KR20100012227A - Apparatus for analyzing distributed network protocol call - Google Patents

Abstract

PURPOSE: An apparatus for an analyzing distributed network protocol call is provided to minimize function restriction of a physical layer by monitoring a DNP 3.0 protocol data unit between a master station and a slave station. CONSTITUTION: A communication interface unit(110) performs communications between a master station or a slave station by a serial communications standard according to a DNP(Distributed Network Protocol). A data generating unit(130) generates transmitted data for the slave station or the master station. A data analyzing unit(150) analyzes receiving data from the slave station or the master station. An operation state deciding unit(170) determines an operation state of the slave station or the master station.

Description

Distributed network protocol call analyzer {APPARATUS FOR ANALYZING DISTRIBUTED NETWORK PROTOCOL CALL}

The present invention relates to a distributed network protocol call analysis apparatus, and more specifically, to test the operation of the DNP 3.0 master and sub-stations, and physical layer when analyzing and monitoring the DNP 3.0 protocol data units transmitted and received between the main and sub-stations. It is a distributed network protocol call analysis device that can be easily applied to a general system by analyzing and monitoring by minimizing the functional limitation of the PC and connecting to a COM port of a PC using an RS-232 cable.

Distributed Network Protocol (DNP) is mainly used for remote monitoring. DNP is a standard communication protocol designed especially for utility industries such as electricity, power generation, and gas.DNP is an open communication protocol that applies the concept of master station and slave station in SCADA (Supervisory Control And Data Aquisition) system. Is one of.

In the SCADA system, the Control Center and RTU can be the main and sub stations, respectively, and the RTU and IED can be the main and sub stations, respectively. In particular, the DNP 3.0 protocol was defined to conform to the IEC 870-5, 101 and 103 standards, and was adopted by the IEEE as the recommended protocol for RTU (Remote Terminal Unit) and IED (Intelligent Electronic Device) communications. DNP 3.0 is used as a communication protocol between the main station and sub-stations. In particular, DNP 3.0 can be used when an event monitoring is performed and one main station is in an environment requiring control of one or more sub stations.

1 is a diagram illustrating message transmission and reception between a main station and a sub station using DNP 3.0.

The master station sends the DNP 3.0 request message to the secondary station, which sends the DNP 3.0 response message to the master station.

The response message can be generated in two ways.

First, for the request message received from the master station, the subsidiary generates a response message and sends it to the master station.

Second, even if a request message is not received from the master station, when the event occurs due to a change in state of the master station, the secondary station voluntarily generates a response message and sends it to the master station.

The spontaneous response message is a message that transmits a change of state of the rich country to the master as soon as possible. When using the spontaneous response message, the subsidiary may send the state change to the main station more quickly than the main station detects the state change of the sub station through polling.

The hierarchical structure of DNP 3.0 consists of the Enhanced Performance Architecture (EPA), modified from the OSI seven-layer model. That is, the hierarchical structure of DNP 3.0 consists of an application layer, a data link layer, and a physical layer except for four layers of the presentation layer, the session layer, the transport layer, and the network layer of the OSI 7-layer model. The DNP 3.0 hierarchy consists of three layers: the application layer, the data link layer, and the physical layer. Particularly, communication using serial ports requires four roles: presentation layer, session layer, transport layer, and network layer. The reason for this is to shorten the message processing time and improve work efficiency between layers.

In addition, DNP 3.0 places a pseudo transport layer between the application layer and the data link layer to compensate for the shortcomings of the data link layer.

According to DNP 3.0, the transmitting side transmits a message to the receiving side using user data in an application layer, a virtual transport layer, a data link layer, and a physical layer in sequence.

The present invention is connected to any one of the main or sub-station according to DNP 3.0 to determine the operation state of the main or sub-station, or connected to both the main and sub-stations by analyzing and monitoring the protocol unit transmitted and received between the main and sub-stations An apparatus for easily monitoring the operating state of the.

An object of the present invention can test the operation of the DNP 3.0 master and sub-stations, minimize the physical layer functional constraints when analyzing and monitoring the DNP 3.0 protocol data units transmitted and received between the main and sub-stations, RS-232 The present invention provides a distributed network protocol call analysis device that can be easily applied to a general system by performing analysis and monitoring by connecting to a COM port of a PC using a cable.

In order to achieve the above technical problem, the present invention is a distributed network protocol call analysis apparatus for analyzing the operation of the master or sub-station according to the distributed network protocol, and using the serial communication standard in accordance with the distributed network protocol and the master station or the sub-station. A communication interface for performing communication, a data generating unit for generating transmission data to be transmitted to the master station or the sub-station, a data analyzer for analyzing the received data received from the master station or the sub-station, and the reception of the data analysis unit. Provided is a distributed network protocol call analysis apparatus including an operation state determination unit for determining the operation state of the master station or the sub-station based on the data analysis result.

