JP2008187445A - Path grasping method and device in dynamic routing on ip network and its program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and instantaneously grasp a communication path of End-to-End even if communication becomes temporarily impossible, or communication is completely disconnected in the dynamic routing of an IP network. <P>SOLUTION: The information of each node is collected and analyzed on a network adopting dynamic routing so that the communication path of End-to-End can be managed as a logical path, and the latest routing information is acquired from the start edge node and the terminal node of each path so that communicating circumstances on the path can be accurately and easily grasped. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a route grasping method, apparatus and program for dynamic routing on an IP network, and more particularly to a route grasping method, apparatus and program for dynamic routing on an IP network for detecting a faulty node.

  Among IP networks adopting conventional dynamic routing, a network adopting dynamic routing will be described below with reference to FIG.

  Conventionally, in an IP network, reliability is enhanced by adopting various redundant configurations, and then end-to-end communication is realized.

  In this regard, it is a premise that a plurality of detour paths having a redundant configuration are prepared basically on a network adopting dynamic routing among IP networks. When a failure of a configuration node occurs on the network, the end-to-end communication path automatically bypasses the configuration node where the failure has occurred.

  In principle, a communication path on a network adopting dynamic routing is usually uniquely determined based on the cost value of the interface set in the node configuration. However, sometimes a communication path on the network is changed in accordance with a node or link failure or a network configuration change (for example, Patent Document 1).

  When the communication path on the network is switched, communication is temporarily disabled until the routing information exchange process (advertising) is settled. Further, when a plurality of faults or planned outages occur, the communication path may be completely interrupted even if various redundant configurations are taken (for example, Patent Document 2).

When a communication path on the network is changed due to such a node or link failure or a network configuration change, it is difficult to grasp an accurate path particularly in a large-scale network. This is because in order to grasp the situation, it is necessary to analyze the configuration of each node and perform a simulation of advertising operations over time. At this time, the larger the network scale, The absolute number will also increase. As a result, the time required to analyze the configuration of each node also increases.
JP 2006-074310 A Japanese Patent Laid-Open No. 10-285207

  As described above, the method for grasping the end-to-end communication path on the network adopting the conventional dynamic routing is based on the cost value of each route obtained by analyzing the configuration of the configuration node. This is a logical method.

  In this regard, what can be obtained by this method is a theoretical value to the last, and therefore, there is a possibility that synchronization may be lost with the actual network situation.

  In addition, as described above, in order to grasp the change in the communication path due to the occurrence of the failure, the advertising operation simulation assuming the failure location from the configuration of the configuration node is performed. It takes a long time.

  On the other hand, in recent years, the number of cases where a relatively low cost IP network is introduced for communication within a private network is increasing for cost reduction. The IP network is also being studied as a target of network means for more important information that requires high reliability.

  However, as described above, the reliability of dynamic routing is low, so at least for important communication, the end-to-end communication path is grasped and communication is temporarily disabled or communication is completely interrupted. There is a demand for a method for easily and immediately grasping the above.

  Therefore, the present invention provides a method, system and program for easily and immediately grasping an end-to-end communication path even when communication is temporarily disabled or communication is completely interrupted. The purpose is to provide.

  According to the present invention, there is provided a route grasping method in dynamic routing on an IP network, the step of specifying a start node and a terminal node based on path information, and obtaining routing table information from the start node or the terminal node. A next hop identifying step for identifying a node adjacent to a node on the side from which the routing table information has been acquired, of the start node or the end node based on the acquired routing table information, and the specified next hop A path information storing step for storing node information, and a step of repeating the next hop specifying step and the path information storing step until reaching a node that is not the side from which the routing table information is acquired, among the nodes or terminal nodes. Preparation Route grasping wherein the Rukoto, its apparatus and its program is provided.

  In the route grasp method described above, when there is a change in the route information on the network, the step of acquiring information based on the change, the information based on the acquired change, and the acquired route information And a step of extracting an affected path.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to grasp | ascertain rapidly the communication path from the start end to the termination | terminus in routing on an IP network.

  Next, the best mode of the present invention will be described with reference to the drawings.

