Communication device supporting IP-based RAPIEnet and network system including the same

Abstract

In one embodiment of the present invention, a communication device includes: a communication unit; and a processor that, when a network configured with a first topology including a star topology or a line topology is included on a communication path connecting the communication device and another communication device, configures data to be transmitted to the other communication device through a first interface for accessing an upper layer based on a Real-time Automation Protocols for Industrial Ethernet (RAPIEnet) and a lower layer based on an Internet Protocol (IP), and transmits the data to the other communication device using the communication path via the communication unit.

Description

[Technical Field]

[0001] The present invention relates to a communication device that supports IP-based RAPIEnet and a network system including the same. [Background technology]

[0002] RAPIEnet (Real-time Automation Protocols for Industrial Ethernet), which includes IEC 61158-3 type 21, IEC 61158-4 type 21, IEC 61158-5 type 21, IEC 61158-6 type 21, and IEC 62439-7, refers to Ethernet-based high-availability industrial network protocols that support ring or line topologies.

[0003] In order to perform functions such as optimal transmission routes, automatic network configuration, and automatic ring manager selection, RAPIEnet manages information about the entire network in a network information base (NIB, IEC 62439-7 4.5) based on hop counts.

[0004] Hop counts can only be calculated if the frames used to manage the network can be understood between communication devices, and in order to perform functions such as searching for the optimal transmission route when the network connections are unknown, all communication devices on the network must be able to support RAPIEnet.

[0005] Due to these characteristics, a separate dedicated switch that supports RAPIEnet is required to configure a star or tree network topology using RAPIEnet.General-purpose Ethernet switches cannot provide information on the negotiation process for network configuration at the RAPIEnet Data Link layer, so it is impossible to add or expand a network using a general-purpose Ethernet switch.

[0006] However, due to the diverse control requirements of industrial sites that use RAPIEnet, there is an increasing need for functionality that can support RAPIEnet in star and tree network topologies using general-purpose Ethernet switches. Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a communication device and a network system including the same that can operate RAPIEnet-based applications even in a star or tree network topology using a general-purpose Ethernet switch.

[0008] An object of the present invention is to provide a communication device and a network system including the same, which allows a general communication device that cannot implement a RAPIEnet Data Link layer for RAPIEnet communication to transmit and receive data using a RAPIEnet application. [Means for solving the problem]

[0009] In a communication device according to an embodiment of the present invention, a communication unit is provided; and a star topology or treeand a processor that, when a network configured with a first topology including a first topology is included, configures data to be transmitted to the other communication device through a first interface for accessing an upper layer based on RAPIEnet (Real-time Automation Protocols for Industrial Ethernet) and a lower layer based on IP (Internet Protocol), and transmits the data to the other communication device using the communication path through the communication unit.

[0010] The data is first data, and when a network configured with the first topology is not included on the communication path, the processor selects one of the first interface or a second interface for accessing an upper layer of the RAPIEnet base and a lower layer of the RAPIEnet base, constructs second data to be transmitted to the other communication device through the selected first interface or the second interface, and transmits the data to the other communication device using the communication path through the communication unit.

[0011] The data is first data, and the processor identifies header information included in third data received from the other communication device, and if the header information includes header information related to the first interface, the processor can receive the third data through the first interface.

[0012] The processor may configure the data to include header information related to the first interface.

[0013] The header information may include a Destination Address, a Source Address, a Destination Service Access Point (SAP), a Source SAP, an Extension Data area, and a Group Data area.

[0014] A network system according to one embodiment of the present invention includes a plurality of communication devices including a first communication device and a second communication device, wherein the first communication device includes a first communication unit; and when a network configured with a first topology including a star topology or a line topology is included on a communication path connecting the first communication device and the second communication device, the first communication device includes a processor that configures data to be transmitted to the second communication device through a first interface for accessing an upper layer based on RAPIEnet (Real-time Automation Protocols for Industrial Ethernet) and a lower layer based on IP (Internet Protocol), and transmits the data to the second communication device using the communication path via the first communication unit; and the second communication device includes a second communication unit; and a second processor that identifies header information included in the data received from the first communication device, and receives the data through the first interface if the header information includes header information related to the first interface.

[0015] The first processor may configure the data to include header information related to the first interface.

