KR20090052512A - System and method for discovering network topology, storage medium recording that method program - Google Patents

Abstract

The present invention relates to a storage medium recording a topology detection system, a topology detection method and method program. According to the present invention, a second router, which is a immediately neighboring router of the first router, is detected, and an interface type between neighboring nodes is determined to detect a switch candidate in a broadcast period, and whether to support data link layer or IP packet forwarding. The entire topology can be detected by checking whether the switch is based on. The result is a way to get out of the way of spending a lot of time and putting a lot of load on your equipment, reducing the load, and finding the correct configuration of your switches and routers.

Description

Storage system recording network topology detection system, detection method and method program {SYSTEM AND METHOD FOR DISCOVERING NETWORK TOPOLOGY, STORAGE MEDIUM RECORDING THAT METHOD PROGRAM}

The present invention relates to a storage medium recording a network topology detection system, a detection method and a method program.

The network topology is represented by the connection of the switches of the router. In this case, the router or the switch may be represented by a node, and the connection between these devices may be represented by an edge. In other words, the connection between the router and the router constituting the network, the connection between the router and the switch, and the connection between the switch and the switch can be represented by a graph composed of edges.

Conventionally, a network topology is detected with reference to a routing table included in a router. In the routing table, there are a destination (ipRouteDest) item and a nextRoute (ipRouteNext Hop) item. In the next hop (ipRouteNextHop) item, there are gateway addresses to all networks in the routing table. Therefore, to find the actual NextHop, it is necessary to search all the destinations (ipRouteDest), find the network next to the actual, and find the corresponding NextHop IP. rm The result can be a heavy load on a backbone network consisting of hundreds of routers and switches.

In addition, the conventional topology detection method is a router-oriented detection method, and considering that the actual network is composed of a router and a switch, it cannot be called an accurate topology detection method.

In addition, in order to detect a switch on a conventional network, all devices in the IP band of a specific interface were tested for the switch. This also has a problem that it takes too much load and takes a long time in a large backbone network.

Accordingly, the technical problem to be achieved by the present invention is to be able to detect the network topology while reducing the load on the backbone network.

In addition, the technical problem to be achieved by the present invention is to be able to accurately detect the network topology consisting of a router and a switch.

The topology detection system according to an embodiment of the present invention for achieving the above technical problem, detects the second router that is the immediate neighbor router of the first router, the data link layer support or IP when the interface type between nodes is a broadcast period A topology detection server for detecting a network topology by detecting a switch based on whether packet forwarding is performed; And a topology information database that stores network topology information.

In addition, a method for detecting a topology according to an embodiment of the present invention for achieving the technical problem comprises the steps of: a) detecting a second router which is a immediately neighboring router of the first router; b) determining the interface type between neighbor nodes and detecting a switch candidate in the broadcast period; And c) determining whether to switch based on whether the data link layer is supported or whether IP packet forwarding is performed.

In addition, a storage medium according to an embodiment of the present invention for achieving the above technical problem is a storage medium recording a program for executing the method.

Therefore, according to the present invention, topology information for network management can be detected quickly. In particular, it is possible to find a faster and less accurate configuration of switches and routers while reducing the load, which is a long time and put a lot of load on the equipment.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding the other components unless otherwise stated. In addition, the terms ".. part", ".. group", "module", and the like described in the specification mean a unit for processing at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software. Can be.

Now with reference to the drawings with reference to the embodiment of the present invention will be described in detail.

1 is a diagram illustrating a network topology detection system 100 connected to a network according to an embodiment of the present invention.

As shown, the network topology detection system 100 may collect packet data from network equipment via an interface protocol. The topology detection system 100 may collect and store packet data from network equipment using various interface protocols such as CORBA, SNMP, and CLI.

The topology detection system 100 detects the entire topology of a network by finding a node connected to a neighbor at any node and forming a connection relationship between the two, and moving to a neighbor node to find a node connected to the neighbor node. The topology detection system 100 may detect the entire topology by performing a neighbor node search until there are no more neighbor nodes.

The topology detection system 100 may detect a topology more accurately by determining whether a switch exists in a neighboring node according to an interface type between nodes.

More specifically, the topology detection system 100 may include a topology detection server 110 and a topology information database 120.

The topology detection server 110 may collect packet data from network equipment using various interface protocols, and detect node information connected to the surroundings at any node. The topology detection server 110 may determine an interface type between nodes and determine whether a switch exists in a neighboring node according to the interface type.

