Communication relay device, communication network system, communication relay method, and computer program

Abstract

To provide a communication relay device that makes it possible to apply a VLAN function even in a combination of a VLAN-incompatible master and a VLAN-compatible slave.SOLUTION: A relay device 5 relays communication between GMs 1 and 2, which are compliant with a communication protocol that is not compatible with a VLAN function, and slaves 3 and 4, which are compliant with a communication protocol that is compatible with the VLAN function, via a communication network 6. At that time, a frame conversion unit 7 converts a time-synchronized communication frame transmitted from the GM 1 or 2 into a communication frame that is compatible with the VLAN function.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a device for relaying communication performed between a plurality of masters and a plurality of slaves via a communication network, a communication network system including the device, a communication relaying method, and a computer program.

Background Art

[0002] In a network system for in-vehicle communication, for example, as disclosed in Patent Document 1, a technique called VLAN (Virtual Local Area Network) in which one physical switch is divided and used as a plurality of virtual switches may be applied.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When a plurality of in-vehicle devices communicate via a network divided into masters and slaves, there are often cases where the communication standards adhered to by each device are not unified. Therefore, there may be a combination in which the slave side supports VLAN but the master side does not support VLAN. In that case, communication using the VLAN function cannot be performed.

[0005] The present invention has been made in view of the above circumstances, and an object thereof is to provide a communication relaying device that enables the application of the VLAN function even in a combination of a VLAN-incompatible master and a VLAN-compatible slave, a communication network system including the device, a communication relaying method, and a computer program.

Means for Solving the Problems

[0006] The communication relay device (5) according to claim 1 relays communication performed between a plurality of masters (1, 2) compliant with a communication protocol that does not support the VLAN (Virtual Local Area Network) function and a plurality of slaves (3, 4, …, X) compliant with a communication protocol that supports the VLAN function via a communication network (6). At this time, the frame conversion unit (7) converts the time synchronization communication frame transmitted from the master into a communication frame that can support the VLAN function. Thereby, even if the master side does not support the VLAN function, communication with the slave with the VLAN function enabled becomes possible.

[0007] According to the communication relay device of claim 2, the master complies with IEEE802.1AS-2020, the slave complies with IEEE802.1AS-2011, and the frame conversion unit assigns the value of the domainNumber field in the message header of the time synchronization communication frame to the VLAN ID field. Thereby, the domainNumber value of the master can be used as the VLAN ID, and communication with the VLAN function enabled becomes possible.

[0008] According to the communication relay device of claim 3, when the assignment to the VLAN ID is completed, the frame conversion unit initializes the value of the domainNumber field and changes the time synchronization communication frame to a version corresponding to IEEE802.1AS-2011 for conversion. Thereby, communication between the master and the slave, which comply with different communication protocols, becomes possible.

Brief Description of the Drawings

[0009]

Figure 1

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Figure 9

Mode for Carrying Out the Invention

[0010] (First Embodiment) As shown in FIG. 1, in the in-vehicle communication system of this embodiment, for example, two masters GM1 and 2 and, for example, two slaves 3 and 4 are connected via a communication network 6 including a relay device 5. GM1 and 2 and slaves 3 and 4 that employ Ethernet (registered trademark) in the communication network are all electronic control units mounted on the vehicle; ECUs (Electronic Control Unit). GM1 and 2 comply with the communication protocol IEEE802.1AS-2020. Also, GM1 and 2 do not comply with IEEE802.1q, that is, they do not support the VLAN (Virtual Local Area Network) function. Therefore, GM1 and 2 are multi-domains that can use multiple gPTP (Generalized Precision Time Protocol) domains.

[0011] Slaves 3 and 4 comply with the communication protocol AUTOSAR (AUTomotive Open System ARchitecture), that is, IEEE802.1AS-2011. Also, Slaves 3 and 4 comply with IEEE802.1q, that is, they support the VLAN function. AUTOSAR is the specification name of a platform for realizing the commonization of in-vehicle software. And Slaves 3 and 4 are single domains that can use only one gPTP domain.

