KR100694204B1 - Device and method for testing loopback in WAN system - Google Patents

Abstract

A loopback test apparatus in a wide area network system according to the present invention comprises: an loopback test apparatus in a wide area network system, the loopback test apparatus comprising: an identification information processor for generating / changing identification information in a loopback control field of packet data; A transmission count controller configured to set a transmission count or time of packet data to be transmitted for the loopback test; A transmission control unit for controlling transmission of packet data including a loopback control field to a destination; And a loopback control unit configured to detect an error portion of a network system through a reception rate of packet data received by looping back, wherein the five representative loopbacks are error detection methods used in a wide area network system using a dedicated line. It allows you to check modes at once.

Wide Area Network (WAN), Loopback Test.

Description

Device and method for testing loopback in wide area network system

Figure 1a is a functional block diagram showing the configuration of a line interface card of a general wide area network communication system,

FIG. 1B is a functional block diagram illustrating a loopback test of a local network in a general wide area network system according to FIG. 1A.

1C is a functional block diagram illustrating a loopback test of a remote line interface in a general wide area network system according to FIG. 1A.

FIG. 1D is a functional block diagram illustrating a loopback test of a remote network payload in the general wide area network system according to FIG. 1A;

FIG. 1E is a functional block diagram illustrating a loopback test of a local line interface in a general wide area network system according to FIG. 1A;

FIG. 1F is a functional block diagram illustrating a loopback test of a local network payload in a general wide area network system according to FIG. 1A.

2 is a functional block diagram showing the configuration of a loopback test apparatus in a wide area network system according to an embodiment of the present invention;

3 is a functional block diagram illustrating a configuration of a loopback control unit among loopback test apparatuses in the wide area network system according to FIG. 2;

4 is a flowchart illustrating a loopback test method in a wide area network system according to an embodiment of the present invention;

5 is a flowchart showing the detailed steps of the packet data transmission step (S1) of the loopback test method in the wide area network system according to FIG.

FIG. 6 is a flowchart illustrating detailed steps of an error checking step S2 of a loopback test method in the wide area network system according to FIG. 4;

7 is a flowchart illustrating a method of processing received packet data in a loopback test method in a wide area network system according to an embodiment of the present invention;

8 is a diagram illustrating a loopback control field and identification information in a loopback test apparatus and method in the wide area network system according to FIGS. 2 to 7.

<Explanation of symbols for the main parts of the drawings>

11: line interface 12: framer

100: loopback control unit 101: identification information processing unit

102: transmission number control unit 103: transmission control unit

104: error detection unit

The present invention relates to a loopback test apparatus and method for verifying internal and external lines for defects and defects in data communication equipment. The present invention relates to a loopback test apparatus and method in a wide area network system that can more conveniently verify the state of a line and a configuration by using a tool, a command, and a structure.

In general, a communication system includes a local area network (LAN) system for short-range communications and a wide area network (WAN) system for telecommunications.

Among them, wide area network (WAN) system is a local area network (LAN) or metropolitan area network that is distributed in a wide area using communication line services such as leased lines, packet switching networks, and integrated information network (ISDN) provided by public service providers. A large scale communication network formed by interconnecting (MAN).

While the premises information network performs high quality transmission at a relatively narrow range at high speed, the wide area network has a feature that can serve a large area although the communication speed and transmission quality are rather poor. Therefore, when digitalization, high speed, and wide bandwidth are achieved, the transmission speed can be increased from 64 kbps of ISDN to 156 Mbps of ATM (asynchronous transfer mode) dedicated line.

Such a wide area network system includes a line interface card for connecting the system to the system at the end.

The line interface card of the conventional wide area network system is a line interface unit (Line Interface Unit 11) for converting an electrical signal from an external line into a data frame of DS (Digital Signal) -n standard as shown in FIG. 1A. 11 and framer 12;

High-level Data Link Control (HDLC) for channelizing the frames output from the line interface 11 and the framer 12;

A Field Programmable Gate Array (FPGA) connected to the HDLC and connected to a network processor for network processing; And

And a data forwarding processing unit connected to the FPGA to perform a router function.

The network wide area network system is connected to the line interface card through a dedicated line such as T1, E1, or T3, and performs data transmission through the dedicated line.