In the distributed network protocol call analysis apparatus according to the present invention, the serial communication standard is preferably RS-232C.

In the distributed network protocol call analysis device according to the present invention, the distributed network protocol is preferably DNP 3.0.

In the distributed network protocol call analysis apparatus according to the present invention, the data generation unit generates at least one of a response message and an optional acknowledgment message for transmitting to the master station, or a request message and an optional acknowledgment message for transmitting to the secondary station. Generating at least one, and the data analyzing unit analyzes at least one of a request message and an optional acknowledgment message received from the master station or at least one of a response message and an optional acknowledgment message received from the secondary station; The state determination unit determines whether there is an abnormality in at least one of a request message and an optional acknowledgment message received from the master station or at least one of a response message and an optional acknowledgment message received from the sub-station. May be to determine whether the subsidiary station operates normally.

In the distributed network protocol call analysis apparatus according to the present invention, the response message for transmitting to the master station generated by the data generator is received from the first response message and the master station generated for the request message received from the master station. And a second response message generated irrespective of the request message, wherein the communication interface unit preferentially transmits the second response message to the master station when the first response message and the second response message are generated at the same time. It may be.

In the distributed network protocol call analysis apparatus according to the present invention, the response message for transmitting to the master station generated by the data generator is received from the first response message and the master station generated for the request message received from the master station. And a second response message generated irrespective of the request message, wherein the communication interface unit preferentially transmits the first response message to the master station when the first response message and the second response message are generated at the same time. It may be.

The distributed network protocol call analysis apparatus according to the present invention may further include an operation state output unit configured to output whether the main station or the sub station is normally operated according to a determination result of the operation state determination unit.

In addition, the present invention is a distributed network protocol call analysis device for analyzing the communication between the master station and the sub-station according to the distributed network protocol, the transmission and reception data transmitted and received between the master station and the sub-station using the serial communication standard according to the distributed network protocol. Operation status monitoring for monitoring the operation state of the master station or the sub-station based on the received communication interface unit, a data analysis unit for analyzing the transmission and reception data according to the distributed network protocol, and the results of the transmission and reception data analysis of the data analysis unit Provided is a distributed network protocol call analysis apparatus including a portion.

In the distributed network protocol call analysis apparatus according to the present invention, the serial communication standard is preferably RS-232C.

In the distributed network protocol call analysis apparatus according to the present invention, the communication interface unit includes a first RS-232C communication interface unit for receiving the transmission / reception data transmitted from the main station to the sub station, and from the sub station to the master station. It may include a second RS-232C communication interface for receiving the transmission and reception data transmitted.

In the distributed network protocol call analysis device according to the present invention, the distributed network protocol is preferably DNP 3.0.

In the distributed network protocol call analysis apparatus according to the present invention, the data analyzer analyzes the transmission / reception data including at least one of a request message and an optional acknowledgment message received from the master station or a response message received from the secondary station; Analyzing the transmission / reception data including at least one of an optional acknowledgment message, and the operation state monitoring unit includes at least one of a request message and an optional acknowledgment message received from the master station, or at least one of a response message and an optional acknowledgment message received from the secondary station. It may be to monitor the operation state of the master station or the sub-station by determining the presence of one or more abnormalities.

The distributed network protocol call analysis apparatus according to the present invention may further include a transmission / reception data output unit configured to output the transmission / reception data.

According to the present invention, the operation of the DNP 3.0 master and sub stations can be tested, and the functional constraints of the physical layer can be minimized when analyzing and monitoring the DNP 3.0 protocol data units transmitted and received between the main station and the sub stations, and RS-232. It is easy to apply to general system by analyzing and monitoring by connecting to COM port of PC using cable.

Hereinafter, embodiments of the distributed network protocol call analysis device of the present invention will be described in more detail with reference to the accompanying drawings.

2 is a diagram illustrating a usage environment of a distributed network protocol call analysis apparatus according to the present invention.

As shown, the distributed network protocol call analysis apparatus 100 of the present invention (DNP call analysis apparatus 100) is connected to at least one of the master station 200 and the sub-station 300.

When only one of the master station 200 and the secondary station 300 is connected, the distributed network protocol call analysis apparatus 100 may test the operation of the connected master station 200 or the secondary station 300.

In addition, when connected to both the main station 200 and the sub-station 300, the distributed network protocol call analysis apparatus 100 may monitor and analyze the DNP 3.0 protocol data unit transmitted and received between the main station 200 and the sub-station 300. have.

3 is a block diagram of a distributed network protocol call analysis apparatus according to an embodiment of the present invention.