[0016] The network system according to an embodiment of the present invention may further include at least one Ethernet switch on a communication path connecting the first communication device and the second communication device.

[0017] In one embodiment of the present invention, a communication device using a first communication method that uses a data link hierarchy based on multiple Ethernet ports can communicate with another communication device using a second communication method that uses a data link hierarchy based on a single Ethernet port.

[0018] The first communication method and the second communication method may be connection-non-oriented communication methods.

[0019] The first communication method may be RAPIEnet communication, and the second communication method may be UDP / IP communication.

[0020] When communicating with the other communication device in the second communication method, the communication device can communicate using header information required for the second communication method.

[0021] When the communication device exists in a network with a ring topology or a line topology and the other communication device exists in a network with a star topology or a tree topology, the communication device can communicate with the other communication device in the second communication method.

[0022] When communication with the other communication device fails in the first communication method, the communication device can attempt communication in the second communication method.

[0023] The communication device can communicate with the other communication device in the first communication method or the second communication method selected by a user input. [Effects of the Invention]

[0024] According to one embodiment of the present invention, a network-based control system can be configured to suit various field situations by enabling RAPIEnet-based applications to be used in networks configured with star or tree topologies.

[0025] According to one embodiment of the present invention, even general communication devices that cannot implement the RAPIEnet Data Link layer for RAPIEnet communication can transmit and receive data using RAPIEnet applications, thereby providing flexibility in network configuration.

[0026] According to an embodiment of the present invention, RAPIEnet applications can be used without modification even in a network having a topology that does not allow existing RAPIEnet communication, which is efficient and economical. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a diagram illustrating a network system configured with a plurality of communication devices supporting RAPIEnet. [Figure 2] 1 is a diagram illustrating a RAPIEnet protocol stack according to an embodiment of the present invention. [Figure 3] 1 is a diagram illustrating a RAPIEnet protocol stack according to an embodiment of the present invention. [Figure 4] 10 is a diagram illustrating header information related to a UDP interface according to an embodiment of the present invention. [Figure 5] 1 is a block diagram illustrating the configuration of a communication device according to an embodiment of the present invention. [Figure 6] 1 is a diagram illustrating a network system configured with a plurality of communication devices supporting RAPIEnet according to an embodiment of the present invention. [Figure 7] 10 is a diagram illustrating a network system configured with a plurality of communication devices supporting RAPIEnet according to another embodiment of the present invention. [Figure 8] 10 is a diagram illustrating a network system configured with a plurality of communication devices supporting RAPIEnet according to yet another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0028] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. The detailed description disclosed below, together with the accompanying drawings, is intended to describe exemplary embodiments of the present invention and is not intended to show the only embodiments in which the present invention can be practiced. To clearly describe the present invention in the drawings, parts that are not relevant to the description may be omitted, and the same reference numerals may be used throughout the specification for identical or similar components. Furthermore, in the embodiments of the present invention, terms including ordinal numbers such as "first," "second," etc. are used only to distinguish one component from another, and singular expressions include plural expressions unless the context clearly indicates otherwise.

[0029] FIG. 1 is a diagram illustrating a network system configured with a plurality of communication devices supporting RAPIEnet.

[0030] FIG. 1 shows an example of a network system 1, in which multiple communication devices 100 form a network using a combination of ring topology, line topology, and tree topology, and illustrates a RAPIEnet ring switch 10 that connects the ring topology network and the line topology network, and a general-purpose Ethernet switch 20 that connects the ring topology network and the tree topology network.

[0031] RAPIEnet, which is configured using two physical layers, can only be applied to networks with ring or line topologies. Therefore, in a control field where networks can only be configured with star or tree topologies (hereinafter also referred to as the first topology), RAPIEnet communication can be performed using a RAPIEnet ring switch 10 that supports the RAPIEnet protocol. However, the ring switch 10 is not suitable for configuring various topologies because it is limited in the number of ports it can accommodate, and the ring switch 10 itself is expensive, making it difficult to apply.

[0032] RAPIEnet, currently used in the industrial field, is configured to eliminate the UDP / IP layer to enable fast timing and real-time scheduling suitable for industrial control, and to communicate directly from the RAPIEnet Data Link layer to the application layer. Therefore, general-purpose Ethernet switches 20 that understand UDP / IP frames but cannot understand the RAPIEnet protocol cannot be used.

