CN117459490A - Method and system for accessing dual-redundancy TTE (time to live) network by serial communication interface network layer - Google Patents

Abstract

The invention provides a method and a system for accessing a dual-redundancy TTE network by a serial communication interface network layer, comprising a hybrid network consisting of the dual-redundancy TTE network and the serial communication interface network; the hybrid network realizes communication between a TTE end system and serial port terminals and between different serial port terminals based on IP data packets, and comprises the following steps of S1: the interface conversion terminal is used as an end system to be accessed into a dual redundancy TTE network; step S2: the serial communication interface loads and transmits an IP data packet according to the IP address of the network layer; step S3: the interface conversion terminal receives and processes the IP data packet through the serial communication interface. The method and the system provided by the invention realize network layer protocol conversion and bidirectional data transmission between the TTE network and the serial communication interface network, have better flexibility and improve the efficiency of data transmission.

Description

Method and system for accessing dual-redundancy TTE (time to live) network by serial communication interface network layer

Technical Field

The invention relates to the technical field of network communication and field buses, in particular to a method and a system for accessing a serial communication interface network layer into a dual redundancy TTE network.

Background

The field bus is an industrial data bus which is rapidly developed in recent years, mainly solves the problems of digital communication among field devices such as intelligent instruments and meters, controllers, execution mechanisms and the like in industrial fields and information transmission between the field control devices and an advanced control system, and generally adopts the field bus to interconnect electronic devices, thereby having higher reliability, instantaneity and time response characteristics.

With the continuous expansion of application scenes, the problems of interconnection, intercommunication and interoperation among devices of different factories are difficult to solve, and the development and popularization and application of field bus technology are seriously hindered.

Time-triggered Ethernet (TTE) is excellent in synchronization precision, network scale, compatibility difficulty, complexity, realization cost and the like, is popular more and more, and is applied to the fields of new energy automobiles, aviation and aerospace. Five-layer protocols of a physical layer, a data link layer, a network layer, a transport layer and an application layer can be constructed based on the TTE technology. TTE supports three message mechanisms of Time-Triggered (TT for short), rate-Constrained (RC for short) and Best-Effort (BE for short), and TT and RC messages are key traffic.

The application of ethernet technology to industrial automation control has become one direction of field bus technology development. In order to meet the application requirements of high real-time performance, various technical solutions for improving the real-time performance and reliability of the Ethernet are proposed by various large companies and standardization organizations.

However, when TTE technology is applied, there may also be electronic devices in the system that employ conventional Fieldbus technology, such as serial communication interfaces for RS232, RS422, LVDS, etc. The serial communication interface has low realization cost, and if the serial communication interface is replaced by a TTE network interface, the equipment has high reconstruction cost and long reconstruction period. In order to balance the advancement of network technology and the system development SWaP-C overhead, the interconnection and interworking between different transmission interface devices are generally realized by adopting an interface conversion mode.

The conventional interface conversion between the common Ethernet and the serial communication interface is generally customized based on specific application scenes and requirements, lacks the generalized design of protocol conversion and bidirectional data transmission, and does not well utilize the advantages of IP protocol whole network identification and addressing;

when the TTE network is popularized and applied, the compatibility problem of the traditional interface with the original equipment is necessarily faced, a generalized protocol conversion method of the TTE network and a serial communication interface is not available at present, and a reliability guarantee mechanism of TTE network TT, RC and BE messages is required to BE fully utilized.

In the chinese patent document with publication number CN105991384B, a space ethernet communication method compatible with time triggered ethernet and 1553B is disclosed, which includes transmitting three data frames with different priorities by using a time triggered compatible protocol architecture: command corresponding data, IT application data, and time trigger data. However, all three frames adopt standard ethernet frame formats, which cannot solve the above problems.

In the chinese patent document with publication number CN110417630a, a time triggered ethernet switching device and method compatible with 1553B bus is disclosed, comprising: 1553B bus processing module and time triggering Ethernet exchange module; the implementation method comprises the following steps: decoding data sent by 1553B bus equipment into 1553B received information and caching, converting the 1553B received information into a time triggered Ethernet data frame and forwarding the time triggered Ethernet data frame to a corresponding destination port; and forwarding the data frame sent by the time-triggered Ethernet end system, converting the data frame sent to the 1553B bus into a 1553B sending message, caching the 1553B sending message, and encoding and sending the 1553B sending message to the 1553B bus. However, blocking may be caused during transmission, resulting in degradation of quality of service of 1553B command response data, and the transmission is not flexible enough, so that the document cannot solve the above problem.

In the chinese patent document with publication number CN113949600B, a method and apparatus for accessing a 1553B bus to a time trigger network are disclosed, including transmitting data from the 1553B bus to the time trigger network and transmitting data from the time trigger network to the 1553B bus; the 1553B bus sends data to a time triggered network, comprising the following steps: acquiring interrupt and reading 1553B data from a 1553B bus, performing frame format conversion on the 1553B data, storing the converted data into an uplink FIFO and sending the data in the uplink FIFO to a time triggering network; the time triggered network sending data to the 1553B bus comprises the following steps: receiving data from the time triggered network and checking, performing frame format conversion on the received data, storing the converted data in the downstream FIFO and transmitting the data in the downstream FIFO to the 1553B bus. But may also cause congestion during transmission, resulting in degradation of quality of service of 1553B command response data, and the transmission is not flexible enough, so that the document cannot solve the above problem.