The topology information database 120 may store packet data collected from the topology detection server 110, and may store information on any node and its neighbor nodes. The topology information database 120 may store connection information between all nodes on the network or accurate topology information about whether the corresponding node is a switch or a router.

More detailed information about the topology detection server 110 and the topology information database 120 will be described later.

As shown in FIG. 2, the topology detection server 110 may include a packet collection module 111, a neighbor node detection module 113, an interface analysis module 115, a switch detection module 117, and a topology configuration module 119. It may include.

The packet collection module 111 may collect packet data using various communication protocols from a router or a switch device.

The neighbor node detection module 113 may detect the neighbor router information directly on the routing protocol.

Meanwhile, a plurality of neighboring routers may be connected to one interface of any router through a switch.

The neighbor node detection module 113 may detect only the information of the router excluding the switch when the neighbor router is connected through at least one switch.

For example, if the neighbor node detection module 113 is an OSPF backbone network, the neighbor node detection module 113 may directly detect neighbor router information using OSPF neighbor information (ospfNbrIpAddr information) on SNMP. In this case, since there is no switch in the OSPF neighbor information, a second or third router that exists after the switch connected to the first router may be detected as a neighboring router of the first router.

The interface analysis module 115 may analyze the connection type between the nodes, and may determine whether the connection method between the first router and the second router is a point-to-point or broadcast method.

For example, when the OSPF backbone network, the interface analysis module 115 may obtain an IP address (ipNetToMediaNetAddress) corresponding to a physical address on SNMP. In this case, the interface analysis module 115 may detect the addresses of devices connected to the first router and the broadcast interval. Can be. That is, when there is a management IP in the switch, the neighbor node detection module 113 may detect the addresses of devices such as a host PC and a router, including the presence of a switch that is not detected.

The interface analysis module 115 may extract the switch candidate by comparing the addresses of the devices connected in the broadcast interval with the addresses of the neighbor routers detected by the neighbor node detection module 113.

The switch detection module 117 may check whether the switch is performed by checking whether the switch candidate device supports the data link layer on the OSI 7 layer and whether IP packet forwarding is performed. That is, the switch may be determined when the IP packet forwarding is not performed while supporting the data link layer.

For example, you can check whether the switch is read by reading the sysService and ipForwarding values on SNMP for the switch candidate device.

sysService is a 7-bit value that indicates whether the OSI 7 layer is supported for each bit. Therefore, if the lower 2 bits of sysService are 1, it may mean that the switch operates as a switch supporting the data link layer.

 ipForwarding means whether to forward ip packet or not. If ipForwarding is 0, it means a switch.

The topology configuration module 119 may be configured as an entire router by adding neighboring nodes one by one from the root node by using any router as a root. To this end, the topology configuration module 119 may connect an edge between the first router and a second router detected as a immediately neighboring node of the first router.

In this case, when the connection between the first router and the second router is point-to-point, the topology configuration module 119 may connect the first router and the second router to an edge.

When the connection between the first router and the second router exists in the broadcast period, the topology configuration module 119 connects the first router and the switch to the edge and connects the switch and the second router to the edge. Can connect

As a result, the topology configuration module 119 can configure a topology in which neighboring nodes have been added in the previously obtained topology, and change the attribute to a completed node in the sense that the necessary information has been collected for the first router. Can be.

The topology configuration module 119 may perform the neighbor node survey as described above with respect to the second router as an unvisited node with respect to the newly added second router.

The topology configuration module 119 may expand the topology by repeating the above-described process with respect to the second router, and finish the topology configuration when there are no longer unvisited nodes for all nodes on the network. have.

 The topology information database 120 may include a packet storage unit 121, a neighbor node information storage unit 123, and a topology information storage unit 125.

The packet storage unit 121 may store packet data collected from a router or a switch device.

The neighbor node information storage unit 123 may store the detected immediate neighbor router information. That is, when the first router is the node to be examined, the neighboring router information about the first router may be stored, and after completion of the investigation of the first router, when the second router is the node to be examined, the second router may be directly to the second router. It can store neighbor router information.

That is, the neighbor node information storage unit 123 may immediately add and store neighbor router information when adding neighbor nodes from the root node.

The topology information storage unit 125 may store the detected topology information.

That is, the topology information storage unit 125 may store the entire topology information in which neighboring nodes are added from the root node. When the first router and the second router have a point-to-point connection interval, the topology information storage unit 125 may store the information between the first router and the second router. Edge connection information can be saved. When the switch between the first router and the second router exists in a broadcast period, the topology information storage unit 125 connects the first router and the switch to the edge and connects the switch and the second router to the edge. Can be stored.

