VEHICLE COMMUNICATION GATEWAY

Abstract

Vehicle communication gateway (30) for forwarding data communication between several electronic control units (10, 20) via a first network (15) and a second network (25), wherein the vehicle communication gateway (30) comprises: a storage unit (33) designed to store one or more first messages on the first network (15) in a second message on the second network (25);a transmission unit (46) designed to transmit the second message when at least one of conditions (A) to (C) is satisfied, wherein condition (A) is such that a data size of the second message has reached a predetermined size threshold, condition (B) is such that a time elapsed since the start of storing the one or more first messages in the second message has reached a timer threshold set in the second message, and condition (C) is such that a first message from the one or more first messages, which has a trigger ID, is stored in a second message; a vehicle mode detection unit (51) designed to detect whether a state of a vehicle on which the vehicle communication gateway (30) is mounted is a vehicle stop mode, a driving mode, or a diagnostic mode while the vehicle is stopped;and a setting unit designed to dynamically adjust the predetermined size threshold and / or the timer threshold during a communication operation according to the state of the vehicle detected by the vehicle mode detection unit (51).

Description

The present invention relates to a vehicle communication gateway that mediates a message between different networks. US Patent 2017-0072876A describes a gateway of an in-vehicle network that mediates or forwards a message between different networks. When a CAN message is converted to an Ethernet message and forwarded, the gateway of the in-vehicle network stores the payload of the consecutively received CAN messages in an Ethernet packet until a predefined condition is met. CAN and Ethernet are registered trademarks. Then, when the predefined condition is met, the gateway of the in-vehicle network transmits the Ethernet packet, containing the payload of the received CAN message, to the Ethernet network. The gateway of the vehicle's own network, as described above, executes the forwarding process based on the predefined condition, so there is a problem that a flexible forwarding process cannot be executed according to the dynamic condition such as the vehicle's state. US Patent 2013 / 166778A1 discloses a vehicle communication gateway for forwarding data communication between multiple electronic control units via a first network and a second network, wherein the vehicle communication gateway comprises: a storage unit designed to store one or more first messages on the first network in a second message on the second network; and a setting unit designed to dynamically set a forwarding procedure for forwarding the second message to the second network during a communication operation according to at least one of the following: information other than information being handled in a communication and the first message stored in the second message. US Patent 2016 / 301714A1 discloses a method for operating a security gateway between the data buses of a vehicle, in which a correlation between an identification information element of a message and a processing rule is provided by a routing matrix for each message arriving on a data bus, wherein at least one processing rule associated with an identification information element has a reference information element to a security rule stored in a memory unit, which is used to filter the message with this identification information element by an interpreter. The object of the invention is to create a vehicle communication gateway that can implement a flexible forwarding process according to a dynamic condition. This object is achieved by a vehicle communication gateway with the features of claim 1. The dependent claims are directed to advantageous further developments of the invention. According to the invention, a predetermined size threshold and / or a timer threshold for the transmission of the second message during communication operation is dynamically set according to the vehicle's state. Therefore, it is possible to implement a flexible forwarding process that adapts to dynamic conditions. The above and further tasks, features, and advantages of the present invention will become clear with reference to the following detailed description and the accompanying drawings. These show: Fig. 1 a diagram showing a configuration of a vehicle network system; Fig. 2 a diagram showing messages in a first and a second network; Fig. 3 a diagram showing a configuration of a gateway of the present embodiment; Fig. 4 a diagram showing a configuration of a comparator gateway; Fig. 5 a diagram illustrating packet forwarding in the case of one-to-one conversion; Fig. 6 a diagram illustrating packet forwarding when a buffer-full condition or a timeout condition is a transmission condition; Fig. 7 a diagram showing a mode for transmitting a message when a fixed timer expires; Fig.Figure 8 shows a diagram illustrating a mode for transmitting a message when the buffer is full; Figure 9 shows a diagram illustrating packet forwarding when a transmission condition is a timeout condition in a buffer-full case or a case of a variable timer; Figure 10 shows a diagram illustrating a mode for transmitting a message when a variable timer expires; Figure 11 shows a diagram illustrating packet forwarding in the case where a transmission condition is a timeout condition in a buffer-full case or a case of a variable timer, or a receive condition of a trigger frame; Figure 12 shows a diagram illustrating a mode for transmitting a message when a trigger frame is received; Figure 13 shows a diagram illustrating a message in which a size threshold and a timer threshold are dynamically changed according to the present embodiment; FigureFig. 