.

  Routing in an IP network, that is, IP routing, is a technique for creating a routing table, and is an important technique for the Internet to operate in a distributed manner and develop on a large scale. Since the Internet is large-scale, it is not practical to create a routing table by centrally managing destination addresses. Therefore, a routing protocol has been developed as a mechanism for creating a routing table in an autonomous and distributed manner.

  In the routing protocol, routers create a routing table while exchanging information, and based on this routing table, create a forwarding table used for IP packet transfer. In addition, the routing table is dynamically changed in accordance with a change in the network state or a change in the operation policy.

  Routing protocols are classified into several types in terms of operating principles. Distance vector type, path vector type, link state type, etc. FIG. 8 shows an outline of the classification and operation principle of each type of routing protocol.

  In the distance vector type, each router exchanges a distance vector (destination address, distance to the destination address, and next hop router), updates its distance vector table based on the distance vector for each destination address from neighboring routers, The next hop information is calculated for each destination address. In the distance vector type, the size of the network is limited to solve the routing table problem.

  In the path vector type, by replacing the path vector instead of the distance vector, the problem of the routine group that is a problem in the distance vector type is solved and the network scale is not limited.

  In the link state type, the network state is shared among all routers by exchanging the link state between routers, and each router calculates the shortest path to the destination address on the topology.

  Since the present invention relates to distance vector type path control, distance vector type path control will be described. In the distance vector type, each router exchanges a distance vector table (a table in which distances for each destination and neighboring routers are written) with neighboring routers to create a routing table. FIG. 9 shows a distance vector table (a distance vector table records a distance for each destination and a set of links to adjacent routers used at that time).

  The distance vector type is designed based on the Bellman-Ford algorithm. First, the protocol operates assuming that each router knows the cost of a link with an adjacent router. In other words, only the cost of the neighboring router and the link to it is written in the distance vector.

  Each router exchanges the distance vector table with the neighboring router, and if a distance vector obtained from the neighboring router can be reached at a shorter distance than its own distance vector with respect to a certain destination set, it is used. Update your distance vector. When each router updates the distance vector, it notifies the neighboring router again. As each router continues to update the distance vector table in an autonomous and distributed manner, the content of the distance vector table eventually converges. The route according to the converged distance vector table is the shortest route. FIG. 10 shows a conceptual diagram of the distance vector type operation. In FIG. 10, router X gets a status vector table (destination = A, next hop = B, distance = 50) from router B, and router C is empty (destination = A, next hop = C, distance = 100). Get. Thus, it can be seen that the router X can reach the router A at a cost of 52 (= 50 + 2) via the adjacent router B and 101 (= 100 + 1) through the adjacent router C. Therefore, the router X adopts the adjacent router B as the next hop when going to the router A.

In the Bellman-Ford algorithm, each node updates the distance vector table based on the Bellman formula shown below. If the link cost between adjacent nodes i and j is d (i, j) and the shortest distance from node i to destination node at time t is D (t, i), node i is node j When the distance vector is obtained from the shortest distance D (t + δ, i) at the next moment,
D (t + δ, i) = min (D (t, i), d (i, j) + D (t, j)) (1)
Given in. The next hop information to the destination node constituting the distance vector is rewritten with the one selected by min (). In FIG. 11, an attempt is made to obtain the shortest path from the source node i to the destination node. It is assumed that the source node i at time t can reach the shortest route to the destination node at a cost of D (t, i). Here, it is assumed that the adjacent node j has notified the node i that the shortest route to the destination node can be reached at the cost D (t, j). Nodes i and j are adjacent to each other, and the cost of the link connecting them is assumed to be d (i, j). At this time, the node i selects the smaller of D (t, j) and d (i, j) + D (t, j).

  The Bellman-Ford algorithm is proved that the initial value D (0, i) and the adjacent link cost dij are arbitrary positive values and converges to the shortest path even when the distance vector table is exchanged asynchronously. . Since each router may asynchronously exchange the distance vector table and update the distance vector table, the algorithm in this case is particularly called an asynchronous distributed Bellman-Ford algorithm.

