JP2007228087A - Path setting system and path setting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology capable of utilizing an efficient path for path routing in a path setting bridged over a plurality of domains. <P>SOLUTION: A path setting system establishes a path 5 from a start point domain 1a to which a start point node 3a acting like the start point of the path 5 belongs up to an end point domain 1c to which an end point node 1c to which an end point node 3i acting like the and point of the path 5 belongs, the routing computation unit 2 of each domain 1 includes a routing computation means 34 for computing the result of routing computation of the path 5 of its own domain 1 referring to the network configuration of its own domain 1 and a routing concealing means 40 for making the node 3 of its own domain 1 utilize the result of the routing computation and concealing the result of the routing computation from node 3 of the other domains 1, and each node 3 of each domain 1 includes a path setting means for setting the path 5 on the basis of the result of the routing computation concealed for the nodes 3 of the other domains 1 by the routing concealing means 40. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a path setting system and a path setting method.

  The network system includes nodes and links. A node is a communication device having an exchange function. A link is a communication line that connects nodes and serves as an information transfer medium.

  A domain is a logical network unit that groups nodes together. The network system may be composed of one domain or may be composed of a plurality of domains. Links are classified as intra-domain links or inter-domain links. An intra-domain link is a link when two nodes to which the link connects belong to the same domain. An inter-domain link is a link when two nodes to which the link connects belong to different domains.

  The route calculation device belongs to one domain and performs route calculation within the domain (own domain) to which it belongs. In order to perform route calculation, the route calculation device grasps network information inside the domain, link information between domains, and arrival information to each node and link.

  A path is a communication path set between two nodes via a plurality of links. The path is set in the section from the start point to the end point. The start point node is a device that becomes the start point of the path, and the end point node is a device that becomes the end point of the path. The start point domain is a domain to which the start point node belongs, the end point domain is a domain to which the end point node belongs, and the relay domain is a domain located at a relay point from the start point domain to the end point domain. The start point route calculation device belongs to the start point domain, the relay route calculation device belongs to the relay domain, and the end point route calculation device belongs to the end point domain. A path that spans multiple domains is a path in which the start domain and the end domain are different domains.

  When setting up a path that spans multiple domains, there is a method to set up a path by calculating a path by providing a path calculation device for each domain and communicating between the node, the route calculation device, and the route calculation device. Yes (Non-Patent Documents 1 and 2). In addition, there is a communication protocol between the node and the route calculation device and the route calculation device at this time (Non-Patent Document 3).

  It is not recommended from the viewpoint of security to notify other domains (domains different from the own domain) of detailed information about the own domain because it may give a clue to unauthorized access. On the other hand, in the path setting across a plurality of domains, it is necessary to perform a cooperative operation between the own domain and another domain, and information regarding the other domain is required. Therefore, in the methods described in Non-Patent Documents 1 to 3, detailed information about the own domain is concealed from the other domain by not notifying part of the information about the own domain to the other domain.

  Specifically, the information concealment notifies the other domain of the inter-domain link between the own domain and the other domain, but does not notify the intra-domain link of the own domain to the other domain. As a result, the self domain grasps the list of domains that are passed from the start point to the end point, but does not grasp the internal route information (intra-domain links of other domains) when the route domain is another domain.

In addition, the link information to be routed is specified when setting the path. At this time, the nodes belonging to the own domain are not concealed in the intra-domain link of the own domain and the inter-domain link of the own domain or other domains. So it can be specified as a route. However, intra-domain links of other domains are hidden and cannot be specified.
IETF, “Path Computation Element (PCE) Architecture”, [online], [searched on December 1, 2005], Internet <URL: http://www.ietf.org/internet-drafts/draft-ietf-pce -architecture-03.txt>, chapter 4.2, chapter 5.4, chapter 5.6 Vasseur, “Path Computation Element (PCE) models Architecture and Applications”, MPLS 2005, October 2005 IETF, “Path Computation Element (PCE) communication Protocol (PCEP) -Version 1-”, [online], [Searched on December 1, 2005], Internet <URL: http://www.ietf.org/internet -drafts / draft-ietf-pce-pcep-00.txt>

  In the conventional concealment of information described above, the route calculated by the route computation device is deleted as the information to be concealed, and thus has not been utilized in path setting. Therefore, the node that sets the path (the node that becomes the end point of the inter-domain link) calculates the path of the path itself, not the path calculation device. As a result, there is a possibility that the node that performs the path setting calculates a route different from the route calculated in advance by the route calculation device.

  Usually, a route calculation device is a device that calculates a route based on detailed information of its own domain, and therefore, an efficient route (having a wider bandwidth) than a route calculated by a node that performs path setting that is part of its own domain. Route, route with few hops, etc.). However, since the route used for path setting is a route calculated by the node, an inefficient route may be selected.

  In view of the above, the main object of the present invention is to solve the problems described above and to use an efficient route as a path route in path setting across a plurality of domains.

  In order to solve the above problems, the present invention provides a network system in which a start point domain to which a start point node that is a start point of a path belongs and a destination domain to which an end point node that is an end point of a path belongs are different domains. A path setting system for setting a path based on a route calculation result calculated by a calculation device, wherein the route calculation device of each domain refers to a network configuration of the own domain and calculates the route of the path of the own domain. A route calculation means for calculating a result; and a route concealment means for concealing a result of the route calculation from a node of the own domain and concealing it from a node of another domain. A path is set based on the route calculation result concealed in the node of the other domain by concealment means. Characterized in that it has a scan setting means.