In chinese patent document with publication number CN103200195a, a conversion device and a conversion method for converting multiple serial protocols into ethernet communications are disclosed, where the device includes serial port communication equipment, embedded equipment, computer monitoring software, serial communication data lines, and ethernet communication data lines. The method comprises the following steps: starting S1, initializing S2, and sending a request S3 to all devices; the network port receives the TCP data packet S4, analyzes the TCP data packet S5, reads SDRAM data S6, forms a TCP data packet S7 and sends the TCP data packet S7 to the Ethernet port S8; is the serial port connected to RTU packet S9, checked correctly? S10, if yes, entering an analysis RTU data packet S11, taking out data S12 and storing the data into an SDRAMS13; if not, return to serial port to RTU packet S9. Finally, the process ends S14. However, the method adopted in this document cannot meet the technical requirements such as high real-time performance, and thus the above-mentioned problems cannot be solved.

In the chinese patent document with publication number CN105610876B, an industrial control automation network communication protocol converter and a communication protocol conversion method are disclosed, where the communication protocol converter includes a microprocessor, an upper port interface expansion circuit, a lower port interface expansion circuit, a memory and a power supply circuit; the upper interface expanding circuit comprises a serial communication interface, an Ethernet interface, a hardware protocol stack chip, a software protocol stack chip and a change-over switch for switching the hardware protocol stack chip and the software protocol stack chip to communicate with an upper computer, wherein the serial communication interface realizes the connection of the microprocessor and a Modbus network, and the Ethernet interface realizes the connection of the microprocessor and an industrial Ethernet; the lower port interface expanding circuit comprises a plurality of serial communication interfaces in one-to-one correspondence communication connection with a plurality of lower computers. However, the document has the defects of inflexibility, higher error rate, slower transmission rate and the like, and cannot meet the requirements of a modern industrial control system for different application environments, and the problems cannot be solved.

In chinese patent document with publication number CN109510746a, a data transmission method and a transmission device are disclosed, including a data recording system obtaining a first ethernet packet to be sent to a locomotive protection memory; converting the first ethernet packet into a first universal serial bus packet; and transmitting the first universal serial bus data packet to the locomotive protection memory through the universal serial bus interface. However, the data transmission method adopted in this document is single and not flexible enough, and thus the above-mentioned problems cannot be solved.

In chinese patent document with publication number CN106506347a, a multiprotocol data communication gateway device for an air traffic control system is disclosed, which comprises a chassis, a system main processor module disposed inside the chassis, and an intra-pair communication module and an external communication module embedded in a side wall of the chassis; the intra-pair communication module and the outer-pair communication module are connected with the system main processor module. However, the document has various bus types and various protocol types in data communication, so that standards are not uniform and cannot be compatible, and the problems cannot be solved.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a method and a system for accessing a dual redundancy TTE network by a serial communication interface network layer.

The method for accessing the dual-redundancy TTE network by the serial communication interface network layer comprises a hybrid network consisting of the dual-redundancy TTE network and the serial communication interface network; the dual redundancy TTE network comprises an end system; the serial communication interface network comprises an interface conversion terminal and a serial port terminal connected with the interface conversion terminal; the hybrid network realizes communication between a TTE end system and serial port terminals and between different serial port terminals based on IP data packets, and comprises the following steps:

Step S1: the interface conversion terminal is used as an end system to be accessed into a dual redundancy TTE network;

step S2: the serial communication interface loads and transmits an IP data packet according to the IP address of the network layer;

step S3: the interface conversion terminal receives and processes the IP data packet through the serial communication interface.

Preferably, the IP address includes a subnet number field and a terminal number field;

the subnet number field defines a subnet number for the TTE network, and defines a subnet number for each interface conversion terminal and a serial port terminal connected with the interface conversion terminal; the subnet numbers are unique in the same network, and the subnet numbers are reused among different networks;

defining a bit in the terminal number field as a main and standby identification bit, defining a terminal number for each end system of the TTE network, and distinguishing the two end systems of the main and standby redundancy through the main and standby identification bit; defining a terminal number for each serial port terminal of the serial communication interface network, and distinguishing the two serial port terminals with main and standby redundancy through main and standby identification bits; the interface conversion terminal is provided with a terminal number of the TTE network and a terminal number of the serial communication interface network at the same time; the terminal numbers are unique in the same sub-network, and the terminal numbers are reused in different sub-networks.

Preferably, if the data transmitting source terminal and the receiving destination terminal are in the same subnet, the subnet numbers of the source IP address and the destination IP address fields in the packet header of the IP data packet are assigned to fixed characteristic values; otherwise, the subnet number of the source IP address field in the IP data packet header is the subnet number of the transmitting end, and the subnet number of the destination IP address field is the subnet number of the receiving end.

Preferably, the step S2 includes the following substeps:

step S2.1: the source IP address field terminal number in the IP data packet header is the terminal number of the transmitting end serial port terminal, and the destination IP address field terminal number is the terminal number of the receiving end serial port terminal, the terminal number of the end system or the terminal number of the interface conversion terminal;

step S2.2: if the IP data packet is required to be forwarded to a receiving end through a TTE network, distinguishing best effort traffic and key traffic through a packet head stream category field of the IP data packet; if the key flow is adopted, the VLID is transmitted to the interface conversion terminal through the flow label field; if the best effort traffic is adopted, the flow label field is assigned to a fixed characteristic value;

step S2.3: when the end system sends an IP data packet, the terminal number of a source IP address field in the packet header is the terminal number of the sending end system; the terminal number of the destination IP address field is the terminal number of the receiving end serial port terminal, the terminal number of the end system or the terminal number of the interface conversion terminal;

Step S2.4: after the serial port terminal or the terminal system bears the IP data packet, judging the subnet number and the terminal number of the destination IP address field in the packet head of the IP data packet; if the subnet number is a local subnet number or a fixed characteristic value, and the terminal number is a local terminal number, further analyzing the IP data packet; otherwise, discarding the IP data packet and reporting the error.

