JPH04176227A - How to monitor network communication data - Google Patents

Abstract

PURPOSE:To monitor a communication data between stations generated by the user by utilizing a means of group multiple address communication in a LAN to fetch the communication data between specific stations to a monitor station thereby utilizing a work station and a personal computer. CONSTITUTION:Each station address is decided in a way that a station 1 and a monitor station belong to a same reception group and a station 2 and the monitor station belong to a same reception group in the case of monitoring. Before the communication is implemented among the stations, an individual address of each station stored in each station is revised into a group address according to the decision. Thus, the communication data among the stations is monitored.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for monitoring communication data between distributed systems connected to a workpiece.

[Conventional technology]

Conventionally, there have been two main methods for monitoring communication data between specific stations connected to a local area network (hereinafter abbreviated as LAN).

One method is to incorporate a monitor program into the station to be monitored. Specifically, this is a method of rewriting the communication control program, operating system, or application program within the station to call the monitor program. The communication data received by the monitor program called as a result of modification is recorded in a file or memory.

Another method is to connect an online scope dedicated to monitoring or LA, N monitors for monitoring.

[Problem to be solved by the invention]

A major problem with the first conventional method is that the existing program must be rewritten. Generally, rewriting a program is not easy. In rare cases, this may not be possible. For example, there may be cases where it is unknown where to rewrite an existing program, or there may be cases where only object programs exist and cannot be changed.

Furthermore, since a wide variety of stations are connected to the LAN, some stations may have insufficient memory for the monitor program to record monitoring results, such as stations with small memory capacity or stations without magnetic disks.

The second conventional method has a problem in that when a dedicated I/AN monitor is used, only stations having the same communication protocol prepared by the manufacturer can be monitored. Additionally, a dedicated LAN
Another problem is that monitors are expensive and cannot be easily obtained by users.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for monitoring communication data between stations created by a user using commonly used workstations and personal computers.

[Means to solve the problem]

The above object is achieved by providing a method for capturing communication data between specific stations into a monitor station by utilizing means of group broadcast communication in a LAN.

[Effect]

Generally, communication between stations is performed by specifying a destination station. At that time, a station address uniquely assigned to each station within the LAN is specified. The address is called an individual address, and the means of specifying the individual address and communicating is called individual communication.

In the case of individual communication, communication is performed only between specific stations, and even if the monitor station is connected to the LAN, the monitor station cannot receive the information.

However, a communication means called group broadcast communication exists in the LAN. This is a means of communicating by specifying addresses for multiple stations instead of specifying individual addresses as destination addresses. An address that addresses multiple stations is called a group broadcast address (or group address).

Therefore, if you set the station to be monitored and the monitor station in the same reception group, and switch to group broadcast communication instead of individual communication during monitoring, the monitor station will be able to monitor the communication between the specific stations to be monitored. Data can now be received.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a conceptual diagram for explaining means of group broadcast communication. In Figure 1, 1 indicates the station to be monitored, 2 indicates the other station to be monitored, and 3 indicates the station to be monitored.
is the monitor station, 4 is the common cable, 5 is the cable connecting station 1 to common cable 4,
Reference numeral 6 indicates a cable that connects the station 2 to the common cable 4, and 7 indicates a cable that connects the monitor station 3 to the common cable 4.

Generally, communication is performed by means of individual communication that specifies the destination station. For example, when transmitting data from station 100 to station 2, the destination address of the communication data is an address uniquely assigned within the LAN of station 2, that is, an individual address. When the communication data flows on the common cable 4, it is taken in by a station having a station address that matches the destination address. That is, in the example of FIG. 1, the signal is received by station 2 through the cable 6 of station 2.

Further, when data is transmitted from station 2 to station 1, the destination address of the transmitted data becomes the individual address of station 1, and as a result, station 1 receives the data in the same way.

As long as this means of individual communication is used, the cable 7 of the monitor station 3 can be connected to the common cable 4 as shown in Figure 1.
Even if connected to Monitor Station 3, Monitor Station 3 will be connected to Station 1.
It is not possible to receive and monitor communication data between and station 2.

Therefore, the present invention provides a system in which individual communication is performed using the destination address as the individual address of the destination station.
At the time of monitoring, the destination 71-res is used as a group address to perform group broadcast communication, so that the monitor station can also receive communication data between stations.

The outline of the method is as follows. During monitoring, each station address is determined so that station] and monitor station 3 are placed in the same receiving group, and station 2 and monitor station 3 are placed in the same receiving group. Before communication occurs between each station, the individual address of each station stored in stage 3 is changed to a group address according to the above determination. A more detailed explanation will be given with reference to FIG. 2 and subsequent figures.

