JPH118647A - Gateway - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a gateway in pluralities of networks. SOLUTION: This gateway 4 that attains communication over pluralities of networks 1, 2, 4 for conducting communication of packets each consisting of frame data including control data and data is provided with a monitor section 42 that monitors communication over different networks based on sender and destination information of each packet and a data conversion section 43 that generates frame data of a destination format among pluralities of networks, sets a packet to a data area in frame data so as to attain packet communication in the network of the destination on the occurrence of communication of the packet over different networks based on the monitor result of the monitor section 42.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a gateway for performing protocol conversion between a plurality of networks, and more particularly to a gateway which can be simplified in a local area network (LAN) in a vehicle.

[0002]

2. Description of the Related Art Vehicles include a compact disc (CD) as an audio visual device (AVC) and a tuner, and an electronically controlled fuel injection (EF) as a vehicle control device.
I), devices such as anti-lock brake system (ABS), power windows (P /
W) and door locks (D / L). To connect these devices, each wiring (signal line)
Therefore, every time one device is added, it is necessary to consider a wiring (routing) method. In order to simplify the wiring work, technologies such as LAN (local area network) and BUS (bus) connection have recently been used. The audio-visual equipment LAN, the vehicle control equipment LAN, and the body equipment LAN differ in transmission speed and quality required by the equipment.
For example, in a LAN for audiovisual equipment,
The transmission speed is 20 kbps, the data reliability requirement is low, and the transmission speed is 1 Mb in the vehicle control equipment LAN.
The data transmission rate is 10 kbps and the data reliability is low in a LAN for body equipment.

[0003] A gateway is required to perform communication between LANs of these different protocols. FIG. 4 is a diagram illustrating a conventional gateway. In this figure, the OSI
(Open System Interconnection) environment and TCP (Transm
ission Control Protocol) / IP (Internet Protocol)
An example of an OSI TCP / IP gateway interconnecting environments is shown. The OSI / TCP / IP gateway converts a protocol between the OSI network and the TCP / IP network to enable communication across the network.

[0004]

However, the gateway recognizes all data (contents of data (control data, data), a source address, a destination address, etc.) and replaces all data with a different protocol. Therefore, there is a problem that the processing time is long and the cost is high.

[0005] Therefore, an object of the present invention is to provide a gateway which can perform processing in a short time and is inexpensive in view of the above problems.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention enables communication over a plurality of networks for performing packet communication by dividing control data and frame data including data. In the gateway, when there is a monitoring unit that monitors communication performed across different networks based on the source and destination information of the packet, and there is communication of a packet that crosses different networks based on the monitoring result of the monitoring unit. A data conversion unit for generating frame data in a format of a destination of the plurality of networks, placing the packet in an area of data in the frame data, and enabling packet communication to be performed on the destination network; And

By transmitting frame data to be transmitted as a part of frame data of a different network by this means, protocol conversion processing is simplified, processing time is shortened, and cost is reduced. The data conversion unit may put only the data area in the frame data included in the packet on the data area in the frame data of the transmission destination. Further, the protocol conversion process is simplified.

In addition, the apparatus further comprises a memory for storing data of a packet communicated through a plurality of networks, wherein the memory backs up a process of placing the packet in a data area in frame data of a source format by the data conversion unit. When there is communication of a packet over different networks based on the monitoring result of the monitoring unit, data of the packet communicated over a plurality of networks is stored. By this means, the capacity of the memory to be backed up can be reduced.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram illustrating an example of a gateway according to the present invention. This figure shows multiple LANs
For example, audiovisual equipment (AV
C) system LAN1, vehicle control device system LAN2, and body device system LAN3. Audio / visual equipment LAN1
Are connected, and LA of the vehicle control equipment system is connected.
Are connected to N2, and the body equipment system 3 is connected to the body equipment LAN3.
1, 32,... Are connected. The gateway 4 converts a protocol for performing communication across the audio-visual equipment LAN 1, the vehicle control equipment LAN 2, and the body equipment LAN 3.

FIG. 2 shows the L of the audio / visual equipment system.
It is a figure explaining data communicated with AN1, LAN2 of a vehicle control apparatus system, and LAN3 of a body apparatus system, respectively. As shown in the figure, the format of one frame data communicated on the audio / visual device LAN 1 is control data, data, for example, SOF, data and device identification number, additional information, data of maximum length 512 bits, CRC. , EOF. One frame data is communicated in a plurality of packets, and the length of one packet is about 10
00 bits. Similarly, LAN2 of the vehicle control equipment system
The format of one frame data communicated by the control data is control data, data, for example, SOF, additional information, data and device identification number, data of a maximum length of 64 bits, CRC,
RES, EOF. One frame data is communicated in a plurality of packets, and the length of one packet is about 100 bits. Furthermore, LA of body equipment LAN3
The format of one frame data communicated by N3 is control data, data, for example, SOF, additional information, data and device identification number, 8- to 88-bit data, CR
C, EOM, RES, and EOF. One frame data is communicated in a plurality of packets, and the length of one packet is about 100 bits.