3, the distributed network protocol call analysis apparatus 100 according to an embodiment of the present invention, the communication interface 110, the data generation unit 130, the data analysis unit 150, the operation It includes a state determination unit 170. In addition, the distributed network protocol call analysis apparatus 100 according to an embodiment of the present invention may further include an operation state output unit 190.

The communication interface unit 110 communicates with a master station (not shown) or a secondary station (not shown) using a serial communication standard according to a distributed network protocol.

The serial communication standard may for example be RS-232C. The distributed network protocol may also be DNP 3.0.

As described above, the hierarchical structure of DNP 3.0 includes an application layer, a virtual transport layer, a data link layer, and a physical layer.

When using the RS-232C, the communication interface 110 is connected to the main station or sub-station using an RS-232 serial cable.

As a connector of the RS-232 serial cable, for example, a 9-pin RS-232 connector can be used. The RS-232 connector has nine signal lines as physical data transmission and reception, but the signal lines for transmitting data to an external device, i.e., a main station or a sub station, for transmitting and receiving a DNP 3.0 message substantially. '), The input signal line (Receive Data,' RXD ') received from an external device is used.

The reason for the connection using the RS-232C serial cable is that it is an interface mainly used in a general PC or a system. Therefore, when using RS-232C, the distributed network protocol call analysis apparatus 100 may be connected to a general system to perform analysis.

4 is a diagram illustrating a wiring in the case of using an RS-232C cable in a distributed network protocol call analysis apparatus according to an embodiment of the present invention.

Referring to FIG. 4, the distributed network protocol call analysis apparatus 100 is connected to a main station or a secondary station using an RS-232C cable. In this case, the master or secondary station transmits data to the distributed network protocol call analysis apparatus 100 using the signal line for pin 3, that is, the TXD pin, and the distributed network protocol call analysis apparatus 100 transmits the data to pin 2, That is, it is received by using the signal line for the RXD pin. In addition, the distributed network protocol call analysis apparatus 100 transmits data to a main station or a sub station using a signal line for pin 3, that is, a TXD pin, and the main station or sub station transmits data to the second pin, that is, a RXD pin. To receive.

For example, if the distributed network protocol call analysis apparatus 100 is configured in a PC form to use TXD and RXD, the distributed network protocol call analysis apparatus 100 may be connected to use a corresponding COM port number to which an RS-232 serial cable is connected. Physical layer can be set.

The data generator 130 generates transmission data to be transmitted to the main or sub station.

The generation of transmission data to be transmitted to the rich station will be described in more detail as follows.

The application layer is a top layer, which receives data from a user and creates an application protocol service unit. In addition, an application header is added to the application protocol service unit to generate an application protocol data unit.

The application protocol service unit includes an object header and payload data, which is data received from the user. When the data received from the user is larger than the size defined in the application layer, the application protocol service unit may be divided into several application protocol service units.

The application header consists of control fields and function fields.

The control field is a sequence of one bit START field indicating the start of the application protocol data unit and one bit FINAL bit indicating the end, one bit confirmation bit serving to wait for an acknowledgment from the destination, and a unit of application protocol data. It consists of 5 bits of order bits. The confirmation bit may be directly selected by the user when using the distributed network protocol call analysis apparatus 100 according to the present invention.

The function field is configured to allow the user to directly select the function code field defined in DNP 3.0 when using the distributed network protocol call analysis apparatus 100 according to the present invention to describe the purpose of the user data.

When using the distributed network protocol call analysis apparatus 100 according to the present invention, if a user selects a function code, sets whether or not to receive an acknowledgment after making a physical connection, and requests a transmission, the data generator 130 may apply an application protocol. Create a data unit, and the application protocol data unit is delivered to the virtual transport layer. In the distributed network protocol call analysis apparatus 100 according to the present invention, the user data may be generated as arbitrary numeric data.

The configuration of the virtual transport layer consists of the header and data of the virtual transport layer. To distinguish the application protocol data units that are divided in the virtual protocol transport layer, the header of the virtual transport layer includes a START bit indicating the start of one bit of data, a FINAL bit indicating the end of one bit of data, and virtual transport data. It consists of a size of 1 byte including 6 bits of order bits indicating the order of.

The data portion of the virtual transport layer should be divided into a maximum of 249 bytes when the size of the protocol data unit received from the application layer is at least 249 bytes. That is, if the maximum size of the virtual transport protocol data unit is 250 bytes and the header of 1 byte is excluded, the maximum size of the data portion is 249 bytes.

First, the application protocol data unit received from the application layer is stored in a temporary storage space (buffer). When the size of the temporary storage space is determined, it may be determined whether to divide based on Equation 1.

Here, [x] is an operator that outputs the maximum value among integers smaller than x. In addition, BufferSize is greater than 0 and indicates the size of the temporary storage space in bytes.