[0033] As shown in FIG. 1, the general-purpose Ethernet switch 20 connected to the ring switch 10 does not understand the RAPIEnet protocol, and communication devices configured in a tree topology cannot communicate with communication devices configured in a ring or line topology.

[0034] Hereinafter, the present invention will be described with respect to a communication device that uses a first communication method based on a data link hierarchy based on multiple Ethernet ports and can communicate with another communication device using a second communication method based on a data link hierarchy based on a single Ethernet port, where the first communication method can be RAPIEnet communication and the second communication method can be UDP / IP communication, and the first and second communication methods are connection-non-oriented communication methods.

[0035] In other words, we propose an invention that enables communication at the UDP / IP layer using the RAPIEnet protocol stack. In this case, RAPIEnet communication is possible using UDP / IP frames, and RAPIEnet networks can be configured in star or tree topologies using inexpensive, easy-to-use general-purpose Ethernet switches.

[0036] FIG. 2 is a diagram illustrating a RAPIEnet protocol stack according to an embodiment of the present invention.

[0037] The protocol stack 200 shown in FIG. 2 shows a protocol transmission path when the application being operated is a generic application, that is, a RAPIEnet application (real-time application).

[0038] More specifically, the protocol stack 200 includes a physical layer 210 , a RAPIEnet Data Link layer 220 , an IP layer 230 , a TCP / UDP layer 240 , a RAPIEnet Application layer 250 , and an Application layer 260 .

[0039] The physical layer 210 is a physical area where data such as frames or packets are digitized and sent from one node to an adjacent node, and defines protocols related to network standards such as LAN, WAN, and MAN. A communication device that supports RAPIEnet has two ports.

[0040] The RAPIEnet Data Link layer 220 calculates the hops to each communication device through a negotiation process, and acquires and manages information on the optimal route between communication devices and the network configuration. In general RAPIEnet communication, data is transmitted and received through a Real Time-Queue (RT-Q) 221, which has a high scheduling priority. According to one embodiment of the present invention, the RAPIEnet Data Link layer 220 may be a data link layer based on multiple Ethernet ports.

[0041] The IP layer 230, similar to the RAPIEnet Data Link layer 220, is a layer that determines the path that data should take to send it to the destination communication device. Although the IP layer 230 is shown in the protocol stack 200 as passing through the RAPIEnet Data Link layer 220, in reality, data sent from the IP layer 230 is transmitted to the physical layer 210 without modification through the NRT-Q (Non Real Time-Q) 222. In other words, there is no interdependence between the IP layer 230 and the RAPIEnet Data Link layer 220. However, the IP layer 230 manages a table that determines which port in the physical layer 210 to send and receive data to based on the address management system called the MAC address 223 of the RAPIEnet Data Link layer 220.

[0042] The TCP / UDP layer 240 is an area that defines the method of transmitting data. Through the TCP layer, a connection between communication devices is established and maintained while data is being sent and received in a connection-oriented manner, ensuring reliability. Through the UDP layer, unlike TCP, data is not divided into packets and reassembled, resulting in a faster data transmission speed. When exchanging data in a connectionless manner, data is sent and received unilaterally without going through the signal processing procedures of sending and receiving data.

[0043] In this case, the RAPIEnet message communication method uses a connection-non-oriented protocol rather than a connection-oriented protocol. Therefore, in the present invention, the IP layer is accessed using UDP, a connection-non-oriented protocol type. As a result, a UDP header is attached to data used by RAPIEnet applications, and a first topology network can be configured using a general-purpose Ethernet switch.

[0044] The RAPIEnet Application layer 250 is a data transmission layer similar to the TCP / UDP layer 240, and has a RAPIEnet DL interface (RAPIEnet DL I / F) 251 and a UDP interface (UDP I / F) 252 to access upper / lower layers. The RAPIEnet Application layer 250 can select one of the two interfaces to send and receive data.

[0045] Therefore, the present invention can implement two communication paths for RAPIEnet applications. One is a general RAPIEnet communication method, which transmits data to the RAPIEnet Data Link layer 220 through the RAPIEnet DL interface 251, and receives data from the RAPIEnet Data Link layer 220 through the RAPIEnet DL interface 251. The other is a transmission path to the IP layer 230, which is implemented in the present invention, and uses the UDP interface 252 to communicate with the IP layer 230.