The topology information storage unit 125 may store the type of the node and the connection information between the nodes until there are no more nodes to be examined for all nodes on the network.

3 is a diagram illustrating a method for searching for a neighbor router according to an embodiment of the present invention.

As shown, on the network, routers R1, R2, R3, R4, R5, and R6 are connected with the router R0 as the root node, and the switch SW1 is also connected to the router R0.

At this time, routers R1, R2, and R3 are directly connected to the router R0 as neighbor nodes, and routers R4, R5, and R6 are connected to the router R0 as neighbor nodes through a switch.

The neighbor node detection module 113 may directly detect neighbor node information on a routing protocol, and may detect both information of a directly connected router and information of a router connected through a switch.

In the present embodiment, the neighbor node detection module 113 may detect routers R1, R2, R3, R4, R5, and R6 as neighbor nodes of the root node R0.

For example, in the case of an OSPF backbone network, the neighbor node detection module 113 may directly detect neighbor router information using OSPF neighbor (ospfNbrIpAddr) information on SNMP.

At this time, since there is no switch in the OSPF neighbor information, the switch SW1 is not detected as a neighbor node of the router RO, and the routers R4, R5, and R6 may be detected as neighbor nodes of the router R0.

4 is a diagram illustrating a method of searching for a neighbor switch according to an embodiment of the present invention.

The interface analysis module 115 may analyze a connection type between nodes, and may determine whether the connection method between the first router and the second router is a point-to-point or broadcast method.

As shown, routers R0, R1, R2, and R3 are point-to-point, and routers R0, R4, R5, R6, and switch SW1 are connected in a broadcast manner.

The interface analysis module 115 may detect the addresses of the devices connected to the broadcast interval. For example, in the case of an OSPF backbone network, the interface analysis module 115 may obtain an IP address corresponding to a physical address on SNMP.

When there is a management IP in the switch, the interface analysis module 115 may detect addresses of devices such as a host PC and a router, including the presence of a switch not detected by the neighbor node detection module 113.

The interface analysis module 115 may extract the switch candidate by comparing the addresses of the devices connected to the broadcast interval with the addresses of the neighbor routers detected by the neighbor node detection module 113.

As shown, the neighbor routers of R0 detected by the neighbor node detection module 113 are R1, R2, R3, R4, R5, R6, and the devices connected to the router R0 in the broadcast interval are R4, R5, R6, SW1 is a switch candidate because it is SW1.

In addition, the switch detection module (! 17) may check whether SW1 is a switch, and the detailed description thereof will be omitted.

5 is a flowchart of a method for searching an entire topology according to an embodiment of the present invention.

As shown, the topology detection system 100 detects the entire network topology by finding nodes connected to the surroundings at any node and making a connection relationship between them, and moving to the neighboring nodes to find the nodes connected to the neighboring nodes. Done.

The topology detection system 100 may select an unvisited node first router and collect neighbor node information from an arbitrary node (S100, S110, S120, and S130).

 The topology detection system 100 may detect router information directly connected to the node to be investigated in a routing protocol through a routing protocol. When the neighboring routers are connected through at least one switch, the topology detection system 100 may detect only information of routers other than the switch. have.

The topology detection system 100 may extract the switch candidate when the connection period between the nodes is the broadcast period, and the detailed description thereof will be omitted since it has been described above.

The topology detection system 100 may check whether the switch is actually present by checking whether the data link layer is supported on the OSI 7 layer and whether IP packet forwarding is performed on the switch candidate device (S140 and S160). . Since the details of the switch detection have already been described above, they will be omitted.

When the connection between the first router and the second router is point-to-point, the topology detection system 100 may connect the first router and the second router to the edge (S150).

When the connection between the first router and the second router exists in the broadcast period, the topology detection system 100 may connect the first router and the switch at the edge and connect the switch and the second router at the edge ( S170).

The topology detection system 100 may configure a topology in which neighboring nodes are added in the previously obtained topology, and may change a property to a completed node in the sense that the necessary information has been collected for the first router. S180.

The topology detection system 100 may repeat the neighbor node survey around the second router as described above as an unvisted node for the second router added as the neighbor node.

The topology detection system 100 may finish the topology configuration when there are no more unvisited nodes for all nodes on the network (S190).

In addition, the storage medium according to the embodiment of the present invention is a storage medium that records a program for executing the above-described topology detection method.