  In the following, L2 refers to Datalink layer. Here, Datalink layer refers to a data communication model located in the second layer in the OSI reference model.

In the following, L3 refers to Network layer. Here, “Network layer” refers to a data communication model located in the third layer in the OSI reference model.
[Embodiment 1]
(Embodiment 1-1) Configuration of Embodiment The configuration of the embodiment of the present invention will be described in detail with reference to FIG. 1, FIG. 4, FIG. 5, and FIG. FIG. 2 is a conceptual diagram of the present invention. The embodiment of the present invention includes a path information management unit 10, a Telnet acquisition processing unit 20, a routing table analysis processing unit 30, a route information storage unit 40, a network address / management IP address information management unit 50, a link Connection information management unit 60, node discrimination information management unit 70, map display processing unit 80, failure information management unit 90, network configuration change information management unit 100, influence path extraction processing unit 110, timer processing unit 120 And a path list display processing unit 130.

  The path information management unit 10 is a part that manages the IP address information and subnet mask information of the start L3 node and the end L3 node constituting the management target path for all managed paths.

  The Telnet acquisition processing unit 20 is a part having a function of performing Telnet login to the L3 node and acquiring routing information.

  The routing table analysis processing unit 30 has a function of extracting a destination address from the acquired routing information and a function of analyzing next hop information.

  The route information storage unit 40 stores and holds communication route (L2 node, L3 node and its interface) information from the start end to the end of all the paths to be managed arbitrarily or periodically.

  The network address / management IP address information management unit 50 manages the management IP address and interface address held by the node as configuration information for each node in units of nodes.

  The link connection information management unit 60 holds connection information between nodes in units of physical interfaces such as L2 nodes and L3 nodes. The node discrimination information management unit 70 is information for identifying whether a certain node is an L2 node or an L3 node. The map display processing unit 80 is a part that displays route information on the map screen.

  The failure information management unit 90 is a part that manages the latest failure information of a node or interface that has occurred by being directly received from each node on the network or transferred from an external SNMP manager.

  The network configuration change information management unit 100 is a part that receives and manages a notification that a node or interface has been newly detected by an external SNMP manager or the like. That is, it is a part that grasps and manages the latest change information of the network configuration.

  The affected path extraction processing unit 110 searches for route information including a node or interface in which a failure has occurred or has been recovered. Then, based on the search information, it is a part for extracting paths that may have been switched or disrupted.

  The timer processing unit 120 is a part that measures a time that is assumed to be required for completion of convergence of the routing table when a communication failure occurs on the network. The path list display processing unit 130 is a part that displays the communication status for all the extracted paths in the path list.

As mentioned above, this invention is provided with the combination of each said information part and management part of said 10-130.
(Embodiment 1-2) Operation of Embodiment The operation of the embodiment will be described with reference to FIGS. 4, 5, and 6. FIG. First, for the specified path, the IP address and subnet mask of the L3 node at the start and the L3 node at the end are acquired from the path information management unit 10 (S10).

  Next, in order to examine the upstream route, the Telnet acquisition processing unit 20 logs in to the start node, and issues a command in the Telnet acquisition processing unit 20 to acquire routing table information (S20).

  Then, in the routing table analysis processing unit 30, whether the network address derived from the IP address and subnet mask of the terminal node exists in the network address of the destination described in the acquired routing table information Confirm. If it does not exist, it is determined that the path is broken and nothing is displayed on the map screen. (S30).

  On the other hand, if there is a network address derived from the IP address and subnet mask of the terminal node, the IP address (or host name) of the starting node is recorded in the path information storage unit 40 (S40).

  Next, the routing table analysis processing unit 30 acquires the interface address of the L3 node that is the first next hop of the starting node from the routing table (S50). Here, the next hop refers to an interface address of an L3 node (for example, a router) to be relayed next to reach the terminal node.

  Further, the routing table analysis processing unit 30 obtains the management IP address corresponding to the L3 node having the interface address of the L3 node that is the first next hop of the start node from the network address / management IP information management unit 50. Obtain (S60). In addition, the routing table analysis processing unit 30 refers to the link connection information management unit 60, and the interface address of the L3 node serving as the first next hop of the start node exists in the physical link information of the start node. (S70).