Although FIG. 1 illustrates a network configuration of two stations, the present invention is not limited to two stations. This is because the number of stations that can be set in the same reception group as monitor stage 9-3 is two or more.

FIG. 2 shows a communication data format when communication is performed between stations. In Figure 2-(a), 10 is the entire communication data format, 11 is the destination address, 12 is the source address, 13 is the data length, 1
4 indicates communication data. FIG. 2-(b) shows the detailed format of the destination address 11. In Figure 2-(b), 15 is the 46-bit address and 16 is the U/
17 indicates the L flag, and 17 indicates the i/G flag, respectively.

A 46-bit address 15 is an address uniquely assigned to each station.

The I10 flag 16 is the L S in the destination address 11.
B (Least 51gn1ficant Bjt)
This flag indicates whether the destination address 11 is an individual address or a group broadcast address. I/G
When the flag is II OII, the destination address 11 indicates an individual address, and when the I10 flag is "1", the destination address 11 indicates a group broadcast address.

The U/L flag 17 is located on the positive side of the I10 flag, and is a flag indicating whether the destination 71-response 11 is a global address that is unique throughout the world or a local 71-response that is unique only within the LAN. be. When the U/L flag is u OII, the destination address 11 indicates a global address, and when the U/L flag is 111 II, the destination address 11 indicates a local address.

In the present invention, when monitoring, the I10 flag is set to 101.
Change the destination address so that it becomes II so that monitor station 3 can also receive it.

FIG. 3 shows a hardware configuration diagram of a monitor station implementing the present invention. In Figure 3, 2° is the CPU, 2°
1 is a memory, 22 is a LAN adapter, 23 is a keyboard, 24 is a display, and 25 is a magnetic disk.

If the destination address 11 in FIG. 2 is an individual address, the LAN adapter 22 receives communication data and inputs it into the memory 21 if it matches the station address assigned to its own station. Further, if the destination address 11 is a group broadcast address, the group address assigned to the own station is ANDed with the 46-bit 1-address 15, and if it is other than LL OI + group, the communication data is received and the memory 21 L A
N adapter 22 operates.

As mentioned above, there are various types of stations connected within a LAN. For example, the station to be monitored may be a stage 1 with the same configuration as shown in FIG. 3, a station without a keyboard 23 or a display 24,
It does not matter if the station does not have the magnetic disk 25. The minimum configuration is CPU 20, memory 21 and L
The present invention can be applied to any station that has an AN adapter 22 and whose station address can be easily changed.

Figure 4 shows memory 2 of monitor station 1 or 2.
1 shows a rough 1 hardware configuration diagram in 1. In FIG. 4, 31 is an operating system, 32 is a communication control program, 33 is a station address (called a physical address) uniquely assigned to the own station, and 34 is a group 71 assigned to the own station. −
35 is the destination station, station 71.
36 indicates a station address table in which responses are stored, and 36 indicates an application program.

FIG. 5 shows a station address definition file. In FIG. 5, 40 indicates a station address definition file stored on the magnetic disk 25, 41 indicates a station name, and 42 indicates a station 71-less corresponding to the station name.

Information in the station definition file 40 is staged by the communication control program when the station is powered on;
read into the address table 35.

FIG. 6 shows an address initialization file that stores station addresses assigned to each station. That is, 5O-(a) in FIG. 6-(a) is station 1, 50-(b) in FIG. 6-(b) is station 2, and 5O-(c) in FIG. ) indicates an address initialization file stored in each magnetic disk 25 of the monitor station 3. 5l-(a
) to station 1, 5l-(b) to station 2
5l-(c) is a station address uniquely assigned to each monitor station 3, that is, a physical address. 52-(a) is a group address assigned to station 1, 52-(b) is assigned to station 2, and 52-(c) is assigned to monitor station 3, respectively.

Address initialization file 50-(a), (b).

The information in (c) is read by the communication control program when each station is powered on, and the physical address 50-(a), (b) in each file is read.

(c) is set as the physical address 33 of each station. Also, the group address 5 in each file
2- (a), (b), and (c) are set to the group address 34 of each station.

When there is a communication request from the application program 36 specifying a destination station, the communication control program obtains the station address of the specified destination from the station address table 35 and converts it into the communication data format shown in FIG. 10 and instructs the LAN adapter 22 to send it.

When normal communication is carried out between stations, the station address 42 in FIG. 5 stores the individual address of each station. For example, in the example network configuration shown in FIG. 1, the station address 41 of station 1 is
II 10 II is stored in the station address 41 of station 2, and 20'' is stored in the station address 41 of station 2. In this case, when each station is powered on, the individual address of each station is stored in the station address table 35 of each station. .

