KR20150054414A - Redundancy Check Method for Communication Data using Receiving Buffer in Redundancy Apparatus - Google Patents

Abstract

The present specification discloses a redundancy check method. In an apparatus having a redundancy function such as PRP or HSR protocol, the method can quickly check for redundancy in real-time within communication data between devices by using a receiving buffer.

Description

Technical Field [0001] The present invention relates to a redundancy checking method for communication data using a receiving buffer in a redundancy apparatus,

More particularly, the present invention relates to a method for redundant checking of communication data in a duplexer, and more particularly, to a duplexer employing a redundant redundancy function such as PRP or HSR protocol, The present invention relates to a redundant inspection method for real-time high-speed redundant detection.

The Parallel Redundancy Protocol (PRP) and High-availability Seamless Redundancy (HSR) protocols of IEC 62439-3 are used in substation automation devices such as Intelligent Electronic Devices (IED) to prevent data transmission errors and to ensure full data transmission. It is a protocol for providing redundancy.

In an IED device to which redundancy redundancy function of PRP or HSR protocol is applied, a duplicated frame (or packet) is transmitted and received through two paths on the Ethernet-based Internet, so that even if one data frame is not transmitted due to a failure, Thereby guaranteeing data transmission. PRP redundancy is a scheme in which a single device such as an IED device communicates with two local networks to transmit and receive parallel frames in a parallel manner. HSR redundancy is a method in which, among the devices connected to each other, And transmits and receives overlapping frames one by one in the clockwise direction and the counterclockwise direction through the connection line of the form.

However, in the case of an IED device to which a redundancy redundancy function is applied, the same data frame due to duplication is received redundantly. To solve this problem, a frame received in a link redundancy entity (LRE) It is judged whether or not the frame is a duplicated frame.

The redundant frame discard function in the LRE checks whether the source and destination of the PRP or HSR data frame are the same as the corresponding address of the already received frame, (Or number) 'and' lane (or path) 'existing in the' HSR Tag 'field and recognizing it as a duplicate if the value is the same as the corresponding field value of the already received frame ( 1).

However, such a two-step comparison method of a specific field is pointed out as a problem that can cause a control failure due to difficulty in high-speed processing in an IED device or the like that requires real-time control.

Korean Patent Publication No. 10-1999-0058410 (published on July 15, 1999) and the like can be referred to as related prior arts.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a redundant apparatus to which redundant redundancy function such as PRP or HSR protocol is applied, And to provide a redundant inspection method capable of real-time high-speed duplication detection.

According to another aspect of the present invention, there is provided a method for duplicating communication data in a duplexer, the method comprising the steps of: (A) Storing a currently received data frame in a unit buffer (K) using a buffer bank; (B) comparing information of each buffer, which is already received and stored in one or more other unit buffers and managed, with information of the unit buffer (K) And determining whether there is a duplicate frame between any one of the one or more other unit buffers and the unit buffer (K); And (C) transmitting the information of the unit buffer (K) to an upper layer for subsequent processing according to whether the information of the unit buffer (K) is a new frame or a redundant frame or And controlling deletion of information of the unit buffer (K).

The redundancy apparatus includes a link redundancy entity (LRE) of the data link layer for performing the redundancy check in the lower layer, and the redundancy apparatus includes a link redundancy scheme in accordance with a PRP (Parallel Redundancy Protocol) or HSR (High-availability Seamless Redundancy) The redundancy check can be performed upon receiving the data frame from the device for the external redundancy redundancy function.

Wherein the data frame is a PRP (Parallel Redundancy Protocol) frame or a High-availability Seamless Redundancy (HSR) frame and the buffer bank is a unit buffer of a PRP frame or a HSR frame, Lt; / RTI >

In step (B), when the data frame is a PRP frame, information of 'destination', 'source', 'lane', and 'sequence counter' fields are sequentially compared by 1 bit in a predetermined order, In the case of the HSR frame, the information of the 'destination', 'source', 'path', and 'sequence number' fields can be sequentially compared by 1 bit in a predetermined order.

In the step (B), a comparison is made with a corresponding unit buffer in which a value different from any one bit of the comparison bits of the unit buffer K is found at the time of the sequential comparison of the bits, It can be determined that the information of the unit buffer K is a redundant frame in the presence of a unit buffer having a bit value that matches up to the last bit of the comparison bits of the buffer K. [

The information of the unit buffer K may be transmitted to the upper layer without deleting the information of the unit buffer K if the information of the unit buffer K is a new frame in step (C).

In the step (C), if the information of the unit buffer K is the redundant frame, information of the unit buffer having the redundant frame and the information of the unit buffer K may be deleted.

(C), if the information of the unit buffer (K) is the redundant frame, it is determined from the 'sequence counter' or the 'sequence number' of the currently received data frame, and if the value is a restarted value The unit buffer having the redundant frame and the information of the unit buffer K can be deleted.

