JPH0292128A - Data transmission system in network system - Google Patents

Abstract

PURPOSE:To prevent the generation of the transmission/reception processing of unnecessary data with a trunk network as an object by suppressing the sending to the trunk network of a simultaneous multiple address transmission data when one of plural equipments connected to the same branching line network executes the simultaneous multiple address transmission with all remaining equipments only as an object. CONSTITUTION:The equipment address of the equipment to need the simultaneous multiple address transmission to only all other equipments on a network 21 out of plural equipments 23 and 24 on a bus type network 21 connected with a network adapter 25 is registered to a non-volatile memory 34 beforehand. Consequently, when frame data used with a broadcasting address as a destination address is sent from the register onto the bus type network 21, it is suppressed that the frame data is sent to a ring type network 11. Thus, the generation of the transmission/reception processing of unnecessary data with the trunk network as an object is prevented.

Description

[Detailed Description of the Invention] [Purpose of the Invention (Industrial Application Field) This invention relates to a network system in which a branch network is connected to a trunk network by a network adapter of a station, and in particular, the present invention relates to a network system in which a branch network is connected to a main network by a network adapter of a station, and in particular, - Relates to a data transmission method suitable when frame data whose destination address is a broadcast address is sent.

(Prior Art) In a network system in which a branch network is connected to a trunk network by a station network adapter, the network adapter constantly receives data (frame data) on the connected branch network. Normally, the frame data format applied in a network system consists of a destination address field DA, a source address field SA, and a data field DAT, as shown in Figure 4.
Contains A. Field DA contains an individual address indicating the destination for individual transmission or a broadcast address for simultaneous broadcast transmission (hereinafter referred to as broadcast address).
etc., and the source address indicating the source is set in the field SA.

When a network adapter receives frame data from a branch network, it examines its field DA. If an individual address is set in field DA of the received frame, and the destination indicated by the same address belongs to the connected branch network (own segment), the network adapter will process the received frame because it is a pig transmission within the own segment. is discarded and the frame is not sent to the trunk network. On the other hand, if an individual address is set in field DA of the received frame and the destination indicated by the same address does not belong to the own segment (in other words, if the data is being transmitted to a device belonging to another segment), or the field If a broadcast address is set in DA, the network uses field DA where the address of the segment to which the destination belongs (individual address) or broadcast address is set, field SA where the address of the own segment is set, and the received frame. Transmission frame data (frame data for transmission to the trunk network) consisting of the field DATA set in the field DATA is generated and sent onto the trunk network.

Frame data on the trunk network is received by the network adapter of the station corresponding to the segment if a segment address is set in field DA of the data, and connected to the trunk network if a broadcast address is set. Received by network adapters of all stations.

When the network adapter receives frame data on the trunk network adapter, it sends the contents of the field DATA onto its own segment (connected branch network). Data on this connected branch line will be received by the device at that address if an individual address is set in field DA of the same data, and will be connected to the corresponding branch network if a broadcast address is set. Received by all devices.

There are two purposes for a device connected to a branch network to send frame data using a broadcast address. One is to simultaneously transmit the same data to all devices on all branch networks connected to the main network, and the other is to transmit the same data only to the branch network to which it is connected. This is to transmit the same data to all devices at the same time. However, conventionally, when a broadcast address is set in the field DA of received frame data, the received frame data is sent to the trunk network as described above, regardless of the above-mentioned purpose. In this case, the problem arises that the trunk network is used for meaningless frame transmission.

(Problem to be Solved by the Invention) As mentioned above, conventionally, one of multiple devices connected to the same branch network sends the same data to all remaining devices using a broadcast address (protocast address). If an attempt was made to transmit the data all at once, the data would be treated the same as normal broadcast transmission data and sent to the trunk network, and this unnecessary data transmission would increase the load on the trunk network. There was a problem in that the processing of data that was originally supposed to be transmitted was delayed.

Therefore, in the present invention, when one of a plurality of devices connected to the same branch network attempts to send a simultaneous broadcast to only all the remaining devices, - the broadcast transmission data is sent to the main network. The goal is to make sure that things can be deterred.