  As a result, since the route calculation result calculated by the route calculation device is used, an efficient route can be used as the route of the path in the path setting across a plurality of domains. In addition, since the node does not need to perform route calculation by itself, the path setup time can be shortened.

  In the present invention, the route concealment unit includes an encryption unit that encrypts the route calculation result, and the path setting unit decrypts the route calculation result of the own domain encrypted by the encryption unit. It has the decoding means to perform.

  Thereby, the concealed information is not continuously stored in the storage means.

  In the present invention, the route concealing unit includes a path storage unit that stores the route calculation result in a storage unit, and the path setting unit stores the route calculation result stored in the path storage unit in the route calculation device. It is characterized by having a route inquiry means to acquire by making an inquiry to.

  As a result, it is not necessary to include information to be concealed in the path setting message, so that the implementation becomes easy.

  In the present invention, the path concealing means has path setting instruction means for causing the node to set a preset path that is a part of a path based on the path calculation result, and the path setting The means has path setting instruction processing means for setting a preset path in accordance with an instruction from the path setting instruction means, and sets the path based on the preset path.

  Thereby, the preset time is set in advance, so that the time for setting the path can be shortened. Further, it is possible to prevent a situation in which a resource on a route calculated at the time of path calculation is lost at the time of path setting and the path setting is not established.

  The present invention is characterized in that the path setting instruction processing means sets a timer for the set preset path and deletes the preset path that is not used after a predetermined time has elapsed.

  As a result, unnecessary preset paths are deleted without an explicit instruction from the administrator, so that highly efficient path management can be realized.

  The present invention is characterized in that a plurality of paths set from the start node to the end node are set as redundant paths that do not share the nodes relaying each other.

  As a result, when one of the paths constituting the redundant path becomes unable to communicate, it can be switched to the other path, so that a highly reliable network can be constructed.

  The present invention is characterized in that the route calculation device and the node belonging to the same domain are configured as a single casing.

  Thereby, since the number of components of the network system can be reduced, the introduction cost can be suppressed.

  The present invention provides a route calculation result calculated by a route calculation device of each domain in a network system in which a start point domain to which a start point node to be a path start point belongs and a destination domain to which an end point node to be a path end point belongs are different domains A path setting method for setting a path based on the path, wherein the route calculation device of each domain calculates the route calculation result of the path of the own domain by referring to the network configuration of the own domain and stores it in the storage means A procedure of storing and a procedure of causing the node of the own domain to use the route calculation result and concealing it from a node of another domain, and the node of each domain is executed by the route calculation device by the other domain Executing a procedure for setting a path based on the route calculation result concealed in the node. That.

  As a result, since the route calculation result calculated by the route calculation device is used, an efficient route can be used as the route of the path in the path setting across a plurality of domains. In addition, since the node does not need to perform route calculation by itself, the path setup time can be shortened.

  According to the present invention, since the route calculation result calculated by the route calculation device is used, an efficient route can be used as a path route in path setting across a plurality of domains. In addition, since the node does not need to perform route calculation by itself, the path setup time can be shortened.

  FIG. 1 is a configuration diagram showing a path setting system common to the embodiments of the present invention.

  The path setting system includes three domains 1 (domain 1a, domain 1b, and domain 1c). Domain 1 is composed of a set of nodes 3. For example, the domain 1a includes two nodes 3 (node 3a and node 3b). Domain 1 has a link 4. For example, the domain 1a has an intra-domain link 4 (link 4a) and an inter-domain link 4 (link 4b, link 4c).

  The domain 1 has a route calculation device 2. For example, the route calculation device 2a of the domain 1a calculates a route inside the domain 1a. The route calculation device 2a grasps the link information (link 4a, link 4b, link 4c), and reaches the link 4d to the link 4k and further reaches the node 3c to the node 3i via the relay domain 1b. I know what to do.

  Note that the devices (node 3 and route calculation device 2) of the present embodiment are configured as computers each including at least a memory serving as a storage unit used when performing arithmetic processing and an arithmetic processing device that performs the arithmetic processing. The The memory is constituted by a RAM (Random Access Memory) or the like. Arithmetic processing is realized by an arithmetic processing unit configured by a CPU (Central Processing Unit) executing a program on a memory. In addition to the apparatus, the present embodiment includes a program for causing the apparatus to execute arithmetic processing, and a computer-readable recording medium on which the program is recorded.

  The path 5a is a path 5 across a plurality of domains 1 in the path setting system. The path 5a is set from the start point node 3a to the end point node 3i by the path <link 4a → link 4c → link 4f → link 4j → link 4k>.

  Each node 3 can grasp a link 4 belonging to a domain to which the node 3 belongs and a link 4 between domains including different domains 1 as paths of the path 5. Each node 3 cannot grasp the link 4 belonging to other than the domain to which the node 3 belongs. Only the link 4 that can also grasp the path of the path DB 18 is stored. Further, only the link 4 that can be similarly grasped as the route information included in the path setting request information.