According to another aspect of the present invention, there is provided a duplexer for performing duplex checking of communication data, the duplexer including a plurality of unit buffers, the buffer bank having a predetermined size or larger for storing received data frames; And comparing the information of each buffer, which is already received and stored in one or more unit buffers of the buffer bank and managed, with information stored in the unit buffer K of the buffer bank currently received, A bitwise comparator for sequentially comparing each bit with respect to information of a field; A redundancy judgment unit for judging whether any one of the one or more other unit buffers is overlapped with the unit buffer (K) according to a result of the comparison; And transmitting information of the unit buffer (K) to an upper layer for subsequent processing according to whether the information of the unit buffer (K) is a new frame or a redundant frame based on a result of the determination, K of the information to be deleted.

According to the duplication checking method of communication data in the duplication apparatus according to the present invention, the application time point of the duplication detection technique is fixed to the reception time point of the new communication data frame, and duplication detection based on the PRP or HSR protocol among the frames stored in the reception buffer It is possible to perform high-speed duplication detection by processing in real time for each bit of the necessary information only with the corresponding field information of the already received and stored frame.

In addition, since the size of the 'sequence counter' of the PRP frame or the 'sequence number' of the HSR frame is reset and counted again, the number of frames to be subjected to the actual redundancy check is limited, Therefore, a buffer capable of high-speed processing and a simple redundancy checking method using real-time comparison processing for each bit can be usefully used for real-time high-speed redundancy testing.

1 is a diagram for explaining a structure of a data frame according to a general PRP and HSR protocol.
FIG. 2 is a view for explaining the concept of a duplication apparatus according to an embodiment of the present invention.
3 is a diagram for explaining a configuration of a duplication checking apparatus of the duplication apparatus of FIG.
4 is a flowchart for explaining an operation method of the duplicate inspection apparatus of FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout.

First, in a conventional IED (Intelligent Electronic Devices) device to which a redundancy redundancy function of PRP (Parallel Redundancy Protocol) or HSR (High-availability Seamless Redundancy) protocol of IEC 62439-3 is applied, as described above, It checks whether the specific fields 'source' and 'destination' of the PRP or the HSR data frame are the same as the corresponding address of the already received frame, and also checks whether the 'sequence' existing in the 'PRP Tail' (or number) 'and' lane (or path) ', and recognizes it as duplicate if it is the same value as the corresponding field value of the already received frame.

The PRP or HSR data frame contains fields such as 'preamble', 'destination', 'source', 'LLC (Logical Link Control)', 'payload' and 'FCS (Frame Check Sequence)' according to the original standard Ethernet protocol , 'Sequence counter', 'lane', 'size', and 'PRP suffix' fields are added to the 'PRP Tail' of the PRP data frame and 'HSR-ET' , 'size', and 'sequence number' fields have been added.

In the present invention, in order to enable more redundant inspection at real time and high speed in a duplication device such as an IED device to which redundancy redundancy function of PRP or HSR protocol is applied, a time point of application of a redundancy detection technique is fixed as a reception time point of a new communication data frame , So that only the corresponding information required for duplication detection based on the PRP or the HSR protocol among the frames stored in the reception buffer is processed at high speed for each bit of the received frame information.

In addition, the present invention is not limited to such a configuration. However, the present invention is not limited to this, and may be applied to another type of redundant apparatus having a redundant redundancy function or a data frame Those skilled in the art will appreciate that the present invention can be easily implemented by applying the concept of the present invention to necessary modifications of hardware or software.

The duplexing apparatus to which the redundancy redundancy function of the PRP or the HSR protocol is applied may have a physical layer transceiver for transmitting and receiving redundant frames (or packets) through the two paths on the network as shown in FIG. 2, In the Link Redundancy Entity (LRE) (or link redundancy check) 100 of the data link layer, it is determined whether a data frame received through network communication is a duplicate of a frame already received, It is possible to ensure secure data transmission by deleting the data without uploading it to an upper layer. As described above, the transceiver in the case of a redundant apparatus adopting the redundancy redundancy function of the PRP protocol can communicate with two local networks and transmit and receive parallel frames in a redundant manner, and the redundancy redundancy function of the HSR protocol is applied The corresponding transceiver in the case of a duplication device can transmit and receive duplicate frames one by one in the clockwise direction and the counterclockwise direction through the ring-shaped connection line to the devices connected to each other so as to communicate with each other in a ring form on the network.

Hereinafter, the configuration and flow chart of the duplication checking apparatus of the duplication apparatus according to an embodiment of the present invention shown in FIGS. 3 and 4 will be described in more detail.