  When a link fails and the topology changes, routers at both ends of the link detect changes in the distance vector table. Since the asynchronous distributed Bellman-Ford algorithm fits in the shortest path with an arbitrary initial value, the shortest path corresponding to a change in topology can be found. That is, when the distance vector table changes, each router updates the distance vector table according to the asynchronous distributed Bellman-Ford algorithm, and eventually converges to the distance vector table corresponding to the new topology. The advantage of the distance vector type is that each router can operate asynchronously and asynchronously, and only the connection relationship with neighboring routers needs to be recognized in addition to the distance vector table, so the amount of data held by each router is small. That's it.

  FIG. 12 shows a conventional method for selecting a distance vector. The procedure for selecting a conventional distance vector is as follows.

Step 1: Node X receives a new distance vector of destination node A from node Y.
Step 2: Is there a distance vector of the destination node A held by the node X and the next hop information is the node Y? If yes, go to Step5. If NO, go to Step3. In the case of YES, if there is a distance vector of the same next hop information at the same destination, it is considered that the distance has been updated.
Step 3: Is the distance information of the new distance vector shorter than the distance vector of the destination node A held by the node X? If yes, go to Step4. If NO, go to Step5.
Step 4: Update the distance vector of the destination node A.
Step 5: The distance vector of the destination node A is not updated.

  FIG. 13 shows the configuration of a conventional route control device. The path control device includes a distance vector reception unit 11 that receives distance vector information notified from an adjacent node, a distance vector comparison unit 12 that compares the received distance vector information with the contents of the distance vector table 3, and distance vector information. The distance vector table 13 in which the distance vector information is recorded, the distance vector update unit 15 that updates the distance vector table 13 based on the received distance vector information, the distance vector transmission unit 14 for notifying the adjacent nodes of the distance vector information, and the path And a switch unit 16 that performs switching.

  Up to this point, the description has been limited to an IP router that processes a node for each packet, but it can also be considered as a wavelength path switch that processes a node for each wavelength. A wavelength path network has a concept of a path. Setting a path means setting a wavelength corresponding to the path for each link. When data is transferred on the path, the wavelength is set to link-by-link and the wavelength is relayed.

  Consider that the distance vector type path control described above is applied when setting the wavelength path. The source node sends a signaling PATH message to the next hop toward the destination node. Here, a description will be given based on RSVP extended signaling. When sending the PATH message to the next hop, the distance vector table of FIG. 9 is used. Also in the next hop node, it is sent to the next hop using the distance vector table.

  By repeating this operation, the PATH message arrives at the destination node. The path of the PATH message sent from the source node to the destination node becomes the path of the wavelength path. When the signaling message arrives at the destination node, the destination node sends the RESV message in the reverse direction along the same path as that of the PATH message. When receiving the RESV message, the relay node sets the connection between the input port and the output port of the wavelength path switch. Which wavelength is used is loaded with a label in the RESV message.

  The label is a value assigned to each fiber link, and the label corresponds to the wavelength. The label value is defined for each link. Even if the red wavelength label value 100 is defined in one link, the red wavelength is the label value 200 in another link. This is because a label and a wavelength correspond to each link.

  If the relay node does not have a wavelength conversion function, the wavelengths must be continuous in the wavelength path to be set. When the relay node transfers the RESV message, it is necessary to select a label so that the wavelengths are continuous on both links on the wavelength path. Due to restrictions on wavelength continuity, there are restrictions on labels that can be used in the wavelength path.

Even if the relay node has a wavelength conversion function, if there is a wavelength conversion restriction, the wavelength conversion restriction condition must be satisfied in the wavelength path to be set. When the relay node transfers the RESV message, the relay node needs to select a label so as to satisfy the wavelength conversion restriction condition on both links on the wavelength path. Due to restrictions on wavelength conversion, there are restrictions on labels that can be used in the wavelength path.
NTT R & D Vol.52, No.3, p.182 (2003) "Photonic Network Traffic Control Technology (Akira Okamoto, Naoaki Yamanaka)"

  In the prior art, the distance vector has next hop information and distance information. The node propagates the distance vector to the adjacent node based on the distance vector, and the adjacent node updates the distance vector as necessary. However, the wavelength that can be used in the wavelength path network is limited. It is not clear from the distance vector table alone whether the wavelength that can be used in the link to the next hop satisfies the wavelength constraint condition from the source node to the destination node. Therefore, there is a problem that the route based on the distance vector table does not satisfy the wavelength constraint condition.

