JP2008205682A - Test device, method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a test device capable of verifying the operation of a network and a communication apparatus to be added to the network when the communication apparatus is added to the network. <P>SOLUTION: The test device includes: one or more physical interfaces for exchanging signals; a means for holding apparatus information to be used for generating the routing table of the respective existing communication apparatuses included in the network to be simulated; a means for holding connection information which indicates a connection state between the added communication apparatus to be tested and the existing communication apparatuses; a means for generating the routing table of each existing communication apparatus, based on the apparatus information and the connection information; a means for holding connection point information indicating the interface of the existing communication apparatus which corresponds to the physical interface; a means for generating link information to be transmitted by the physical interface, based on the connection point information, the apparatus information, and the connection information; and a means for updating the connection information, based on the link information to be received by the physical interface. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a network testing technique in which each communication device exchanges link information.

  In packet switching networks such as the Internet, communication devices that perform packet exchange processing such as routers that make up the network create routing tables by exchanging information indicating the connection status between communication devices, that is, link information, using various routing protocols. And a link for transferring the received packet is determined based on the routing table.

  A network operator providing a network adds a new communication device to the network or removes an existing communication device from the network in response to an increase or decrease in traffic flowing through the network or for renewal of a new communication device. It is necessary to do.

  When a new communication device is connected to an existing network, based on the link information received from the existing network, how the new communication device behaves, for example, what routing table the additional communication device creates, A test apparatus for examining how to perform packet exchange processing has been put into practical use (for example, see Non-Patent Document 1). These test devices send a link status advertisement message for notifying link information to the outside by a predetermined routing protocol based on information indicating the configuration of an existing network and information indicating a connection point with a newly added communication device. It has a function to do.

[Online], SPIRENT COMMUNICATIONS, [Search January 18, 2007], Internet <URL: http: // www. spirentcom. com / documents / 4239. pdf>

  For example, as shown in FIG. 5, consider a case where routers 21 to 24 as new communication devices are added to the network 3. In FIG. 5, reference numerals 31 to 33 represent routers connected to a new communication device among existing routers constituting the network 3, and reference numerals 41 to 46 represent connection links between the routers. .

  Since all of the routers 21 to 24 cannot be connected to the network at the same time, normally, new communication devices are added one by one. For example, the router 21 and the existing router 31 are connected by the link 41, then the router 22 and the existing router 32 are connected by the link 42, then the router 23 and the router 21 are connected by the link 43, and then the router 23 and the router 22 is connected by the link 44, the router 24 and the router 22 are then connected by the link 45, and finally, the router 24 and the existing router 33 are connected by the link 46, so that the routers 21 to 24 are added to the network 3. Is completed.

  By connecting the router 21 to the existing router 31, the router 21 receives the link status advertisement message from the existing router 31. At the same time, the router 21 transmits a link status advertisement message to the existing router 31. Thus, the existing router 31 notifies the other existing routers in the network 3 that the router 21 is connected by a link status advertisement message. Therefore, the routing table of the existing router in the network 3 and the link state advertisement message to be transmitted change. Subsequently, by connecting the router 22 to the existing router 32, the router 22 receives a link status advertisement message from the existing router 32, and this link status advertisement message reflects a change caused by the connection of the router 21. It becomes. Moreover, the routing table of each existing router in the network 3 and the router 21 is further changed by the link state advertisement message transmitted by the router 22. In the subsequent connection between the routers 23 and 21 and the connection between the routers 22 and 23, these configuration changes are transmitted to the network 3, whereby the link status advertisement message transmitted / received between the network 3 and the added router. And the routing tables of the existing router and the added router in the network 3 also change.

  However, since the conventional test apparatus only transmits the link state advertisement message fixedly based on the network configuration information inputted in advance, the behavior of the additional communication apparatus when these communication apparatuses are added sequentially. Cannot be verified. In addition, if there is an error in the setting of the added communication device, this error is transmitted to the network 3 by the link status advertisement message and may affect the network 3, but this is given to the network 3 by adding the communication device. The impact cannot be verified.

  Therefore, an object of the present invention is to provide a test apparatus and method that can solve the above-described problems and can verify the operation of the network and the added communication apparatus when the communication apparatus is added to the network. It is another object of the present invention to provide a program that causes a computer to function as the test apparatus.