3, the redundancy checker provided in the LRE 100 of the duplication apparatus of FIG. 2 includes a bitwise comparator 110, a redundancy judgment unit 120, a control unit 130, and a buffer bank 140). To explain the operation of such a duplicate inspection apparatus, reference is now made to the flowchart of FIG.

First, the buffer bank 140 includes a plurality of identifiable unit buffers (1, 2, 3, ..., K, ..) and corresponds to a size larger than a predetermined size for storing data frames on the received network communication Lt; / RTI > In FIG. 3, the unit buffers 141, 142 and 143 indicate buffers in which data frames are already received and stored, and the unit buffers K indicate buffers in which currently received data frames are stored.

For example, if the received data frame is a PRP (Parallel Redundancy Protocol) frame or HSR (High-availability Seamless Redundancy) frame, and the received data frame is a PRP frame, and a storage space having a size larger than the maximum value indicated by the 'sequence counter'. If the received data frame is the HSR frame, the buffer bank 140 stores the maximum value indicated by the field 'sequence number' of the HSR frame Lt; RTI ID = 0.0 > buffer. ≪ / RTI >

The external device transmitting to the LRE 100 of the duplexer each time the PRP frame or the HSR frame is sequentially transmitted, the pre-defined path (or tracking) information between the external device and the corresponding duplexer, The 'sequence counter' or 'sequence number' is incremented by '1' for the information. Here, 'sequence counter' or 'sequence number' is incremented from the predetermined range (for example, minimum value 1 to maximum value 10) to the maximum value and restarted from the minimum value is repeated.

When the LRE 100 of the duplexer receives the above-mentioned data frame from the apparatus for external redundancy redundancy function in the network communication, the buffer bank 140 stores the valid unit buffers 141, 142 and 143 For example, the unit buffer K (refer to S100 in FIG. 4). The unit buffer K may be a unit buffer in which data is deleted and managed by a redundant frame as described below.

The bitwise comparator 110 first checks each valid unit buffer 141, 142, 143 (which is already received and stored in one or more unit buffers of the buffer bank 140) (K) 145 of the buffer bank 140 and the information of the currently received unit buffers 140 is compared with the information stored in the unit buffer K 145 of the buffer bank 140. The redundant check of all the unit buffers 141, 142, 143, That is, the information of the fields specified in advance, by comparing the bits of each bit (see S200 in FIG. 4).

Here, the bitwise comparator 110 outputs information necessary for redundancy checking, that is, information of 'destination', 'source', 'lane', and 'sequence counter' fields in the PRP frame in a predetermined order Can be compared. The bitwise comparator 110 may sequentially compare the information of the 'destination', 'source', 'path', and 'sequence number' fields by 1 bit in a predetermined order in the case of an HSR frame.

For example, the bit-wise comparator 110 may compare the bits of the pre-specified bits of all the unit buffers 141, 142, 143, and 145, (K) 145 and the corresponding unit buffer in which a different value is found can be stopped, and the last bit of the comparison bits of the unit buffer (K) 145 And so on.

The redundancy judgment unit 120 can judge whether there is a redundancy frame between any one of the unit buffers 141, 142 and 143 and the unit buffer K 145 according to the result of the comparison (refer to S300 in FIG. 4) ). For example, when the bit-wise comparator 110 performs a comparison up to the last bit of the comparison bits of the unit buffer (K) 145 and outputs a signal indicating the presence or absence of a unit buffer having the same bit value Quot; logic high " in case of " logic low " Accordingly, in the case of 'logic high' indicating the existence of a unit buffer having a bit value matched to the last bit of the comparison bits of the unit buffer (K) 145, (K) 145 is judged to be a redundant frame. Otherwise, it is determined that the frame is a new frame that is not a duplicate, and information (frame) of the unit buffer (K) Related information such as a corresponding identification number of a unit buffer having a redundant frame or information indicating that the frame is a new frame to the controller 130.

The control unit 130 receives the result of the determination by the redundancy determining unit 120 and determines whether the information of the unit buffer K is a new frame or a redundant frame based on the received information, It is possible to control transmission to the upper layer for processing or deletion of information of the unit buffer K. [

For example, when the information of the unit buffer K is a new frame, the controller 130 transmits the information of the unit buffer K to the upper layer without deleting the information of the unit buffer K, Layer, a transport layer, a session layer, a presentation layer, an application layer, and the like (see S400 in FIG. 4). At this time, the information of the unit buffer K is stored and held as a comparison object buffer upon reception of another frame.

In addition, when the information of the unit buffer K is a redundant frame, the control unit 130 may delete the information (frame) of the unit buffer K and the corresponding unit buffer having the redundant frame. In this case, if it is judged from the 'sequence counter' or the 'sequence number' of the currently received data frame of the unit buffer K and the value is a reset value (for example, minimum value 1) The information of the unit buffer and the unit buffer K can be deleted (refer to S500 in FIG. 4). The unit buffers deleted and managed as described above are used as buffers for storing other data frames received subsequently.