  The present invention has been made in such a background, and a route capable of providing a wavelength path route in an autonomous and distributed manner by creating a distance vector table while satisfying the wavelength constraint condition. An object is to provide a control device.

  In the prior art, the distance vector has next hop information and distance information. In determining the next hop route to the destination node, the constraint condition of wavelength conversion is not taken into consideration.

  In the present invention, the distance vector has next hop information, distance information, and label set information. The label set information carries a usable label. When propagating the distance vector to an adjacent node, label set information is created so that the label corresponding to the wavelength satisfies the constraint condition for wavelength conversion.

  A node that has received a distance vector does not update the distance vector even if the distance information is short, when usable label information is not in the distance vector. In addition, if the number of usable label information is smaller than the threshold, the node that has received the distance vector does not update the distance vector even if the distance information is short. When the number of usable label information satisfies the threshold value and the distance information is short, the distance vector is updated. However, if there is no distance vector corresponding to the destination node, the distance vector is updated if the number of usable label information is one or more.

  That is, according to the first aspect of the present invention, the next hop information corresponding to the destination, the distance information to the next hop, and the next next are provided respectively in the nodes of the network configured by connecting a plurality of nodes to each other. For each destination that can be used by the adjacent node when the node receives data from the adjacent node for the node adjacent to the own node, with a distance vector table that records the label information that can be used in the path to the hop A means for notifying distance vector information including label set information created based on the label conversion constraints and a label for each destination that can be used by the node when sending data to the adjacent node Means for receiving notification of distance vector information including set information from the adjacent node, and receiving this A path control device which is characterized in that a means for updating the distance vector table of the node based on the distance vector information received by the step (claim 1).

  Further, the means for notifying can comprise means for notifying the distance information included in the distance vector information as infinite when label set information satisfying the constraint condition for label conversion cannot be created. Item 2).

  Further, the updating means includes means for prohibiting updating of the distance vector table of the own node by the distance vector information when the distance vector information received by the receiving means does not include label information. (Claim 3).

  The updating means includes one or more label information in the distance vector information received by the receiving means, and distance information included in the distance vector information is recorded in the distance vector table of the own node. If the distance information is shorter than the distance information for the same destination, it is possible to provide means for updating the distance vector table of the own node with the distance vector information.

  Alternatively, the updating means prohibits updating of the distance vector table of the own node by the distance vector information when the distance vector information received by the receiving means does not include a number of label information equal to or greater than a threshold value. Means may be provided (claim 5).

  Alternatively, the updating means includes that the distance vector information received by the receiving means includes a number of label information equal to or greater than a threshold value, and the distance information included in the distance vector information is recorded in the distance vector table of the own node. In the case where the distance information is shorter than the distance information for the same destination, a means for updating the distance vector table of the own node with the distance vector information can be provided.

  According to a second aspect of the present invention, when installed in an information processing apparatus, the information processing apparatus is provided in each of the nodes of a network configured by connecting a plurality of nodes to each other, and corresponds to a destination. A function corresponding to the distance vector table in which the hop information, the distance information to the next hop, and the label information that can be used in the path to the next hop are recorded, and the node adjacent to the node is adjacent to the node. When receiving data from a node, the function that notifies the distance vector information including the label set information created based on the label conversion constraint condition for each destination that can be used by the adjacent node, and the own node to the adjacent node Distance vector containing label set information for each destination that can be used by the node when sending data -Realizing a function corresponding to a path control device having a function of receiving notification of information from the adjacent node and a function of updating the distance vector table of the own node based on the distance vector information received by the receiving function. (Claim 7).

  In addition, as the function to be notified, when label set information that satisfies the constraint conditions for label conversion cannot be created, it is possible to realize a function to notify distance information included in the distance vector information as infinite ( Claim 8).