Using the result value N from Equation 1, it is possible to determine how many virtual transport protocol data units should be divided into application protocol data units.

If the value of N is 0 or less than 249 bytes, there is no need to divide the application protocol data unit into multiple virtual transport protocol data units.

If the value of N is greater than 0, the application protocol data unit is divided into (N + 1) virtual transport protocol data units.

When splitting, set the START flag bit in the header of the first virtual transport protocol unit to 1, and the FINAL flag bit to 0 to indicate that it is the first part of the split virtual transport protocol unit, and set 1 to the sequence field bit. In addition, set the header. In addition, a total of 249 bytes from the 0th to 248th bytes of the temporary storage space are stored in the data portion of the virtual transport protocol data unit.

From the first virtual transport protocol unit that is continuously divided to the Nth virtual transport protocol unit, the START flag bit of the header is set to 0 and the FINAL flag bit is also set to 0 to middle the unit of the divided virtual transport protocol unit. Set the header by adding 1 to the sequence field. Also, a total of 249 bytes are stored in the data portion of the transport protocol data unit from (i * 249) th to (((i + 1) * 249)-1) th of the temporary storage space (i is 1 to N-1. Is an integer up to).

Finally, the (N + 1) th divided virtual transport protocol unit sets the START flag bit in the header of the unit to 0 and the FINAL flag bit is set to 1 to indicate that it is the last unit of the divided virtual transport protocol. Add 1 to the field to complete the header configuration. In the temporary storage space, the data of (N * 249) through (((N + 1) * 249)-1) or less than the remaining 249 bytes in size is stored in the data portion of the virtual transport protocol data unit. To complete.

The partitioned virtual transport data unit is sent to the lower data link layer.

The data link layer provides the ability to create a reliable physical layer, and provides error detection and duplicate frame detection. The protocol data unit of the data link layer is referred to as a frame, and receives a virtual transport data unit from an upper virtual transport layer to form a data link layer header and transmit the data link layer header to the physical layer.

The frame consists of a data link header and user data.

The data link header contains two bytes of start field, one byte of length field, one byte of management field, two bytes of destination address field, two bytes of source address field, two bytes of periodic redundancy check ('CRC'). ) Field.

The start field of the data link header is 2 bytes consisting of hexadecimal 0x05 and 0x64, which is used as a protocol identifier of DNP 3.0 and is also used as a start field.

The length field indicates the total length of the frame except for 2 bytes of the start field and 1 byte of the length field itself.

The management field checks the validity of the 1-bit DIR field indicating the physical transmission direction, the 1-bit PRM field indicating the station generating the message, the 1-bit FCB field used for synchronization between the main and sub-stations, and the FCB field. It consists of a 1-bit FC V field, a 1-bit DFC field indicating whether or not the sub-station data can be received, and a 4-bit function code indicating the purpose of the data of the DNP 3.0 data link layer.

The address field is configured in a little endian manner, and in a data link, user data has a total of 16 data blocks in which one block is 16 bytes maximum.

The data block is composed of user data and CRC.

The total length of the data link in DNP 3.0 adds up to 292 bytes in total, including the 2-byte start field in the header, which is not calculated in the length field, the 2-byte periodic append check, and the 1-byte length field.

The data link layer adds the data link header to the virtual transport protocol data unit received from the upper virtual transport layer and delivers it to the physical layer.

The physical layer then transmits the DNP 3.0 request message to the sub-station connected to the distributed network protocol call analysis apparatus 100 via a serial cable through the communication interface 110.

The generation of transmission data to be sent to the master station is described in detail later.

The data analysis unit 150 analyzes the received data received from the main station or the sub station.

The analysis of the received data received from the master station will be described in more detail as follows.

When the distributed network protocol call analysis apparatus 100 receives the DNP 3.0 request message from the host station, the distributed network protocol call analysis apparatus 100 receives the DNP 3.0 request message from the physical layer, and then passes the data link layer to be analyzed.

The data link layer separates the received DNP 3.0 request message into a data link header and a data portion.

First, it analyzes the data link header and checks if the first two bytes are hexadecimal 0x0564 to confirm that the received message is a DNP 3.0 message. After that, it compares the destination address of the header with its own address and checks whether the address is the same to see if it is DNP 3.0 data. In addition, the value of the header length field is checked to confirm the length of data link data to be delivered from the received DNP 3.0 message to the virtual transport header, which is the upper layer of the data link layer. In other words, if the length field value is added with 2 bytes of the start field, 1 byte of the length field, 2 bytes of CRC bits, and 5 bytes in total, the length of the entire data of the data link layer is obtained. It can be confirmed that the length of is correctly received.