14 a diagram showing a switching or alternating operation of the forwarding system according to the vehicle mode of the present embodiment; Fig. 15 a diagram showing a message in which a size threshold and a timer threshold are fixed, for comparison; Fig. 16 a diagram showing a forwarding system that is fixed or fixed, independent of a vehicle mode, for comparison; Fig. 17 a diagram showing a setting example of a table used in the variable forwarding system and a setting example of a schedule table for a signal ID; Fig. 18 a diagram showing a switching or alternating operation of a forwarding system according to a communication load according to the present embodiment; Fig. 19 a diagram showing a communication load and a first and a second load threshold; Fig. 20 a diagram showing an on / off setting of a table switching operation orFigure 21 shows a table switching operation according to a signal value; Figure 21 shows a diagram showing a way of switching tables according to signal values; Figure 22 shows a sequence diagram or flowchart showing a forwarding process according to the embodiment; Figure 23 shows a sequence diagram or flowchart showing a forwarding system switching determination and an execution process according to the present embodiment; Figure 24 shows a sequence diagram or flowchart showing an Ethernet transmission process according to the present embodiment; and Figure 25 shows a sequence diagram or flowchart showing a comparison forwarding process. 1. Structure 1-1. Network system First, the configuration of the vehicle-mounted network system 100 according to the present embodiment is described with reference to Fig. 1. The vehicle's own network system 100 includes a first network 15, a second network 25 and a vehicle communication gateway (hereinafter: gateway) 30. The first network 15 is a network according to a first communication protocol and is connected to one or more first electronic control units (hereinafter: first ECUs) 10. The ECU 10 transmits (sends) and receives a first message according to the first communication protocol. The second network 25 is a network according to a second communication protocol and is connected to one or more second electronic control units (hereinafter: second ECUs) 20. The second ECU 20 transmits (sends) and receives a second message, which contains longer payload data than the first message, according to the second communication protocol. The first network 15 is, for example, a network according to the CAN protocol or the CAN FD protocol, and the first message is a CAN message or a CAN FD message. In this embodiment, the first network 15 is a CAN network, and the first message is a CAN message. Furthermore, in the present embodiment, the second network 25 is a network according to the Ethernet protocol, and the second message is an Ethernet message. The gateway 30 contains a first network transmission / receiving unit 31, a second network transmission / receiving unit 32 and a communication forwarding unit 33 and performs a forwarding operation of a data communication between the first ECU 10 and the second ECU 20 via the first network 15 and the second network 25. The first network transmission / receiving unit 31 receives the first message from the first ECU 10 via the first network 15 and transmits the first message to the first ECU 10 via the first network 15. In this embodiment, the first network transmission / receiving unit 31 is a CAN communication controller. The second network transmission / receiving unit 32 receives the second message from the second ECU 20 via the second network 25 and transmits the second message to the second ECU 20 via the second network 25. In this embodiment, the second network transmission / receiving unit 32 is an Ethernet communication controller. The communication forwarding unit 33 converts a first message received via the first network 15 into a second message and transmits the second message to the second network 25. Furthermore, the communication forwarding unit 33 converts a second message received via the second network 25 into a first message and transmits the first message to the first network 15. In particular, when the communication relay unit 33 transmits one or more first messages received over the first network 15 to the second network 25, the communication relay unit 33 stores one or more first messages in a single second message, as shown in Fig. 2. That is, the communication relay unit 33 combines (i.e., packs) one or more first messages to produce a single second message. When the communication forwarding unit 33 transmits the second message received via the second network 25 to the first network 15, it splits (i.e. unpacks) the second message into one or more first messages. 