  Further, as the function to be updated, when the distance vector information received by the receiving function does not include label information, a function for prohibiting the updating of the distance vector table of the own node by the distance vector information is realized. (Claim 9).

  Further, as the function to be updated, one or more label information is included in the distance vector information received by the receiving function, and the distance information included in the distance vector information is recorded in the distance vector table of the own node. If the distance information is shorter than the distance information for the same destination, the function of updating the distance vector table of the own node can be realized by the distance vector information.

  Alternatively, as the function to be updated, when the distance vector information received by the receiving function does not include a number of label information equal to or greater than a threshold value, the updating of the distance vector table of the own node by the distance vector information is prohibited. The function can be realized (claim 11).

  Alternatively, as the updating function, the distance vector information received by the receiving function includes a number of label information equal to or greater than a threshold value, and the distance information included in the distance vector information is recorded in the distance vector table of the own node. When the distance information is shorter than the distance information for the same destination, a function of updating the distance vector table of the own node with the distance vector information can be realized (claim 12).

  A third aspect of the present invention is a recording medium readable by the information processing apparatus on which the program of the present invention is recorded (claim 13). 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 directly installed in the information processing apparatus via a network from a server holding the program of the present invention.

  As a result, a general-purpose information processing device is used to create a distance vector table while satisfying the wavelength constraint conditions, and realize a path control device that can provide wavelength path routes in an autonomous and distributed manner. be able to.

  According to the present invention, the wavelength path network and the TDM network have restrictions on the wavelengths or time slots that can be used, and only when the constraint conditions for label conversion corresponding to the wavelengths or time slots are satisfied, are stored in the distance vector table. Since the distance vector is updated, the path based on the distance vector table satisfies the constraint condition of label conversion. Further, when the wavelength satisfying the constraint condition for label conversion is smaller than the threshold, the route is excluded, so that the label resource can be used effectively.

  The configuration of the route control apparatus according to the embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram of a path control apparatus according to this embodiment.

  As shown in FIG. 7, the present embodiment is provided in each of the nodes of a network configured by connecting a plurality of nodes to each other. As shown in FIG. 1, the next hop information corresponding to the destination and the next hop information are provided. When the distance information to the hop and the distance vector table 3 in which the label information that can be used in the path to the next hop is recorded are provided to the node adjacent to the own node, when the own node receives data from the adjacent node A distance vector transmission unit 4 for notifying distance vector information including label set information created based on a conversion constraint managed by the label management unit 6 for a set of labels for each destination that can be used by the adjacent node; Distortor that includes label set information for each destination that can be used by the node when sending data to the adjacent node A distance vector receiving unit 1 for receiving notification of distance vector information from the adjacent node, and a distance vector updating unit 5 for updating the distance vector table 3 of the own node based on the distance vector information received by the distance vector receiving unit 1 A route control device characterized in that (Claim 1).

  The distance vector transmission unit 4 includes means for notifying that the distance information included in the distance vector information is infinite when label set information that satisfies the constraint conditions for label conversion cannot be created (Claim 2).

  In the first embodiment, the distance vector update unit 5 includes the distance vector information received by the distance vector reception unit 1 in the distance vector table of its own node based on the distance vector information when the distance vector information does not include label information. Means for prohibiting updating is provided.

  Furthermore, in the first embodiment, the distance vector update unit 5 includes one or more pieces of label information in the distance vector information received by the distance vector receiving unit 1, and the distance information included in the distance vector information is automatically stored. If the distance information for the same destination recorded in the distance vector table 3 of the node is shorter than the distance information, a means for updating the distance vector table 3 of the own node with the distance vector information is provided.

  Further, in the second embodiment, the distance vector update unit 5 determines that the distance vector information received by the distance vector receiving unit 1 includes the number of pieces of label information equal to or greater than the threshold in the own node of the distance vector information. Means for prohibiting updating of the distance vector table 3 is provided.