  For example, in FIG. 1, the start node 3a can grasp <link 4a → link 4c → link 4j> as the path 5 but cannot grasp other links 4. That is, when attention is paid to the start point domain 1a to which the start point node 3a belongs, the intra-domain link 4 (link 4a) and the inter-domain link 4 (link 4c, link 4j) of the start point domain 1a can be grasped.

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 to 5. The first embodiment is characterized in that the node 3 of the own domain 1 decrypts the encrypted route calculation result as a method of acquiring the route calculation result of the route calculation device 2 of the own domain 1.

  FIG. 2 is a configuration diagram showing the node 3. The node 3 includes a path setting unit 12, a route calculation request unit 14, a decryption unit 16, and a path DB 18.

  The path setting unit 12 sets the path 5 by exchanging path setting request information and path setting response information with the adjacent node 3. Information on the set path 5 is stored in the path DB 18. The path setting means 12 corresponds to, for example, that specified by RFC3473 (Generalized Multi-Protocol Label Switching (GMPLS) Signaling Resource ReserVation Protocol-Traffic Engineering (RSVP-TE) Extensions). Note that the node 3 to which the path setting unit 12 should transmit the path setting request information is stored in the path information of the path DB 18, but the DB for indicating through which link 4 the node 3 is connected. It doesn't matter if it is different.

  The route calculation requesting unit 14 generates route calculation request information including the start point node ID, the end point node ID, and the bandwidth, and transmits the route calculation request information to the route calculation device 2. Receive. The route calculation device 2 that is the inquiry destination is set in advance, for example.

  The decrypting means 16 performs decryption when the path included in the path setting request information is encrypted.

  The path DB 18 stores information on the path 5. The starting point node ID is an identifier that uniquely indicates the device that is the starting point of the path 5. The end node ID is an identifier that uniquely indicates the device that is the end point of the path 5. The path identifier is an identifier that uniquely indicates the path 5 for the pair of the start node 3a and the end node 3i, for example. The route is information indicating a list of links 4 through which the path 5 passes. The bandwidth is information indicating the bandwidth of the path 5.

  FIG. 3 is a configuration diagram showing the route calculation device 2. The route calculation device 2 includes a route calculation request processing means 32, a route calculation means 34, a route calculation request means 36, an encryption means 38, a route concealment means 40, a link DB 42, and a reachability DB 44.

  The route calculation request processing means 32 receives route calculation request information from the node 3 or other route calculation means 34, and sends route calculation response information for returning a route calculation result to the node 3 or other route calculation means 34. Send. Further, by searching the reachability DB 44, whether or not the node 3 indicating the end node ID included in the route calculation request information is in the domain to which the route calculation device 2 belongs, and the node 3 indicating the start node ID is determined. It is determined whether or not the route calculation apparatus 2 is in the domain to which it belongs. If it is not in the domain to which the route calculation device 2 belongs, domain information to which the node 3 belongs is acquired.

  Based on the reachability DB 44 and the path setting request information, the route calculation request unit 36 transmits the route calculation request information to the other route calculation device 2 and returns the route calculation result from the other route calculation device 2. Receives route calculation response information. The route calculation response information is composed of concealment information including the cost of the route.

  For example, in FIG. 1, when the start point route calculation device 2a receives the route calculation request information of the end point node 3i, the reachability DB 44 determines that it should pass through the relay domain 1b, and the relay route calculation device of the relay domain 1b. The route calculation request information is transmitted to 2b. Information on the route calculation device 2 of the other domain 1 to which information is to be transmitted is set in advance, for example.

  The route calculation means 34 calculates the route of the path 5 based on the route calculation request information, the route calculation response information, and the link DB 42. As a path calculation method, path calculation is performed by a known restricted Dijkstra method or the like. The route calculation means 34 performs route calculation in each of the following four cases.

  In case 1, the route calculation request processing means 32 determines that the node 3 indicated by the end node ID included in the route calculation request information is in the domain to which the route calculation device 2 belongs, and is included in the route calculation request information. This is a case where it is determined that the node 3 indicated by the starting point node ID is in the domain to which the route calculation device 2 belongs. In this case 1, the route calculation means 34 uses the path DB 18 to perform route calculation from the start point node 3a to the end point node 3i.

  In case 2 (end point route calculation device 2c), the route calculation request processing means 32 determines that the node 3 indicated by the end point node ID included in the route calculation request information is in the domain to which the route calculation device 2 belongs, and This is a case where it is determined that the node 3 indicated by the start node ID included in the route calculation request information is not in the domain to which the route calculation device 2 belongs. In this case 2, the route calculation means 34 uses the link DB 42, the node 3 connected to the domain 1 to which the route calculation device 2 that transmitted the route calculation request information belongs, and the end point node included in the route calculation request information Route calculation between the nodes 3 indicated by the ID is performed. For example, in FIG. 1, the end point route calculation device 2c performs route calculation from the node 3h to the end point node 3i.

  In case 3 (relay route calculation device 2b), the route calculation request processing means 32 determines that the node 3 indicated by the end node ID included in the route calculation request information is not in the domain to which the route calculation device 2 belongs, and This is a case where it is determined that the node 3 indicated by the start node ID included in the route calculation request information is not in the domain to which the route calculation device 2 belongs. In this case 3, the route calculation means 34 connects to the domain 1 to which the route calculation device 2 that transmitted the route calculation request information belongs, using the cost to the end node 3i included in the route calculation response information and the link DB 42. The route calculation is performed between the node 3 to be executed and the node 3 indicated by the end point node ID included in the route calculation request information. For example, in FIG. 1, the relay route calculation device 2b performs route calculation of the end node 3i from the nodes 3d and 3c.