If there is no problem with the header, the data portion is passed to the virtual transport layer.

By analyzing the header portion of one byte in the virtual transport layer, one bit of the FIRST bit and one bit of the FINAL bit can be used to distinguish whether or not the current data is divided data.

If the FIRST bit is 1 and the FINAL bit is 1, it is passed directly to the application layer as single undivided data.

If the FIRST bit is 1 and the FINAL bit is 0, it indicates that it is the first of the divided data and stores it in a temporary variable. Until the data with the transport header with the FIRST bit 0 and the FINAL bit is 1 is received. Order the value of the order field of the header with the FIRST bit 1 and the FINAL bit 0 first, then the value of the order field of the data with the FIRST bit 0 and the FINAL bit 1 last. Reassemble the partitioned data.

The reassembled data is delivered to the application layer as an application data protocol unit.

The application protocol data unit received at the application layer is divided into an application header and an application service data unit, and the application service data unit is separated into an object header and data.

The application header consists of a control field of 1 byte and a function field of 1 byte.

The control field consists of a 1-bit FIRST bit field, a 1-bit FINAL bit field, a 1-bit acknowledgment bit field, and a 5-bit order bit field.

If the FIRST bit is 1 and the FINAL bit is 1, then it is a single unpartitioned application service data unit. If the FIRST bit is 1 and the FINAL bit is 0, this indicates that it is the first application service data unit of the divided application service data units. Store the application service data unit part in the order of the order field values in the control field of the application header until the application protocol data unit with the control field of the application header with the FIRST bit 0 and the FINAL bit 1 is received. Restart the partitioned Application Service Data Unit with the first position of the value of the Order field of the bit 1 and FINAL bit 0, then the value of the Order field of the data with the FIRST bit 0 and the FINAL bit 1 last. Assemble

In addition, it is necessary to generate an acknowledgment message when the value of the acknowledgment bit field of the control field is 1 to confirm an acknowledgment. When 0, it does not generate an acknowledgment message. That is, a confirmation message is optionally generated.

Meanwhile, when generating a confirmation message, the data analyzer 150 transmits the corresponding item to generate the confirmation message to the data generator 130.

Analyzing the value of the function field, on the other hand, can be used to understand what the host country is asking for.

When the data analysis unit 150 analyzes the DNP 3.0 request message received from the master station, when the confirmation response is requested, the data generator 130 generates a confirmation message and transmits the confirmation message to the master station. In this case, the data generator 130 sets the bit value of the function field of the application header of the confirmation message to a binary '00000000' to inform it of the confirmation message.

In addition, the data generation unit 130 generates a DNP 3.0 response message and transmits it to the master station. In this case, the data generation unit 130 sets the bit value of the function field of the application header of the response message to a binary '10000001' to inform that the response message.

The data generator 130 generates transmission data to be transmitted to the master station, that is, a confirmation message or a response message through the following process.

First, set the bit value of the function field and transfer it to the virtual transport layer. Since the size of the received application protocol data unit is not divided in the virtual transport layer since it is not divided into 249 bytes, the virtual transport header is added, and then the virtual transport protocol data unit is transferred to the lower data link layer. Thereafter, the data link layer changes the control field of the data link header from the sub-station to the main station, sets the destination address field to the address of the main station, and sets the source address field to the address of the distributed network protocol call analysis apparatus 100. do. Then, the received virtual transport protocol data unit is added to the physical layer after the data link header.

The physical layer then transmits the DNP 3.0 response message to the master station connected to the distributed network protocol call analysis apparatus 100 via a serial cable through the communication interface 110.

Meanwhile, the data analyzer 130 analyzes the received data, that is, the confirmation message or the response message, received from the rich station through the following process.

The data analyzer 130 analyzes whether an acknowledgment or a response is sent through the analysis process of the physical layer, the data link layer, the virtual transport layer, and the application layer as in the case of receiving a DNP 3.0 request message from the secondary station. do.

Since this process is similar to the above-described data analysis, a detailed description thereof will be omitted.

The operation state determination unit 170 determines the operation state of the main station or sub-station based on the received data analysis result of the data analysis unit 150.

For example, when the received data received by the main station or sub station is not normal or when the received data is not received, the operation state determination unit 170 may determine that the main station or sub station is not in the normal state.