[Structure of the Invention] (Means for Solving the Problems) This invention provides a network adapter of each station in a trunk network, in which, among the devices connected to the branch network corresponding to the own adapter, A memory means for pre-registering device addresses of devices that need to perform simultaneous broadcast transmission only to all other connected devices, and a memory device for registering in advance the device addresses of devices that need to perform simultaneous broadcast transmission only to all other devices connected to the same branch network. When the frame data sent above is received, a first determination means determines whether the destination address in the received frame data is a broadcast address; and second determining means that refers to the memory means and determines whether or not a device address that matches the source address in the received frame data is registered in the memory means when it is determined that the received frame data is present. The present invention is characterized in that the received frame data is inhibited from being sent to the trunk network in accordance with the determination result of the second determining means.

(Function) According to the above configuration, among the devices on the branch network connected to the local network adapter, the devices need to perform simultaneous broadcast transmission only to all other devices connected to the same branch network. By registering the device address in the memory means in advance, when this registered device sends frame data using the broadcast address as the destination address on the branch network, this frame data is sent to the main network. It is possible to prevent this from happening.

(Embodiment) Fig. 1 is a block diagram showing an embodiment of a network adapter directly related to the present invention, and Fig. 2 shows an embodiment of a network system equipped with a station having the network adapter shown in Fig. 1. It is a system configuration diagram.

In FIG. 2, reference numeral 11 denotes a ring network using an optical fiber cable as a trunk network;
12 to 17 are stations (ST) interconnected by the ring network 11; 21.22 is a branch network such as a bus network, 2
3.24 is equipment such as a terminal connected to the bus type networks 21 and 22. The device 23 is, for example, a server (file server) equipped with a disk device, etc.
Reference numeral 4 denotes a client that reads data from a disk device included in the device 23, for example. Bus network 21.
22 are connected to the ring network 11 by network adapters 25 and 26 called ring bus controllers (RBCs) provided at the station 1213. In FIG. 2, the bus network connected to stations 14-17 is omitted. Note that the number of network adapters is not limited to one for each station.

The network adapter 25 of the station 12 is
It is configured as shown in the figure. In the figure, 31 is a CPU that controls the entire network adapter 25;
is a program ROM in which a microprogram for defining the operation of the CPU 31 is stored. 33 is CPU
31 is a RAM in which a work area to be used, a data buffer area, an address translation buffer area for storing address translation information including address pairs of device addresses and segment addresses, etc. are placed; 34 is a bus connected to the network adapter 25; A memory, for example, a non-volatile memory, for pre-registering the device address of a device among a plurality of devices 23, 24 on the same network 21 that requires simultaneous broadcast transmission only to all other devices on the same network 21. It is. 35 is a device such as LED, timer, interrupt, etc. (■
10 devices), 3B is CPU31 and program ROM
32, an internal bus interconnecting the RAM 33, nonvolatile memory 34, I10 device 35, etc.; 37, the CPU 3;
1 and a bus controller 38 which will be described next. 38 is a bus controller for controlling transmission and reception for the bus network 21; 39;
40 is shared by the bus controller 38, CPU 31, etc., and is used as a transmission/reception switch (frame data) between the bus network 21 and the ring network 11. It is a shared memory for storing.

Next, the operation of one embodiment of the present invention will be explained with reference to the flowchart of FIG.

First, it is assumed that frame data in the format shown in FIG. 4 is sent onto the bus network 21 from the device 23 connected to the bus network 21. Bus network 2
1 is received by the bus controller 38 (step Sl). The bus controller 38 stores the frame data received from the bus network 21 in the shared memory 4o, and notifies the CPU 31 of the completion of the storage via the shared bus 37.

In response to the completion notification from the bus controller 38, the CPU 31 reads the contents of the destination address field DA in the received frame data from the bus network 2I stored in the shared memory 4o, and determines whether the contents are a broadcast address or not. (Step S)
2). If the content of the field DA is a broadcast address, the CPU 31 takes in the content of the source address field SA in the received frame data from the bus network 21 stored in the shared memory 4o, and uses the same content to create a non-volatile address. By searching the nonvolatile memory 34, it is determined whether an address (equipment address) matching the same content (source address) is registered in the nonvolatile memory 34 (step S3).