[0012] The data transmitted from GM1 and 2 is transferred to Slaves 3 and 4 via the communication line and the relay device 5. The relay devices 5 each include a control unit (not shown) and a memory, and the control unit includes a frame conversion unit 7. The frame conversion unit 7 adds information for enabling the VLAN function to the time synchronization communication frame included in the above data. The time synchronization communication frame added with the information for enabling the VLAN function is transferred to Slaves 3 and 4. That is, the relay device 5 converts the multi-domain time synchronization network of IEEE802.1AS-2020 into a single-domain time synchronization network using VLAN. Or, it can be said that the communication frame of IEEE 802.1AS-2020 without the VLAN function is converted into the communication frame of IEEE802.1AS-2011 with the VLAN function while maintaining the functionality of time domain division. The above constitutes the in-vehicle communication system 14 which is a communication network system. Hereinafter, the time synchronization communication frame may be simply referred to as a communication frame.

[0013] Figure 2 shows the communication protocols that GM1 and 2, slaves 3 and 4, and relay device 5 comply with respectively. GM1 and 2 comply with IEEE802.1AS-2020 and do not comply with AUTOSAR, IEEE802.1AS-2011, and IEEE802.1q. Slaves 3 and 4 comply with AUTOSAR, IEEE802.1AS-2011, and IEEE802.1q and do not comply with IEEE802.1AS-2020. Relay device 5 complies with AUTOSAR, IEEE802.1AS-2020, IEEE802.1AS-2011, and IEEE802.1q.

[0014] And Figure 3 shows a system configuration closer to an actual use case. GM1 is a clock source with functions corresponding to, for example, GNSS (Global Navigation Satellite System). GM2 is a clock source, for example, as an internal timer of an ECU. Slave 3 is connected to relay device 5 via bridge 8 corresponding to the VLAN function and includes end-to-end station 9, which is a communication node, and clock target 10 that operates with the clock supplied by GM1 or 2. Similarly, slave 4 includes bridge 11 corresponding to the VLAN function, end station 12, and clock target 13. Slave 4 is, for example, an ECU responsible for in-vehicle functions such as engine control and body control. Note that relay device 5 is also configured as a bridge corresponding to the VLAN function. End stations 9 and 12 are included one or more in each of slaves 3 and 4.

[0015] Slave 3 is an ECU related to, for example, ADAS (Advanced Driver-Assistance Systems) functions, complies with AUTOSAR AP (Adaptive Platform), and has a VLAN ID of 102. Slave 4 complies with AUTOSAR CP (Classic Platform) and has a VLAN ID of 101. By enabling the VLAN function, the physically connected network can be used as a virtually segmented network. Although Slave 3 and Slave 4 are connected via relay device 5, they are set so that they cannot communicate with each other. By virtually segmenting the network, it is operated so that the impact of functional failures that may occur in one network is not propagated to another network.

[0016] Next, the operation of this embodiment will be described. The process shown in FIG. 4 is realized by a microcomputer constituting the control unit of relay device 5 executing a program. The frame conversion unit 7 of relay device 5 determines whether the gPTP version of the received communication frame is 2.1, that is, whether it complies with IEEE802.1AS-2020 (S1). If the gPTP version is 2.1 (Yes), it is determined by the communication protocol that each complies with whether the communication network 6 that transmits the communication frame can use the VLAN function, that is, whether Slave 3 and 4 support the VLAN function (S2).

[0017] If it is determined as "Yes" in step S2, the value of the domainNumber field of the gPTP frame is assigned to the VLAN ID (IEEE802.1q) field in the MAC header frame (S3). Then, the domainNumber value of the received IEEE802.1AS-2020 frame is cleared to 0, and the gPTP version is changed to 2.0, etc., to convert it into an IEEE802.1AS-2011 frame, that is, to downgrade it (S4). Then, the converted frame is transmitted to the slave 3 or 4 side (S5). After executing step S5, it is determined whether there is still a received communication frame (S6). If there is still a received communication frame (Yes), the process returns to step S1 and the process is repeated. If there is no longer a received communication frame (No), the process ends.

