JPH04245741A - Repeating system for bridge - Google Patents

Abstract

PURPOSE:To prevent the rise of traffic and to remove overhead causing the cancel of a useless frame in a station by inhibiting the repeat of an unnecessary broadcasting frame in a bridge between two networks or more. CONSTITUTION:A frame received from a transmission line 2a is inputted to a bridge repeating processing part 11 through a receiving part 13a. The processing part 11 interpretes an MAC address in the frame and unconditionally sends frames other than a broadcasting frame to a transmission line 2b through a transmitting part 12b. In the case of the broadcasting frame, whether the frame is to be repeated or not is decided in accordance with a previously specified mode, the broadcasting frame in the repeating mode is sent to the transmission line 2b similarly to other frames and the broadcasting frame in the nonrepeating mode is canceled without being repeated.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bridge relay system, and more particularly to a broadcast relay system.

0002

2. Description of the Related Art Conventionally, this type of bridge has had means for unconditionally relaying broadcast frames.

0003

[Problems to be Solved by the Invention] The conventional bridges described above unconditionally relay broadcast frames, so they relay broadcast frames even to networks that do not need to be relayed, causing an unnecessary increase in traffic. The disadvantage is that useless broadcast frames must be received and discarded.

[0004] An object of the present invention is to prevent the generation of unnecessary traffic by intentionally not relaying broadcast frames to unnecessary networks in the bridge, thereby reducing the increase in traffic and wasteful broadcast frames at stations. The purpose is to solve the problem of having to dispose of it.

[0005]

[Means for Solving the Problems] The bridge relay method of the present invention determines whether or not to relay a broadcast frame whose MAC address is a broadcast frame in a bridge that relays between two or more networks. means for preselecting a mode in advance, means for unconditionally bridge-relaying frames other than the broadcast frame, and means for bridge-relaying the broadcast frame in the mode of relaying broadcast frames and in the mode of not relaying the broadcast frames; It has means for not relaying frames by the bridge, and means for enabling the mode to be set for each bridge node.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a diagram illustrating the functions of an embodiment of the present invention, and FIG. 2 is a block diagram of a bridge according to an embodiment of the present invention. To simplify the explanation, a bridge that relays two networks will be described, but the same applies when connecting three or more networks. Further, the transmission path access method may be any of the CSMA/CD method, the token bus method, or the token ring method.

FIG. 1(a) is a diagram illustrating the functions when used in the broadcast relay mode. In this case, the broadcast frame sent from the station 3a to the transmission path 2a passes through the bridge 1 unconditionally and is sent to the transmission path 2b of another network. Further, other stations connected to the transmission path 2a will also receive the broadcast frame.

FIG. 1(b) is a diagram illustrating functions when used in a mode in which broadcasts are not relayed. In this case, the broadcast frame sent from the station 3a is sent to the transmission path 2a, but the transmission path 2b side of the bridge 1 is in a mode that does not relay broadcasts, so the broadcast frame is not sent to the transmission path 2b. . Therefore, station 3b connected to transmission path 2b also does not receive the broadcast frame. Even if broadcast frames are relayed, if the network on transmission path 2b does not use broadcast frames, broadcast frames are unnecessary frames, and since all stations will always receive them, stations that do not need broadcast must discard the frame each time it is received. Therefore, by not allowing unnecessary broadcast frames to pass through the bridge, the traffic on the transmission path can be reduced, and the overhead of discarding unnecessary broadcast frames at the station can be reduced.

Next, the operation of the bridge 1 will be explained in detail.

[0011] The frame received from the transmission path 2a is 13a.
It is received by the bridge relay processing unit 11 and passed to the bridge relay processing unit 11. In the bridge relay processing section 11, among the received frames, frames other than broadcast frames are unconditionally sent to the transmitting section 12b, and sent out to the transmission path 2b. In the case of a broadcast frame, it is relayed in the same way as other frames, like a normal bridge, depending on the pre-specified broadcast relay mode. In the case of non-relay mode, the broadcast is not relayed and is discarded. Further, the relay from the transmission path 2b to the transmission path 2a uses the receiving section 13b and the transmitting section 12a. Note that even when three or more transmission lines are connected, the broadcast relay mode can be set for each port, and it is possible to select whether or not to relay the broadcast depending on each mode.

[0012] If there is even one station that must receive broadcasts, it must be set to a mode that relays broadcasts. In order to effectively use the bridge of the present invention, it is necessary to separate networks into applications that use broadcasting and applications that do not use broadcasting.

FIG. 3 shows an example of a network address system. In any of the CSMA/CD networks, token bus networks, and token ring networks, the MAC address often uses the I/G bit to distinguish individual addresses from broadcast addresses. In this case, if the I/G bit is "0", it is an individual address, if the I/G bit is "1", it is a group broadcast, and if the address is all "1", it is defined as a broadcast address. ing. Therefore, in the bridge relay processing unit 11, all MAC addresses are "1".
You can tell whether it is a broadcast by determining whether it is a broadcast or not.

[0014]

As explained above, the present invention prevents unnecessary traffic by having a means for not relaying unnecessary broadcast frames, thereby reducing the overhead of increasing traffic and discarding useless broadcast frames at stations. It has the effect of eliminating

[Brief explanation of the drawing]

FIG. 1 is a diagram illustrating the functions of an embodiment of the present invention.

FIG. 2 is a block diagram of a bridge according to an embodiment of the present invention.

FIG. 3 is an example of a MAC address system.

[Explanation of symbols]

1 Bridge 2a, 2b Transmission line 3a, 3b Station 11 Bridge relay processing section 12a, 12b Transmission section 13a, 13b Receiving section

Claims (1)

[Claims] 1. In a bridge that relays between two or more networks, means for preselecting a mode of whether or not to relay a broadcast frame whose MAC address is broadcast by the bridge; means for unconditionally bridge-relaying the frame, means for bridge-relaying the broadcast frame in the case of a broadcast frame relay mode, and means for not bridge-relaying the broadcast frame in the non-relay mode; 1. A bridge relay method characterized by comprising means for enabling settings for each node.