Preferably, the step S3 includes the following substeps:

step S3.1: if the subnet number field of the target IP address is the subnet number or the fixed characteristic value of the serial communication interface network where the interface conversion terminal is located, further judging the number field of the target terminal; if the number of the target terminal is the number of the local terminal, the interface conversion terminal receives and analyzes the IP data packet; if the number of the target terminal is not the local terminal number, outputting the IP data packet through the corresponding port according to the terminal number and the serial communication output port mapping table;

step S3.2: if the destination IP address subnet number field is a subnet number of the TTE network, further determining a flow class field and a destination terminal number field: if the flow class is best effort flow, the TTE network terminal number and the MAC address mapping table are searched according to the destination terminal number field to determine the MAC address of the receiving end system, the IP data packet is packaged into an MAC frame, the source MAC address is the MAC address of the transmitting interface conversion terminal, and the destination MAC address is the MAC address of the receiving end system of the TTE network; if the flow type is key flow, taking the flow label field as data to transmit VL ID, encapsulating the IP data packet into an MAC frame, converting the terminal MAC address by taking the source MAC address as a transmitting interface, and taking the virtual link of the destination MAC address as VL ID;

Step S3.3: if the number of the target IP address subnet cannot be correctly addressed, discarding the IP data packet and reporting errors;

step S3.4: the interface conversion terminal receives the MAC frame through the TTE network, analyzes the MAC frame to obtain an IP data packet, and further judges a target terminal number field if the target IP address subnet number field is a subnet number or a fixed characteristic value of the TTE network where the interface conversion terminal is located; if the terminal number is the local terminal number, the interface conversion terminal receives and analyzes the IP data packet; if the terminal number is not the local terminal number, outputting the IP data packet through the corresponding port according to the terminal number and the serial communication output port mapping table.

Preferably, the interface conversion terminal establishes a mapping table of serial communication interface network subnet numbers and TTE network terminal numbers, a mapping table of TTE network terminal numbers and MAC addresses, and a mapping table of terminal numbers and serial communication output ports;

the mapping table of serial communication interface network subnet numbers and TTE network terminal numbers comprises: the TTE network terminal number is the TTE network terminal number of the interface conversion terminal, and the serial communication interface network subnet number is the subnet number defined by the interface conversion terminal and the serial port terminal connected with the interface conversion terminal;

The TTE network terminal number and MAC address mapping table comprises: the MAC address is the MAC address of the TTE network end system and the interface conversion module, and the TTE network terminal number is the terminal number of the TTE network end system and the interface conversion module;

the terminal number and serial communication output port mapping table includes: the serial communication output port is a serial communication interface address for outputting data from the interface conversion terminal to the serial port terminal, and the terminal number is the serial communication interface network terminal number of the conversion terminal.

Preferably, in the serial communication interface network, if a direct communication link exists between two serial terminals, IP data packets are directly sent, received and processed between the two serial terminals based on the serial terminal IP address definition.

Preferably, the serial communication interface between the interface conversion terminal and the serial port terminal supports a connection mode of one-to-two, two-to-one, one-to-one and two-to-two, and supports asynchronous serial transmission and synchronous serial transmission.

Preferably, the dual redundancy TTE network further comprises a switch; and the plurality of switches form a TTE switching network, and the main and standby redundant end systems are respectively and directly connected with a group of main and standby redundant switches in the switching network through Ethernet links.

The system for accessing the dual-redundancy TTE network by the serial communication interface network layer comprises a hybrid network consisting of the dual-redundancy TTE network and the serial communication interface network; the dual redundancy TTE network comprises an end system; the serial communication interface network comprises an interface conversion terminal and a serial port terminal connected with the interface conversion terminal; the hybrid network realizes communication between a TTE end system and serial port terminals and between different serial port terminals based on IP data packets, and comprises the following modules:

module M1: the interface conversion terminal is used as an end system to be accessed into a dual redundancy TTE network;

module M2: the serial communication interface loads and transmits an IP data packet according to the IP address of the network layer;

module M3: the interface conversion terminal receives and processes the IP data packet through the serial communication interface.

Preferably, the IP address includes a subnet number field and a terminal number field;

the subnet number field defines a subnet number for the TTE network, and defines a subnet number for each interface conversion terminal and a serial port terminal connected with the interface conversion terminal; the subnet numbers are unique in the same network, and the subnet numbers are reused among different networks;

defining a bit in the terminal number field as a main and standby identification bit, defining a terminal number for each end system of the TTE network, and distinguishing the two end systems of the main and standby redundancy through the main and standby identification bit; defining a terminal number for each serial port terminal of the serial communication interface network, and distinguishing the two serial port terminals with main and standby redundancy through main and standby identification bits; the interface conversion terminal is provided with a terminal number of the TTE network and a terminal number of the serial communication interface network at the same time; the terminal numbers are unique in the same sub-network, and the terminal numbers are reused in different sub-networks.

Preferably, if the data transmitting source terminal and the receiving destination terminal are in the same subnet, the subnet numbers of the source IP address and the destination IP address fields in the packet header of the IP data packet are assigned to fixed characteristic values; otherwise, the subnet number of the source IP address field in the IP data packet header is the subnet number of the transmitting end, and the subnet number of the destination IP address field is the subnet number of the receiving end.