1-2. Gateway The following describes a specific configuration of the Gateway 30 with reference to Fig. 3. The Gateway 30 contains basic software (hereinafter: BSW) 400 as an AUTOSAR standard module and a user application 450. AUTOSAR is a registered trademark. The BSW 400 contains CanDrv 41, CanIf 42, PduR 43, COM 44, RTE 45, SoAd 47, TcpIp 48, EthIf 49 and EthDrv 50. CanDrv 41 is a driver for transmitting and receiving a CAN message. CanIf 42 is an interface for using a CAN message. When a message is sent from the first network 15 to the second network 25, the CanDrv removes the ID (for example, 100) and the header from the CAN message and adds an ID that is irrelevant to the protocol (for example, 200) to create a protocol data unit (hereinafter referred to as PDU). The PduR 43 is a module that performs PDU routing. In this embodiment, the PduR 43 forwards the PDU to the SoAd 47 for storage and also forwards the PDU to the SW-C 46 for notification. The COM 44 is a module that handles signals contained in the PDUs. The RTE 45 is a module that connects the BSW 400 and the user application 450, and is an execution environment provided for the user application 450 to use the AUTOSAR platform. The SoAd 47 is a module that manages sockets. When the SoAd 47 sends a message from the first network 15 to the second network 25, it selects a socket according to the ID of the PDU forwarded by the PduR 43. The TcpIp 48 manages a port number and an IP address. When a message is sent from the first network 15 to the second network 25, the TcpIp 48 distributes the PDU forwarded by the PduR 43 to the buffer of the socket selected by the SoAd 47. EthIf 49 is an interface for using an Ethernet message. When a message is sent from the first network 15 to the second network 25, EthIf 49 creates an Ethernet message by appending the destination and source MAC addresses to the socket mediated by TcpIp 48. EthDrv 50 is a driver for sending and receiving Ethernet messages. The user application 450 contains a forwarding control unit 46 (hereinafter: SW-C). The SW-C can be a user application. The SW-C 46 contains a vehicle mode detection unit 51, a communication load monitoring unit 52, and a forwarding table 53, and receives a message PDU as a signal. The vehicle mode detection unit 51 detects the vehicle's state from the received signals of the vehicle speed sensor and the brake sensor. Specifically, the vehicle mode detection unit 51 detects whether the vehicle is in stop mode, drive mode, or diagnostic mode while the vehicle is stopped. Stop mode is a state in which the ignition is switched on and the vehicle is not moving. Diagnostic mode is a state in which the vehicle is being diagnosed at a service station or similar facility. The communication load monitoring unit 52 monitors statistical information (e.g., communication load) of a communication in the first network 15 and the second network 25 based on the signal transmission frequency or frequency and similar information. Forwarding table 53 is a table for dynamically setting a procedure for forwarding a message from the first network 15 to the second network 25. The details of forwarding table 53 are described later. The SW-C 46 selects a size threshold and a timer threshold to be used from forwarding table 53, based on at least one piece of information other than the information being processed in the communication and a signal information, and dynamically sets a forwarding procedure during a communication operation. The information other than the information being processed in the communication is not signal information itself, but information obtained by processing the signal information; that is, information that is acquired or calculated based on the signal information, for example, vehicle status information or statistical communication information. Furthermore, the SW-C 46 calculates the data size from the received signal information. Additionally, the SW-C 46 compares the scheduled time preset for the signal with the timer threshold set in the buffer of the second message that stores the signal, and updates the timer threshold of the second message to the lower of these two values ​​(i.e., the value reached earlier). The SW-C 46 then transmits the second message to the second network 25 if at least one of the following conditions (A) to (C) is met to determine the transmission of the second message: (A) The data size of the second message has reached the predetermined size threshold. (B) The time elapsed since the start of storing the PDU corresponding to the first message in the buffer of the second message has reached the timer threshold set in the buffer of the second message. (C) A PDU corresponding to the first message, which has a trigger ID, is received. The SW-C 46 transmits the signal contained in the transmission trigger via the RTE 45 if at least one of conditions (A) to (C) is met. The transmission trigger is the PDU corresponding to the first message that has a predetermined, specific trigger ID. The BSW 400 has a mechanism for immediately transmitting the second message when the transmission trigger is stored. Therefore, the SW-C 46 can dynamically adjust the forwarding procedure depending on the situation by changing the size threshold and the timer threshold. As shown in Fig. 4, in the comparison gateway 300, the storage PDU is only forwarded from the PduR 43 to the SoAd 47, and the message PDU is not transmitted to the user application 450. Therefore, the size threshold and the timer threshold are fixed to preset values ​​and are not changed depending on the situation, and thus the forwarding procedure is fixed. 