  In case 4 (start point route calculation device 2a), the route calculation request processing means 32 determines that the node 3 indicated by the end node ID included in the route calculation request information is not in the domain to which the route calculation device 2 belongs, and This is a case where it is determined that the node 3 indicated by the start node ID included in the route calculation request information is in the domain to which the route calculation device 2 belongs. In this case 4, the route calculation means 34 uses the cost to the end node 3i included in the route calculation response information and the link DB 42 to change from the node 3 indicated by the start node ID included in the route calculation request information to the end node. Route calculation between the nodes 3 indicated by 3i is performed. For example, in FIG. 1, the route calculation apparatus 1 performs route calculation from the node 3a to the end node 3i.

  The route concealment unit 40 conceals information inside the domain from the route computation device 2 belonging to another domain 1 by extracting only a part of the information from the route computation result. Specifically, the shortest cost to reach the end node 3i is calculated from the route calculation result via the link 4 connected to the node 3 belonging to the domain 1 to which the route calculation device 2 that transmitted the route calculation request information belongs. .

  For example, in the example of FIG. 1, the end point route calculation device 2c passes the link 4j to reach the end point node 3i (2 if the link cost is 1), and the link 4i. The cost to reach the end node 3i (2 if the link cost is 1) is calculated. This calculation result is transmitted to the relay route calculation device 2b by the route calculation request processing means 32.

  The encryption unit 38 conceals the information inside the domain from the route calculation device 2 belonging to the other domain 1 by encrypting the route information inside the domain in the route calculation result. Specifically, the encryption information of the route inside the domain is calculated. For example, in the example of FIG. 1, the end point route calculation device 2c calculates the encryption information of the route (link 4k). This calculation result is transmitted to the relay route calculation device 2b by the route calculation request processing means 32.

  The link DB 42 stores information on the link 4. The A-end node ID is an identifier that uniquely indicates a device that is one end of the link 4. The Z-end node ID is an identifier that uniquely indicates a device that is the other end of the link 4. The A-end IF-ID is an identifier that uniquely indicates the link 4 in the A-end device. The Z end IF-ID is an identifier that uniquely indicates the link 4 in the Z end device. The bandwidth is information indicating the maximum usable bandwidth of the link 4. The remaining bandwidth is information indicating the remaining bandwidth of the link 4. The domain ID is set when the link 4 connects the node 3 belonging to the domain 1 to which the route calculation device 2 belongs and the node 3 belonging to the different domain 1, and is information that uniquely identifies the different domain 1. Stored.

  For example, in the example of FIG. 1, the start point route calculation device 2 a stores the domain 3 i “relay domain 1 b” as the link information of the link c in the link DB 42. The information of the link DB 42 may be acquired by, for example, OSPF-TE (Traffic Engineering extension to Open Shortest Path First) defined in RFC3630.

  The reachability DB 44 stores information on reachable devices and links 4. That is, it indicates which domain 1 should be reached to reach each node 3 and link. The ID is an identifier that uniquely identifies the node 3 or the link 4. The domain ID is an identifier of domain 1 to be routed. As the domain ID stored in the reachability DB 44, the domain 1 adjacent to the domain 1 to which the route calculation device 2 belongs is specified.

  The information in the reachability DB 44 may be acquired by, for example, BGP (Border Gateway Protocol) defined in RFC1771. In this method, the priority for each domain 1 is used as a method of determining the reachable device and the domain 1 through which the link 4 should pass.

  FIG. 4 is a flowchart showing the path setting process. The route calculation result of path 5 is <link 4a → link 4c → link 4f → link 4j → link 4k>. Note that the information of the link 4f and the link 4k is encrypted.

  Hereinafter, the operation of route calculation will be described. The starting point node 3a transmits the route calculation request information to the route calculation device 2a of the own domain 1a by the route calculation requesting means 14, for example, triggered by an instruction from the operator (S1). The route calculation request information includes specific information (such as an address) of the start node 3a and the end node 3i.

  The route calculation device 2a uses the route calculation request processing means 32 to search the reachability DB 44 to determine whether or not the end node 3i of the received route calculation request information belongs to its own domain 1a. In this case, since the end node 3i does not belong to the own domain 1a, the route calculation process is performed to acquire the domain 1b to be passed (S2).

  The route calculation device 2a transmits the route calculation request information to the route calculation device 2b of the domain 1b to be routed by the route calculation request means 36 (S3).

  The route calculation device 2b uses the route calculation request processing means 32 to search the reachability DB 44 to determine whether or not the end node 3i of the received route calculation request information belongs to its own domain 1b. This time, since the end node 3i does not belong to the own domain 1b, the route calculation process is performed to acquire the domain 1c to be passed (S4).

  The route calculation device 2b transmits route calculation request information to the route calculation device 2c of the domain 1c to be routed by the route calculation request means 36 (S5).