Preferably, the module M2 comprises the following sub-modules:

module M2.1: the source IP address field terminal number in the IP data packet header is the terminal number of the transmitting end serial port terminal, and the destination IP address field terminal number is the terminal number of the receiving end serial port terminal, the terminal number of the end system or the terminal number of the interface conversion terminal;

module M2.2: if the IP data packet is required to be forwarded to a receiving end through a TTE network, distinguishing best effort traffic and key traffic through a packet head stream category field of the IP data packet; if the key flow is adopted, the VLID is transmitted to the interface conversion terminal through the flow label field; if the best effort traffic is adopted, the flow label field is assigned to a fixed characteristic value;

module M2.3: when the end system sends an IP data packet, the terminal number of a source IP address field in the packet header is the terminal number of the sending end system; the terminal number of the destination IP address field is the terminal number of the receiving end serial port terminal, the terminal number of the end system or the terminal number of the interface conversion terminal;

Module M2.4: after the serial port terminal or the terminal system bears the IP data packet, judging the subnet number and the terminal number of the destination IP address field in the packet head of the IP data packet; if the subnet number is a local subnet number or a fixed characteristic value, and the terminal number is a local terminal number, further analyzing the IP data packet; otherwise, discarding the IP data packet and reporting the error.

Preferably, the module M3 comprises the following sub-modules:

module M3.1: if the subnet number field of the target IP address is the subnet number or the fixed characteristic value of the serial communication interface network where the interface conversion terminal is located, further judging the number field of the target terminal; if the number of the target terminal is the number of the local terminal, the interface conversion terminal receives and analyzes the IP data packet; if the number of the target terminal is not the local terminal number, outputting the IP data packet through the corresponding port according to the terminal number and the serial communication output port mapping table;

module M3.2: if the destination IP address subnet number field is a subnet number of the TTE network, further determining a flow class field and a destination terminal number field: if the flow class is best effort flow, the TTE network terminal number and the MAC address mapping table are searched according to the destination terminal number field to determine the MAC address of the receiving end system, the IP data packet is packaged into an MAC frame, the source MAC address is the MAC address of the transmitting interface conversion terminal, and the destination MAC address is the MAC address of the receiving end system of the TTE network; if the flow type is key flow, taking the flow label field as data to transmit VL ID, encapsulating the IP data packet into an MAC frame, converting the terminal MAC address by taking the source MAC address as a transmitting interface, and taking the virtual link of the destination MAC address as VL ID;

Module M3.3: if the number of the target IP address subnet cannot be correctly addressed, discarding the IP data packet and reporting errors;

module M3.4: the interface conversion terminal receives the MAC frame through the TTE network, analyzes the MAC frame to obtain an IP data packet, and further judges a target terminal number field if the target IP address subnet number field is a subnet number or a fixed characteristic value of the TTE network where the interface conversion terminal is located; if the terminal number is the local terminal number, the interface conversion terminal receives and analyzes the IP data packet; if the terminal number is not the local terminal number, outputting the IP data packet through the corresponding port according to the terminal number and the serial communication output port mapping table.

Preferably, the interface conversion terminal establishes a mapping table of serial communication interface network subnet numbers and TTE network terminal numbers, a mapping table of TTE network terminal numbers and MAC addresses, and a mapping table of terminal numbers and serial communication output ports;

the mapping table of serial communication interface network subnet numbers and TTE network terminal numbers comprises: the TTE network terminal number is the TTE network terminal number of the interface conversion terminal, and the serial communication interface network subnet number is the subnet number defined by the interface conversion terminal and the serial port terminal connected with the interface conversion terminal;

The TTE network terminal number and MAC address mapping table comprises: the MAC address is the MAC address of the TTE network end system and the interface conversion module, and the TTE network terminal number is the terminal number of the TTE network end system and the interface conversion module;

the terminal number and serial communication output port mapping table includes: the serial communication output port is a serial communication interface address for outputting data from the interface conversion terminal to the serial port terminal, and the terminal number is the serial communication interface network terminal number of the conversion terminal.

Preferably, in the serial communication interface network, if a direct communication link exists between two serial terminals, IP data packets are directly sent, received and processed between the two serial terminals based on the serial terminal IP address definition.

Preferably, the serial communication interface between the interface conversion terminal and the serial port terminal supports a connection mode of one-to-two, two-to-one, one-to-one and two-to-two, and supports asynchronous serial transmission and synchronous serial transmission.

Preferably, the dual redundancy TTE network further comprises a switch; and the plurality of switches form a TTE switching network, and the main and standby redundant end systems are respectively and directly connected with a group of main and standby redundant switches in the switching network through Ethernet links.

Compared with the prior art, the invention has the following beneficial effects:

1. the method and the system provided by the invention realize network layer protocol conversion and bidirectional data transmission between the TTE network and the serial communication interface network, have better flexibility and improve the efficiency of data transmission.

2. The method and the system provided by the invention realize the whole network equipment, path identification and addressing of the serial communication interface and the TTE network through the definition of the packet header field of the IP data packet.

3. The serial communication data in the invention can BE transmitted through TT, RC and BE messages of the TTE network, fully utilizes a data transmission reliability guarantee mechanism of the TTE technology, and has wide application range in the technical fields of network communication and field buses.

Other advantages of the present invention will be set forth in the description of specific technical features and solutions, by which those skilled in the art should understand the advantages that the technical features and solutions bring.

Drawings

Other features, objects and advantages of the present invention will become more apparent upon reading of the detailed description of non-limiting embodiments, given with reference to the accompanying drawings in which:

Fig. 1 is a schematic diagram of a method for accessing a dual redundancy TTE network by a network layer of a serial communication interface according to an embodiment of the present invention.

Fig. 2 is a flowchart of a serial port terminal sending an IP packet in an embodiment of the present invention.