If the information of the unit buffer K is a redundant frame, the control unit 130 stores a corresponding identification number of a unit buffer having a frame overlapping the information (frame) of the unit buffer (K) 145 Related information to an upper layer such as a network layer, a transport layer, a session layer, a presentation layer, and an application layer, and controls the frame of the unit buffer to be preferentially processed. For example, in an upper layer, an instruction including a frame related to a corresponding identification number of a unit buffer having a redundant frame among a plurality of commands in a standby state may be preferentially processed.

As described above, in the redundancy check performed by the redundancy checker provided in the LRE 100 of the duplexer according to the embodiment of the present invention, the size of the 'sequence counter' of the PRP frame or the 'sequence number' of the HSR frame Thus, it is possible to perform high-speed real-time high-speed redundancy check using a buffer of a suitably limited size. Therefore, a simple redundancy check method using a buffer capable of high-speed processing and a real- And can be usefully used for inspection.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. This is possible. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the equivalents of the claims, as well as the claims.

A Link Redundancy Entity (LRE)
The bit-
The redundancy judgment unit 120,
The controller 130,

Claims (9)

A duplication checking method for communication data in a duplication apparatus,
(A) storing a currently received data frame in a unit buffer (K) using a buffer bank capable of storing data of a predetermined size or more;
(B) comparing information of each buffer, which is already received and stored in one or more other unit buffers and managed, with information of the unit buffer (K) And determining whether there is a duplicate frame between any one of the one or more other unit buffers and the unit buffer (K); And
(C) transmitting information on the unit buffer (K) to an upper layer for subsequent processing according to whether the information of the unit buffer (K) is a new frame or a redundant frame, Controlling deletion of information of the unit buffer (K)
Wherein the redundant check of the communication data in the redundant apparatus is performed. The method according to claim 1,
Wherein the redundancy apparatus includes a link redundancy entity (LRE) of the data link layer for the redundancy check in a lower layer of the upper layer,
Wherein the redundancy check is performed at the time of receiving the data frame from an apparatus for an external redundancy redundancy function according to PRP (Parallel Redundancy Protocol) or HSR (High-availability Seamless Redundancy) protocol in the LRE. A method for checking duplication of communication data in a communication network. The method according to claim 1,
Wherein the data frame is a PRP (Parallel Redundancy Protocol) frame or a HSR (High-availability Seamless Redundancy) frame,
Wherein the buffer bank includes unit buffers equal to or greater than a maximum value of a field 'sequence counter' of the PRP frame or a field 'sequence number' of the HSR frame. The method of claim 3,
In step (B)
The information of the 'destination', 'source', 'lane', and 'sequence counter' fields is sequentially compared by 1 bit in a predetermined order when the data frame is a PRP frame,
Wherein when the data frame is an HSR frame, information of 'destination', 'source', 'path', and 'sequence number' fields are sequentially compared by 1 bit in a predetermined order. Of duplicate inspection method. The method according to claim 1,
In the step (B), a comparison is made with a corresponding unit buffer in which a value different from any one bit of the comparison bits of the unit buffer K is found at the time of the sequential comparison of the bits, And determines that the information of the unit buffer (K) is a redundant frame in the presence of a unit buffer having a bit value that matches all of the last bits of the comparison bits of the buffer (K). Redundancy check method. The method according to claim 1,
(K) is transmitted to the upper layer without deleting the information of the unit buffer (K) when the information of the unit buffer (K) is a new frame in step (C) A method for redundant checking of communication data in a redundant device. The method according to claim 1,
(C), if the information of the unit buffer (K) is the redundant frame, deletes the information of the corresponding unit buffer having the redundant frame and the unit buffer (K) Data redundancy check method. The method of claim 3,
In the step (C), if the information of the unit buffer K is the redundant frame,
And deletes the information of the corresponding unit buffer having the redundant frame and the unit buffer K if the value is determined to be a restarted value based on the 'sequence counter' or the 'sequence number' of the currently received data frame A method for checking duplication of communication data in a duplication apparatus. A duplicating apparatus for performing redundancy checking of communication data,
A buffer bank including a plurality of unit buffers, the buffer bank having a predetermined size for storing received data frames;
And comparing the information of each buffer, which is already received and stored in one or more unit buffers of the buffer bank and managed, with information stored in the unit buffer K of the buffer bank currently received, A bitwise comparator for sequentially comparing each bit with respect to information of a field;
A redundancy judgment unit for judging whether any one of the one or more other unit buffers is overlapped with the unit buffer (K) according to a result of the comparison; And
Whether the information of the unit buffer K is a new frame or a redundant frame, based on the result of the determination, the information of the unit buffer K to the upper layer for subsequent processing, And a control unit for controlling whether or not to delete the information of the redundant information.

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