  If it does not exist, it is determined that there is an L2 node between the starting node and the L3 node of the first next hop, and the node identification information management unit 70 is used to store the physical link information in the starting node. Only the L2 node in (2) is extracted (S80).

  Further, the routing table analysis processing unit 30 refers to the link connection information management unit 60, and the management IP address of the L3 node serving as the first next hop is included in the extracted physical link information of the L2 node. It is confirmed whether it exists (S90).

  If it does not exist, it is determined that there is another L2 node with the L3 node of the first next hop, and the L2 node in the physical link information of the L2 node using the node discrimination information management unit 70 The same process (S60, S70, S80, and S90) is repeated until the management IP address of the L3 node that becomes the first next hop is found (S100).

  If the management IP address of the L3 node is found as a result of the above repeated processing, the interface name on the start node side, the IP addresses (or host names) of all adjacent L2 nodes passed so far, and L2 The node side interface name, the L3 node IP address (or host name), and the L3 node side interface name are recorded in the path information storage unit 40 (S110).

  The following operation will be described with reference to FIG.

  Then, it is confirmed whether the management IP address of the L3 node is the same as the management IP address of the terminal node. If they are identical, the route search is completed. On the other hand, if they are not the same, the Telnet acquisition processing unit 20 next logs in to the L3 node of the first next hop and issues a command in the Telnet acquisition processing unit 20 to acquire the routing table information. (S120).

  Next, the routing table analysis processing unit 30 confirms whether the network address derived from the IP address and subnet mask of the terminal node exists in the destination in the routing information (Destination). The interface address of the L3 node that is the next hop of the th next hop (that is, the second next hop from the start node) is acquired (S130).

  Then, based on the acquired interface address, the management IP address of the L3 node having the acquired interface address is acquired from the network address / management IP information management unit 50 (S140).

  If the address is not the terminal node address, the link connection information management unit 60 is referred to and it is confirmed whether the physical link information of the second L3 node exists in the physical link information of the first L3 node ( S150). If not, it is determined that there is an L2 node with the next hop L3 node as in S80, and the steps S80, S90, and S100 are performed for the first next hop L3 node. carry out.

  The same is true in that the same processing is repeated until the management IP address of the L3 node that becomes the next hop (the node that becomes the second next hop from the start node) is found (S160).

  If the management IP address of the L3 node of the next hop of the first next hop (as described above, the second next hop from the start node) is found as a result of performing the above procedure, the next hop L3 node side interface name, IP addresses (or host names) of all adjacent L2 nodes that have passed so far, L2 node side interface names, L3 node IP addresses (or host names), L3 node side Are recorded in the path information storage unit 40 (S170).

  Further, it is confirmed whether the management IP address of the L3 node that is the next hop of the first next hop is the same as the management IP address of the terminal node (when the same is found here, the route search is completed). Become). On the other hand, if they are not the same, the steps S130, S140, S150, S160, S170, and S180 are repeatedly executed for the L3 node that is the next hop of the first next hop (S180).

  Next, in order to check the downstream route, the Telnet acquisition processing unit 20 performs Telnet login to the terminal node, issues a command to acquire the routing table information, and the management IP address of the next hop L3 node is The steps S130, S140, S150, S160, S170, and S180 are executed in the same manner as the search for the upstream route until the node management IP address is the same (S190).

When the route search for the up route and the down route is completed by the above means, the map display processing unit 80 displays the route of the path on the map screen.
(Embodiment 1-3) Second operation of Embodiment 1 In the second operation of Embodiment 1, an operation for extracting a path affected by a failure at high speed will be described. Refer to FIGS. 7 and 8 for the description.

  First, the failure information management unit 90 receives information that a failure has occurred on the network from a node on the network or an SNMP manager by Trap. Further, the network configuration change information management unit 100 obtains the network configuration change information manually or from an SNMP manager (S210).