Fig. 3 is a flowchart of an interface conversion terminal receiving and processing an IP packet through a serial communication interface according to an embodiment of the present invention.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the present invention, but are not intended to limit the invention in any way. It should be noted that variations and modifications could be made by those skilled in the art without departing from the inventive concept. These are all within the scope of the present invention.

The invention provides a method for accessing a dual-redundancy TTE network by a serial communication interface network layer, which comprises a hybrid network consisting of the dual-redundancy TTE network and the serial communication interface network. The dual redundancy TTE network comprises an end system, and the serial communication interface network comprises an interface conversion terminal and a serial port terminal connected with the interface conversion terminal; the hybrid network realizes communication between the TTE end system and the serial port terminals and between different serial port terminals based on the IP data packet.

Firstly, an interface conversion terminal is used as an end system to access a dual redundancy TTE network. The interface conversion terminal is not only a type of end system of the TTE network, but also a type of serial port terminal of the serial communication interface network, and network layer protocol conversion and bidirectional data transmission between the TTE network and the serial communication interface network are realized by the interface conversion terminal.

Referring to fig. 1, the dual redundant TTE network further includes a switch. End system 1-primary and end system 1-backup represent primary and backup redundant end systems; switch 1-master and switch 1-slave, switch N-master and switch N-slave represent switches that are redundant to master and slave; a TTE switching network is formed by a plurality of main and standby redundant switches, and the main and standby redundant end systems are respectively and directly connected with a group of main and standby redundant switches in the switching network through Ethernet links.

Serial port terminal 11-primary and serial port terminal 11-standby, serial port terminal 1K-primary and serial port terminal 1K-standby represent primary and standby redundant serial port terminals. The serial port terminal 11-main and serial port terminal 11-standby, the serial port terminal 1K-main and serial port terminal 1K-standby are respectively connected with the interface conversion terminal 1-main and interface conversion terminal 1-standby through serial port communication links, such as RS422, LVDS interfaces, and the like.

Then, the serial port terminal can send and receive the IP data packet through the serial communication interface, and the end system can send and receive the IP data packet through the TTE network.

Referring to fig. 1 and 2, when the serial port terminal sends an IP packet, it is necessary to determine the position of the data receiving end first, and assignment rules of packet header fields of IP packets of different receiving ends are also different.

The source IP address field terminal number in the IP data packet header is the terminal number of the transmitting end serial port terminal, and the destination IP address field terminal number is the terminal number of the receiving end serial port terminal, the terminal number of the end system or the terminal number of the interface conversion terminal.

If the IP data packet needs to be forwarded to the receiving end through the TTE network, the best effort traffic and the key traffic are distinguished through the packet head stream class field of the IP data packet. If the key flow is adopted, the VLID is transmitted to the interface conversion terminal through the flow label field; if best effort traffic is employed, the flow label field is assigned a fixed characteristic value.

When the serial port terminal sends the IP data packet, if the IP data packet needs to be forwarded to the receiving end through the TTE network, for example, the serial port terminal 11-host sends the data to the serial port terminal 21-host through the TTE network, the best effort traffic and the key traffic are distinguished through the packet header stream class field of the IP data packet. If the key flow is adopted, the VL ID (virtual link number) is transmitted to an interface conversion terminal through a flow label field; if best effort traffic is employed, the flow label field is assigned a fixed characteristic value. Critical traffic includes TT, RC and best effort traffic is BE messages.

When the end system sends the IP data packet, the terminal number of the source IP address field in the IP data packet header is the terminal number of the sending end system. The terminal number of the destination IP address field is the terminal number of the receiving end serial port terminal, the terminal number of the end system or the terminal number of the interface conversion terminal. When MAC frames are assembled, IP packets may be transmitted over both best effort traffic and critical traffic.

After the serial port terminal or the terminal system bears the IP data packet, the subnet number and the terminal number of the destination IP address field in the packet head of the IP data packet are judged. If the subnet number is a local subnet number or a fixed characteristic value, and the terminal number is a local terminal number, further analyzing the IP data packet; otherwise, discarding the IP data packet and reporting the error.

Wherein, the IP address includes:

subnet number field: a subnet number is defined for the TTE network, and a subnet number is defined for each interface conversion terminal and serial port terminal connected thereto. The subnet number is unique in the same network, and can be reused among different networks.

Terminal number field: defining a bit as a main and standby identification bit, defining a terminal number for each end system of the TTE network, and distinguishing the two end systems of the main and standby redundancy through the main and standby identification bit. A terminal number is defined for each serial port terminal of the serial communication interface network, and the two serial port terminals with the main and standby redundancies are distinguished through the main and standby identification bits. The interface conversion terminal has the terminal number of the TTE network and the terminal number of the serial communication interface network at the same time, the terminal number is unique in the same subnet, and the terminal number can be reused in different subnets.

If the data transmitting source end and the receiving destination end are in the same subnet, the subnet numbers of the source IP address and the destination IP address fields in the IP data packet header are given a fixed characteristic value, such as full FF. Otherwise, the subnet number of the source IP address field in the IP data packet header is the subnet number of the transmitting end, and the subnet number of the destination IP address field is the subnet number of the receiving end.

Finally, the interface conversion terminal can send and receive IP data packets through the serial communication interface, and can also send and receive IP data packets through the TTE network.

Specifically, referring to fig. 3, it is shown that:

if the subnet number field of the target IP address is the subnet number or the fixed characteristic value of the serial communication interface network where the interface conversion terminal is located, further judging the number field of the target terminal; if the number of the target terminal is the number of the local terminal, the interface conversion terminal receives and analyzes the IP data packet; if the destination terminal number is not the local terminal number, outputting the IP data packet through the corresponding port according to the terminal number and the serial communication output port mapping table.