  The route calculation device 2b uses the route calculation request processing means 32 to search the reachability DB 44 to determine whether or not the end node 3i of the received route calculation request information belongs to its own domain 1c. This time, the route calculation process is performed to the effect that the end node 3i belongs to the own domain 1c (S6).

  The route calculation device 2c performs route calculation by the route calculation means 34 (S7).

  The route calculation device 2c conceals the route calculation result by the route concealment means 40 (S8). In the route calculation device 2c, the route calculation request processing means 32 transmits the route calculation response information regarding the hidden route calculation result obtained in S8 to the route calculation device 2b that has transmitted the route calculation request information (S9). .

  When the route calculation requesting unit 36 receives the route calculation response information, the route calculating unit 2b performs route calculation (S10).

  The route calculation device 2b conceals the route calculation result by the route concealment means 40 (S11). In the route calculation device 2b, the route calculation request processing means 32 transmits route calculation response information related to the hidden route calculation result obtained in S11 to the route calculation device 2a that has transmitted the route calculation request information (S12). .

  When the route calculation requesting unit 36 receives the route calculation response information, the route calculating unit 2a performs route calculation (S13).

  In the route calculation device 2a, the route calculation request processing means 32 transmits the route calculation response information to the start node 3a that has transmitted the route calculation request information (S14).

  The path setting operation by the path setting unit 12 will be described below. The start node 3a transmits path setting request information to the node 3b (S15). The node 3b transmits path setting request information to the node 3d (S16). The node 3d specifies a route for the path 5 of the path setting request information (S17). The node 3d transmits path setting request information to the node 3f (S18). The node 3f transmits path setting request information to the node 3h (S19).

  The node 3h specifies a route for the path 5 of the path setting request information (S20). The node 3h transmits path setting request information to the end node 3i (S21). The end node 3i transmits path setting response information to the node 3h (S22). The node 3h transmits path setting response information to the node 3f (S23).

  The node 3f transmits path setting response information to the node 3d (S24). The node 3d transmits path setting response information to the node 3b (S25). The node 3b transmits path setting response information to the start point node 3a (S26).

  Hereinafter, with reference to FIG. 5, the route concealment processing (S8, S11) and the route identification processing (S17, S20) of FIG. 4 in the present embodiment will be specifically described. FIG. 5 illustrates the operations (S11, S17) focusing on the domain 1b (node 3d, path calculation device 2b, node 3f). Note that the operation (S8, S20) focusing on the domain 1c has the same operation contents, and the main subject of the operation is replaced by the node 3d → node 3h, the route calculation device 2b → the route calculation device 2c, and the node 3f → node 3i. ing.

  FIG. 5A is a flowchart showing details of the route concealment process (S11). The route calculation device 2b encrypts the route calculation result by the encryption unit 38 (S101). The route calculation device 2b includes the encrypted route calculation result in the route calculation response information (S102).

  FIG. 5B is a flowchart showing details of the route specifying process (S17). The route calculation device 2b extracts the information encrypted in S101 from the path setting request information (S111), and acquires the route calculation result by decrypting the extracted information by the decryption means 16 (S112). Based on the obtained information, the path 5 is identified. In the example of FIG. 1, the encrypted information of the link 4f is decrypted at the node 3d, and the encrypted information of the link 4k is decrypted at the node 3h. Note that the encryption key and the decryption key in the encryption method are managed in advance in association between devices belonging to the same domain 1.

  Hereinafter, a second embodiment of the present invention will be described with reference to FIGS. The second embodiment is characterized in that the node 3 of its own domain 1 transmits a route inquiry to the route calculation device 2 as a method of acquiring the route calculation result of the route calculation device 2 of its own domain 1.

  FIG. 6 is a configuration diagram illustrating the node 3. The node 3 includes a path setting unit 12, a route calculation request unit 14, a route inquiry unit 20, and a path DB 18. Compared to the first embodiment, there is no decryption means 16 and a route inquiry means 20 is added.

  When the link 4 indicated by the route included in the path setting request information is not link information connected to the node 3 or when the route included in the path setting request information is empty, the route inquiry unit 20 Route inquiry information for inquiring a route for reaching the link 4 included in the path setting request information to the route calculation device 2 of the domain 1 to which the node 3 belongs, and the route calculation device of the domain 1 to which the node 3 belongs 2 receives route inquiry response information.

  The route inquiry information includes a start node ID, an end node ID, and a path identifier. The route inquiry response information includes a route. In the example of FIG. 1, when the node 3d receives the path setting request information in which the link 4 indicating the route is “link 4j”, the node 3d transmits the route inquiry information to the relay route calculation device 2b.

  The route inquiry unit 20 may have the same configuration as the route calculation request unit 14. In addition, the route calculation request information transmitted by the route calculation request unit 14 is expanded to include a path identifier.

  FIG. 7 is a configuration diagram showing the route calculation device 2. The route calculation device 2 includes a route calculation request processing unit 32, a route calculation unit 34, a route calculation request unit 36, a route concealment unit 40, a route inquiry processing unit 46, a path storage unit 48, a link DB 42, a reachability DB 44, and a path. It is configured including the DB 18 (see FIG. 6). Compared to the first embodiment, there is no encryption unit 38, a route inquiry processing unit 46, a path storage unit 48, and a path DB 18 are added, and the route calculation request information transmitted by the route calculation request unit 36 is different. , Extended to include path identifiers.