According to the test apparatus of the present invention,
One or more physical interfaces for transmitting and receiving signals, means for holding device information used to create a routing table for each existing communication device included in the simulation target network, additional communication device to be tested, and existing communication device Means for holding connection information indicating a connection state, means for generating a routing table of each existing communication device based on the device information and connection information, and connection point information indicating an interface of the existing communication device corresponding to the physical interface And means for generating link information to be transmitted to the physical interface based on the connection point information, device information and connection information, and means for updating the connection information based on the link information received by the physical interface. Features.

According to another embodiment of the test apparatus of the present invention,
When the destination of the received signal is an additional communication device, a physical interface used for signal transfer to the additional communication device is obtained based on the routing table of each existing communication device, and the received signal is sent to the obtained physical interface. It is also preferable to have a means for transmitting.

According to another embodiment of the communication device of the present invention,
When receiving a test signal whose destination is an existing communication device, it is also preferable to provide a means for generating a response signal according to the test content and transmitting the generated response signal to the physical interface that has received the test signal. .

Furthermore, according to another embodiment of the communication device of the present invention,
The connection point information has a tag value corresponding to the interface of the existing communication device, and based on the tag value of the received signal, recognizes the existing communication device that receives the received signal, and the transmission signal transmits the transmission signal. It is also preferable to include means for assigning a tag value corresponding to the interface of the existing communication device to be transmitted from the physical interface corresponding to the interface of the existing communication device.

According to the program of the present invention,
A computer is caused to function as the test apparatus.

According to the test method of the present invention,
The test apparatus according to claim 4 and each additional communication apparatus are connected to a port of an exchange apparatus that exchanges signals based on a tag value, and an existing port connected to the additional communication apparatus is connected to a connection port with the additional communication apparatus. By setting the switching device so that the tag value signal corresponding to the interface of the communication device is exchanged, additional communication can be performed with fewer physical interfaces than the number of connection links between the network to be simulated and the additional communication device. It is characterized by testing the device.

  By updating the connection information based on the link information received by the physical interface, the link information transmitted by the physical interface changes according to the connection state of the additional communication device, and thus the behavior of the additional communication device and the simulation target network is changed. It can be verified accurately.

  Also, when a signal addressed to the additional communication device is received, a transfer process is performed based on the routing table of each existing communication device that is dynamically changed according to the connection of the additional communication device, and a test addressed to the existing communication device from the additional communication device. When a signal is received, it is possible to verify the actual data communication status by transmitting a response signal corresponding to the test content based on the routing table and connection information.

  Further, by using the tag value, it is possible to test the additional communication device with a smaller number of physical interfaces than the number of connection links between the simulation target network and the additional communication device.

  BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out the present invention will be described below in detail with reference to the drawings. In the following explanation, the communication device included in the network simulated by the test device is an existing router, the communication device to be tested, that is, the newly added communication device is an additional router, and the communication that connects the additional router among the existing routers Each device is referred to as a connection point router.

  FIG. 1 is a functional block diagram of a test apparatus 1 according to the present invention. According to FIG. 1, the test apparatus 1 includes a network information database 10, a message generation unit 11, a message processing unit 12, an exchange processing unit 13, a test packet generation unit 14, and one or more interfaces 15-1. 15-N. Note that the interfaces 15-1 to 15-N are simply referred to as the interface 15 when it is not necessary to distinguish them.

  The interface 15 has a function of transmitting and receiving signals in accordance with various communication standards such as 1000BASE-T.

  The network information database 10 is a database having information indicating the configuration of an existing network to be simulated, stored in a storage unit such as a memory or a hard disk of the test apparatus 1, and the apparatus information database 101, the connection information database 102, and the routing information database 103. And a connection point information database 104. Here, the device information database 101 is a database of device information set for each existing router in the simulation target network. The device information is, for example, a cost value for a link, and each existing router is a routing table. Information used to create The connection information database 102 is information indicating the connection status of the existing router and the additional router, that is, a database indicating the connection status of the network constituted by the existing router and the additional router. At the start of the test, only the connection information between the existing routers is included, and these are input to the test apparatus 1 based on the simulation target network. Information about the connection of the additional router is added by connecting the additional router to the interface 15 as will be described later.

  The routing information database 103 is a routing table of each existing router generated based on the device information of each existing router indicated by the device information database 101 and the connection information indicated by the connection information database 102, and is generated by the message processing unit 12. .