When the distributed network protocol call analysis apparatus 100 operates as a primary station and tests the operation of the secondary station, the distributed network protocol call analysis apparatus 100 transmits a DNP 3.0 request message to the secondary station, and the secondary station confirms the request message. Thereafter, the sub-station sends an acknowledgment message to the distributed network protocol call analysis apparatus 100 when the value of the one bit confirmation bit is set to 1 in the management field of the application header of the application layer in the request message, and the value of the confirmation bit is 0. If it is set to, the secondary station composes a response message to be sent to the distributed network protocol call analysis apparatus 100 and transmits it to the distributed network protocol call analysis apparatus 100. When the distributed network protocol call analysis apparatus 100 receiving the response message has a value of 1 bit of the confirmation bit set in the management field of the application layer of the response message, the distributed network protocol call analysis apparatus 100 sends a confirmation message. If the value of the confirmation bit is set to 0, the operation state determination unit 170 may confirm that data has been correctly transmitted and received.

When the distributed network protocol call analysis apparatus 100 operates as a sub-station and tests the operation of the master, the distributed network protocol call analysis apparatus 100 generates a voluntary response message and transmits it to the master. In this case, it is configured to receive the confirmation message by setting the value of the 1-bit confirmation bit to 1 in the management field of the application layer of the response message. Thereafter, if a confirmation message is received from the master station, the operation state determining unit 170 may confirm that the master station operates normally.

The above is summarized as follows.

The data generator 130 generates at least one of a response message and an optional acknowledgment message for transmitting to the master station, or generates at least one of a request message and an optional acknowledgment message for transmitting to the secondary station.

In addition, the data analyzer 150 analyzes at least one of a request message and an optional acknowledgment message received from the master station, or analyzes at least one of a response message and an optional acknowledgment message received from the secondary station.

The operation state determination unit 170 determines whether the master station or the sub station is in normal operation by determining whether there is an abnormality in at least one of a request message and an optional confirmation message received from the master station or at least one of a response message and an optional confirmation message received from the sub station. do.

Meanwhile, the response message for transmitting to the master station generated by the data generator 130 may include a response message generated for the request message received from the master station and a voluntary response message generated regardless of the request message received from the master station. have.

If a response message and a voluntary response message are generated at the same time, a problem may arise that which message should be sent to the master station first.

In this case, the communication interface 110 may first transmit a response message to the master station. The response message may be transmitted first for all remaining requests except when the function field of the application header has a value of '00000001' that is READ.

However, it is also possible to send a spontaneous response message first. If the value of the function field of the application header is '00000001' value of READ, the spontaneous response message may be transmitted first.

5 is a diagram illustrating message transmission and reception when a distributed network protocol call analysis apparatus is connected to a master station and operates according to an embodiment of the present invention.

In the example of FIG. 5, the distributed network protocol call analysis apparatus 100 operates as a sub-station, and determines an operation state of the master station.

Referring to FIG. 5, the master station transmits a DNP 3.0 request message to the distributed network protocol call analysis apparatus 100. The distributed network protocol call analysis apparatus 100 may transmit a selective acknowledgment message or a DNP 3.0 response message to the host station. Meanwhile, the master station may transmit a selective acknowledgment message to the distributed network protocol call analysis apparatus 100.

6 is a diagram illustrating message transmission and reception when the apparatus for analyzing a distributed network protocol call according to an embodiment of the present invention is connected to a sub-station.

In the example of FIG. 6, the distributed network protocol call analysis apparatus 100 operates as a main station and determines an operation state of the sub station.

Referring to FIG. 6, the distributed network protocol call analysis apparatus 100 transmits a DNP 3.0 request message to a rich station. The secondary station may transmit a selective acknowledgment message or a DNP 3.0 response message to the distributed network protocol call analysis apparatus 100. Meanwhile, the distributed network protocol call analysis apparatus 100 may transmit a selective confirmation message to the sub-station.

In addition, the distributed network protocol call analysis apparatus 100 according to an embodiment of the present invention may further include an operation state output unit 190.

The operation state output unit 190 outputs whether the main station or the sub station is in normal operation according to the determination result of the operation state determination unit 170.

Therefore, the user of the distributed network protocol call analysis apparatus 100 may check whether the master station or the sub station is abnormal. For example, if you are developing a master or secondary station device, you can check for design anomalies.

7 is a block diagram of a distributed network protocol call analysis apparatus according to another embodiment of the present invention.

Referring to FIG. 3, the distributed network protocol call analysis apparatus 100 ′ according to another embodiment of the present invention may include a communication interface 110 ′, a data analyzer 150 ′, and an operation state monitoring unit 170. Contains'). In addition, the distributed network protocol call analysis apparatus 100 ′ according to another embodiment of the present invention may further include a transmission / reception data output unit 190 ′.

The communication interface 110 ′ receives and transmits and receives data transmitted and received between a main station and a sub station using a serial communication standard according to a distributed network protocol.

The serial communication standard may for example be RS-232C. The distributed network protocol may also be DNP 3.0.

FIG. 8 is a diagram illustrating a wiring when an RS-232C cable is used in a distributed network protocol call analysis device according to another embodiment of the present invention.