If the destination IP address subnet number field is a subnet number of the TTE network, further determining a flow class field and a destination terminal number field:

If the flow class is best effort flow, the TTE network terminal number and the MAC address mapping table are searched according to the destination terminal number field to determine the MAC address of the receiving end system, the IP data packet is packaged into an MAC frame, the source MAC address is the MAC address of the transmitting interface conversion terminal, and the destination MAC address is the MAC address of the receiving end system of the TTE network.

If the flow type is the key flow, the flow label field is used as data to transmit the VL ID, the IP data packet is encapsulated into an MAC frame, the source MAC address is the MAC address of the transmitting interface conversion terminal, and the virtual link of the destination MAC address is the VL ID.

If the subnet number of the destination IP address cannot be correctly addressed, the IP data packet is discarded and the error is reported.

The interface conversion terminal receives the MAC frame through the TTE network, analyzes the MAC frame to obtain an IP data packet, and further judges the number field of the target terminal if the number field of the subnet of the target IP address is the subnet number or the fixed characteristic value of the TTE network where the interface conversion terminal is located.

If the terminal number is the local terminal number, the interface conversion terminal receives and analyzes the IP data packet; if the terminal number is not the local terminal number, outputting the IP data packet through the corresponding port according to the terminal number and the serial communication output port mapping table.

The interface conversion terminal establishes:

mapping table of serial communication interface network subnet number and TTE network terminal number: the TTE network terminal number is the TTE network terminal number of the interface conversion terminal, and the serial communication interface network subnet number is the subnet number defined by the interface conversion terminal and the serial port terminal connected with the interface conversion terminal.

TTE network terminal number and MAC address mapping table: the MAC address is the MAC address of the TTE network end system and the interface conversion module, and the TTE network terminal number is the terminal number of the TTE network end system and the interface conversion module.

Terminal number and serial communication output port mapping table: the serial communication output port is a serial communication interface address for outputting data from the interface conversion terminal to the serial port terminal, and the terminal number is the serial communication interface network terminal number of the conversion terminal.

In the serial communication interface network, if a direct communication link exists between two serial terminals, the transmission, the reception and the processing of the IP data packet are directly performed between the two serial terminals based on the definition of the IP address of the serial terminal.

The serial communication interface between the interface conversion terminal and the serial port terminal supports a connection mode of one-to-two, two-to-one, one-to-one and two-to-two, so as to adapt to the redundancy backup requirements of the communication links under the single redundancy serial port terminal and the dual redundancy serial port terminal, and the distinction of the dual redundancy terminals is carried out through the main and standby identification bits in the terminal number field, so that the serial communication interface has better flexibility.

The serial communication interface may also support asynchronous serial transmission, synchronous serial transmission. In synchronous serial transmission, a clock line, a data line, a gate line, and the like are defined as a set corresponding to a certain serial communication output port.

The invention also provides a system for accessing the dual-redundancy TTE network by the serial communication interface network layer, which can be realized by executing the flow steps of the method for accessing the dual-redundancy TTE network by the serial communication interface network layer, namely, the method for accessing the dual-redundancy TTE network by the serial communication interface network layer can be understood as a preferred implementation mode of the system for accessing the dual-redundancy TTE network by the serial communication interface network layer by a person skilled in the art.

Specifically, the method comprises the following modules:

module M1: and accessing the interface conversion terminal as an end system into the dual-redundancy TTE network.

Module M2: the serial communication interface carries and transmits IP data packets according to the IP address of the network layer:

the source IP address field terminal number in the IP data packet header is the terminal number of the transmitting end serial port terminal, and the destination IP address field terminal number is the terminal number of the receiving end serial port terminal, the terminal number of the end system or the terminal number of the interface conversion terminal.

If the IP data packet needs to be forwarded to the receiving end through the TTE network, the best effort traffic and the key traffic are distinguished through the packet head stream class field of the IP data packet. If the key flow is adopted, the VLID is transmitted to the interface conversion terminal through the flow label field; if best effort traffic is employed, the flow label field is assigned a fixed characteristic value.

When the end system sends the IP data packet, the terminal number of the source IP address field in the packet head is the terminal number of the sending end system. The terminal number of the destination IP address field is the terminal number of the receiving end serial port terminal, the terminal number of the end system or the terminal number of the interface conversion terminal.

After the serial port terminal or the terminal system bears the IP data packet, judging the subnet number and the terminal number of the target IP address field in the packet head of the IP data packet, and if the subnet number is a local subnet number or a fixed characteristic value and the terminal number is a local terminal number, further analyzing the IP data packet; otherwise, discarding the IP data packet and reporting the error.

Wherein, the IP address includes:

subnet number field: a subnet number is defined for the TTE network, and a subnet number is defined for each interface conversion terminal and serial port terminal connected thereto. The subnet number is unique in the same network, and can be reused among different networks.

Terminal number field: defining a bit as a main and standby identification bit, defining a terminal number for each end system of the TTE network, and distinguishing the two end systems of the main and standby redundancy through the main and standby identification bit. A terminal number is defined for each serial port terminal of the serial communication interface network, and the two serial port terminals with the main and standby redundancies are distinguished through the main and standby identification bits. The interface conversion terminal has the terminal number of the TTE network and the terminal number of the serial communication interface network at the same time, the terminal number is unique in the same subnet, and the terminal number can be reused in different subnets.