  Next, the affected path extraction processing unit 110 routes the node or interface where the failure has occurred or has been recovered based on the route information recorded in the route information storage unit 40 before the occurrence of the failure or the recovery from the failure. Automatically search for paths included in. Then, the path including the node or interface where the failure has occurred or recovered is extracted as a path that may have been switched or disrupted (S220).

  In the worst case, the extracted path stops for several tens of seconds regardless of whether or not switching is possible. Therefore, the timer processing unit 120 performs a waiting process for a time (about 1 minute) that is assumed to be required until the routing table converges (S230).

  Then, the Telnet acquisition processing unit 20 performs Telnet login to the extracted start node of each path, and issues a command at the Telnet acquisition processing unit 20 to acquire routing table information (S240).

  Next, the routing table analysis processing unit 30 confirms whether the network address derived from the IP address and subnet mask of the terminal node exists in the destination in the routing information (Destination). Here, if the derived network address exists, it is determined that the path has been switched normally. On the other hand, if it does not exist, it is determined that the path has been interrupted (S250). For other paths as well, the above-described steps S240 and S250 are repeated in order, and the communication states for the upstream paths of all the extracted paths are determined (S260).

  Further, for the extracted path that is determined to have been switched normally, the Telnet acquisition processing unit 20 again logs in to the terminal node of the target path, and the Telnet acquisition processing unit 20 The command is issued to acquire the routing table information (S270).

  In addition, the routing table analysis processing unit 30 confirms whether the network address derived from the IP address and subnet mask of the start node exists in the destination in the routing information (Destination). Here, if it exists, it is determined that the path has been switched normally, and if it does not exist, it is determined that the path has been interrupted (S280).

For other paths as well, the above-described steps S240 and S250 are repeated in order, and the communication state for the downstream paths of all the extracted paths is determined (S290). Based on the results of S250, S260, S280, and S290, a path that can communicate normally in both uplink and downlink is determined to be normal. On the other hand, a path that has been interrupted on either the up or down side is determined to be abnormal. Then, the communication status for all paths extracted by the determination is displayed as a path list by the path list display processing unit 130.
[Embodiment 2]
An embodiment in the case where a redundant configuration with L2 nodes exists while searching for a route is as follows. Here, examples of the redundant configuration include a spanning tree and a ring format. Note that the spanning tree and the ring format are merely examples, and the configuration is not limited thereto.

  First, the master node in the node group configuring redundancy and the type of redundant configuration are recorded in advance as L2 redundant configuration information. When an L2 node is detected during the route search, it is confirmed what redundant configuration the node belongs to from the L2 redundant configuration information, and the redundant configuration master node is acquired.

  Further, the Telnet acquisition processing unit 20 logs in to the acquired master node, executes a command corresponding to the type of redundant configuration, and acquires the status of the redundant configuration. If the redundant configuration is normal, it is determined that a normal link is being used, and if it is abnormal, it is determined that a detour-side link is being used.

  Further, for the link determined to be used as a result of the determination, the connection destination L2 node is acquired from the link connection information and stored in the route information.

  Even if there is a redundant configuration with L2 nodes while searching for a route by using the route information accumulated by using the above means, the route currently used It is possible to determine and grasp whether the link is a normal link or a link on the detour side. Thereby, the purpose of confirming the route state in both the uplink and the downlink can be achieved.

  As described above, according to the present invention, an end-to-end communication path is managed as a logical path by collecting and analyzing information held by each node on a network employing dynamic routing. In addition, by acquiring the latest routing information from the start node and the end node of each path, it is possible to accurately and easily grasp the communication status on the path.

  Further, by periodically collecting and accumulating the route information, it becomes possible to extract a path affected by the failed node at high speed.

  In addition, even when a redundant configuration with an L2 node exists while searching for a route, the master node of the redundant configuration is acquired from the L2 redundant configuration information, and the status of the redundant configuration is further updated. By determining, it can be determined whether a normal link or a detour-side link is currently used. Therefore, as in the case where no redundant configuration exists, the communication status on the path can be accurately and easily grasped.