In addition, the wide area network system has been recognized as one of the most important issues due to the compatibility between each other equipment, configuration, and long-distance network, synchronization between each other and the identification of abnormalities on the data line.

Because of this, each device has a unique method of verifying the error of the device, which is called the loopback test. At this time, the loopback test is a test signal sent from the telephone system to a network destination by using a loopback signal, and the signal is returned to the original signal source as the received signal. The returned signal can help diagnose the problem. Sending loopback signals one at a time to devices in each telephone system is a technique to isolate the problem (loopback can be compared to a ping utility that allows you to send messages to a host computer on the Internet.) Tells you whether the host computer is available and how long it takes to respond to a signal).

Therefore, a general wide area network system must support various loopback modes to test long distance equipment locally and remotely.

This loopback mode consists of verifying each test item to a specific part of each device. This enables the current status and error part of the device to be detected by the success or failure of a specific loopback. In order to find out whether there is an error in the configuration of the network equipment, each command should be used. If the transmitted frame is received after loopback, the error rate or error may be caused by the success or failure of reception. This is because the error count is checked.

The loopback test mode of such a general wide area network system includes a local network shown in FIG. 1B, a remote line interface shown in FIG. 1C, a remote network payload shown in FIG. 1D, a local line interface shown in FIG. 1E, and FIG. 1F. There are five major divisions, such as the loopback test of the local network payload shown in Figure 5. The reason for the five separate commands is that for each transmitted frame, each received frame is received at which loopback. It is difficult to judge whether or not it is, so that it is easy to distinguish.

This separate loopback has a disadvantage in that it is difficult to find out how to verify the network condition over long distances and the results after verification.

That is, for this reason, most of the wide area network interfaces or the loopback mode of the DS-n series have the following commands.

Prompt> Enable ports <portlist> [t1 | e1 | t3] Loopback [local | network line | network payload],

Prompt> Enable ports <portlist> [t1 | e1 | t3] Loopback [remote line | remote payload]

However, in the conventional wide area network system, the loopback test exists for each type of loopback, and since this type needs to be performed for a specific time, it takes time and effort to execute a specific command for a specific time. In addition to the need for a procedure to collect the results in order to report the results, each loopback has a cumbersome problem that needs to be handled in each case because each loopback cannot determine the error condition at once.

Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to perform a command according to a test case each time a user wants to know a current state and an error occurrence point of a network equipment. The present invention provides a loopback test apparatus and method in a wide area network system that can easily check and detect each state of a network through a single command.

According to an aspect of a loopback test apparatus in a wide area network system according to the present invention for achieving the above object, an identification information processor for generating / changing identification information in a loopback control field of packet data; A transmission count controller configured to set a transmission count or time of packet data to be transmitted for the loopback test; A transmission control unit for controlling transmission of packet data including a loopback control field to a destination; And a loopback control unit configured to detect an error portion of the network system through a reception rate of packet data received by being looped back.

And a result providing unit for storing the reception rate of the system detected by the error detector in a database and displaying the received rate to a user.

It also includes a line interface and a framer for inspecting the loopback control field of the received packet data, and looping back the received packet data when the loopback control field includes a setting value for testing itself.

On the other hand, according to an aspect of a loopback test method in a wide area network system according to the present invention, the loopback control unit, the loopback control unit setting / changing identification information in the control field of the packet data for any loopback test; Controlling the loopback control unit to transmit packet data including a loopback control field to a destination; And if it is determined whether the loopback control unit has transmitted all packet data for the loopback test for a predetermined time or number of times, and then all of the packet data is transmitted for a predetermined time or number of times, proceed to the loopback control field setting / change step, If all are not transmitted, proceeding to the packet data transmission step; And the loopback control unit checking whether the network system has failed through the reception rate of the packet data to be looped back.

delete

The failure checking step may include determining whether packet data transmitted for any loopback test has been received; And when the packet data is received in the packet data receiving step, calculating an error rate of the network system based on a reception rate of the received packet data for a predetermined time or number of times.

On the other hand, when receiving the packet data in the loopback test method in the wide area network system according to the present invention, according to one aspect of the processing method, if receiving the packet data detects the loopback control field to determine whether the identification information indicates itself; And if the identification information of the loopback control field indicates itself in the determining step, looping back the received packet data.