What has been described above is only an embodiment of the present invention, and the scope of the present invention is not limited thereto, and various modifications can be made to those skilled in the art. For example, the servers constituting the topology detection system and the modules constituting each server may be additionally configured or merged according to their function. In addition, the topology detection method according to an embodiment of the present invention can be configured to change the order of course. The scope of the present invention will include all the technical elements recognized as the claims described below and equivalents thereof.

1 is a diagram illustrating a network topology detection system connected to a network according to an embodiment of the present invention.

2 is a detailed configuration diagram of a topology detection server and a topology information database according to an embodiment of the present invention.

3 is a diagram illustrating a method for searching for a neighbor router according to an embodiment of the present invention.

4 is a diagram illustrating a method of searching for a neighbor switch according to an embodiment of the present invention.

5 is a method flow diagram for retrieving the entire topology configuration in accordance with an embodiment of the present invention.

Claims (15)

In a topology detection system, Detects a network topology by detecting a second router, which is a neighboring router of the first router, and a switch based on whether a data link layer is supported or whether IP packet forwarding is performed when an interface type between nodes is a broadcast interval. server; And Contains a topology information database that stores network topology information. Topology detection system The method of claim 1, The topology detection server, A neighbor node detection module for detecting a router connected to the neighbor directly or through a switch; An interface analysis module that analyzes an interface type between nodes and detects switch candidate equipment that is not detected by a router connected to a neighbor by the neighbor node detector as equipment connected in a broadcast period; And A switch candidate device, the switch candidate device comprising a switch detection module for detecting a device that supports the data link layer or does not perform IP packet forwarding. Topology detection system. The method of claim 2, When the connection between the first router and the second router is a point-to-point, the first router and the second router are connected to the edge, and when the connection between the first router and the second router is a broadcast interval, the first Further comprising a topology configuration module for connecting the router and the switch at the edge and connecting the switch and the second router at the edge Topology detection system. The method of claim 3, The interface analysis module, The device detected by the device connected to the broadcast interval, but not detected by the router connected to the neighbor by the neighbor node detector as a switch candidate. Topology detection system. The method of claim 4, wherein The neighbor node detection module Neighbor router information is detected using OSPF neighbor information (ospfNbrIpAddr). Topology detection system. The method of claim 5, The interface analysis module, Detecting the addresses of devices connected to the first router and the broadcast interval through the IP address (ipNetToMediaNetAddress) information corresponding to the physical address in SNMP Topology detection system. The method of claim 6, The switch detection module determines whether the switch supports the data link layer when the lower two bits of the sysService are 1 on SNMP, or the switch that does not support IP packet forwarding when the ipForwarding value is 0. Topology detection system. In the topology detection method, a) detecting a second router that is a immediately neighboring router of the first router; b) determining the interface type between neighbor nodes and detecting a switch candidate in the broadcast period; And c) checking whether the switch is based on whether the data link layer is supported or whether IP packet forwarding is performed. Topology detection method. The method of claim 8, Step a) Detecting routers connected to neighbors directly or through a switch Topology detection method. The method of claim 9, Step b) is b-1) determining an interface type between nodes; And b-2) in the case of a broadcast period, detecting a device that is connected by a broadcast method and not detected by a router connected to a neighbor in step a) as a switch candidate device; Topology detection method. The method of claim 10, d) if the connection between the first router and the second router is point to point, connecting the first router and the second router to the edge; e) if the connection between the first router and the second router is present in the broadcast interval, further comprising connecting the first router and the switch at the edge and connecting the switch and the second router at the edge; Topology detection method. The method of claim 9, Step a) is Detecting neighbor router information using OSPF neighbor information (ospfNbrIpAddr) Topology detection method. The method of claim 12, Step b), b-1) detecting the addresses of the devices connected to the first router and the broadcast interval through the IP address (ipNetToMediaNetAddress) information corresponding to the physical address on the SNMP; And b-2) comparing with the second router detected as the immediate neighbor router of the first router in step a); And b-3) detecting a device which is connected to the first router in a broadcast interval and is not detected by the second router as a switch candidate device; Topology detection method. The method of claim 13, Step c) is If the lower 2 bits of sysService are 1 in SNMP, it is determined as a switch that supports the data link layer. If the ipForwarding value is 0, it is determined as a switch that does not support IP packet forwarding. Topology detection method. A storage medium having recorded thereon a program for executing the method according to any one of claims 8 to 15.

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