[0046] The communication device 100 according to an embodiment of the present invention may attempt to communicate with another communication device using a first communication method, which is RAPIEnet communication, and if the communication fails, may attempt to communicate using a second communication method, which is UDP / IP communication. However, the communication device 100 is not limited thereto, and may communicate with another communication device using the first or second communication method selected by a user input.

[0047] The reason why the UDP interface 252 is used instead of the TCP interface is that RAPIEnet uses a connection-non-oriented protocol, as explained above in the TCP / UDP layer 240 .

[0048] When data passes through the UDP interface 252 of the RAPIEnet Application layer 250, the data will include header information related to the UDP interface, which allows the TCP / UDP layer 240 to identify the RAPIEnet Application data.

[0049] According to an embodiment of the present invention, when the communication device 100 communicates with another communication device using a second communication method, i.e., UDP / IP communication, the communication is performed using header information required for the second communication method. That is, RAPIEnet-based data can be communicated by adding header information related to a UDP interface. The header information related to a UDP interface is described in detail in FIG. 4.

[0050] The Application layer 260 is a layer that defines services for exchanging data between the sending and receiving sides, and includes general applications and RAPIEnet applications.

[0051] RAPIEnet applications include, for example, applications that perform data write / read functions in a client / server model, data input / output functions in a master / slave model, data sharing functions in a producer / consumer model, remote OS download functions, and various diagnostic functions.

[0052] RAPIEnet applications have the characteristic of operating at predictable times, whereas general applications cannot predict the timing of their operations. Therefore, RAPIEnet applications are used when real-time control of application operations is required, such as in an automobile production workplace where conveyor belts move sequentially.

[0053] According to one embodiment of the present invention, a RAPIEnet application in the Application layer 260 can communicate via the RAPIEnet Data Link layer 220 through the RAPIEnet DL interface 251 in the RAPIEnet Application layer 250, and can communicate via UDP / IP through the UDP interface 252.

[0054] In this way, since general-purpose Ethernet switches can understand the UDP protocol, it is possible to configure a RAPIEnet network in a tree or star topology using general-purpose Ethernet switches.

[0055] FIG. 3 is a diagram illustrating a RAPIEnet protocol stack according to an embodiment of the present invention.

[0056] The protocol stack 300 shown in this drawing differs from the protocol stack 200 shown in Fig. 2 in that it does not include the RAPIEnet Data Link layer 220. The IP layer 320, TCP / UDP layer 330, and application layer 350 have the same roles and functions as the layers in the protocol stack 200 shown in Fig. 2, so they should be understood by referring to this.

[0057] The protocol stack 300 of Figure 3 can be applied to communication devices that cannot implement the RAPIEnet Data Link layer 220. To implement the RAPIEnet Data Link layer 220, a hardware configuration that implements the functions of RT-Q 221 and NRT-Q 222 is required. However, communication devices that have difficulty implementing such hardware configuration, such as embedded devices like PCs and HMIs (Human Machine Interfaces), which can only perform conventional communications, cannot implement the RAPIEnet Data Link layer 220. Even in this case, as previously described with reference to Figure 2, the IP layer 230 is independent of the RAPIEnet Data Link layer 220 and determines the data transmission path using the MAC address 223, so the protocol stack 300 of Figure 3, in which the RAPIEnet Data Link layer 220 is removed, can be applied.

[0058] That is, even if a general communication device cannot implement the RAPIEnet Data Link layer 220, it can communicate with the RAPIEnet application in the Application layer 350 via the Ethernet MAC 310, IP layer 320, and UDP layer 330 through the UDP interface 341 of the RAPIEnet Application layer 340.

[0059] According to one embodiment of the present invention, even a general communication device that cannot implement the RAPIEnet Data Link layer 220 for RAPIEnet communication can send and receive data using a RAPIEnet application through the UDP interface 341, thereby providing flexibility in network configuration.

[0060] FIG. 4 is a diagram illustrating header information 400 related to a UDP interface according to an embodiment of the present invention.

[0061] RAPIEnet applications can select an effective communication method by utilizing the various functions of the RAPIEnet Data Link layer. Because RAPIEnet applications utilize the various transmission functions of the RAPIEnet Data Link layer, header information must be added to the UDP interface.