If the data transmitting source terminal and the receiving destination terminal are in the same subnet, the subnet numbers of the source IP address and the destination IP address fields in the IP data packet header are assigned to fixed characteristic values; otherwise, the subnet number of the source IP address field in the IP data packet header is the subnet number of the transmitting end, and the subnet number of the destination IP address field is the subnet number of the receiving end.

Module M3: the interface conversion terminal receives and processes the IP data packet through the serial communication interface:

if the subnet number field of the destination IP address is a subnet number or a fixed characteristic value of the serial communication interface network where the interface conversion terminal is located, further judging the number field of the destination terminal:

If the number of the target terminal is the number of the local terminal, the interface conversion terminal receives and analyzes the IP data packet; if the destination terminal number is not the local terminal number, outputting the IP data packet through the corresponding port according to the terminal number and the serial communication output port mapping table.

If the destination IP address subnet number field is a subnet number of the TTE network, further determining a flow class field and a destination terminal number field:

if the flow class is best effort flow, the TTE network terminal number and the MAC address mapping table are searched according to the destination terminal number field to determine the MAC address of the receiving end system, the IP data packet is packaged into an MAC frame, the source MAC address is the MAC address of the transmitting interface conversion terminal, and the destination MAC address is the MAC address of the receiving end system of the TTE network.

If the flow type is the key flow, the flow label field is used as data to transmit the VL ID, the IP data packet is encapsulated into an MAC frame, the source MAC address is the MAC address of the transmitting interface conversion terminal, and the virtual link of the destination MAC address is the VL ID.

If the subnet number of the destination IP address cannot be correctly addressed, the IP data packet is discarded and the error is reported.

The interface conversion terminal receives the MAC frame through the TTE network, analyzes the MAC frame to obtain an IP data packet, and further judges the number field of the target terminal if the number field of the subnet of the target IP address is the subnet number or the fixed characteristic value of the TTE network where the interface conversion terminal is located:

If the terminal number is the local terminal number, the interface conversion terminal receives and analyzes the IP data packet; if the terminal number is not the local terminal number, outputting the IP data packet through the corresponding port according to the terminal number and the serial communication output port mapping table.

The interface conversion terminal establishes:

mapping table of serial communication interface network subnet number and TTE network terminal number: the TTE network terminal number is the TTE network terminal number of the interface conversion terminal, and the serial communication interface network subnet number is the subnet number defined by the interface conversion terminal and the serial port terminal connected with the interface conversion terminal.

TTE network terminal number and MAC address mapping table: the MAC address is the MAC address of the TTE network end system and the interface conversion module, and the TTE network terminal number is the terminal number of the TTE network end system and the interface conversion module.

Terminal number and serial communication output port mapping table: the serial communication output port is a serial communication interface address for outputting data from the interface conversion terminal to the serial port terminal, and the terminal number is the serial communication interface network terminal number of the conversion terminal.

In the serial communication interface network, if a direct communication link exists between two serial terminals, the transmission, the reception and the processing of the IP data packet are directly performed between the two serial terminals based on the definition of the IP address of the serial terminal.

The foregoing describes specific embodiments of the present invention. It is to be understood that the invention is not limited to the particular embodiments described above, and that various changes or modifications may be made by those skilled in the art within the scope of the appended claims without affecting the spirit of the invention. The embodiments of the present application and features in the embodiments may be combined with each other arbitrarily without conflict.

Claims (10)

1. A method for accessing a dual-redundancy TTE network by a serial communication interface network layer comprises a hybrid network consisting of the dual-redundancy TTE network and the serial communication interface network, and is characterized in that the dual-redundancy TTE network comprises an end system; the serial communication interface network comprises an interface conversion terminal and a serial port terminal connected with the interface conversion terminal; the hybrid network realizes communication between a TTE end system and serial port terminals and between different serial port terminals based on IP data packets, and comprises the following steps:

step S1: the interface conversion terminal is used as an end system to be accessed into a dual redundancy TTE network;

step S2: the serial communication interface loads and transmits an IP data packet according to the IP address of the network layer;

step S3: the interface conversion terminal receives and processes the IP data packet through the serial communication interface.

2. The method for accessing a dual redundancy type TTE network at a serial communication interface network layer of claim 1, wherein said IP address comprises a subnet number field and a terminal number field;

The subnet number field defines a subnet number for the TTE network, and defines a subnet number for each interface conversion terminal and a serial port terminal connected with the interface conversion terminal; the subnet numbers are unique in the same network, and the subnet numbers are reused among different networks;

defining a bit in the terminal number field as a main and standby identification bit, defining a terminal number for each end system of the TTE network, and distinguishing the two end systems of the main and standby redundancy through the main and standby identification bit; defining a terminal number for each serial port terminal of the serial communication interface network, and distinguishing the two serial port terminals with main and standby redundancy through main and standby identification bits; the interface conversion terminal is provided with a terminal number of the TTE network and a terminal number of the serial communication interface network at the same time; the terminal numbers are unique in the same sub-network, and the terminal numbers are reused in different sub-networks.

3. The method for accessing a dual redundancy TTE network at a serial communication interface network layer according to claim 2, wherein if a data transmission source terminal and a data reception destination terminal are in the same subnet, a subnet number of a source IP address and a destination IP address field in an IP packet header is assigned a fixed characteristic value; otherwise, the subnet number of the source IP address field in the IP data packet header is the subnet number of the transmitting end, and the subnet number of the destination IP address field is the subnet number of the receiving end.