Referring to FIG. 8, the communication interface 110 ′ is configured with two ports to receive the same data as the data exchanged between the main station and the sub-station in real time.

In order to receive the data transmitted from the master station to the sub-station, a new connection should be made in the line connecting the TXD of the master station and the RXD of the sub-station and connected to the RXD of the communication interface 110 '. In addition, in order to receive data transmitted from the sub-station to the main station, a new connection must be made in the line connecting the TXD of the sub-station and the RXD of the main station to connect to the RXD of the communication interface 110 '. However, since the S-232 9 pin has only one RXD, the communication interface 110 'can receive contents transmitted from the main station and the sub-station at the same time by using two cable connectors.

That is, the communication interface unit 110 ′ may include a first RS-232C communication interface unit for receiving transmission / reception data transmitted from the master station to the secondary station, and a second RS-232C communication interface for reception of transmission / reception data transmitted from the secondary station to the master station. It may include wealth.

The data analyzer 150 ′ analyzes the transmission and reception data received by the communication interface 110 ′ according to a distributed network protocol.

The transmission / reception data may include at least one of a request message and an optional acknowledgment message received from the master station. In addition, the transmission and reception data may include at least one of a response message and an optional acknowledgment message transmitted and received from the sub-station.

Since the analysis of data according to the distributed network protocol is as described above, a detailed description thereof will be omitted.

The operation state monitoring unit 170 ′ monitors the operation state of the main station or the sub-station based on the transmission / reception data analysis result of the data analysis unit 150 ′. That is, the operation state monitoring unit 170 ′ determines whether there is an abnormality in at least one of a request message and an optional acknowledgment message received from the master station or at least one of a response message and an optional acknowledgment message received from the sub station to determine the operation state of the master station or the sub station. Can be monitored.

When abnormality of the transmission / reception data occurs, the operation state monitoring unit 170 ′ may determine that the operation of the main station or the sub station is not normal. In addition, the operation state monitoring unit 170 ′ may check the contents of the transmission / reception data between the master station and the sub-station.

Meanwhile, the distributed network protocol call analysis apparatus 100 ′ according to another embodiment of the present invention may further include a transmission / reception data output unit 190 ′.

The transmission / reception data output unit 190 ′ outputs transmission / reception data received through the communication interface unit 100 ′.

Therefore, the user of the distributed network protocol call analysis apparatus 100 ′ can easily check the data transmitted and received between the master station and the secondary station.

FIG. 9 is a diagram illustrating message transmission and reception when a distributed network protocol call analysis apparatus is connected to a master station and a secondary station according to another embodiment of the present invention.

As shown, the distributed network protocol call analysis apparatus according to another embodiment of the present invention is connected to both the main station and the sub-station, and a request message or an optional acknowledgment message transmitted by the master station to the sub-station, and an optional acknowledgment message transmitted by the sub-station to the master station. Alternatively, you can receive both response messages.

According to another embodiment of the present invention as described above, it is possible to monitor the data transmitted and received between the main station and the sub-station.

Although the configuration of the present invention has been described in detail, these are merely illustrative of the present invention, and various modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. This will be possible.

Therefore, the embodiments disclosed herein are not intended to limit the present invention but to describe the present invention, and the spirit and scope of the present invention are not limited by these embodiments. It is intended that the scope of the invention be interpreted by the following claims, and that all descriptions within the scope equivalent thereto will be construed as being included in the scope of the present invention.

As described above, according to the present invention, it is possible to test the operation of the DNP 3.0 master and sub-stations, and to minimize the functional constraints of the physical layer when analyzing and monitoring the DNP 3.0 protocol data units transmitted and received between the main and sub-stations. It is easy to apply to general system by analyzing and monitoring by connecting to COM port of PC using RS-232 cable. In particular, by simulating the functions of the host and the sub-stations of DNP 3.0, the host generates the DNP 3.0 request message and delivers the request message to the sub-station, and the sub-station composes a response message suitable for the received request message and delivers the response message to the master. Can be tested. It may also test the ability of the rich country to generate a voluntary response message and send it to the host country.

In addition, according to the present invention can analyze the DNP3.0 protocol data unit transmitted and received between the DNP 3.0 master and sub-stations during the development or completed development, it is possible to monitor the functions of the master and sub-stations, the DNP developed using the simulation function You can analyze and monitor DNP 3.0 messages from 3.0 host or sub stations.

1 is a diagram illustrating message transmission and reception between a main station and a sub station using DNP 3.0.

2 is a diagram illustrating a usage environment of a distributed network protocol call analysis apparatus according to the present invention.

3 is a block diagram of a distributed network protocol call analysis apparatus according to an embodiment of the present invention.