If a device address that matches the source address set in the field SA in the received frame data is registered in the nonvolatile memory 34, the CPU 31 sends the device from the device indicated by the same address (device 23 here). It is sent to the bus type network 2I (bus controller 3
8 to the shared memory 40) is data that needs to be broadcasted only to all other devices on the bus network 21. Suppressing sending to the ring network 11 (
Step S4). In this case, since the broadcast transmission data from the device 23 (targeting all other devices connected to the bus network 21) is not sent to the ring network 11, the ring network 11 is wasted. This can prevent the ring network 11 from being used, and improves the usage efficiency of the ring network 11.

On the other hand, if the device address that matches the source address set in the field SA in the received frame data is not registered in the nonvolatile memory 34 (if the determination in step S3 is No), this Received frame data is handled in the same way as before. That is, the CPU 31
Assuming that the received frame data is data that should be simultaneously broadcast to all devices on all bus networks connected to the ring network 11, a broadcast address is set in the field DA, and the broadcast address is set in the field SA.
Header information in which the address of the own segment (an address specific to the bus network 21) is set is added to the beginning of the received frame data to generate a frame for transmission, and the ring controller 39 sends the frame to the ring network 1.
1 (step S5). Also, when the contents of the destination address field DA in the received frame data is not a broadcast address (that is, when the determination in step S2 is No), the received frame data is handled in the same way as before, but the operation in this case is Since it is not directly related to the present invention, the explanation will be omitted.

Note that in the embodiment, a plurality of devices 2 on the bus network 21 connected to the network adapter 25
3.24, by registering in advance the device address of a device that requires simultaneous broadcast transmission only to all other devices on the same network 21 in the non-volatile memory 34, it is possible to transmit the device address from this registered device to the bus network 21. Above, we have explained the case where, when frame data is sent using a broadcast address as the destination address, the frame data is prevented from being sent to the ring network 11. It is possible to achieve this effect. In other words, in this method, the first broadcast address indicating that the frame data is to be simultaneously transmitted to all devices on all bus networks connected to the ring network 11 is used as a broadcast address, and the device itself A second broadcast address is prepared to indicate that the frame data should be broadcasted only to all devices on the connected bus network, and these two types of broadcast addresses are used properly to transmit the field DA in the received frame data. If a broadcast address is set in , the process proceeds to step S4 or step S5 by determining which of the above two types of broadcast address it is instead of step S3 in FIG. .

With this method, two types of simultaneous broadcast transmission are possible even with the same device.

[Effects of the Invention] As detailed above, according to the present invention, when one of a plurality of devices connected to the same branch network attempts to broadcast broadcast to only all remaining devices, - Since it is possible to prevent simultaneous broadcast transmission data from being sent to the trunk network, it is possible to prevent unnecessary data transmission and reception processing that targets the trunk network, and it is possible to achieve efficient operation of the trunk network.

[Brief explanation of the drawing]

FIG. 1 is a block configuration diagram showing an embodiment of a network adapter directly related to the present invention; FIG. 2 is a system configuration diagram showing an embodiment of a network system equipped with a station having the network adapter of FIG. 1; FIG. 3 is a flowchart for explaining the operation, and FIG. 4 is a format diagram of frame data. 11...Ring network (trunk network)
12-17...Station (ST), 21.22
...Bus type network (branch line network), 23
, 24... Device, 25. 28... Network adapter, 31... CPU, 34... Non-volatile memory,
38... Bus controller, 39... Ring controller, 40... Shared memory. Applicant's agent Patent attorney Takehiko Suzue

Claims (1)

[Scope of Claim] A network system comprising a plurality of stations interconnected by a trunk network, and independent branch networks each connected to the trunk network via a network adapter of each station, comprising: A memory means for pre-registering device addresses of devices that need to perform simultaneous broadcast transmission only to other devices connected to the same branch network among the devices connected to the branch network corresponding to the own adapter. and a receiving means for receiving frame data sent onto the branch network from a device connected to the branch network corresponding to the own adapter, and a destination address in the frame data received by the receiving means is simultaneously broadcast. a first determining means for determining whether or not the address is a broadcast address for transmission; and when the first determining means determines that the address is a broadcast address for transmission, the memory means is referred to; second determining means for determining whether or not a device address matching the source address in the frame data received by the means is registered in the memory means; A data transmission method in a network system, characterized in that data transmission to the trunk network is inhibited depending on a determination result of the second determining means.