4. The method for accessing a dual redundancy TTE network at a serial communication interface network layer according to claim 2, wherein said step S2 comprises the sub-steps of:

step S2.1: the source IP address field terminal number in the IP data packet header is the terminal number of the transmitting end serial port terminal, and the destination IP address field terminal number is the terminal number of the receiving end serial port terminal, the terminal number of the end system or the terminal number of the interface conversion terminal;

step S2.2: if the IP data packet is required to be forwarded to a receiving end through a TTE network, distinguishing best effort traffic and key traffic through a packet head stream category field of the IP data packet; if the key flow is adopted, the VLID is transmitted to the interface conversion terminal through the flow label field; if the best effort traffic is adopted, the flow label field is assigned to a fixed characteristic value;

step S2.3: when the end system sends an IP data packet, the terminal number of a source IP address field in the packet header is the terminal number of the sending end system; the terminal number of the destination IP address field is the terminal number of the receiving end serial port terminal, the terminal number of the end system or the terminal number of the interface conversion terminal;

step S2.4: after the serial port terminal or the terminal system bears the IP data packet, judging the subnet number and the terminal number of the destination IP address field in the packet head of the IP data packet; if the subnet number is a local subnet number or a fixed characteristic value, and the terminal number is a local terminal number, further analyzing the IP data packet; otherwise, discarding the IP data packet and reporting the error.

5. The method for accessing a dual redundancy TTE network at a serial communication interface network layer according to claim 2, wherein said step S3 comprises the sub-steps of:

step S3.1: if the subnet number field of the target IP address is the subnet number or the fixed characteristic value of the serial communication interface network where the interface conversion terminal is located, further judging the number field of the target terminal; if the number of the target terminal is the number of the local terminal, the interface conversion terminal receives and analyzes the IP data packet; if the number of the target terminal is not the local terminal number, outputting the IP data packet through the corresponding port according to the terminal number and the serial communication output port mapping table;

step S3.2: if the destination IP address subnet number field is a subnet number of the TTE network, further determining a flow class field and a destination terminal number field: if the flow class is best effort flow, the TTE network terminal number and the MAC address mapping table are searched according to the destination terminal number field to determine the MAC address of the receiving end system, the IP data packet is packaged into an MAC frame, the source MAC address is the MAC address of the transmitting interface conversion terminal, and the destination MAC address is the MAC address of the receiving end system of the TTE network; if the flow type is key flow, taking the flow label field as data to transmit VL ID, encapsulating the IP data packet into an MAC frame, converting the terminal MAC address by taking the source MAC address as a transmitting interface, and taking the virtual link of the destination MAC address as VL ID;

Step S3.3: if the number of the target IP address subnet cannot be correctly addressed, discarding the IP data packet and reporting errors;

step S3.4: the interface conversion terminal receives the MAC frame through the TTE network, analyzes the MAC frame to obtain an IP data packet, and further judges a target terminal number field if the target IP address subnet number field is a subnet number or a fixed characteristic value of the TTE network where the interface conversion terminal is located; if the terminal number is the local terminal number, the interface conversion terminal receives and analyzes the IP data packet; if the terminal number is not the local terminal number, outputting the IP data packet through the corresponding port according to the terminal number and the serial communication output port mapping table.

6. The method for accessing a dual redundancy TTE network at a serial communication interface network layer according to claim 1, wherein the interface conversion terminal establishes a mapping table of serial communication interface network subnet numbers and TTE network terminal numbers, a mapping table of TTE network terminal numbers and MAC addresses, and a mapping table of terminal numbers and serial communication output ports;

the mapping table of serial communication interface network subnet numbers and TTE network terminal numbers comprises: the TTE network terminal number is the TTE network terminal number of the interface conversion terminal, and the serial communication interface network subnet number is the subnet number defined by the interface conversion terminal and the serial port terminal connected with the interface conversion terminal;

The TTE network terminal number and MAC address mapping table comprises: the MAC address is the MAC address of the TTE network end system and the interface conversion module, and the TTE network terminal number is the terminal number of the TTE network end system and the interface conversion module;

the terminal number and serial communication output port mapping table includes: the serial communication output port is a serial communication interface address for outputting data from the interface conversion terminal to the serial port terminal, and the terminal number is the serial communication interface network terminal number of the conversion terminal.

7. The method for accessing a dual-redundancy TTE network of claim 1 wherein in said serial communication interface network, if there is a direct communication link between two serial terminals, IP packets are directly transmitted, received, and processed between the two serial terminals based on serial terminal IP address definitions.

8. The method for accessing a dual redundancy TTE network according to claim 1, wherein a serial communication interface between an interface conversion terminal and a serial port terminal supports a connection mode of one-to-two reception, two-to-one reception, one-to-one reception, and two-to-two reception, and supports asynchronous serial transmission and synchronous serial transmission.

9. The method for accessing a dual redundancy TTE network at a serial communication interface network layer of claim 1, wherein said dual redundancy TTE network further comprises a switch; and the TTE switching network is formed by a plurality of switches, and the main and standby redundant end systems are respectively and directly connected with a group of main and standby redundant switches in the switching network through Ethernet links.

10. A system for accessing a dual-redundancy TTE network by a serial communication interface network layer comprises a hybrid network composed of the dual-redundancy TTE network and the serial communication interface network, and is characterized in that the dual-redundancy TTE network comprises an end system; the serial communication interface network comprises an interface conversion terminal and a serial port terminal connected with the interface conversion terminal; the hybrid network realizes communication between a TTE end system and serial port terminals and between different serial port terminals based on IP data packets, and comprises the following modules:

module M1: the interface conversion terminal is used as an end system to be accessed into a dual redundancy TTE network;

module M2: the serial communication interface loads and transmits an IP data packet according to the IP address of the network layer;

module M3: the interface conversion terminal receives and processes the IP data packet through the serial communication interface.