2. Forwarding procedure 2-1. Outline of the forwarding procedure The following describes a forwarding procedure in the case of forwarding a message from the first network 15 to the second network 25. One of the forwarding methods is a one-to-one conversion, as shown in Fig. 5. That is, the PDU corresponding to a first message is stored in a buffer of the second message, and the second message is transmitted. As shown in Fig. 6, another forwarding method can be used to convert and store PDUs corresponding to N first messages in a buffer of a second message. "N" is a natural number. The second message is transmitted when either of the above conditions (A) and (B) is met. That is, the second message is transmitted when the buffer's data size reaches its size threshold, or when the time elapsed since the first PDU was started reaching the buffer's timer threshold. The timer threshold is a value preset for the buffer, independent of the PDU stored in the buffer. A timer using the timer threshold is defined as a fixed timer. Fig. 7 shows a state for transmitting the second message when the elapsed time reaches the timer threshold. The elapsed time from when the PDU corresponding to the first message with ID: 100 is stored in the buffer until the PDU corresponding to the first message with ID: 102 is stored in the buffer reaches the timer threshold, and the data stored in the buffer is transmitted as the second message. Figure 8 illustrates the state of transmitting the second message when the buffer's data size reaches the size threshold. When the PDU corresponding to the first message (ID: 100) is stored in the buffer, followed by the PDU corresponding to the first message (ID: 101), the buffer's data size reaches the size threshold, and the data stored in the buffer is transmitted as the second message. The PDU corresponding to the first message (ID: 102), which follows the PDU corresponding to the first message (ID: 101), is stored in the next buffer. As shown in Fig. 9, according to yet another forwarding method, a conversion can be used to store PDUs corresponding to N first messages in a buffer of the second message. If either of the above conditions (A) and (B) is met, the second message is transmitted. That is, if the buffer's data size reaches the size threshold, or if the time elapsed since the start of storing the PDU corresponding to the first part of the first message reaches the buffer's timer threshold, the second message is transmitted. The timer threshold mentioned here is a value that is updated according to the PDU corresponding to the first message being stored in the buffer.Specifically, the buffer timer threshold is updated to a shorter time between reaching the deadline set for each PDU corresponding to the first message and reaching the buffer timer threshold. A timer using the timer threshold is defined as a variable timer. Note that the case where the buffer data size reaches the size threshold is the same as shown in Figure 8. Fig. 10 shows a state of transmitting the second message when the timer threshold is updated according to the date set in the PDU corresponding to a respective first message, and the elapsed time reaches the updated timer threshold. According to yet another forwarding method, a conversion can be used to store PDUs corresponding to N first messages in a buffer of the second message, as shown in Fig. 11. The second message is then transmitted when any of the conditions (A) to (C) described above are met. That is, when the buffer's data size reaches the size threshold, or when the time elapsed since the start of storing the PDU corresponding to the first part of the first message reaches the buffer's timer threshold, or when the transmission trigger, a PDU corresponding to the first message with the trigger ID, is stored in the buffer, the second message is transmitted. The timer threshold is a value that is updated according to the PDU corresponding to the first message stored in the buffer. Fig. 12 shows a state of transmitting the second message when the PDU corresponding to the first message, which has the trigger ID of 102, is stored in the buffer. Note that the case in which the buffer data size reaches the size threshold is the same as in Fig. 8. The case in which the time elapsed since the start of storing the PDU corresponding to the first part of the first message reaches the buffer timer threshold is the same as in Fig. 10. In the fixed comparison-pass-through method shown in Fig. 15, the timekeeper threshold of the fixed timekeeper, the initial value of the timekeeper threshold of the variable timekeeper, and the size threshold are fixed values. As shown in Fig. 16 according to the comparison example, even when the vehicle state changes to stop mode, drive mode, and diagnostic mode, the timekeeper threshold of the fixed timekeeper, the initial value of the timekeeper threshold of the variable timekeeper, and the size threshold remain constant and fixed. As shown in Fig. 13, in the variable forwarding method of the present embodiment, the timekeeper threshold of the fixed timekeeper, the initial value of the timekeeper threshold of the variable timekeeper, and the size threshold are variable. In particular, in the variable forwarding method of the present embodiment, the timekeeper threshold of the fixed timekeeper, the initial value of the timekeeper threshold of the variable timekeeper, and the size threshold are determined according to at least one of the vehicle state, the communication load, and the signal information contained in the first message.In the present embodiment, the timekeeper threshold of the fixed timekeeper, the initial value of the timekeeper threshold of the variable timekeeper, and the size threshold are set according to the vehicle condition and / or the communication load and the signal information contained in the first message. 