JPH05160836A - Loopback test system for local area network - Google Patents

Abstract

PURPOSE:To improve the quality by executing the loopback test without storing a physical address of plural bridges connecting to a network to a memory so as to prevent the increase in the memory capacity. CONSTITUTION:A control section 11 of a sender side equipment 3 sets a physical address of the equipment 3 to a destination address (DA) 33 and a source address (SA) 35 of a MAC frame 31. The set frame 31 is outputted to a transmission section 15 by the control section 11 and sent to a loopback device 5 via a network interface (IF) 7 and a network 1. A control section 29 of the device 5 sets '1' to a register 27 of a reception mode designation section 25 to allow the IF 17 to receive the frame 31. The control section 29 generates an end interrupt to confirm the area of the reception buffer to read the content of the buffer. The control section 29 compares the address stored in the reception buffer with a DA 33 set in the received frame 31 and outputs the information of the frame 31 to the transmission section 23 when they are unmatched and the DA33 and the SA35 are matched.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a plurality of bridges connected to a network, and, of the plurality of bridges, a bridge of a transmitting station transmits a frame to a bridge of a returning station via the network, and the returning is performed. Among the loopback test methods of the local area network, which comprises means for transmitting the frame from the bridge of the transmitting station to the bridge of the transmitting station through the network, particularly, by preventing the memory capacity of the bridge of the transmitting station from increasing, the quality is improved. The present invention relates to a loopback test method for a local area network for improving the performance.

[0002]

2. Description of the Related Art In recent years, a local area network (hereinafter referred to as LAN), which is a computer network in a company in which a plurality of offices and factories are connected to each other, has become widespread in offices and the like.

In the above LAN, a loopback test is generally used as a means for confirming the connection and transmission / reception functions of a plurality of bridges connected to the network.
In the above-mentioned loopback test, among the plurality of bridges connected to the network, the transmitting side device, which is the bridge of the transmitting station, applies the MAC to the destination address (hereinafter, referred to as DA) 33 of the MAC frame 31 shown in FIG.
The physical address indicating the unique address of the loopback device that is the bridge of the loopback station that is the transmission destination of the frame 31 is set. Further, the transmitting side device sets the source device 35 (hereinafter referred to as SA) 35 of the MAC frame 31 to the physical address of the transmitting side device, and transmits it to the loopback device via the network. The MAC frame 31 transmitted via the network is received by the loopback device. The loopback device that has received the MAC frame 31 uses the DA set in the MAC frame 31.
33 and SA 35 are exchanged and transmitted to the transmission side device via the network. Although the loopback test is executed by the MAC frame 31 being received by the transmission side device via the network, the physical address of the loopback device is required in advance for the transmission side device, so that an increase in memory capacity is prevented. It wasn't easy to do.

[0004]

However, in the conventional loopback test, since the transmitting side device needs to store the physical address of the loopback device in advance, if a large number of bridges are connected to the network, the loopback test will be performed. Since the physical address of the bridge is stored in the memory, there is a problem that the memory capacity is increased.

The present invention has been made to solve such a conventional problem, and an object thereof is to perform a loopback test without storing the physical addresses of a plurality of bridges connected to a network in a memory. By executing the method, it is possible to prevent an increase in memory capacity and provide a high-quality loopback test method for a local area network.

[0006]

In order to achieve the above-mentioned object, the present invention provides a plurality of bridges connected to a network, and a frame from a bridge of a transmitting station to a bridge of a returning station among the plurality of bridges. In the loopback test method of the local area network, which comprises means for transmitting through the network and transmitting the frame through the network from the bridge of the loopback station to the bridge of the transmitting station Transmitting means for setting a physical address indicating a bridge of the transmitting station to a source address and a destination address of the frame and transmitting the physical address to the bridge of the returning station via the network, and a bridge of the returning station via the network. Receives all frames transmitted Means and a source address and a destination address of a frame received by the receiving means, and when the source address and the destination address match, the frame is transmitted to the bridge of the transmitting station via the network. It is a gist to have the means to do.

[0007]

With the above configuration, the physical address indicating the unique address of the bridge of the transmitting station is set to the source address and the destination address of the frame transmitted from the bridge of the transmitting station. The set frame is transmitted from the network.

On the other hand, the bridge of the receiving station receives all the frames transmitted through the network. The source address and destination address of the received frame are compared. When the source address and the destination address match by comparison, the received frame is transmitted via the network, so that it is possible to prevent the memory capacity of the bridge of the transmitting station from increasing.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a loopback test system for a local area network.

In FIG. 1, of the plurality of bridges connected to the network 1, the transmitting side device 3 and the transmitting side device 3 which are the bridges of the transmitting station at the time of the loopback test and are used as means for confirming the connection and transmitting functions. A loopback device 5 that is a bridge of a loopback station that loops back a MAC frame 31 to be described later transmitted from the network 3 is connected to the network 1.

The transmission side device 3 has a network interface 7, a physical address designation unit 9, a control unit 11, a reception unit 13 and a transmission unit 15.

The network interface 7 is
Transmission and reception are performed between the transmission side device 3 and the loopback device 5 and the like connected to the network 1. Physical address designation unit 9
Should be received by the network interface 7
Specify the C frame.