  In the second embodiment, the distance vector updating unit 5 includes the distance vector information received by the distance vector receiving unit 1 including a number of label information equal to or greater than a threshold value, and the distance information included in the distance vector information. When the distance information for the same destination recorded in the distance vector table 3 of the own node is shorter than the distance information, a means for updating the distance vector table 3 of the own node with the distance vector information is provided.

  The present invention can be implemented as a program that, when installed in a general-purpose information processing apparatus, causes the information processing apparatus to realize a function corresponding to the path control apparatus of the present invention (claims 7 to 12). The program is recorded on a recording medium and installed in the information processing apparatus (Claim 13), or installed in the information processing apparatus via a communication line, so that the distance vector receiving unit 1, distance is installed in the information processing apparatus. Functions corresponding to the vector comparison unit 2, the distance vector table 3, the distance vector transmission unit 4, the distance vector update unit 5, and the label management unit 6 can be realized.

  Hereinafter, this embodiment will be described in more detail.

(First Example)
FIG. 2 shows the distance vector table 3 of the first embodiment. Compared with the prior art, label set information is newly added. Labels corresponding to usable wavelengths are mounted on the label set information. The label is a value assigned to each fiber link, and the label corresponds to the wavelength. The label value is defined for each link.

  Even if 100 is defined as the label value of the red wavelength in one link, the label value of the red wavelength is 200 in another link. This is because a label and a wavelength correspond to each link. In the example of FIG. 2, when 129.60.225.0/24 is the destination, the next hop is the node E, and the usable labels up to the node E are 100, 110, and 140. I mean. Moreover, the distance to 129.60.225.0/24 means that it is 3.

  FIG. 3 shows a conceptual diagram of the distance vector type operation of the first embodiment. Node B creates label set information of the distance vector of destination node A for node X. When considering the label set of the distance vector of the destination node A that is the source node of the node B and the label value that can be used between the link BX and the wavelength constraint conditions, the node B considers the destination node A for the node X that satisfies these conditions. The distance vector label set information is not found.

  Therefore, it can be seen that there is no route from node X satisfying the wavelength constraint condition to node A via node B. Therefore, the node B propagates to the distance vector of the destination node A to the node X with the distance set to infinity and no label information. Here, infinite is actually a sufficiently large value, and this value is infinite.

  On the other hand, as shown in FIG. 4, the node C holds the next hop information as the node D, the distance information as 100, and the label set information as the labels 101, 120, and 150 as the distance vector of the destination node A. FIG. 4 is a diagram illustrating a state of propagation of label set information according to the present embodiment. The label 115 is excluded from the label set information because the wavelength constraint condition is not satisfied. The relationship between the label and the wavelength is as shown in FIG. When node C propagates the distance vector to node X, label set information for node X is created. The usable labels of the link XC are 201, 215, and 250. Here, it is assumed that the node C has no wavelength conversion function. The label set information of destination node A held by node C is {101, 120, 150}, and node C does not have a wavelength conversion function, so node C propagates a distance vector to node X. The label set information to be performed is only {201, 250}. Since the label 215 has no wavelength conversion function, it is excluded from the label set. Accordingly, the distance vector of the destination node A is as shown in FIG.

  In FIG. 3, the node X receives the distance vector of the destination node A from the node B and the node C. In this case, the distance vector of the node C as the next hop is selected. At this time, the distance of the distance vector is set to 101 by calculating the sum of the distance 100 and the distance 1 of the link XC.

  FIG. 5 shows the distance vector selection method of the first embodiment. The procedure of the distance vector selection method of the first embodiment is as follows.

Step 1: Node X receives a new distance vector of destination node A from node Y.
Step 2: Is there a distance vector of the destination node A held by the node X and the next hop information is the node Y? If yes, go to Step5. If NO, go to Step3. In the case of YES, if there is a distance vector of the same next hop information at the same destination, it is considered that the distance information has been updated.
Step 3: Is there at least one label information in the label set information? If yes, go to Step4. If NO, go to Step 6.
Step 4: Is the distance information of the new distance vector shorter than the distance vector of the destination node A held by the node X? If yes, go to Step5. If NO, go to Step 6.
Step 5: Update the distance vector of the destination node A.
Step 6: The distance vector of the destination node A is not updated.