In this case, if the identification information of the loopback control field does not indicate itself in the determination step, controlling to transmit to the destination of the packet data.

Hereinafter, a loopback test apparatus and method in a wide area network system according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 is a functional block diagram of a loopback test apparatus in a wide area network system according to an embodiment of the present invention. In the wide area network system according to an embodiment of the present invention, the loopback test apparatus includes a line interface 11 and a framer 12. , And a loopback control unit 100.

The framer 12 is a module for processing a loopback and controls the line interface 11. The framer 12 explicitly distinguishes the overlapping portions and manages the mode of the loopback as a whole.

The line interface 11 is connected to the framer 12 and to the external line interface 11, and performs a loopback under the control of the framer 12.

In this case, the line interface 11 and the framer 12 perform a basic function of converting and transmitting a data frame of a digital signal standard from the received electrical signal, and channelizing the frames not shown in the figure. HDLC (High-level Data Link Control). And a loopback register for storing identification information of the loopback control field included in the packet data.

In addition, the HDLC is connected to a field programmable gate array (FPGA) for connection with a network processor for network processing, which is not shown in the figure, and the FPGA is connected to a forwarding part that must actually process a network packet. have.

In addition, the loopback control unit 100 generates / transforms a loopback control field in the packet data according to the loopback test item and transmits the loopback control field, and then checks whether the network system fails through the reception rate of the packet data to be looped back. As shown in FIG. 3, the identification information processing unit 101 includes a transmission number control unit 102, a transmission control unit 103, and an error detection unit 104.

The identification information processing unit 101 of the loopback control unit 100 serves to generate / change identification information in the loopback control field of the packet data. At this time, the loopback control field (LCF) as shown in Figure 8 includes three bits of identification information, the identification information does not perform a loopback "000"; "001" for loopback testing of the local network; "010" for loopback test of the local line interface; "011" for loopback test of local network payload; "100" for a loopback test of the remote line interface 11; "101" for loopback testing of remote network payload; And "110" and "111" for further loopback testing later.

In addition, the transmission number control unit 102 of the loopback control unit 100 serves to set the transmission number or time of packet data to be transmitted for the loopback test. In general, a packet transmits 20 loop data in one loopback test.

In addition, the transmission control unit 103 of the loopback control unit 100 serves to control transmission of packet data including a loopback control field to a destination.

In addition, the error detector 104 of the loopback control unit 100 detects an error portion of the network system through a reception rate of packet data received by looping back.

On the other hand, the loopback control unit 100 includes a result providing unit that stores the reception rate of the system detected through the error detector 104 in a database (not shown) and displays it to the user.

Next, an operation process of the loopback test apparatus in the wide area network system having the above configuration will be described.

The loopback test is to perform a loopback test of the local network, the local line interface 11, the local network payload, the remote line interface, and the remote network payload. Among these, the loopback test of the remote line interface will be described. .

First, the identification information processing unit 101 of the loopback control unit 100 generates / modifies identification information in the loopback control field of the packet data. At this time, the identification information processing unit 101 sets the identification information of the loopback control field to "100".

Then, the framer 12 generates packet data including a loopback control field in which the identification information is set to "100" and transmits the packet data to the destination through the control of the transmission control unit 103 of the loopback control unit 100. In this case, the packet data generated by the framer 12 is generally generated by the network processor of the network equipment and transmitted to the framer 12. The destination is the destination of the packet data regardless of the loopback control field. It means an address.

At this time, the transmission number control unit 102 of the loopback control unit 100 sets the transmission number or time of packet data to be transmitted for the loopback test. That is, the packet data including the loopback control field is transmitted 20 times for one type of loopback test.

Thereafter, the error detection unit 104 of the loopback control unit 100 detects an error portion of the network system through a reception rate of packet data received by looping back. In this case, the error detector 104 determines whether the packet data is transmitted by the local (self) by checking that the data is transmitted by itself through the source address information and the destination address information, and determines whether the packet data is transmitted by the local (self). By confirming that the identification information is "100", it can be confirmed that the packet data transmitted from the local area is normally received after being looped back through the remote line interface 11.