[0062] The header information includes six items: 1) Destination Address (based on the RAPIEnet standard), 2) Source Address (based on the RAPIEnet standard), 3) Destination SAP (Service Access Point) (based on the RAPIEnet standard), 4) Source SAP (Service Access Point) (based on the RAPIEnet standard), 5) Extension Data field (based on the RAPIEnet standard), and 6) Group Data field (based on the RAPIEnet standard). Below, we will look at each item in more detail with reference to Table 1, which lists the values ​​and descriptions.

[0063] 1)Destination Address(DST_addr) This field indicates the destination address of the node to which the frame is transmitted. In RAPIEnet, the destination address of a message can be set from 0x0000 to 0xFFFF as shown in Table 1. If the destination address is 0xFF, the destination MAC address field contains the ISO / IEC / IEEE 8802 3MAC address.

[0064] 2) Source Address (SRC_addr) This field represents the source address of the node where the frame originates.

[0065] 3)Destination SAP(Service Access Point) This field indicates the SAP of the DLE to which the DLPDU is transmitted, and the allowed value range is 0 to 65535.

[0066] 4)Source SAP(Service Access Point) This field indicates the SAP of the DLE where the DLPDU is generated, and the allowed value range is 0 to 65535.

[0067] 5) Extension Data area This field is present if the VoE bit in the Frame Control field is set to TRUE.

[0068] Group Mask Enable is a bit field that specifies whether the frame is accepted by the peer device when the frame is broadcast or multicast. If the value is set to TRUE, the Group Mask is activated on the peer device receiving the frame.

[0069] The Group Mask field uses a bit sequence to represent message reception options. When Group Mask Enable is set to TRUE, the Group Mask field is added in 4-octet increments (e.g., 4, 8, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 32 octets). Each bit represents a frame reception option for the corresponding DL entity identifier. 1 means TRUE for frame reception, 0 means FALSE. The first bit represents the frame reception option for the highest DL entity identifier.

[0070] The Extension type field indicates the type of the extension field. A value of 0x00 indicates an invalid extension type, and other values ​​are reserved for future use.

[0071] The Extension Length field indicates the length of the extension field. If Group Mask Enable is set to TRUE and Extension Type is set to 0x00, Extension Length specifies the length of the Group Mask field. If Group Mask Enable is set to FALSE and Extension Type is set to a value other than 0x00, Extension Length specifies the length of the extension field. If Group Mask Enable is set to TRUE and Extension Type is not set to 0x00, the first two octets specify the length of the Group Mask field, and the next two octets specify the extension type.

[0072] [Table 1]

[0073] FIG. 5 is a block diagram illustrating a configuration of a communication device 100 according to an embodiment of the present invention.

[0074] The input unit 110 includes at least one port for connecting the communication device 100 to another communication device, such as a RAPIEnet ring switch 10 or a general-purpose Ethernet switch 20. The input unit 110 also includes at least one input means for generating input data in response to a user input. The input unit 110 may include an input terminal, a button, a rotary switch, a keypad, a dome switch, a touch panel, a jog shuttle, a touch key, etc.

[0075] The communication unit 120 communicates with external devices such as other communication devices and external servers (not shown). To this end, the communication unit 120 can perform wireless communication such as 5th Generation communication (5G), Long Term Evolution-Advanced (LTE-A), Long Term Evolution (LTE), and Wireless Fidelity (Wi-Fi). The communication unit 120 can use wireless communication such as radio frequency (RF), Zigbee, Bluetooth, Wi-Fi, Ultra Wide Band (UWB), and Near Field Communication (NFC) as a communication method. The communication unit 120 can be embodied as a wireless communication module that performs wireless communication with an AP such as Wi-Fi, or a wireless communication module that performs one-to-one direct wireless communication such as Bluetooth.

[0076] The display unit 130 displays display data related to the operation of the communication device 100. The display unit 130 may include a liquid crystal display (LCD), a light emitting diode (LED) display, an organic light emitting diode (OLED) display, a micro electro mechanical systems (MEMS) display, and an electronic paper display. The display unit 130 may be combined with the input unit 110 and implemented as a touch screen.

[0077] The storage unit 140 stores an operating program for the communication device 100. The storage unit 140 includes non-volatile storage that can store data regardless of whether power is supplied, and volatile memory that loads data to be processed by the processor 150 and cannot store data unless power is supplied. Examples of storage include flash memory, hard disk drive (HDD), solid-state drive (SSD), and read-only memory (ROM), while examples of memory include buffers and random access memory (RAM).