The control unit 11 controls the entire transmission side device 3, and when executing a loopback test, the destination address (hereinafter referred to as DA) 33 and the source of the MAC frame 31 shown in FIG. An address (hereinafter, referred to as SA) 35 is set to a physical address which is a unique address indicating the transmission side device 3. Here, the MAC frame 3 shown in FIG. 3 will be described. In the MAC frame 31, first, a preamble for establishing bit synchronization is set, an SFD indicating the end of the preamble is set, DA 33 of the destination address of the MAC frame 31 is set, and the MAC frame 3 is set.
SA35 of the source address of 1 is set, the information of the message body is set, and finally the CRC of the cyclic redundancy code for detecting a bit error is set.

The receiving unit 13 controls the reception of the network interface 7 and handles the MAC frame received via the network interface 7, and outputs it to the control unit 11. The transmission unit 15 controls the transmission of the network interface 7 and handles the MAC frame 31 transmitted via the network interface 7, and outputs the MAC frame 31 to the network interface 7.

On the other hand, the loopback device 3 is a dedicated device or a device set to the loopback mode by a higher level protocol. The network interface 17, the physical address section 19, the receiving section 21, and the transmitting section 23 of the folding device 5 have the same functions as the network interface 7 and the like of the transmitting section 3. The reception mode designation unit 25 includes a register 27 and switches the reception mode of the network interface 17. The reception mode designating section 2
In the case of executing the loopback test, when the register 27 is set to "1" by the control unit 29, for example, all the MAC frames 31 transmitted from the network 1 are received by the network interface 17. on the other hand,
In the case other than the loopback test, the control unit 29 sets the address 2
7 is set to, for example, "0", and the network interface 17 enters the normal reception mode.

The control unit 29 controls the entire loopback device 5, and in the case of the loopback test, the register 27 of the reception mode designating unit 25 is set to "1" and received via the network interface 17. Then, an interrupt by software is generated, and the address stored in the reception buffer (not shown) is compared with the DA 33 set in the received MAC frame 31. If it is different from the address of the reception buffer by comparison, the control unit 2
9 is the DA 33 set in the MAC frame 31
And SA35 are compared. DA33 and SA3 by comparison
When it matches with 5, the control unit 29 outputs the received MAC frame 31 to the transmission unit 23 to transmit the MAC frame 31 to the transmission-side apparatus 3 that is the transmission source via the network interface 17 and the network 1.

Next, the operation of this embodiment will be described with reference to the flowchart of FIG.

First, when the system of the transmission side device 3 and the loopback device 5 connected to the network 1 is activated to execute the loopback test, the control unit 11 of the transmission side device 3 is executed.
Sets the physical address of the device 3 in DA 33 and SA 35 of the MAC frame 31. MAC set
The control unit 11 outputs the frame 31 to the transmission unit 15 and transmits the frame 31 to the folding device 5 via the network interface 7 and the network 1 (step 100).

On the other hand, the control unit 29 of the loopback device 5 sets "1" in the register 27 of the reception mode designating unit 25 and causes the network interface 17 to receive the MAC frame 31 transmitted from the network 1. MAC
Upon receiving the frame 31, the control unit 29 generates a completion interrupt, confirms the area of the reception buffer (not shown), and reads the reception buffer (steps 110 to 110).
140).

After reading the reception buffer, the control unit 29
The address stored in the reception buffer is compared with the DA 33 set in the received MAC frame 31, and when they do not match, the DA 33 and SA 35 are compared. When DA33 and SA35 match by comparison, the control unit 29 sets the received data of the information set in the MAC frame 31 in the transmission buffer and then sets the M
The AC frame 31 is output to the transmitter 23. Transmission unit 23
The MAC frame 31 output to is transmitted to the transmission side device 3 indicated by the DA 33 via the network interface 17 and the network 1 (steps 150 to 17).
0).

As a result, the loopback test of the operation confirmation test of the bridge connected to the LAN is performed as in the conventional LAN.
Since it is not necessary to store the physical address of the bridge connected to the memory in the memory, it is possible to prevent the memory capacity from increasing.

The present embodiment can be applied not only to the MAC bridge device but also to various bridges, and even if the loopback test is executed during the normal operation, it does not affect the transmission / reception processing with respect to the network 1. ..

[0024]

As described above, according to the present invention, since the physical address indicating the bridge of the transmitting station is set in the source address and the destination address of the frame, the physical addresses of a plurality of bridges connected to the network are set. By executing the loopback test without storing it in the memory, it is possible to prevent the memory capacity from increasing and improve the quality.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a loopback test method for a local area network according to the present invention.

FIG. 2 is a flowchart showing the operation of the present invention.

FIG. 3 is a diagram showing a MAC frame.

[Explanation of symbols]

 1 network 3 transmitting side device 5 loopback device 7,17 network interface 11,29 control unit 25 reception mode designating unit 27 register

Claims (1)

[Claims] 1. A plurality of bridges connected to a network, a frame of the plurality of bridges of a transmitting station is transmitted from a bridge of a transmitting station to a bridge of a returning station via the network, and the bridge of the returning station transmits the frame to the transmitting station. In the loopback test method of the local area network, comprising: a means for transmitting the frame to the bridge via the network, the source station and the destination address of the frame transmitted from the bridge of the transmitting station are set to the bridge of the transmitting station. Transmitting means for setting the physical address shown and transmitting to the bridge of the return station via the network; receiving means for receiving all frames transmitted to the bridge of the return station via the network; Of frames received by the means Means for comparing the source address and the destination address, and transmitting the frame to the bridge of the transmitting station via the network when the source address and the destination address match. Local area network loopback test method.