  The connection point information database 104 is information for specifying the interface 15 corresponding to the interface of the connection point router. Specifically, as shown in FIG. 2, when the test apparatus 1 is operated as the network 3 of FIG. 5, the interface 15-1 corresponds to one of the interfaces of the connection point router 31, and the interface 15-2 Corresponds to one of the interfaces of the connection point router 32, and the connection information database 102 indicates that the interface 15-3 corresponds to one of the interfaces of the connection point router 33.

  The message generator 11 generates link information to be transmitted to the interface 15 based on the connection point information, device information, and connection information, and the interface 15 transmits a link state advertisement message including the link information to the outside. For example, in the test configuration of FIG. 2 simulating the configuration of FIG. 5, the message generator 11 obtains a link state advertisement message to be transmitted by the interface 15-1 corresponding to one interface of the connection point router 31, and 15-1 is transmitted.

  When the additional router is connected to the interface 15, the message processing unit 12 updates the connection information database 102 from the link state advertisement message received by the interface 15 from the additional router, and further, the device information and connection of the device information database 101. The routing information database 103 is updated based on the connection information in the information database 102. For example, in the test shown in FIG. 2, when the additional router 21 is first connected to the interface 15-1, the new router 21 is connected to the connection point router 31 based on the link status advertisement message received from the additional router 21. Then, the connection between the connection point router 31 and the additional router 21 is added to the connection information database 102, and the necessary routing table is changed to the routing information database 103.

  The exchange processing unit 13 analyzes a packet received from the additional router, and performs necessary exchange processing when the transmission destination is the additional router. Specifically, the interface of the connection point router through which the packet is transmitted is specified from the packet transmission destination address and the routing information database 103, and the received packet is transmitted to the interface 15 corresponding thereto. Further, when the transmission destination is an existing router, it is determined from the routing information database 103 whether there is a problem in routing to the existing router, that is, whether the received packet reaches the existing router. The result is displayed on a display device (not shown).

  When the test packet generation unit 14 receives a test packet, for example, an ICMP (Internet Control Message Protocol) packet from the additional router, the test packet generation unit 14 generates a necessary response packet based on the routing information database 103 and the test content, The response packet is transmitted to the received interface 15. Specifically, if the ICMP packet is an echo request, so-called Ping, and the destination address is an existing router, an echo response is generated. When the transmission destination is an additional router, the ICMP packet is simply transferred by the exchange processing unit 13.

  In addition, the number of hops from the interface 15 that has received the ICMP packet to the existing router that is the transmission destination, or the number of hops to the connection point router that is routed to transfer to the additional router that is the transmission destination is displayed in the routing information database. If the TTL (Time to Live) of the ICMP packet becomes 0 before reaching the existing router or connection point router of the transmission destination from this hop count, for example, the packet generated by the Traceroute command If there is, a discard notification is transmitted to the additional router that is the source of the ICMP packet.

  As described above, the connection information database 102 is updated based on the link status advertisement message received through the interface 15 and the connection point information. The link state advertisement message generated by the message generation unit 11 due to this update changes according to the connection state of the additional router, and thus the behavior of the additional router and the original network can be verified accurately.

  Further, when the destination of the received packet from the additional router is the additional router, forwarding processing is performed based on the routing information database 103 that is dynamically changed according to the connection of the additional router, and the ICMP packet is transferred from the additional router. When a representative test packet is received, by transmitting a response packet based on the routing information database 103, it is possible to verify the actual data communication status.

  Further, based on the routing table of each existing router held in the routing information database 103, not only the reachability of the received packet but also the reachability between the existing routers when the packet addressed to the existing router is received from the additional router. Can also be verified.

  In the above-described embodiment, the test apparatus 1 needs to mount the same number of interfaces 15 as the number of connection points with the network 3. FIG. 3 shows a block diagram of another embodiment of the test apparatus 1 according to the present invention for eliminating this inconvenience. In FIG. 3, a tag processing unit 16 is provided between the interface 15 in the configuration of FIG. 1 and the message generation unit 11, message processing unit 12, exchange processing unit 13, and test packet generation unit 14. Further, in the present embodiment, the connection point information database 104 has tag value information corresponding to the interface of the connection point router in addition to the interface 15 corresponding to the interface of the connection point router. Here, the tag value is, for example, a VLAN tag defined by IEEE802.1Q, and this tag value is input to the test apparatus 1 in advance based on the test configuration.