  FIG. 1 shows the configuration of the path control apparatus of the first embodiment. The difference from FIG. 13 is that the distance vector includes label set information in the present invention, the distance vector receiving unit 1, the distance vector comparing unit 2, the distance vector table 3, the distance vector updating unit 5, and the distance vector transmitting unit. 4 has a function of processing label set information in accordance with the procedure described above. The processing of the actual correspondence between the wavelength and the label and the constraint condition of the wavelength conversion function is performed by the label management unit 6 when creating the label set information.

  In this way, the wavelength path network has restrictions on the wavelengths that can be used, and the distance vector is updated in the distance vector table 3 only when the wavelength restriction condition is satisfied. Therefore, the route based on the distance vector table 3 Satisfies the wavelength constraint condition.

(Second embodiment)
FIG. 6 shows a method for selecting a distance vector according to the second embodiment. The procedure of the distance vector selection method of the second embodiment is as follows.

Step 1: Node X receives a new distance vector of destination node A from node Y.
Step 2: Is there a distance vector of the destination node A held by the node X and the next hop information is the node Y? If YES, go to Step 6. If NO, go to Step3. In the case of YES, if there is a distance vector of the same next hop at the same destination, it is considered that the distance has been updated.
Step 3: Does the distance vector of the destination node A held by the node X not exist, and is there one or more label information in the label set information? If yes, go to Step3. If NO, go to Step4.
Step 4: Is the number of label information included in the label set information of the new distance vector greater than or equal to the threshold value? If yes, go to Step5. If NO, go to Step7.

Step 5: Is the distance information of the new distance vector shorter than the distance vector of the destination node A held by the node X? If YES, go to Step 6. If NO, go to Step7.
Step 6: Update the distance vector of the destination node A.
Step 7: The distance vector of the destination node A is not updated.

  In the second embodiment, a threshold is set for the number of label information included in the label set information of the new distance vector, and the distance vector of the label set having the number of label information smaller than the threshold is adopted as the distance vector regardless of the distance information. do not do. This means that when the number of label information is small, the usable wavelength is small. If there is another candidate distance vector with a large number of label information, it is adopted even if the distance information is large. Thereby, wavelength resources can be used effectively.

(Third embodiment)
In the first and second embodiments, the wavelength path network has been described. In the third embodiment, the present invention can also be applied to a TDM network. In the wavelength path network, the label corresponds to the wavelength. In a TDM network, a label corresponds to a time slot. If the node is a TDM switch that processes every time slot, it is a TDM network.

  Examples of the TDM network include an SDH network and a SONET network. A TDM network has a concept of a path. Setting a path means setting a time slot corresponding to the path for each link. When data is transferred on the path, the time slot is set to link-by-link, and the time slot is relayed.

  The wavelength conversion constraint described in the first and second embodiments can be handled by replacing the wavelength with a time slot as in the third embodiment, such as the time slot conversion constraint. If such a constraint condition is expressed more generally, it can be expressed as a constraint condition for label conversion.

  According to the present invention, the distance vector table can be created while satisfying the wavelength constraint condition, and the wavelength path route can be provided autonomously and distributedly, so that the operation efficiency of the network can be improved. Therefore, it is possible to construct a network that is highly convenient for network operators and network users.

The block block diagram of the route control apparatus of a present Example. The figure which shows the example of the distance vector table | surface of a present Example. The conceptual diagram of the operation | movement of the distance vector type | mold of a present Example. The figure which shows the condition of propagation of the label set of a present Example. The flowchart which shows the selection procedure of the distance vector of 1st Example. The flowchart which shows the selection procedure of the distance vector of 2nd Example. Conceptual diagram of network. The figure which shows the classification | category of IP routing, and an operation principle. The figure which shows the example of the conventional distance vector table | surface. The conceptual diagram of operation | movement of the conventional distance vector type | mold. The figure for demonstrating Bellman's formula. The flowchart which shows the selection procedure of the conventional distance vector. The block block diagram of the conventional route control apparatus.