2-2. Discontinuation of the forwarding procedure according to the vehicle condition Fig. 14 shows a state in which the timekeeper threshold of the fixed timekeeper, the initial value of the timekeeper threshold of the variable timekeeper, and the size threshold are dynamically adjusted according to the vehicle state. Messages of the same type are indicated with the same diagonal dashes. When the vehicle is in stop mode, the message transmission frequency is low, so the forwarding procedure is set to allow low-frequency messages to be forwarded with minimal delay. Because the message transmission frequency is low, there is little need to update the timer threshold according to the date set in the signal contained in the first message. Therefore, a fixed timer is used in stop mode. It is then more efficient to increase the forwarding frequency of the second message, which has a small data size, compared to sending a second message with a large data size. As shown in Fig.As shown in Figure 14, the size threshold is therefore set to small, medium or large, and the timekeeper threshold of the fixed timekeeper is set to small, medium or large. When the vehicle is in driving mode, the message transmission frequency is high, so the forwarding procedure is configured to allow high-frequency messages to be forwarded with minimal delay. Because the message frequency is high and the delay requirement is often critical, it is essential to update the timer threshold. Therefore, a variable timer is used in driving mode. Additionally, a trigger ID is set for a critical message, which acts as a transmission trigger. Since the transmission frequency is high, forwarding efficiency decreases if the data size is too small. As shown in Figure 14, the size threshold is therefore set to medium to large with some leeway, and the initial value of the variable timer's threshold is set to medium. When the vehicle is in diagnostic mode, the message transmission frequency is high, so the forwarding procedure is configured to allow high-frequency messages to be forwarded with minimal delay. In diagnostic mode, unlike in driving mode, updates and similar data are transmitted, and it is necessary to forward multiple messages together. Therefore, in diagnostic mode, the size threshold must be set higher than in driving mode. Furthermore, in diagnostic mode, there is a legal requirement that each initial message must be sent within a specified time. Therefore, the timer threshold must be updated according to the time set for each initial message. Consequently, a variable timer is used in diagnostic mode, as shown in Fig.As shown in Figure 14, the size threshold is then set to a large value, and the initial value of the timekeeper threshold of the variable timekeeper is set to a large value. Fig. 17 shows an example setting of a table used when the forwarding procedure is set according to the vehicle state, and an example setting of a time for a given signal ID. The time specifies the maximum allowed time from when the corresponding signal was stored in the buffer until the time the signal is transmitted, in a case where the variable timer is used. Table 1 is a table used, for example, in a stop mode. The packet destination ID specifies a signal ID, which is an object to be stored in a second message. The "off" state for using the updated timer indicates that the fixed timer is being used. In this case, the timer threshold is fixed at 3 ms, regardless of the time set for a particular signal ID. Here, the use of the trigger ID is set to "on," and signal ID 100 is set as the trigger ID. Therefore, if the first message with signal ID 100 is stored in the buffer, the second message will be transmitted even if the elapsed time has not reached the timer threshold and the buffer size has not reached the size threshold. Furthermore, Table 2 is a table used, for example, in a driving mode. The "On" state for using the updated timer indicates that a variable timer is being used. In this case, the initial value of the timer threshold is set to 5 ms. Then, each time a signal is stored in the buffer, the time set in the signal being stored in the buffer is compared with the timer threshold set in the buffer, and the first of these two time values ​​is stored as the new timer threshold value. Additionally, Table 3 is a table used, for example, in the diagnostic mode. 2-3. Adjusting the forwarding procedure according to the communication load Figures 18 and 19 show a situation in which the timer threshold of the fixed timer, the initial value of the timer threshold of the variable timer, and the size threshold are dynamically set according to the communication load of at least one network from the first network 15 and the second network 25. In this embodiment, the size threshold is dynamically set according to the communication load of the first network 15. Similar messages are shown with the same diagonal dashed lines. When the communication load is low or medium (out of low, medium, and high), the message transmission frequency is low. Therefore, the forwarding procedure is configured to allow low-frequency messages to be forwarded with minimal delay. Because the message frequency is low, it is not necessary to update the timer threshold according to the time set in the signal contained in the first message. Therefore, a fixed timer is used when the communication load is low or medium. It is then more efficient to increase the forwarding frequency of the second message, which has a small data size, compared to when the second message has a large data size. As shown in Fig.As shown in Figure 18, the size threshold is therefore set to small, and the timekeeper threshold of the fixed timekeeper is set to small. When the communication load is high, the frequency of message transmission is also high. Therefore, the forwarding procedure is configured to allow high-frequency messages to be forwarded with minimal delay. Since multiple messages need to be forwarded simultaneously, the size threshold must be appropriately adjusted. Furthermore, a variable timer is used to meet the delay requirement. As shown in Figure 18, the size threshold is set to a large value, and the initial