  In the present embodiment, a single interface 15 can be associated with interfaces of a plurality of connection point routers, but the correspondence between the connection point router interfaces and tag values is 1: 1. In the following, description will be made using a form in which only one interface 15 is mounted, but it is naturally applicable to a plurality of interfaces 15.

  When the existing router has a signal to be transmitted to the outside, the tag processing unit 16 assigns a tag value corresponding to the interface of the existing router to which the transmission signal is applied to the transmission signal based on the connection point information. Actual transmission from the interface 15. For the signal received from the interface 15, the existing router that should receive this received signal and its interface are recognized based on the assigned tag value, and the message processing unit 11 together with information indicating this existing router and its interface. Alternatively, the received packet is output to the exchange processing unit 13.

  FIG. 4 is a diagram illustrating a test method according to the present invention when the test apparatus 1 is operated as the network 3 of FIG. As shown in FIG. 4, the additional routers 21, 22, 24 and the test apparatus 1 are connected to each port of the VLAN hub 5. For the test apparatus 1, the value of the VLAN tag used for the signal transmitted by the interface corresponding to the interface 15 of the connection point router 31 is set, and the additional router 21 receives the signal having the value of the VLAN tag. The VLAN hub 5 is configured to switch to the port of the connected VALN hub 5. Even if there is only one interface 15 of the test apparatus 1 by performing the same setting for the set of the connection point router 32 and the additional router 22 and the set of the connection point router 33 and the additional router 24, it is logical. A plurality of connection links can be constructed at the same time, and verification of a test when connecting at a plurality of points becomes possible.

  Note that the VLAN hub 5 is an example, and any switching device capable of exchanging signals or switching based on the tag value can be used in place of the VLAN hub 5.

  The test apparatus according to the present invention can be realized by a computer program that causes a computer to function as each unit in FIG. This computer program is stored in a computer-readable storage medium or can be distributed via a network. Furthermore, the present invention can be realized not only by hardware and software but also by a combination thereof.

It is a functional block diagram of the testing apparatus by this invention. It is a test block diagram by the testing apparatus by this invention. It is a block diagram of other embodiments of a testing device by the present invention. It is a test block diagram by other embodiment of the testing apparatus of this invention. It is a figure explaining addition of the communication apparatus to a network.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Test apparatus 10 Network information database 11 Message generation part 12 Message processing part 13 Exchange processing part 14 Test packet generation part 15, 15-1, 15-2, 15-3, 15-N interface 16 Tag processing part 101 Device information database 102 Connection information database 103 Routing information database 104 Connection point information database 21, 22, 23, 24 Router 3 Network 31, 32, 33 Existing router 41, 42, 43, 44, 45, 46 Link

Claims (6)

One or more physical interfaces to send and receive signals;
Means for holding device information used to create a routing table for each existing communication device included in the network to be simulated;
Means for holding connection information indicating a connection state of an additional communication device to be tested and an existing communication device;
Means for generating a routing table for each existing communication device based on device information and connection information;
Means for holding connection point information indicating an interface of an existing communication device corresponding to a physical interface;
Means for generating link information to be transmitted to a physical interface based on connection point information, device information and connection information;
Means for updating connection information based on link information received by the physical interface;
Test equipment equipped with.   When the destination of the received signal is an additional communication device, a physical interface used for signal transfer to the additional communication device is obtained based on the routing table of each existing communication device, and the received signal is sent to the obtained physical interface. The test apparatus according to claim 1, further comprising means for transmitting   2. A means for generating a response signal according to a test content and transmitting the generated response signal to a physical interface that has received the test signal when receiving a test signal whose destination is an existing communication device. Or the test apparatus of 2. The connection point information has a tag value corresponding to the interface of the existing communication device,
Based on the tag value of the received signal, the existing communication device that receives the received signal is recognized, and the tag value corresponding to the interface of the existing communication device to which the transmitted signal is transmitted is assigned to the transmission signal, Means for transmitting from a physical interface corresponding to the interface of the device;
The test apparatus according to any one of claims 1 to 3, further comprising:   A program for causing a computer to function as the test apparatus according to any one of claims 1 to 4. The test apparatus according to claim 4 and each additional communication apparatus are connected to a port of an exchange apparatus that exchanges signals based on tag values,
In the connection port with the additional communication device, by setting the exchange device so that the tag value signal corresponding to the interface of the existing communication device connected to the additional communication device is exchanged,
A method of testing an additional communication device with a smaller number of physical interfaces than the number of connection links between the simulation target network and the additional communication device.

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