[0078] The processor 150 can execute software such as a program to control at least one other component (e.g., hardware or software component) of the communication device 100 coupled to the processor 150, and can perform various data processing or calculations.

[0079] The processor 150 can configure data to be transmitted to other communication devices through a UDP interface based on the network configuration on the communication path connecting the communication device 100 and other communication devices, and can perform operations to transmit data to other communication devices using the communication path through the communication unit 120.

[0080] The processor 150 may identify header information included in data received from another communication device, and if the identified header information includes header information related to a UDP interface, may perform an operation of receiving data through the UDP interface.

[0081] FIG. 6 is a diagram illustrating a network system 600 configured with a plurality of communication devices supporting RAPIEnet according to an embodiment of the present invention.

[0082] A network system 600 according to an embodiment of the present invention is configured with a ring topology network and a tree topology network, and the two networks are connected to a ring switch 10 and a general-purpose Ethernet switch 20 connected to the ring switch 10. In this embodiment, a case will be described in which communication is performed between a first communication device 101 included in the ring topology network and a second communication device 102 included in the tree topology network. The first communication device 101 and the second communication device 102 are one of the communication devices 100 previously described in FIG. 5, and the configuration included in each communication device can be understood by referring to the description of FIG. 5.

[0083] In Figure 6, the first communication device 101 forms a ring topology, which is one of the RAPIEnet networks, and communicates using the protocol stack 200 of Figure 2. In the case of the second communication device 102, if it is a communication device that supports RAPIEnet, it can use the protocol stack 200 of Figure 2, but is not limited thereto, and if it is a communication device that performs general IP communication, it can use the protocol stack 300 of Figure 3. In other words, the second communication device 102 is a communication device that forms a tree topology network and does not necessarily have to be a RAPIEnet communication device with two physical ports.

[0084] When a network configured with at least one of a star topology and a tree topology is included on a communication path connecting the first communication device 101 and the second communication device 102, data must access the IP layer 230. That is, in order to send and receive data between communication devices on a star topology or a tree topology, the data must pass through a general-purpose Ethernet switch, and since a general-purpose Ethernet switch can understand an IP-based protocol, a modification of the data transmission protocol is required.

[0085] The first processor 151 of the first communication device 101 can access a RAPIEnet-based upper layer to receive data coming into the IP layer 230, and can use a UDP interface 252, which is a first interface that can access an IP-based lower layer to transmit RAPIEnet-based data using an IP-based protocol. In this case, the UDP interface 252 can exist in a RAPIEnet application layer 250. Referring to the protocol stack 200 of FIG. 2, the RAPIEnet-based upper layer refers to the RAPIEnet application layer 250 and application layer 260, and the IP-based lower layer refers to the TCP / UDP layer 240 and lower layers.

[0086] However, the first communication device 101 also communicates with other communication devices included in the RAPIEnet ring network, and can use a second interface, the RAPIEnet DL interface 251, to access upper layers of the RAPIEnet base and lower layers of the RAPIEnet base.

[0087] That is, the first processor 151 of the first communication device 101 can select one of the RAPIEnet DL interface 251 and the UDP interface 252 to access a lower layer in the RAPIEnet Application layer 250 of the protocol stack 200 and transmit data.

[0088] The first processor 150 of the first communication device 101 may configure data to be transmitted to the second communication device 102 through the UDP interface 252 based on the communication path with the second communication device 102. Alternatively, the first processor 150 of the first communication device 101 may identify whether or not a generic Ethernet switch 20 is present on the communication path and determine whether a path via the UDP interface 252 should be selected. The data configured through the UDP interface 252 includes header information related to the UDP interface previously described in FIG. 4.

[0089] The first processor 151 of the first communication device 101 may transmit RAPIEnet-based data including header information related to the UDP interface 252 to the second communication device 102 along a communication path with the second communication device 102 .

[0090] The second processor 152 of the second communication device 102 identifies header information included in the data received from the first communication device 101. If the identified header information includes header information related to the UDP interface 252, the second communication device 102 receives the data through the UDP interface 252.