Returning to FIG. 1, the processing circuit 4 of the gateway 4
1 includes a monitoring unit 42, a data conversion unit 43, and a memory 44. The monitoring unit 42 determines whether the transmission source and destination of the packets transmitted at different transmission speeds and in different formats in each of the audio-visual device LAN 1, the vehicle control device LAN 2, and the body device LAN 3 are LAN. Monitor if they straddle each other. The data conversion unit 43 includes an audio / visual device system LAN1 and a vehicle control device system L1 which are known in advance.
As shown in FIG. 2, it is possible to generate one frame data of each format of the AN2 and the body equipment LAN 3 and to communicate each one frame data as a packet. If there is a packet that straddles a different LAN depending on the result, one frame data of the destination LAN is generated, and all the packets are put in the data area of the generated one frame data to make a packet at the destination and communicate. The memory 44 stores data communicated via the audio / visual device LAN 1, the vehicle control device LAN 2, and the body device LAN 3, and backs up the processing of the data converter 43.

FIG. 3 is a diagram for explaining the data converter 43 of FIG. 1 in detail. As shown in FIG. 7A, the body equipment LAN 3 is connected to the audiovisual equipment LA.
When a packet is transmitted to N1, the data conversion unit 43
Then, 512 of LAN1 of audio visual equipment system
The 100-bit packet is placed in the bit-length data area, and the packet is transmitted at the transmission speed of the LAN 1 of the audiovisual equipment for communication.

The same applies to the case where packets are communicated from the vehicle control equipment LAN 2 to the audio / visual equipment LAN 1. Also, as shown in FIG. 2B, when a packet is communicated from the audio / visual equipment LAN 1 to the body equipment LAN 3,
The data conversion unit 43 divides the 1000-bit packet of the audio / visual device LAN1 into 12 (1000/88 ≒ 12), and puts the divided packet in the 88-bit data area of the body device LAN3. Communication is performed one after another in packets at the transmission speed of the body device LAN3. In this way, all packets are transmitted in the data area.

Similarly, when a packet is transmitted from the vehicle control device LAN 2 to the body device LAN 3, the 100-bit packet of the vehicle control device LAN 2 is divided into approximately two packets (88 bits). ), And the divided packets are communicated on the data area of the body device LAN3. Further, when a packet is communicated from the audio-visual equipment LAN 1 to the vehicle control equipment LAN 2, the audio-visual equipment L 2
The 1000-bit packet of AN1 is divided into 16 (1000/64 ≒ 16), and the divided packets are transmitted on the LAN2 data area of the vehicle control equipment system.

Further, when a packet is transmitted from the body equipment LAN 3 to the vehicle control equipment LAN 2,
The 100-bit length packet of LAN2 of the vehicle control system is divided into approximately two (in units of 64 bits), and the divided packets are communicated on the data area of LAN3 of LAN2 of the vehicle control system. Also, audio-visual equipment 11, 1 of the audio-visual equipment LAN1.
2, the vehicle control device 21 of the vehicle control device system LAN2,
22 ..., body equipment 3 of body equipment LAN3
1, 32,... Include data extraction units 11A, 1A, 1B that extract one frame data communicated from another LAN from the data area of one frame data communicated from the gateway 4.
2A ..., 21A, 22A ..., 31A, 32A ... are provided. This extraction is easily possible because the format of one frame data to be communicated is known in advance.

Therefore, according to the present invention, the destination L
Since the packet data of the transmission source is transmitted in the data area of one frame data of the AN, the processing is simplified. Next, the data conversion unit 43 generates one frame data of the transmission destination LAN when there is a packet straddling a different LAN according to the monitoring result of the monitoring unit 42, and generates only one data area included in the packet (address area). except for)
Is placed in the data area of the generated one-frame data of the transmission destination, and is transmitted as a packet on the transmission destination network.

More specifically, when a packet is transmitted from the body equipment LAN 3 to the audio / visual equipment LAN 1, the data converter 43 stores the packet in the 512-bit data area of the audio / visual equipment LAN 1. And a packet including a data area having a maximum length of 88 bits, and
Communication is performed at a transmission speed of packets.

The same applies to the case where a packet is transmitted from the vehicle control equipment LAN 2 to the audio / visual equipment LAN 1. When a packet is transmitted from the audio / visual device LAN 1 to the body device LAN 3, the data converter 43 divides the 512-bit data area of the audio / visual device LAN 1 into six (512/88). # 6) The packet including the divided data area is placed on the 88-bit data area of the LAN 3 of the body device, and the L
Communication is performed one after another in packets at the transmission speed of AN3.