[0018] Regarding the message header shown in FIG. 5, in 10.6.2.1 General header specifications of the standard document IEEE Std 802.1AS (registered trademark)-2020, it is shown as Table 10-7-PTP message header. In the case of the Ethernet II frame shown in FIG. 6, since the second to fourth bytes in the 4-byte IEEE802.1q field are the VLAN ID field, the domainNumber value of the above message header is assigned there. Note that the Ethernet II frame is described simply, and it includes an 8-byte preamble at the beginning and a 4-byte FCS (Frame Check Sequence) at the end.

[0019] In the case of the IEEE802.3 LLC (Logical Link Control) / SNAP (Sub Network Access Protocol) frame shown in Fig. 7, the domainNumber value is assigned to 8 consecutive bits out of the 12-bit VLAN ID format. In the same figure, the process of clearing the domainNumber value to 0 in step S4 is also shown. Note that in the same figure, the in-vehicle communication system 14 is shown in a simplified manner, and slave 3 corresponds to "SL_ECU1". Here, it is assumed that there are three or more slaves, and the Xth slave is designated as "SL_ECUX". Note that the IEEE802.3 LLC / SNAP frame is described simply, including an 8-byte preamble and SFD (Start Frame Delimiter) at the beginning and a 4-byte FCS at the end.

[0020] As described above, according to this embodiment, the relay device 5 relays the communication performed between GM1 and 2 compliant with a communication protocol that does not support the VLAN function and slaves 3 and 4 compliant with a communication protocol that supports the VLAN function via the communication network 6. At this time, the frame conversion unit 7 converts the time synchronization communication frame transmitted from GM1 or 2 into a communication frame that can support the VLAN function. Thereby, even if the master side does not support the VLAN function, communication with the VLAN function enabled becomes possible between the slaves.

[0021] More specifically, GM1 and 2 comply with IEEE802.1AS-2020, and slaves 3 and 4 comply with IEEE802.1AS-2011. In this case, the frame conversion unit 7 assigns the value in the domainNumber area in the message header of the time synchronization communication frame to the VLAN ID area. Thereby, the domainNumber value of the master can be used as the VLAN ID, and communication with the VLAN function enabled becomes possible.

[0022] Furthermore, when the assignment to the VLAN ID is completed, the frame conversion unit 7 initializes the value in the domainNumber area and performs conversion by changing the time synchronization communication frame to a version compliant with IEEE802.1AS-2011. This enables communication between GM1 and 2 and slaves 3 and 4, which comply with different communication protocols respectively.

[0023] (Second and Third Embodiments) Hereinafter, the same parts as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted, and different parts will be described. The second and third embodiments show variations in the configuration of the in-vehicle communication system. When the in-vehicle communication system 14 of the first embodiment is shown as in FIG. 7, the in-vehicle communication system 14A of the second embodiment shown in FIG. 8 has a configuration in which GM1 and 2 are arranged inside the relay device 5. Further, the in-vehicle communication system 14B of the third embodiment shown in FIG. 9 has a configuration in which only GM1 is arranged inside the relay device 5.

[0024] (Other Embodiments) The master does not necessarily need to comply with the communication protocol IEEE802.1AS-2020, and the slave does not necessarily need to comply with the communication protocol IEEE802.1AS-2011. At least, it is sufficient that the master complies with a communication protocol that is not compatible with the VLAN function, and the slave complies with a communication protocol that is compatible with the VLAN function.

[0025] The number of masters may be three or more. The master and the slave do not necessarily need to be electronic control devices. It may be applied to a network system other than the in-vehicle communication system. Although the present disclosure has been described based on the embodiments, it is understood that the present disclosure is not limited to the embodiments and structures. The present disclosure includes various modifications and modifications within the equivalent scope. In addition, various combinations and forms, and further other combinations and forms including only one element, more than one element, or less than one element thereof are also within the scope and spirit of the present disclosure.