[0091] More specifically, when the second communication device 102 uses the protocol stack 200 of Fig. 2, it receives data through the NRT-Q 222 of the RAPIEnet Data Link layer 220, the IP layer 230, the TCP / UDP layer 240, and the UDP interface 252 of the RAPIEnet Application layer 250. If the second communication device 102 is a device that performs general IP communication, such as a PC or embedded device, as described above, it can use the protocol stack 300 of Fig. 3 to communicate with a RAPIEnet application in the application layer 350 through the MAC layer 310, the IP layer 320, the UDP layer 330, and the UDP interface 341 of the RAPIEnet Application layer 340.

[0092] According to an embodiment of the present invention, a RAPIEnet application can be used without modification even in a network having a topology that does not allow existing RAPIEnet communication, eliminating the need for resources required for application development.Furthermore, a RAPIEnet application can be used without modification even in a communication device that does not support RAPIEnet communication, which is economical.

[0093] FIG. 7 is a diagram illustrating a network system 700 including a plurality of communication devices supporting RAPIEnet according to another embodiment of the present invention.

[0094] A network system 700 according to an embodiment of the present invention is configured with a line topology network and a tree topology network, and the two networks are connected to a general-purpose Ethernet switch 20. In this embodiment, a case will be described in which communication is performed between a first communication device 101 included in the line topology network and a second communication device 102 included in the tree topology network. The first communication device 101 and the second communication device 102 are one of the communication devices 100 previously described in FIG. 5, and the configuration included in each communication device can be understood by referring to the description of FIG. 5.

[0095] In FIG. 7, the first communication device 101 forms a line topology, which is one of the RAPIEnet networks, and communicates using the protocol stack 200 of FIG.

[0096] 7 is the same as in FIG. 6 except that the networks including the first communication device 101 are line and ring topologies, respectively. Therefore, overlapping points will be omitted and only additional content will be mentioned. Needless to say, the relevant content can also be supplementarily applied to the network system 600 in FIG. 6.

[0097] According to one embodiment of the present invention, four communication devices constituting a line topology establish a line network manager through a mutual negotiation process, where the line network manager may be a communication device located at either end of the four communication devices.

[0098] The line network manager ensures that communication devices send and receive RAPIEnet-based data only within the line network. This is because if the RAPIEnet protocol is transmitted through the generic Ethernet switch 20, the generic Ethernet switch 20 cannot understand it and may break or malfunction. Therefore, the line network manager only transmits data containing IP-based protocols, i.e., data containing header information related to the UDP interfaces 252 and 341, to the generic Ethernet switch 20.

[0099] At this time, the first communication device 101, which is the client side initiating the data communication, may have information in advance about which interface to use to transmit data, the RAPIEnet DL interface 251 or the UDP interface 252. This information may exist in the form of client side communication parameters, which can be set by the communication user (engineer).

[0100] On the other hand, when the second communication device 102, which is a server-side communication device, responds to data requested by a client, it can distinguish which interface, the RAPIEnet DL interface 251 or the UDP interface 252, the data was received through based on the header information contained in the received data, and can use this information to respond to the appropriate interface.

[0101] FIG. 8 is a diagram illustrating a network system 800 including a plurality of communication devices supporting RAPIEnet according to yet another embodiment of the present invention.

[0102] A network system 800 according to an embodiment of the present invention is configured as a tree topology network, and communication devices are connected to a general-purpose Ethernet switch 20. In this embodiment, a case will be described in which communication is performed between a first communication device 101 and a second communication device 102 included in the tree topology network. The first communication device 101 and the second communication device 102 are one of the communication devices 100 previously described in FIG. 5, and the configuration included in each communication device can be understood by referring to the description of FIG. 5.

[0103] In this embodiment, the first communication device 101 and the second communication device 102 may use the protocol stack 200 of Fig. 2 if they are communication devices that support RAPIEnet, but are not limited thereto and may use the protocol stack 300 of Fig. 3 if they are communication devices that perform general IP communication. In other words, the first communication device 101 and the second communication device 102 are communication devices that configure a tree topology network and are not necessarily RAPIEnet communication devices having two physical ports.

[0104] The first processor 151 of the first communication device 101 identifies a communication path connecting the first communication device 101 and the second communication device 102 for communicating with the second communication device 102 .

[0105] Since the first communication device 101 and the second communication device 102 communicate through the generic Ethernet switch 20 , the data must access the IP layer 230 .