Further, when a packet is communicated from the vehicle control equipment LAN 2 to the body equipment LAN 3,
A packet in which the 64-bit data area of LAN2 of the vehicle control system is divided into 88-bit units is transmitted on the data area of LAN3 of the body equipment system. Further, when a packet is transmitted from the audio-visual equipment LAN 1 to the vehicle control equipment LAN 2, the 512-bit data area of the audio-visual equipment LAN 1 is divided into eight (512/64 ≒ 8). ), The packet including the divided data area is transmitted to the LAN 2 of the vehicle control system.
Is communicated on the data area.

Further, when a packet is transmitted from the body equipment LAN 3 to the vehicle control equipment LAN 2,
A packet obtained by dividing the 88-bit data area of the LAN 2 of the vehicle control device system into approximately two and dividing it into 64-bit units,
Communication is carried on the data area of LAN3 of LAN2 of the vehicle control system. In this manner, since the data conversion unit 43 excludes communication other than the data part, the processing is further simplified.

Next, the memory 44 stores the LAN of each audio / visual device system only when there is a packet extending over a different LAN according to the monitoring result of the monitoring unit 42.
1, LAN for vehicle control equipment, LA for body equipment
The data communicated in N3 is stored and the processing of the data conversion unit 43 is backed up. Specifically, from the body device LAN 3 to the audiovisual device LA
When a packet is communicated to N1, the packet is stored in the memory 44.

When a packet is transmitted from the vehicle control device LAN 2 to the audio / visual device LAN 1, the packet is stored in the memory 44. When packets are communicated from the audio / visual device LAN 1 to the body device LAN 3, the memory 4
4 stores the packet. LA for vehicle control equipment
When a packet is transmitted from N2 to the LAN 3 of the body device system, the packet is stored in the memory 44.

Audio / visual equipment LAN1
When a packet is communicated from the LAN to the vehicle control system LAN 2, the packet is stored in the memory 44. When a packet is communicated from the body device LAN 3 to the vehicle control device LAN 2, the packet is stored in the memory 44. In this way, since the packet is stored only when communication is performed over different LANs, the capacity of the memory 44 can be reduced.

[0024]

As described above, according to the present invention, since the communication is performed by placing the source packet or the like in the data area of the frame data of the destination, the protocol can be simplified.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of a gateway according to the present invention.

FIG. 2 is a diagram for explaining data communicated with each of an audiovisual equipment LAN1, a vehicle control equipment LAN2, and a body equipment LAN3.

FIG. 3 is a diagram illustrating a data conversion unit 43 of FIG. 1 in detail.

FIG. 4 is a diagram illustrating a conventional gateway.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... LAN of audio visual equipment (AVC) system 2 ... LAN of vehicle control equipment system 3 ... LAN of body equipment system 4 ... Gateway 11, 12 ... Audio visual equipment 21, 22 ... Vehicle control equipment 31, 32 ... Body Equipment 11A, 12A, 21A, 22A, 31A, 32A Data extraction unit 41 Processing circuit 42 Monitoring unit 43 Data conversion unit 44 Memory

Claims (6)

[Claims] 1. A gateway which enables communication over a plurality of networks for performing packet communication by dividing frame data including control data and data, wherein different networks are provided based on information on a source and a destination of the packet. A monitoring unit that monitors communication performed over a plurality of networks, based on the monitoring result of the monitoring unit, when there is communication of a packet that spans different networks, generating frame data in a format of a transmission destination of the plurality of networks; A gateway, comprising: a data conversion unit that puts the packet in a data area in the frame data and enables packet communication to be performed on a destination network. 2. The data conversion section, when the data length of the packet is larger than the data length of a data area in the frame data, divides the packet and places the divided packet in the data area. The gateway according to claim 1, characterized in that: 3. The data conversion unit according to claim 1, wherein the data conversion unit puts only a data area in the frame data included in the packet on a data area in the frame data of the transmission destination. Gateway. 4. When the data area included in the packet is larger than the data area in the frame data of the transmission destination, the data converter divides the data area included in the packet and transmits the divided data area. 4. The gateway according to claim 3, wherein the gateway is placed in a data area in the previous frame data. 5. A memory for storing data of a packet communicated on a plurality of networks, wherein the memory puts the packet in an area of data in frame data in a destination format by the data conversion unit. The gateway according to claim 1, wherein the gateway is backed up. 6. The method according to claim 6, wherein the memory stores data of a packet communicated on a plurality of networks when there is communication of the packet over different networks based on a monitoring result of the monitoring unit. Item 6. The gateway according to Item 5.