  The route inquiry processing means 46 receives route inquiry information from the node 3, searches the path DB 18 for the corresponding path 5 using the start node ID, the end node ID, and the path identifier as search keys, and is searched for the node 3. The route inquiry response information including the route is sent.

  The path storage means 48 stores the path information inside the domain in the path DB 18 together with the start node ID, end node ID, path identifier, and bandwidth included in the path calculation request information. The section encrypted by the encryption means 38 in claim 1 corresponds to this.

  FIG. 8 is a flowchart showing a part of the path setting process of FIG. The route calculation result of path 5 is <link 4a → link 4c → link 4f → link 4j → link 4k>. The link 4f and the link 4k are hidden.

  Hereinafter, with reference to FIG. 8, the route concealment processing (S8, S11) and the route identification processing (S17, S20) of FIG. 4 in the present embodiment will be specifically described. FIG. 8 illustrates the operations (S11, S17) focusing on the domain 1b (node 3d, path calculation device 2b, node 3f). Note that the operation (S8, S20) focusing on the domain 1c has the same operation contents, and the main subject of the operation is replaced by the node 3d → node 3h, the route calculation device 2b → the route calculation device 2c, and the node 3f → node 3i. ing.

  FIG. 8A is a flowchart showing details of the route concealment process (S11). The route calculation device 2b stores the path of the route calculation result by the path storage means 48 (S121).

  FIG. 8B is a flowchart showing details of the route specifying process (S17). When the node 3d receives “link 4j” as a path included in the path setting request information at the path setting means 12, and determines that the “link 4j” is not connected to the node 3d, the path inquiry means 20 Then, route inquiry information is transmitted to the route calculation device 2b (S131).

  Upon receiving the route inquiry information, the route calculation device 2b searches the path DB 18 by the route inquiry processing means 46, and acquires “link 4f” as the route calculation result (S132). The route calculation device 2b transmits route inquiry response information including the acquired route calculation result to the node 3d (S133). The node 3d identifies the path 5 based on the transmitted information.

  Hereinafter, a third embodiment of the present invention will be described with reference to FIGS. 9 to 12. The third embodiment is characterized in that the node 3 of its own domain 1 receives a notification of the route calculation result from the route calculation device 2 as a method of acquiring the route calculation result of the route calculation device 2 of its own domain 1. To do.

  As shown in FIG. 9, in the third embodiment, the path 5a from the start node 3a to the end node 3i is configured using the preset paths 6a, 6b, and 6c. However, the preset path may not be in the domain to which the start node belongs (6a in the example in the figure). The preset path 6 is a path 5 that is set on the path 5 (overall path 5) from the start point to the end point and becomes a part of the entire path 5, and is set before the set time of the entire path 5 ( Set in advance).

  FIG. 10 is a configuration diagram illustrating the node 3. The node 3 includes a path setting means 12, a route calculation requesting means 14, a path setting instruction processing means 22, a path DB 18, and a preset path DB 24. Compared to the second embodiment, there is no route inquiry means 20, and a path setting instruction processing means 22 and a preset path DB 24 are added.

  The path setting instruction processing means 22 receives the path setting instruction information from the route calculation device 2 and transmits the path setting instruction response information, so that the edge from the edge of the domain 1 that is an intermediate section of the path 5 to be set The preset path 6 is set, and the set path information is stored in the preset path DB 24. Specifically, the path setting instruction information including the start point node ID, the end point node ID, the path identifier, the reaching link ID, the start point node ID of the preset path 6, the end point node ID of the preset path 6, the route, and the bandwidth is received. Then, the path setting unit 12 requests the path setting unit 12 by passing the start node ID of the preset path 6, the end node ID of the preset path 6, the route, and the bandwidth to the path setting unit 12. The path setting instruction processing means 22 stores the start node ID, the end node ID, the path identifier, and the arrival link 4 included in the path setting instruction information in the preset path DB 24 in response to the result stored in the path DB 18. The path setting instruction response information is transmitted to the route calculation device 2.

  The preset path DB 24 stores path information set in advance between the edges of the domain 1 when the path setting instruction processing unit 22 receives the path setting instruction information. The start point node ID, end point node ID, and path identifier are the start point node ID, end point node ID, and path identifier of the path 5 set across the plurality of domains 1 after the preset path 6 is set. The reached link ID is an identifier of the link 4 that can be reached using the preset path 6.

  In the example of FIG. 9, the node 3d receives from the relay route calculation device 2b the start node ID = “start node 3a”, the end node ID = “end node 3i”, the path identifier = “X”, and the reached link ID = “link”. 4j ”, the node ID of the preset path 6 =“ node 3d ”, the node ID of the preset node 6 =“ node 3f ”, and the path =“ link 4f ”are received, and the node 3d To the node 3f, the preset path 6 is set, and in the preset path DB 24, the start node ID = “start node 3a”, the end node ID = “end node 3i”, the path identifier = “X”, and the reached link ID = “ The information “link 4j” is stored.

  FIG. 11 is a configuration diagram showing the route calculation apparatus 2. The route calculation apparatus 2 includes a route calculation request processing unit 32, a route calculation unit 34, a route calculation request unit 36, a route concealment unit 40, a path setting instruction unit 52, a link DB 42, and a reachability DB 44. As compared with the second embodiment, the route inquiry processing unit 46, the path storage unit 48, and the path DB 18 are deleted, and a path setting instruction unit 52 is added.