[0026] The means and / or functions provided by each device or the like can be provided by software recorded in a physical memory device and a computer that executes the software, software only, hardware only, or a combination thereof. For example, when the control device is provided by an electronic circuit that is hardware, it can be provided by a digital circuit including a number of logic circuits or an analog circuit.

[0027] The control unit and its method described in the present disclosure may be implemented by a dedicated computer provided by configuring a processor and a memory programmed to execute one or more functions embodied by a computer program. Alternatively, the control unit and its method described in the present disclosure may be implemented by a dedicated computer provided by configuring a processor with one or more dedicated hardware logic circuits. Or, the control unit and its method described in the present disclosure may be implemented by one or more dedicated computers configured by a combination of a processor and a memory programmed to execute one or more functions and a processor configured by one or more hardware logic circuits. Further, the computer program may be stored in a computer-readable non-transitory tangible recording medium as instructions to be executed by a computer.

Description of Reference Numerals

[0028] In the drawings, 1 and 2 are GMs, 3 and 4 are slaves, 5 is a relay device, 6 is a communication network, 7 is a frame conversion unit, and 14 is an in-vehicle communication system.

Claims

1. A communication relay device that relays communication between a plurality of masters (1, 2) compliant with a communication protocol that does not support the VLAN (Virtual Local Area Network) function and a plurality of slaves (3, 4, …, X) compliant with a communication protocol that supports the VLAN function via a communication network (6), comprising a frame conversion unit (7) that converts a time synchronization communication frame transmitted from the master into a communication frame that can support the VLAN function.

2. The master complies with IEEE802.1AS (registered trademark)-2020, the slave complies with IEEE802.1AS-2011, and the frame conversion unit assigns the value of the domainNumber field in the message header of the time synchronization communication frame to the VLAN ID field. The communication relay device according to Claim 1.

3. When the assignment to the VLAN ID field is completed, the frame conversion unit initializes the value of the domainNumber field and converts the time synchronization communication frame into a version corresponding to IEEE802.1AS-2011 for conversion. The communication relay device according to Claim 2.

4. A communication network system comprising the communication relay device according to any one of Claims 1 to 3, the plurality of masters, and the plurality of slaves.

5. A method for relaying communication between a plurality of masters compliant with a communication protocol that does not support the VLAN (Virtual Local Area Network) function and a plurality of slaves compliant with a communication protocol that supports the VLAN function via a communication network, the method comprising converting a time synchronization communication frame transmitted from the master into a communication frame that can support the VLAN function.

6. When the master complies with IEEE802.1AS (registered trademark)-2020 and the slave complies with IEEE802.1AS-2011, the method assigns the value of the domainNumber field in the message header of the time synchronization communication frame to the VLAN ID field. The communication relay method according to Claim 5.

7. The communication relaying method according to claim 6, wherein when the assignment to the VLAN ID area is completed, the value of the domainNumber area is initialized, and the time synchronization communication frame is changed to a version corresponding to IEEE802.1AS-2011 and converted.

8. A program executed by a computer that configures a device for relaying communication performed between a plurality of masters compliant with a communication protocol that does not support the VLAN (Virtual Local Area Network) function and a plurality of slaves compliant with a communication protocol that supports the VLAN function via a communication network, A computer program that converts a time synchronization communication frame transmitted from the master into a communication frame capable of supporting the VLAN function and transmits it to the destination slave.

9. When the master complies with IEEE802.1AS (registered trademark)-2020, When the slave complies with IEEE802.1AS-2011, The computer program according to claim 8, wherein the value of the domainNumber area in the message header of the time synchronization communication frame is assigned to the VLAN ID area.

10. The computer program according to claim 9, wherein when the assignment to the VLAN ID area is completed, the value of the domainNumber area is initialized, and the time synchronization communication frame is changed to a version corresponding to IEEE802.1AS-2011 and converted.

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