On the other hand, corresponding to the above stage 1 address definition file 40, the physical address 5-(a) in FIG.
0" is stored in 52-(b), 20" is stored in 52-(c), and "30" is stored in 52-(c). Also, in normal individual communication, the group address is meaningless, so 5 in Figure 6
2-(a),(b).

In (c), 110'' is stored respectively.

In this state, for example, from station 2 to station 1
When a communication is performed, the destination address 1-1 of the communication data becomes "10'', and even if the monitor station 3 is connected to the LAN, it is impossible to receive the communication data.

However, for example, if the station address 42 of station 1 in FIG. 5 is replaced with "11" and the station address 42 of station 2 is replaced with 1'21", the station address will be
Changes to group broadcast address with +1. When each station is powered on in this state, group broadcast addresses are automatically stored in the station address table 35 of each station. As a result, for example, when a communication is made from stage 2 to stage 1,
The destination address 11 of the communication data becomes "11", and the means of individual communication is switched to the means of group broadcast communication.

Furthermore, group address 52-(a) in FIG.
110”, the group address 52-(b) is LL
20 II, the group address 52-(c) is 30"
, each station receives communication data with a specific group broadcast address.

For example, when a communication is made from station 2 to station 1, the destination address 11 of the communication data is LL.
11 II, and becomes the group broadcast address. When the group broadcast address in the communication data and the group 71 heres 34 of each station are ANDed, II OI
Station 1 and monitor station 3 other than + can receive the signal.

Also, when communication is performed from station 1 to station 2, the destination address 11 of the communication data is
21 II, and becomes a group broadcast address. When the group broadcast address is ANDed with the group address 34 of each station, stations 2 and monitor stations 3 other than "O" can receive the signal.

In other words, the monitor station 3 becomes a monitor target if the group address 52-(c) is determined by ANDing with the group addresses assigned to all the stations to be monitored so that LL i II is always obtained. It becomes possible to monitor communication data going back and forth between all stations.

Furthermore, if the group address 52-(c) is determined to be in the same reception group as a specific station, it is also possible to monitor communication data between specific stations.

〔Effect of the invention〕

According to the present invention, it is possible to easily monitor communication data using a data processing device such as a personal computer or workstation, which is widely used in communication, without modifying the program of a communication system that functions on a LAN created by a user. become.

In addition, it is possible to monitor the target communication system by connecting a station to be monitored or a monitor station to a LAN that is already connected to a station and is actually in operation without stopping the LAN. be.

In addition, since no special procedures are added to the communication between the monitored stations, the same communication data as in the real environment can be used without degrading performance due to monitoring. Can be monitored.

[Brief explanation of the drawing]

Fig. 1 is a conceptual diagram for explaining group broadcast communication, Fig. 2 is a diagram showing the communication data format, Fig. 3 is a block diagram of bars 1 to 3 of the monitor station, and Fig. 4 is a diagram of the internal memory. FIG. 5 is a diagram showing a station address definition file, and FIG. 6 is a diagram showing an address initialization file. 1 Monitor target station, 2...Other monitor target stations, 3-Monitor station, 4 common cable, 5...Station 1 cable, 6...Station 2 cable, 7...Monitor station 3 cable, 10... To communication data format +, 11
Destination 71-Response, 12...Communication source address, 20...
・CPU, 21...Memory, 22LAN adapter, 2
3. Keyboard, 24. Display, 25. Magnetic disk, 31. Operating system, 32
・Communication control program, 33...Physical address, 34.
Group address, 35...Station address table, 36...Application program, 40...Station address definition file, 50-a, 50-b, 50-
a・Each 0) \Q m”) spatula area ”Mi () '-C'J
−ゝ ゝ ＼ ＼

Claims (1)

[Claims] 1. In a network system in which data is transferred by specifying a station address, a monitor station is connected to the network, and an individual address uniquely assigned to each station is used to transfer data to a group of multiple stations. 1. A method for monitoring communication data in a network, characterized in that the communication data of a group broadcast communication is monitored by carrying out group broadcast communication between stations to be monitored. 2. Divide the stations to be monitored into groups, assign a unique group broadcast address to each group, set a group address for stations to receive communication data of a specific group broadcast address, and 2. The monitor station according to claim 1, wherein when receiving a broadcast address, the address of the monitor station is replaced with a group address, and all communication data of group broadcast communication between all stations to be monitored is monitored. A method for monitoring network communication data. 3. Divide specific stations among the stations to be monitored into groups, assign a unique group broadcast address to each group, and when receiving communication data of all group broadcast addresses, 2. The network communication data monitoring method according to claim 1, wherein communication data of group broadcast communication between specific stations among the monitored stations is monitored by replacing the address with a group address.