It is a figure showing the basic composition of the present invention. It is a conceptual diagram showing the fundamental structure of this invention. It is a figure showing the path | route grasping method of a prior art. It is an operation | movement diagram for demonstrating embodiment of this invention. It is an operation | movement diagram for demonstrating embodiment of this invention. It is an operation | movement diagram for demonstrating embodiment of this invention. It is an operation | movement diagram for demonstrating embodiment of this invention. It is an operation | movement diagram for demonstrating embodiment of this invention.

Explanation of symbols

10 path information management unit 20 Telnet acquisition processing unit 30 routing table analysis processing unit 40 route information storage unit 50 network address / management IP address information management unit 60 link connection information management unit 70 node discrimination information management unit 80 map display processing unit 90 Failure information management unit 100 Network configuration change information management unit 110 Influence path extraction processing unit 120 Timer processing unit 130 Path list display processing unit

Claims (15)

A method for grasping a route in dynamic routing on an IP network,
Identifying the start and end nodes based on the path information;
Obtaining routing table information from the start node or end node;
Based on the acquired routing table information, a next hop specifying step for specifying a node adjacent to the node on the side from which the routing table information has been acquired, of the start node or the end node,
A path information storing step for storing node information of the specified next hop;
Repeating the next hop identification step and the path information storage step until reaching the node that is not the side from which the routing table information has been acquired, of the start node or the end node;
A route grasping method characterized by comprising: A route grasping method according to claim 1,
The route grasping method characterized in that the route information stored in the route information storing step is a node name, an interface name, an IP address or a host name through which the route information is passed. A route grasping method according to claim 1 or 2,
When there is a change in route information on the network, the step of knowing the fact that the change has occurred,
A route grasping method, further comprising: a step of extracting the changed path based on the information based on the obtained change and the acquired route information.   4. The route grasping method according to claim 3, wherein the change of the route information is when a failure occurs on the network or when the failure is recovered. The route grasping method according to claim 3 or 4, wherein the communication state is determined for the uplink route and the downlink route of all the extracted paths;
And a step of displaying the determined communication status as a list. A route grasping method according to any one of claims 3 to 5,
When a redundant configuration exists in the network at the time of performing the route grasping method, storing the type of the redundant configuration and information on the master node in advance;
Log in to the master node, and check the current redundant configuration status.
A route grasping method, further comprising:   The route grasping method according to any one of claims 1 to 6, wherein the step of acquiring the routing table information is performed by logging in to the start node or the end node through a Telnet connection. How to grasp the route. A program for causing a route grasping apparatus in dynamic routing on an IP network to execute the route grasping method according to any one of claims 1 to 7. A route grasping device for dynamic routing on an IP network,
Means for identifying the start and end nodes based on the path information;
Means for obtaining routing table information from the start node or end node;
Based on the acquired routing table information, the next hop specifying means for specifying a node adjacent to the node on the side from which the routing table information has been acquired, of the start node or the end node,
Route information storage means for storing node information of the specified next hop;
Means for repeating the next hop specifying means and the path information storage means until reaching a node that is not the side from which the routing table information has been acquired, of the start node or the end node;
A route grasping device characterized by comprising: The route grasping device according to claim 9,
The route grasping device characterized in that the route information stored in the route information storage means is a node name, an interface name, an IP address or a host name through which the route information is stored. The route grasping device according to claim 9 or 10,
When there is a change in the route information on the network, a means to know the fact that the change has occurred,
A route grasping device, further comprising: means for extracting a path that has received the change based on the information based on the obtained change and the acquired route information.   12. The route grasping device according to claim 11, wherein the change of the route information is when a failure occurs on the network or when the failure is recovered. The route grasping device according to claim 11 or 12, wherein means for determining a communication state for an uplink route and a downlink route of all the extracted paths;
A route grasping device further comprising means for displaying the determined communication state as a list. A route grasping device according to any one of claims 11 to 13,
When a redundant configuration exists in the network at the time of implementing the route grasping device, means for storing the type of the redundant configuration and information on the master node in advance,
A redundant configuration state grasping means for logging in to the master node and confirming the current redundant configuration state;
A route grasping device further comprising:   The route grasping device according to any one of claims 9 to 14, wherein the means for acquiring the routing table information is performed by logging in to the start node or the end node through a Telnet connection. Route grasping device.

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