Explanation of symbols

1, 11 Distance Vector Receiving Unit 2, 12 Distance Vector Comparison Unit 2, 13 Distance Vector Table 4, 14 Distance Vector Transmitting Unit 5, 15 Distance Vector Updating Unit 6, Label Management Unit 7, 16 Switch Unit

Claims (13)

A plurality of nodes are respectively provided in the nodes of the network configured to be connected to each other,
A distance vector table in which the next hop information corresponding to the destination, the distance information to the next hop, and the label information usable in the path to the next hop are recorded;
A distance that includes label set information created for a node adjacent to its own node based on the label conversion restriction conditions for each destination that can be used by the adjacent node when the node receives data from the adjacent node A means of notifying vector information;
Means for receiving, from the adjacent node, notification of distance vector information including label set information for each destination that can be used by the local node when the local node transmits data to the adjacent node;
And a means for updating the distance vector table of the own node based on the distance vector information received by the receiving means.   The route according to claim 1, wherein the notifying means includes means for notifying the distance information included in the distance vector information as infinite when label set information satisfying the constraint condition of label conversion cannot be created. Control device.   2. The updating means comprises means for prohibiting updating of the distance vector table of the own node by the distance vector information when label information is not included in the distance vector information received by the receiving means. The described route control device.   In the updating means, the distance vector information received by the receiving means includes one or more label information, and the distance information included in the distance vector information is recorded in the distance vector table of the own node. 2. The route control device according to claim 1, further comprising means for updating the distance vector table of the own node with the distance vector information when the distance information is shorter than the distance information for the destination.   The updating means includes means for prohibiting updating of the distance vector table of the own node by the distance vector information when the distance vector information received by the receiving means does not include a number of label information equal to or greater than a threshold value. The route control device according to claim 1, further comprising:   In the updating means, the distance vector information received by the receiving means includes a number of label information equal to or greater than a threshold value, and the distance information included in the distance vector information is recorded in the distance vector table of the own node. 2. The route control apparatus according to claim 1, further comprising means for updating the distance vector table of the own node with the distance vector information when the distance information is shorter than the distance information for the same destination. By installing on an information processing device,
A plurality of nodes are respectively provided in the nodes of the network configured to be connected to each other,
A function corresponding to the distance vector table in which the next hop information corresponding to the destination, the distance information to the next hop, and the label information usable in the path to the next hop are recorded;
A distance that includes label set information created for a node adjacent to its own node based on the label conversion restriction conditions for each destination that can be used by the adjacent node when the node receives data from the adjacent node A function to notify vector information,
A function of receiving, from the adjacent node, notification of distance vector information including label set information for each destination that can be used by the local node when the local node transmits data to the adjacent node;
A program for realizing a function corresponding to a path control device having a function of updating the distance vector table of its own node based on the distance vector information received by the receiving function.   8. The program according to claim 7, wherein, as the function to be notified, when the label set information satisfying the constraint condition of label conversion cannot be created, the function of notifying distance information included in the distance vector information as infinity is realized. .   8. The function of updating, when the distance vector information received by the receiving function includes no label information, implements a function of prohibiting updating of the distance vector table of the own node by the distance vector information. The program described.   As the updating function, the distance vector information received by the receiving function includes one or more label information, and the distance information included in the distance vector information is recorded in the distance vector table of the own node. 8. The program according to claim 7, wherein a function for updating the distance vector table of the own node is realized by the distance vector information when the distance information is shorter than the distance information for the destination.   As a function of updating, when the distance vector information received by the receiving function does not include a number of label information equal to or greater than a threshold value, a function of prohibiting updating of the distance vector table of the own node by the distance vector information The program according to claim 7 to be realized.   As the function to be updated, the distance vector information received by the receiving function includes a number of label information equal to or greater than a threshold value, and the distance information included in the distance vector information is recorded in the distance vector table of the own node. 8. The program according to claim 7, wherein when the distance information is shorter than the distance information for the same destination, a function for updating the distance vector table of the own node with the distance vector information is realized.   13. A recording medium readable by the information processing apparatus, on which the program according to claim 7 is recorded.

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