At this time, the above-described operation process is performed by the set number or time of transmission of the packet data. Here, since the packet data transmission is set to 20 times, if the packet data transmission exceeds 20 times, the identification information processing unit 101 of the loopback control unit 100 performs a loopback test of the remote network payload. In order to do this, the identification information of the loopback control field is set to "101". At this time, the identification information of the loopback control field is "000" which does not perform loopback; "001" for loopback testing of the local network; "010" for loopback test of the local line interface; "011" for loopback test of local network payload; "100" for loopback test of the remote line interface; "101" for loopback testing of remote network payload; And " 110 " and " 111 " for further loopback testing later, the loopback test can proceed in any order.

Thereafter, the above process is repeated, and five necessary loopback tests are performed.

Meanwhile, the loopback control unit 100 may store the reception rate of the packet data detected through the error detector 104 in a database and display the received rate to the user. That is, the error detection unit 104 of the loopback control unit 100 sets the identification information of the loopback control field to "101" for the loopback test, and then packet data transmitted for the set number of times (20 times) is looped back and received. The reception rate of the packet data determines whether an error occurs in the device for looping back.

If the line interface 11 and the framer 12 receive packet data from an external device, the identification information of the loopback control field of the packet data is detected and the identification information is used to test itself. Then loop back the received packet data. At this time, the line interface 11 and the framer 12 compare the identification information in the loopback control field of the packet data received from the external device with the information in the loopback control field stored in the loopback register to determine whether the loopback test device is itself. It can be determined whether or not.

On the other hand, when performing the loopback test of the local line interface and the loopback test of the local network payload, the identification information processing unit 101 of the loopback control unit 100 generates identification information in the loopback control field of the packet data. Change At this time, the identification information processing unit 101 sets the identification information of the loopback control field to "010" or "011". At this time, the loopback test of the remote line interface 11 and the loopback test of the remote network payload are performed to collect packet data from an external device so that the own line interface 11 and the framer 12 can determine whether there is no problem. After receiving, loop back and transmit.

Then, the framer 12 generates packet data including a loopback control field in which the identification information is set to "010" or "011", and then controls the transmission control unit 103 of the loopback control unit 100. Send to the destination. At this time, the packet data including the identification information "010", or "011" in the loopback control field transmitted from the framer 12 generates packet data for loopback test from the framer 12 at the remote location to generate the local data. Command data to be transmitted to the framer 12 or the line interface 11 of FIG. That is, the framer 12 receiving the packet data including the identification information "010" or "011" in the loopback control field includes: "100" for a loopback test of a local line interface at a remote location; The identification information is set to "101" for the loopback test of the local network payload, and then transmitted locally.

Thereafter, the framer 12 receives packet data having identification information set to "100" or "101" in the loopback control field from the framer 12 of the remote location.

Then, the error detector 104 of the loopback control unit 100 detects an error portion of the network system through the reception rate of the received packet data. At this time, the error detecting unit 104 confirms that the data is transmitted from the remote location through the source address information and the destination address information, and when the loopback control field of the received packet data is detected, the identification information of the loopback control field is “100”. "I can see that. Therefore, the packet data transmitted from the remote place is looped back and transmitted again to the remote place.

On the other hand, the transmission number control unit 102 of the loopback control unit 100 sets the number of transmission (20 times) of the packet data to be transmitted for the loopback test.

At this time, the above-described operation process is performed by the set number or time of transmission of the packet data. Here, since the packet data transmission is set to 20 times, if the packet data transmission exceeds 20 times, the identification information processing unit 101 of the loopback control unit 100 performs a loopback test of the local network payload. In order to change the identification information of the loopback control field, it is set.

If the five loopback tests are performed, the loopback control unit 100 stores the reception rate of the packet data detected through the error detector 104 in the database and displays the received rate to the user.

Next, the loopback test method in the wide area network system having the above configuration will be described with reference to FIG. 4.

First, the loopback control field is generated / converted in the packet data according to the loopback test item and then the packet data is transmitted (S1).

Hereinafter, a detailed operation process of the above-described first step S1 will be described in more detail with reference to FIG. 5.

First, identification information is set / changed in a control field of packet data for an arbitrary loopback test (S11).

Subsequently, packet data including the loopback control field is transmitted to the destination (S12).