Figure 4 is a diagram showing the wiring when using an RS-232C cable in a distributed network protocol call analysis apparatus according to an embodiment of the present invention.

5 is a diagram illustrating message transmission and reception when a distributed network protocol call analysis apparatus is connected to a master station and operates according to an embodiment of the present invention.

6 is a diagram illustrating message transmission and reception when a distributed network protocol call analysis apparatus is connected to a sub-station according to an embodiment of the present invention.

7 is a block diagram of a distributed network protocol call analysis apparatus according to another embodiment of the present invention.

8 is a diagram illustrating a connection when using an RS-232C cable in a distributed network protocol call analysis apparatus according to another embodiment of the present invention.

FIG. 9 is a diagram illustrating message transmission and reception when a distributed network protocol call analysis apparatus is connected to a main station and a secondary station according to another embodiment of the present invention. FIG.

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

100, 100 ': distributed network protocol call analysis device

110 and 110 ′: communication interface 130: data generator

150, 150 ': data analysis unit 170: operation state determination unit

170 ': operation state monitoring unit 190: operation state output unit

190 ': transmit / receive data output

Claims (13)

A distributed network protocol call analysis device for analyzing the operation of a master station or a sub station according to a distributed network protocol,  A communication interface unit for communicating with the main station or the sub-station using a serial communication standard according to the distributed network protocol; A data generator for generating transmission data to be transmitted to the master station or the sub-station; A data analyzer for analyzing received data received from the master station or the sub-station; An operation state determination unit that determines an operation state of the master station or the sub- station based on the received data analysis result of the data analyzer Distributed network protocol call analysis device comprising a. The method of claim 1, The serial communication standard is RS-232C distributed network protocol call analysis device. The apparatus of claim 1, wherein the distributed network protocol is DNP (Distributed Network Protocol) 3.0. The method of claim 1, The data generating unit generates at least one of a response message and an optional acknowledgment message for transmitting to the master station, or generates at least one of a request message and an optional acknowledgment message for transmitting to the secondary station, The data analyzer analyzes at least one of a request message and an optional acknowledgment message received from the master station, or analyzes at least one of a response message and an optional acknowledgment message received from the sub-station. The operation state determination unit determines whether or not the master station or the sub station operates normally by determining whether at least one of a request message and an optional confirmation message received from the master station or at least one of a response message and an optional confirmation message received from the sub station is abnormal. Distributed network protocol call analysis device to determine. The method of claim 4, wherein The response message for transmitting to the master station generated by the data generator includes a first response message generated for the request message received from the master station and a second response message generated regardless of the request message received from the master station. To do it, The communication interface unit, if the first response message and the second response message is generated at the same time distributed network protocol call analysis apparatus preferentially transmits the second response message to the master station. The method of claim 4, wherein The response message for transmitting to the master station generated by the data generator includes a first response message generated for the request message received from the master station and a second response message generated regardless of the request message received from the master station. To do it, The communication interface unit, if the first response message and the second response message is generated at the same time distributed network protocol call analysis apparatus preferentially transmits the first response message to the master station. The method of claim 1, An operation state output unit for outputting whether the main station or the sub- station is in normal operation according to a determination result of the operation state determination unit Distributed network protocol call analysis device further comprising. A distributed network protocol call analysis device for analyzing communication between a master station and a sub station according to a distributed network protocol, A communication interface for receiving transmission and reception data transmitted and received between the master station and the sub-station using a serial communication standard according to the distributed network protocol; A data analyzer for analyzing the transmission / reception data according to the distributed network protocol; An operation state monitoring unit configured to monitor an operation state of the master station or the sub-station based on a result of the transmission / reception data analysis of the data analysis unit; Distributed network protocol call analysis device comprising a. The apparatus of claim 8, wherein the serial communication standard is RS-232C. The method of claim 9, The communication interface unit, A first RS-232C communication interface unit for receiving the transmission / reception data transmitted from the master station to the sub-station; A second RS-232C communication interface unit for receiving the transmission / reception data transmitted from the sub station to the master station Distributed network protocol call analysis device comprising a. The apparatus of claim 8, wherein the distributed network protocol is DNP (Distributed Network Protocol) 3.0. The method of claim 8, The data analysis unit analyzes the transmission / reception data including at least one of a request message and an optional confirmation message received from the master station, or analyzes the transmission / reception data including at least one of a response message and an optional confirmation message received from the secondary station. To do it, The operation state monitoring unit monitors the operation state of the master station or the sub-station by determining whether there is an abnormality of at least one of a request message and an optional acknowledgment message received from the master station or at least one of a response message and an optional acknowledgment message received from the sub-station. Distributed network protocol call analysis device. The method of claim 8, Transmission and reception data output unit for outputting the transmission and reception data Distributed network protocol call analysis device further comprising.

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