  The path setting instruction means 52 transmits the path setting instruction information to the node 3 and receives the path setting instruction response information from the node 3 so as to set the route section inside the domain in advance in the route calculation result. To do. The section in which the path 5 is set in advance by the path setting instruction unit 52 corresponds to the section encrypted by the encryption unit 38 in the first embodiment. The path setting instruction unit 52 executes path setting processing in the following three cases.

  Case 1 (start point route calculation device 2a) is a case where the node 3 indicated by the start point node ID included in the received route calculation request information is in its own domain. In this case 1, the path setting instruction unit 52 does not perform processing.

  Case 2 (end point route calculation device 2c) is a case other than Case 1, where node 3 indicated by the end point node ID included in the received route calculation request information is in its own domain. In this case 2, the path setting instructing means 52 uses the node 3 belonging to its own domain 1 connected to the node 3 belonging to the domain 1 to which the route calculating apparatus 2 that transmitted the route calculation request information belongs as the starting node of the preset path 6 The end point node ID included in the ID and route calculation request information is set as the end point node ID of the preset path 6. For example, in the example of FIG. 9, the start point node ID of the preset path 6c = “node 3h”, and the end point node ID of the preset path 6c = “end point node 3i”.

  Case 3 (relay route calculation apparatus 2b) is a case other than Case 1 and Case 2, where the node 3 indicated by the end node ID included in the received route calculation request information is not in its own domain. In this case 3, the path setting instructing means 52 uses the node 3 belonging to its own domain 1 connected to the domain 1 to which the route calculating apparatus 2 that transmitted the route calculation request information belongs as the starting node ID of the preset path 6 and the route calculation. The node 3 in the own domain 1 connected to the node 3 belonging to the domain 1 to be reached to reach the end node ID included in the request information is set as the end node ID of the preset path 6. The starting node ID of the preset path 6b = “node 3d”, the end node ID of the preset path 6b = “node 3f”, and the starting node ID of the preset path 6 (not shown) = “node 3c”, the preset path 6 end node ID = “node 3g”.

  The path setting instruction information includes the start node ID of the preset path 6 and the end node ID of the preset path 6, and the start node ID, end node ID, path identifier, bandwidth, and route calculation included in the route calculation request information. The path setting instruction information including the path inside the domain among the paths stopped by the means 34 is transmitted to the node 3 indicated by the starting node ID of the preset path 6.

  FIG. 12 is a flowchart showing a part of the path setting process of FIG. The route calculation result of path 5 is <link 4a → link 4c → link 4f → link 4j → link 4k>. The link 4a, the link 4f, and the link 4k become the preset path 6.

  Hereinafter, with reference to FIG. 12, the route concealment processing (S8, S11) and the route identification processing (S17, S20) of FIG. 4 in the present embodiment will be specifically described. FIG. 12 illustrates the operations (S11, S17) focusing on the domain 1b (node 3d, path calculation device 2b, node 3f). Note that the operation (S8, S20) focusing on the domain 1c has the same operation contents, and the main subject of the operation is replaced by the node 3d → node 3h, the route calculation device 2b → the route calculation device 2c, and the node 3f → node 3i. ing.

  FIG. 12A is a flowchart showing details of the route concealment process (S11). The route calculation device 2b transmits the preset path setting instruction information to the path setting instruction processing unit 22 of the node 3d based on the route calculation result by the path setting instruction unit 52 (S141). The node 3d transmits the preset path setting request information to the node 3f by the path setting means 12 (S142), and receives preset path setting response information as a response (S143). The node 3d stores the path information set in the path DB 18 by the path setting unit 12, and the path setting instruction processing unit 22 stores the information in the preset path DB 24. The node 3d transmits the path setting instruction response information to the route calculation device 2b by the path setting instruction processing unit 22 (S144).

  FIG. 12B is a flowchart showing details of the route specifying process (S17). When the path setting request information is received by the path setting unit 12, the node 3 d searches for the corresponding path information from the preset path DB 24. When the node 3d finds the corresponding path information, the node 3d checks whether the route link 4 included in the path setting request information matches the arrival link 4 of the path information searched in the preset path DB 24. If they match, the corresponding path 5 is used, so path setting request information is created based on the preset path 6 (S151).

  The embodiments of the present invention have been described above. FIG. 13 is a network configuration diagram for comparing the embodiment of the present invention with a comparative example. This configuration diagram shows two paths 5 (path 5b, path 5c) passing from the start node 3a to the end node 3i. The two paths 5 share the start and end points, but the links 4 to be relayed are partially different. The node 3d selects two routes in order to reach the link 4i. Therefore, in the embodiment of the present invention, the optimum route (path 5b) calculated by the route calculation device 2b is selected, but in the comparative example, the inefficient route (path 5c) calculated by the node 3d is selected.

  The present invention described above can be widely modified without departing from the spirit thereof as follows.

  For example, the node ID corresponds to an IP address or the like. In addition, as an IF-ID (Interface-ID), for example, a simple number or an IP address corresponds. The path identifier may be set by the operator, or may be dynamically paid out.

