JPH0378341A - Bridge device - Google Patents

Abstract

PURPOSE:To obtain sufficient data transfer efficiency in a network system having a large number of terminals by dividing and constructing transfer data bases for respective input ports and transfer-controlling data only by means of referring to the data bases corresponding to the input ports receiving data. CONSTITUTION:For transferring a data packet between LAN 2 and 3, two transfer data bases 12a and 12b are provided. When data is received in an input port P1, the first transfer data base 12a corresponding to the input port P1 is searched and whether the opposite destination address of input data, namely, an address 'B' is registered in the transfer data base 12a or not is judged. Since addresses 'A' and 'B' are registered in the transfer data base 12b in this example, that a port number corresponding to the opposite destination address 'B' is equal to a port number receiving input data is judged, and that the opposite destination address 'B' is connected to the same port P1 which is the same as the transmission source address 'A' is recognized. Thus, only the address of the data base corresponding to the input port receiving data is searched.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention relates to a bridge device, and particularly relates to a technology for constructing a transfer database used in a bridge device, a server, etc. that connects two LANs. .

(Prior Art) Generally, a network system including a bridge device is
It is configured as shown in FIG. In the figure, 1 is a bridge device, and 2 and 3 are branch LANs.

4.5 is a terminal device connected to LANI, 6.7 is LA
This is a terminal device connected to N2. The bridge device l is
A transfer database as shown in FIG. 6 is used to control data transfer between the two LANs 2.3.

In the transfer database, the address of each terminal device, the input port number to which each terminal device is connected, and the elapsed time (timer) since the last data packet was transmitted from each terminal device are registered.

Next, the data transfer control operation of the bridge device 1 using the transfer database will be explained. For example, address II
Consider data transfer from the terminal device 4 of A I+ to the terminal device 6 of address "C". In this case, the data packet sent from the terminal device 4 is received by the first input port, and the destination address of the data packet is indicates “C”, so refer to the transfer database and find the address “C”.
“, which boat is connected to is searched.

As a result, it is recognized that the terminal device 6 with address "C" is connected to the second boat, and the data packet from the terminal device 4 is sent to the second boat. As a result, data is transferred to the terminal device 6 at address "C".

Next, from the terminal device 4 at address “A” to address “B”
” consider data transfer to the terminal device 5.

In this case, the data packet transmitted from the terminal device 4 is received by the first input port, and the destination address of the data packet indicates "B", so refer to the transfer database to determine which address "B" is. A search is made to see if it is connected to a boat.

As a result, it is recognized that the terminal device 5 with address "B" is connected to the same first port as the transmission source terminal device 4, and the data packet from the terminal device 4 is transferred to the bridge device 1.
Discarded internally.

In this way, in the conventional bridge device, LANI.

The addresses of all terminal devices of 2 are registered in the transfer database, and data transfer is controlled by searching the transfer database for the boat number corresponding to the destination address of the received data packet.

However, in such a bridge device, as the number of terminal devices increases, the amount of information registered in the transfer database increases, so there is a drawback that it takes a lot of time to search for an address. This causes a reduction in data transfer efficiency.

(Problems to be Solved by the Invention) Conventional bridge devices have the drawback that it takes time to search for an address, and sufficient data transfer efficiency cannot be obtained.

The present invention has been made in view of the above points, and an object thereof is to provide a bridge device that can shorten address search time and achieve sufficient data transfer efficiency even in a network system with a large number of terminal devices. purpose.

[Configuration of the Invention (Means for Solving the Problems) A bridge device of the present invention includes first and second input ports, each connected to a corresponding network, and a terminal corresponding to the first input port. a first database storage means in which address information of the terminal corresponding to the second input port is registered; a second database storage means in which address information of the terminal corresponding to the second input port is registered; Select one of the first and second database storage means according to the input port that received the data, and execute data transfer control by referring to the address information registered in the selected database storage means. It is characterized by comprising a control means.

(Operation) In this bridge device, the transfer database is divided and constructed for each input port, and data transfer control is executed simply by referring to the database corresponding to the input port that received the data. therefore,
Compared to the conventional technology, the average address search time can be reduced by about half, and sufficient data transfer efficiency can be achieved even in network systems with a large number of terminals.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a bridge device according to an embodiment of the present invention. This bridge device 11 is a LAN2.

3 to interconnect the two input ports P1゜P2
have. A LAN 2.3 is connected to each of the boats Pi and P2.

The LAN 2 is provided with a terminal device 4 to which an address "A" is assigned and a terminal device 5 to which an address "B" is assigned. On the other hand, LAN3 has the address "
The terminal device 6 to which address “C” is assigned and the address “D
A terminal device 7 to which " is assigned is provided.

The bridge device 11 has two transfer databases 12 in order to control the transfer of data packets between the LANs 2.3 and 2.3.
a, 12b.

The first transfer database 12a has a first input port P.
1, and as shown in Figure 2 (A),
The address of each terminal device connected to input port P1 and the elapsed time (timer) since the last data packet was transmitted from each terminal device are registered. In FIG. 2(A), the address “
The elapsed time since the last data packet was transmitted from the terminal devices 4 and 5 of A and B is tl, respectively.

The case of t2 is shown.