Then, it is determined whether all the packet data for the loopback test has been transmitted for a set time or number of times, and if all the packet data is transmitted for the set time or number of times, the process proceeds to the loopback control field setting / changing step (S11), and the packet data. If none is transmitted, the packet data transmission step (S12) proceeds (S13).

On the other hand, the set time or number of packet data for any loopback test is set.

Thereafter, the network system checks whether the network system has failed through the reception rate of the packet data to be looped back (S2).

Hereinafter, a detailed operation process of the above-described second step S2 will be described in more detail with reference to FIG. 6.

First, the packet data transmitted for the random loopback test is received (S21).

Subsequently, an error rate of the network system is calculated based on the reception rate of the packet data received for the set time or number of times (S22).

Meanwhile, the loopback test method using the packet data received in the network system having the above configuration will be described with reference to FIG. 7.

First, upon receiving packet data from an external device, the loopback control field is detected to determine whether the identification information represents itself (S100).

Subsequently, if the identification information of the loopback control field indicates itself in the determination step (S100), the received packet data is looped back (S200).

On the other hand, if the identification information of the loopback control field does not indicate itself in the determination step (S100), and transmits to the destination of the packet data (S300).

Although the present invention has been described in detail only with respect to the specific embodiments described, it will be apparent to those skilled in the art that various changes and modifications can be made within the spirit of the present invention, and such modifications and modifications belong to the appended claims. .

As described above, according to the loopback test apparatus and method in the wide area network system according to the present invention, it is possible to inspect five representative loop back modes, which are error detection methods of the system used in the wide area network system using a dedicated line, at a time. It works.

Claims (13)

A loopback test apparatus in a wide area network system, An identification information processing unit for generating / changing identification information in a loopback control field of packet data; A transmission count controller configured to set a transmission count or time of packet data to be transmitted for the loopback test; A transmission control unit for controlling transmission of packet data including a loopback control field to a destination; And An apparatus for loopback testing in a wide area network system comprising a loopback control unit comprising an error detection unit for detecting an error portion of a network system through a reception rate of packet data received by being looped back. delete The method of claim 1, The loopback control unit, And a result providing unit for storing the reception ratio of the system detected by the error detector in a database and displaying the result to the user. The method of claim 1, The loopback control field may include three bits of identification information "001" for a loopback test of a local network. The method of claim 1, The identification information of the loopback control field may include “000” not performing loopback; "010" for loopback test of the local line interface; "011" for loopback test of local network payload; "100" for loopback test of the remote line interface; "101" for loopback testing of remote network payload; And "110" and "111" for further loopback testing later. The method of claim 1, The device, Loopback in a wide area network system including a line interface and a framer that examines the loopback control field of received packet data and, if the loopback control field contains a set value for testing itself, loops back the received packet data. Testing device. The method of claim 6, The line interface and the framer further comprises a loopback register for storing identification information of the loopback control field included in the packet data. A loopback test method in a wide area network system, The loopback control unit setting / changing identification information in a control field of packet data by the loopback control unit for any loopback test; Controlling the loopback control unit to transmit packet data including a loopback control field to a destination; And After determining whether the loopback control unit has transmitted all the packet data for the loopback test for a predetermined time or number of times, if all the packet data is transmitted for the predetermined time or number of times, the loopback control field setting / change step is carried out, If all are not transmitted, proceeding to the packet data transmission step; And A loopback test method in a wide area network system comprising the loopback control unit checking whether a network system has failed through a reception rate of packet data to be looped back. delete The method of claim 8, The packet data transmission step, And setting a set time or number of packet data for an arbitrary loopback test. The method of claim 8, The fault check step, Receiving packet data transmitted for any loopback test; And If the packet data is received in the packet data receiving step, calculating the error rate of the network system based on the reception rate of the packet data received for a predetermined time or number of times loop loop test method in a wide area network system. In a loopback test method in a telecommunication system, Detecting a loopback control field when the line interface and the framer receive the data to determine whether the identification information represents itself; And And if the identification information of the loopback control field indicates itself in the determining step, the line interface and the framer looping back the received packet data again. The method of claim 12, And if the identification information of the loopback control field does not indicate itself in the determining step, controlling the line interface and the framer to transmit the packet data to the destination of the packet data.

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