[0106] The first processor 151 of the first communication device 101 can use a first interface, a UDP interface 252, to access a RAPIEnet-based upper layer and an IP-based lower layer. Alternatively, if the first communication device 101 is a device that performs general IP communication, such as a PC or an embedded device, it can use a UDP interface 341 of the protocol stack 300 of FIG. 3 to access a RAPIEnet-based upper layer and an IP-based lower layer.

[0107] The second processor 152 of the second communication device 102 identifies header information included in the data received from the first communication device 101. If the identified header information includes header information related to the UDP interface 252, the second communication device 102 receives the data through the UDP interface 252. If the second communication device 102 is a device that performs general IP communication, such as a PC or an embedded device, it can perform communication through the UDP interface 341 of the protocol stack 300 of FIG. 3.

[0108] According to an embodiment of the present invention, IP-based RAPIEnet communication is possible even between communication devices in which the RAPIEnet Application layer for RAPIEnet communication is not implemented.

Claims

1. In a communication device, Communications Department; When a network configured with a first topology including a star topology or a tree topology is included on a communication path connecting the communication device and another communication device, data is configured to be transmitted to the other communication device through a first interface for accessing a higher layer based on RAPIEnet (Real-time Automation Protocols for Industrial Ethernet) and a lower layer based on IP (Internet Protocol); a processor that transmits the data to the other communication device via the communication unit using the communication path.

2. the data is first data, The processor: When a communication path connecting the communication device and another communication device is configured in a second topology including a star topology or a tree topology, selecting one of the first interface or a second interface for accessing an upper layer based on the RAPIEnet and a lower layer based on the RAPIEnet; configuring second data to be transmitted to the other communication device via the selected first interface or the selected second interface; The communication device according to claim 1 , wherein the data is transmitted to the other communication device via the communication unit using the communication path.

3. the data is first data, The processor: Identifying header information included in third data received from the other communication device; The communication device of claim 1 , wherein the third data is received through the first interface if the header information includes header information related to the first interface.

4. The processor: The communication device of claim 1 , wherein the data is configured to include header information related to the first interface.

5. The communication device according to claim 4 , wherein the header information includes a Destination Address, a Source Address, a Destination Service Access Point (SAP), a Source SAP, an Extension Data area, and a Group Data area.

6. In a network system, a plurality of communication devices including a first communication device and a second communication device; the first communication device First Communications Department; When a network configured with a first topology including a star topology or a line topology is included on a communication path connecting the first communication device and the second communication device, data is configured to be transmitted to the second communication device through a first interface for accessing a higher layer based on RAPIEnet (Real-time Automation Protocols for Industrial Ethernet) and a lower layer based on IP (Internet Protocol); a first processor that transmits the data to the second communication device via the first communication unit using the communication path; the second communication device a second communication unit; and Identifying header information included in the data received from the first communication device; a second processor that receives the data through the first interface if the header information includes header information related to the first interface.

7. The first processor 7. The network system according to claim 6, wherein the data is configured to include header information relating to the first interface.

8. 8. The network system according to claim 7, wherein the header information includes a Destination Address, a Source Address, a Destination Service Access Point (SAP), a Source SAP, an Extension Data area, and a Group Data area.

9. The network system according to claim 6 , further comprising: at least one Ethernet switch on a communication path connecting the first communication device and the second communication device.

10. A communications device running a RAPIEnet application, comprising: Selecting either a RAPIEnet data link interface or a UDP interface depending on the topology of a communication path connecting other communication devices; The communication device configures data to be transmitted to the other communication device and performs communication using a first communication method based on RAPIEnet or a second communication method based on UDP / IP, in accordance with the selected interface.

11. The communication device according to claim 10, wherein when the communication device communicates with the other communication device in the second communication method, the communication device communicates using header information required for the second communication method.

12. 11. The communication device according to claim 10, wherein when the communication device exists in a network of a ring topology or a line topology and the other communication device exists in a network of a star topology or a tree topology, the communication device communicates with the other communication device using the second communication method.

13. The communication device according to claim 10, wherein the communication device attempts communication with the other communication device in the second communication method if communication with the other communication device in the first communication method fails.

14. The communication device according to claim 10, wherein the communication device communicates with the other communication device in the first communication method or the second communication method selected by a user input.

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