  The device configuration of the route calculation device 2 may be a physical device (housing) different from that of the node 3, or may be the same (integrated) physical device (housing) as the node 3. It doesn't matter. Further, a configuration may be adopted in which a plurality of route calculation devices 2 exist in one domain 1 for redundancy and load distribution.

  Further, the node 3 includes, for example, a layer 2 switch, a TDM cross-connect, a wavelength cross-connect, an MPLS (Multi Protocol Label Switching) LSR (Label Switching Router), and the like. The link 4 is composed of an optical fiber or the like.

  In the third embodiment, the path 5 is set from edge to edge in each domain 1 in advance. However, since there are cases where the path 5 is not actually used, for example, a timer is set in the preset path DB 24 of the node 3, The preset path 6 that is not used after a predetermined time may be deleted.

  Further, in the present embodiment, a first customer device and a second customer device are provided in a network in which a UNI-IF (User Network Interface) is provided between the provider network and the customer network, and the provider network information is hidden in the customer network. Similarly, the present invention can be applied to a system in which the path 5 is set.

  Further, a redundant configuration of the path 5 may be constructed to improve the reliability to the failure. For example, a working path and a backup path that does not share the working path and the relay node can be set between the start node 3a and the end node 3i.

It is a block diagram which shows the path | pass setting system regarding one Embodiment of this invention. It is a block diagram which shows the node regarding 1st Embodiment of this invention. It is a block diagram which shows the route calculation apparatus regarding 1st Embodiment of this invention. It is a flowchart which shows the path | pass setting process regarding 1st Embodiment of this invention. It is a flowchart which shows the path | route concealment process (a) and path | route identification process (b) of the path | pass setting process regarding 1st Embodiment of this invention. It is a block diagram which shows the node regarding 2nd Embodiment of this invention. It is a block diagram which shows the route calculation apparatus regarding 2nd Embodiment of this invention. It is a flowchart which shows the path | route concealment process (a) of the path | pass setting process regarding 2nd Embodiment of this invention, and a path | route specific process (b). It is a block diagram which shows the path setting system by which the preset path | pass regarding 3rd Embodiment of this invention is set. It is a block diagram which shows the node regarding 3rd Embodiment of this invention. It is a block diagram which shows the route calculation apparatus regarding 3rd Embodiment of this invention. It is a flowchart which shows the path | route concealment process (a) and path | route specific process (b) of the path | pass setting process regarding 3rd Embodiment of this invention. It is explanatory drawing which shows the comparison of the setting of the path | pass regarding one Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Domain 2 Path | route calculation apparatus 3 Node 4 Link 5 Path 6 Preset path 12 Path setting means 14 Path calculation request means 16 Decoding means 18 Path DB
20 route inquiry means 22 path setting instruction processing means 24 preset path DB
32 Route calculation request processing means 34 Route calculation means 36 Route calculation request means 38 Encryption means 40 Path concealment means 42 Link DB
44 Reachability DB
46 route inquiry processing means 48 path storage means 52 path setting instruction means

Claims (8)

In a network system where the start point domain to which the start point node that is the start point of the path belongs and the end point domain to which the end point node that is the end point of the path belongs are different domains, the path is calculated based on the route calculation result calculated by the route calculation device of each domain. A path setting system for setting
The route calculation device for each domain is:
Route calculation means for calculating the route calculation result of the path of the own domain with reference to the network configuration of the own domain;
A route concealment means for concealing a result of the route calculation from a node of the own domain and concealing from a node of another domain;
The nodes in each domain are
A path setting system comprising path setting means for setting a path based on the route calculation result concealed by the route concealing means in the node of the other domain. The route concealing means has an encryption means for encrypting the route calculation result,
The path setting system according to claim 1, wherein the path setting unit includes a decrypting unit that decrypts the route calculation result of the own domain encrypted by the encryption unit. The route concealing means has path storage means for storing the route calculation result in a storage means,
The path setting system according to claim 1, wherein the path setting unit includes a route inquiry unit that acquires the route calculation result stored by the path storage unit by inquiring the route calculation device. The route concealing means has path setting instruction means for causing the node to set a preset path that is a part of a path based on the route calculation result in the own domain,
The path setting means includes path setting instruction processing means for setting a preset path according to an instruction from the path setting instruction means, and sets a path based on the preset path. 1. The path setting system according to 1.   5. The path setting system according to claim 4, wherein the path setting instruction processing means sets a timer for the set preset path and deletes the preset path that is not used after a predetermined time has elapsed.   6. The path set from the start node to the end node is set as a plurality of redundant paths that do not share the nodes that relay each other. Path setting system.   The path setting system according to any one of claims 1 to 6, wherein the route calculation device and the node belonging to the same domain are configured as a single casing. In a network system where the start point domain to which the start point node that is the start point of the path belongs and the end point domain to which the end point node that is the end point of the path belongs are different domains, the path is calculated based on the route calculation result calculated by the route calculation device of each domain. A path setting method for setting
The route calculation device of each domain is
A procedure for calculating the route calculation result of the path of the own domain and storing it in the storage means with reference to the network configuration of the own domain;
The route calculation result is used by a node in the own domain and is concealed from a node in another domain, and
The nodes in each domain are
A path setting method comprising: performing a path setting procedure based on the route calculation result concealed by the node of the other domain by the route calculation device.

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