threshold value of the variable timer is also set to a large value. To reduce the delay in switching routing methods due to the processing time of the communication load and to prevent frequent switching methods, a first load threshold and a second load threshold can be set as shown in Fig. 19. The first load threshold determines that the communication load is tending to increase, and the second load threshold determines that the communication load is tending to decrease. Then, when the communication load increases from a value less than the first load threshold to a value greater than the first load threshold, the first load threshold is changed to a large value, and the fixed timer is changed to a variable timer. Thus, the initial value of the timer threshold can be set to a large value.If the communication load drops from a value greater than the second load threshold to a value less than the second load threshold, the size threshold is changed to small, and the variable timer is changed to the fixed timer so that the timer threshold can be set to a small value. Note that in Fig. 19, the threshold between high and medium communication load is defined as the first load threshold, and the threshold between medium and low communication load is defined as the second load threshold. The threshold in the case where the communication load changes from medium to high can be defined as the first threshold, the threshold in the case where the communication load changes from medium to low can be defined as the second threshold, the threshold in the case where the communication load changes from high to medium can be defined as the third threshold, and the threshold in the case where the communication load changes from low to medium can be defined as a fourth threshold.The thresholds are, in descending order, the first threshold, the third threshold, the fourth threshold, and the second threshold (i.e., first threshold > third threshold > fourth threshold > second threshold). This prevents frequent changes to the forwarding procedure. 2-4. Setting the forwarding procedure according to the signal information Figures 20 and 21 show an example of the on / off state for changing the table used when a forwarding procedure is set according to the signal information, and a table-changing mode. As shown in Figure 20, when the table-changing operation based on the signal value in a given table is in the on state, the table to be used is changed according to the signal value, as shown in Figure 21. For example, if the signal value is greater than 100, Table 3 is used. If the signal value is less than 10, Table 2 is used, and if the signal value is equal to or greater than 10 and equal to or less than 100, Table 1 is used. 3. Forwarding process The following describes the procedure of the variable forwarding type forwarding process performed by the gateway 30 according to the present embodiment, with reference to the sequence diagram of Fig. 22. First, SW-C 46 performs forwarding procedure change determination and execution processing in S10. The details of this forwarding procedure change determination and execution processing are described later. In S20, the communication controller 31 receives the CAN frame. In S30, the received CAN frame is transmitted by the communication controller 31 to the CanDrv 41 as a receipt notification. In S40, the received CAN frame is transmitted by the CanDrv 41 to the CanIf 42 as a receipt notification. In S50, the PDU generated from the received CAN frame is transmitted by the CanIf 42 to the PduR 43 as a receipt notification. In S60, PduR 43 performs a forwarding process. Specifically, PduR 43 transmits a message PDU to COM 44 as a receipt notification and also transmits a storage PDU to SoAd 47 as a transfer request. In S70, the SoAd 47 stores the received PDU in the temporary buffer for packing. In S80, the SoAd 47 transmits a return value related to the transmission request to the PduR 43. In S90, the message PDU is transmitted as a receipt notification from the PduR 43 to the SW-C 46 via the COM 44 and the RTE 45. On the other hand, SW-C 46 in S100 determines whether the trigger condition regarding the timer is met. Specifically, SW-C 46 determines whether the time elapsed since the PDU started storing data in the buffer has reached the timer threshold set in the buffer. If the forwarding procedure is for a variable timer, SW-C 46 updates the buffer's timer threshold using the date set in the signal contained in the notification PDU. Furthermore, SW-C 46 determines in S110 whether the trigger condition regarding the buffer size is met. Specifically, SW-C 46 determines whether the buffer data size has reached the size threshold. SW-C 46 calculates the current buffer data size from the data size of the message PDU received, insofar as it represents the signal information to be stored in a buffer. Gateway 30 repeatedly executes the process from S20 to S110 until the PDU corresponding to the CAN frame with the trigger ID is transmitted to SoAd 47 and the trigger condition in SoAd 47 is met. The trigger condition in SoAd 47 is met when SoAd 47 receives the PDU corresponding to the CAN frame with the trigger ID. Subsequently, depending on the fulfillment of the trigger condition in S100 or S110 in S120, the CAN frame with the trigger ID is transmitted as a transmission request from the SW-C 46 to the SoAd 47 via the RTE 45, the COM 44 and the PduR 43. In S130, the SoAd 47, the TcpIp 48, the EthIf 49, the EthDrv 50, and the communication controller 31 execute the Ethernet transmission process. The details of the Ethernet transmission process are described later. Additionally, in S140, the return