The second transfer database 12b has a second input port P.
2, and as shown in Figure 2 (B),
The address of each terminal device connected to input port P2 and the elapsed time (timer) since the last data packet was transmitted from each terminal device are registered. In FIG. 2(B), the address “
A case is shown in which the elapsed time since the last data packet was transmitted from the terminal devices 6 and 7 of C" and "D" is t3 and t4, respectively.

Next, data packet transfer control by the bridge device 11 using these two transfer databases 12a and 12b will be explained with reference to the flowchart in FIG.

First, consider a case where the terminal device 4 with address "A" sends a data packet to the terminal device 5 with address "B". In this case, since the data packet from the terminal device 4 is input to the bridge device 11 via the first input port pt, it is determined that data has been received at the input port P1 (step AI). When data is received at the input port P1 in this way, the first transfer database 12a corresponding to the input port P1 is searched (step A
3) It is determined whether the destination address of the input data, that is, address "B" is registered in the transfer database 12a (step A4).

In this example, as shown in FIG. 2(A), addresses "A" and "Bo" are registered in the transfer database 12a, so the boat number corresponding to the destination address "B" is It is determined that the port numbers that received the input data are the same (step A6), and the destination address "
It is recognized that "B" is connected to the same port P1 as the source address "A". In this case, there is no need to transfer the packet data to another port P2, so the received packet is discarded. (Step A7).

Next, consider a case where the terminal device 4 with the address “A” sends a data packet to the terminal device B with the address “C”. In this case, the terminal device 4 with the address “A” mentioned above sends a data packet to the terminal device B with the address “B”. In the same manner as the processing when sending the data packet to the device 5, steps At, A3. A
However, in step A4, it is recognized that the address "C#" is not registered in the transfer database 12a, and the data is transferred to a boat other than boat P1, that is, boat P2 (step A5).

Next, the terminal device 7 with the address “D” receives the address “Bo”.
Consider the case where a data packet is sent to the terminal device 5 of . In this case, since the data packet from the terminal device 7 is input to the bridge device 11 via the second input port P2, it is determined that data has been received at the input port P2 (step AI). When data is received at the input port P2, the second transfer database 12b corresponding to the input port P2 is searched (step A2), and the destination address of the input data, that is, address "B" is registered in the transfer database 12b. It is determined whether or not (step A4). In this example, as shown in FIG. 2(B), the transfer database 12b has the address "
Since "B" is not registered, the data is transferred to a port other than boat P2, that is, port PL (step A5).
).

In this way, in this embodiment, the transfer database is divided and constructed for each input port, and only the address B of the database corresponding to the input port that received the data is searched. Therefore, the average address search time can be reduced to about half compared to the conventional method, and sufficient data transfer efficiency can be obtained even in a network system with a large number of terminals.

Next, a transfer database 12a suitable for this embodiment,
The management process of 12b will be explained with reference to the flowchart of FIG.

First, it is determined whether the port that received the data packet is Pl (step Bl), and the input port P1
When a data packet is received in the first transfer database 12a, the source address SA of the data packet (for example, in the case of a data packet from the terminal device 4 with address 'A', corresponding to address 'A') is stored in the first transfer database 12a. information)
is registered (step B2).
). If it is registered, the timer value corresponding to the source address is refreshed (step B3).
). In addition, if the source address SA is the forwarding database 12
If the source address SA is not registered in the transfer database 12a, the sender address SA is newly registered in the transfer database 12a (step B4).
). In this case, it is assumed that the terminal device with the source address SA was relocated from the port P2 and connected to the port PI, so the transfer database 12b is also searched for the source address SA (step B5). , if the address is registered, information regarding that address is deleted from the transfer database 12b (step Be).

Even when the port that received the data packet is P2, the database 12b is managed in the same way through the processes from step 87 to Bll.

Note that although we have only explained an example in which the forwarding database is divided into two parts corresponding to two ports, it is also possible to construct a forwarding database by dividing the forwarding database for each port in a multiport bridge device that has three or more ports. , the average address search time can be shortened.

〔Effect of the invention〕

As described above, according to the present invention, sufficient data transfer efficiency can be obtained even in a network system with a large number of connected terminals.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a bridge device according to an embodiment of the present invention, FIG. 2 is a diagram showing the contents of first and second transfer databases provided in the bridge device shown in FIG. 1, FIG. 3 is a flowchart explaining the data transfer operation of the bridge device shown in FIG. 1, and FIG.
A flowchart explaining the management operation of the transfer database by the multiport bridge device shown in the figure, FIG. 5 is a block diagram showing the conventional bridge device, and FIG. 6 shows the contents of the transfer database provided in the conventional bridge device. FIG. 2.3... LAN, 4-7... terminal device, 11...
- Bridge device, 12a, 12b--Transfer database, Pl. P2...Input port. Figure 1 (A)

Claims (1)

[Claims] first and second input ports each connected to a corresponding network; a first database storage means in which address information of a terminal corresponding to the first input port is registered; a second database storage means in which the address information of the corresponding terminal is registered; and one of the first and second database storage means according to the input port from which the data is received when data is received from the network. 1. A bridge device comprising: control means for selecting either one and controlling data transfer by referring to address information registered in the selected database storage means.