value for the transmission request is transmitted from the SoAd 47 to the SW-C 46 via the PduR 43, the COM 44, and the RTE 45. If, on the other hand, the CAN frame with the trigger ID is received before the trigger condition in S100 and S110 is met, the CAN frame with the trigger ID is transmitted in S150, similar to S120. Then, the Ethernet transmission process is executed in S130, and the return value for the transmission request is transmitted in S160, similar to S140. The following describes the forwarding procedure change determination and execution processing (in S10) with reference to the sequence diagram of Fig. 23. In S15, the SW-C 46 transmits a communication load procurement request to the communication load monitoring unit 52. In S25, the communication load monitoring unit 52 procures the communication load of the first network 15 and transmits the procured communication load as a communication load procurement response to the SW-C 46. In S35, the SW-C 46 transmits a vehicle mode procurement request to the vehicle mode acquisition unit 51. In S45, the vehicle mode acquisition unit 51 procures the vehicle mode and transmits the procured vehicle mode to the SW-C 46 as a vehicle mode procurement response. In S55, SW-C 46 determines whether the forwarding procedure change condition is met, based on the received communication load and the received vehicle mode. That is, it determines whether the communication load or the vehicle mode has changed. If the forwarding procedure change condition in S55 is met, SW-C 46 changes the forwarding procedure in S65. This means that at least one of the size threshold and the timer threshold of the fixed timer, or the initial value of the timer threshold of the variable timer, is changed. Conversely, if the forwarding procedure change condition in S55 is not met, the forwarding procedure change determination and execution process ends. The Ethernet transmission process (in S130) is described below with reference to the sequence diagram in Fig. 24. In S135, a buffer backup request is transmitted from the SoAd 47 to the EthDrv 50 via the TcpIp 48 and the EthIf 49. In S145, the EthDrv 50 saves a transmission buffer. Subsequently, in S155, the return value for the buffer backup request is transferred from the EthDrv 50 to the SoAd 47 via the EthIf 49 and the TcpIp 48. In S165, the EthDrv 50 copies the data from the temporary buffer of the SoAd 47 into the secured transmission buffer, sets the header information, which contains the MAC address and frame type, in the transmission buffer, and generates the second message. Subsequently, in S175, the transmission request from the transmission buffer is sent from the SoAd 47 to the communication controller 31 via the TcpIp 48, the EthIf 49, and the EthDrv 50. In S185, the communication controller 31 transmits the second message to the second network 25. In S195, the return value for the transmission request is transmitted from the communication controller 31 to the SoAd 47 via the EthDrv 50, the EthIf 49 and the TcpIp 48. In the following, for comparison with the forwarding process of the variable forwarding type according to the present embodiment, the procedure of a comparison forwarding process of the fixed forwarding type is described with reference to the sequence diagram of Fig. 25. In S200 to S230, the same process is carried out as in S20 to S50 of Fig. 22. In S240, the PduR 43 performs a forwarding process. In particular, the PduR 43 transmits a PDU for storage to the SoAd 47 as a transfer request, but in comparison to the present embodiment, the PDU is not transmitted to the COM 44 for notification. In S250, the SoAd 47 stores the received PDU in the temporary buffer for packing. In S260, the SoAd 47 transmits the return value with respect to the transmission request to the PduR 43. Then, similar to the present embodiment, the Ethernet transmission process is executed in S130. In the forwarding process according to the present embodiment, in contrast to the comparison forwarding process, not only the PDU for storage is transferred to the SoAd 47, but also the PDU for notification to the SW-C 46. Therefore, in the forwarding process according to the present embodiment, the size threshold and the timer threshold are dynamically changed during communication operation using the message PDU, while the AUTOSAR standard module is used similarly to the comparison forwarding process. 2. Effects According to the first embodiment described above, the following effects can be achieved. (1) The forwarding procedure is set during communication operation according to at least one of the vehicle information, the communication load, and the signal information of the first message stored in the second message. Therefore, it is possible to implement a flexible forwarding process according to dynamic conditions. (2) The vehicle state can be detected, and the timer threshold and the size threshold can be set according to the detected vehicle state. As a result, it is possible to implement a forwarding process suitable for the message transmission frequency or frequency according to the vehicle state. (3) The communication load is monitored, and the timer threshold and the size threshold can be set according to the communication load.As a result, it is possible to implement a forwarding process suitable for the message transmission frequency according to the communication load.(4) The size threshold and the timer threshold are set dynamically. Accordingly, the condition for determining the transmission of the second message can be changed according to at least one of the vehicle state, the communication load, and the signal information of the first message, and a flexible forwarding process can be implemented. Other embodiments Although one embodiment of the present invention has been described above, the present invention is not limited to the embodiment described above, and various modifications are possible. (A) In the embodiment described above, the first message is a CAN message and the second message is an Ethernet message. However, the present invention is not limited thereto. As long as the first message and the second message satisfy the relationship that the payload of the first message is smaller or shorter than the payload of the second message, the present invention can be used. (B) Several functions of one element in the embodiment described above can be implemented by several elements, or one function of one element can be implemented by several elements.Furthermore, multiple functions of several components can be implemented by a single component, or a single function that is implemented by several components can be implemented by a single component. A part of the configuration of the embodiment described above can be omitted within the scope of the claims. At least a part of the configuration of the embodiment described above can be added to or replaced by the configuration of another embodiment described above within the scope of the claims.(C) In addition to the vehicle-integrated communication gateway described above, a vehicle-integrated communication network system which includes the vehicle-integrated communication gateway as a component, a program for causing a computer to act as the vehicle-integrated communication gateway, a semiconductor memory in which the program is recorded, a non-volatile storage medium, a communication forwarding method, and the like may be provided in various forms. The controls and procedures described above can be implemented by a dedicated associated computer created by configuring a memory and a processor programmed to execute one or more functions defined in computer programs. Alternatively, the controls and procedures described above can be implemented by a dedicated associated computer created by configuring a processor provided by one or more dedicated associated hardware logic circuits.Alternatively, the controls and procedures described above can be implemented by one or more dedicated associated computers, created by configuring a combination of memory and a processor programmed to perform one or more specific functions, and a processor provided by one or more hardware logic circuits. The computer programs can be stored as instructions to be executed by a computer on a non-volatile, computer-readable medium. Note that in this application, a flowchart or the processing of the flowchart contains sections (also referred to as steps), each designated, for example, as S10. Furthermore, each section can be divided into several subsections, or several sections can be combined into a single section. Each of the sections thus configured can also be referred to as a device, module, or setup.

Claims

Vehicle communication gateway (30) for forwarding data communication between several electronic control units (10, 20) via a first network (15) and a second network (25), wherein the vehicle communication gateway (30) comprises: a storage unit (33) designed to store one or more first messages on the first network (15) in a second message on the second network (25);a transmission unit (46) designed to transmit the second message when at least one of conditions (A) to (C) is satisfied, wherein condition (A) is such that a data size of the second message has reached a predetermined size threshold, condition (B) is such that a time elapsed since the start of storing the one or more first messages in the second message has reached a timer threshold set in the second message, and condition (C) is such that a first message from the one or more first messages, which has a trigger ID, is stored in a second message; a vehicle mode detection unit (51) designed to detect whether a state of a vehicle on which the vehicle communication gateway (30) is mounted is a vehicle stop mode, a driving mode, or a diagnostic mode while the vehicle is stopped;and a setting unit designed to dynamically adjust the predetermined size threshold and / or the timer threshold during a communication operation according to the state of the vehicle detected by the vehicle mode detection unit (51). Vehicle communication gateway (30) according to claim 1, wherein the setting unit contains the predetermined size threshold and / or the timer threshold during communication operation according to statistical information of the communication in at least one from the first network (15) and the second network (25). Vehicle communication gateway (30) according to claim 1 or 2, wherein when the state of the vehicle detected by the vehicle mode detection unit (51) is the driving mode, the setting unit sets the predetermined size threshold higher than when the state of the vehicle is the vehicle stop mode. Vehicle communication gateway (30) according to one of claims 1 to 3, wherein if the state of the vehicle detected by the vehicle mode detection unit (51) is the diagnostic mode while the vehicle is stopped, the setting unit sets the predetermined size threshold higher than if the state of the vehicle is the vehicle stop mode. Vehicle communication gateway (30) according to one of claims 1 to 3, wherein if the state of the vehicle detected by the vehicle mode detection unit (51) is the diagnostic mode while the vehicle is stopped, the setting unit sets the timer threshold higher than if the state of the vehicle is the vehicle stop mode.

Images