JPH05136785A - Fault packet prevention device - Google Patents

Abstract

PURPOSE:To enhance the system operating efficiency of a local area network. CONSTITUTION:A packet reception section 20 always receives a packet sent to a network during the operation of the network, a fault packet detection section 21 collates the packet of a fault pattern set in advance with a reception packet and in the case of a packet of a fault pattern, a packet transmission section is accessed to cause the collision of packets by intention, then the packet is invalidated and in the case of fault detection, a display section 23 implements the display informing the occurrence of the fault packet thereby informing the occurrence of the fault packet to the operator. Thus, as to the transmission of a tentative fault packet, the fault packet is automatically invalidated to prevent frequent stop for the system thereby enhancing the operating efficiency.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an abnormal packet prevention apparatus for preventing a network failure due to an abnormal packet generated on a local area network (LAN).

[0002]

2. Description of the Related Art Generally, in a CSMA / CD type local area network, a packet transmitted from a certain terminal is transmitted to all terminals of the network connected only at a data link layer or lower. Therefore, when an abnormal packet having a condition that causes an abnormality in the network is transmitted from a certain terminal, for example, the broadcast address (BC) of the packet is set to all 1s or all 0s as a system. However, if the BC of the packet transmitted for some reason contains the opposite data, or if the source address indicating the source of the packet is contained in the broadcast address (BC) However, there is a risk that an abnormal increase in traffic in the network (broadcast storm) or network outage may occur.

[0003]

However, in the conventional local area network, no measures have been taken in advance to prevent a failure due to such an abnormal packet from occurring, and when an abnormal packet occurs, However, even if it is a transient abnormality, the network function must be stopped, the cause must be investigated, and the system must be restarted, which causes a problem of impairing system operation efficiency.

The present invention has been made in view of such conventional problems. When an abnormal packet that causes an abnormality in the network is transmitted from any terminal, the abnormal packet is detected and temporarily sent. It is an object of the present invention to provide an abnormal packet prevention apparatus that prevents an abnormal occurrence of a network by invalidating an abnormal packet by intentionally causing a physical failure.

[0005]

SUMMARY OF THE INVENTION An abnormal packet prevention apparatus according to the present invention is a packet receiving unit for receiving a packet transmitted on a network, a packet transmitting unit for transmitting a packet to the network, and the packet receiving unit. The packet received by the unit is compared with the preset abnormal pattern packet, and when the packet has the abnormal pattern, the packet transmission unit is accessed and the packet is intentionally caused to collide, thereby invalidating the packet. The packet detector includes a packet detector and a display for displaying an abnormal packet occurrence when the abnormal packet detector detects an abnormal packet.

[0006]

In the abnormal packet prevention apparatus of the present invention, during operation of the network, the packet receiving section always receives the packet transmitted to the network, and the abnormal packet detecting section receives the packet having the abnormal pattern set and the received packet. When the packet has an abnormal pattern, the packet transmitter is accessed to invalidate the packet by intentionally causing a packet collision. Is displayed to notify the operator of the occurrence of an abnormal packet.

In this way, the abnormal packet is automatically invalidated in response to the temporary abnormal packet transmission, so that frequent stoppage of the system is prevented and the operation efficiency is improved.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 shows a system configuration of a local area network in which a plurality of terminals a, b, c, ... Are connected to a transmission line 1, and an abnormal packet prevention device 2 according to an embodiment of the present invention. Is also connected. Between the terminals a, b, c, ... CSMA / C as shown in FIG.
The packets P of the D method are transmitted to each other.

The packet P is composed of a broadcast address BC indicating a transmission destination, a source address A indicating a transmission source, and transmission data Data.

The abnormal packet prevention device 2 is connected to the transmission line 1 as shown in FIG. 3, and receives a packet transmitted to the transmission line 1 and a packet reception unit 20 which receives the packet. An abnormal packet detection unit 21 that detects an abnormal packet by checking the abnormal packet condition set in advance for the packet and intentionally causes an abnormality such as a short circuit, an open, or a packet collision when the abnormal packet is detected. It is composed of a failure occurrence unit 22 and a display unit 23 that displays the content of the data, the type of abnormality, etc. when an abnormal packet is detected.

The abnormal packet condition preset in the abnormal packet detector 21 is usually all 1
Alternatively, a method of determining whether the broadcast address set to all 0 is the opposite data to that setting, or a method of determining whether the source address A is not the broadcast address BC is used. Be done.

Further, the fault generating section 22 causes a fault by a method of causing a packet collision by generating the same packet as the received packet or a method of directly generating a collision signal.

Next, the operation of the abnormal packet prevention device having the above configuration will be described.

In normal operation, a terminal sends out a packet having the data structure shown in FIG. 2 to a transmission path, and a terminal at the end receives the packet, judges the contents of its broadcast address, and determines its own address. If it is an address, the packet is received, and if it is not its own address, it is ignored.

In this transmission operation, the abnormal packet prevention device 2 constantly monitors the packets transmitted to the transmission line 1, and the packet receiving unit 20 receives all the packets and the abnormal packet detecting unit 21 receives them one by one. give.

The abnormal packet detector 21 collates a given packet with preset abnormal packet conditions, and if the packet is not an abnormal packet, no operation is performed, but a packet matching the abnormal packet condition is detected. If so, an abnormal packet detection signal is given to the failure occurrence unit 22 and the display unit 23.

Therefore, the failure generating unit 22 sends the same packet causing the packet collision to the transmission line 1 before the abnormal packet ends, or sends the packet collision signal to the transmission line 1.

As a result, when the local area network side detects this packet collision or receives the collision signal, all the terminals a, b, c, ... Will ignore the abnormal packets that have been received until then. As a result, the system is not stopped due to the abnormal packet, and the continuous operation of the system is possible.

When the abnormal packet is generated, the contents of the abnormal packet are displayed on the display unit 23 or the abnormal packet is detected and displayed so that the operator can be notified of the occurrence of the abnormal packet.

In this way, the abnormal packet is monitored,
When it detects it, it actually causes a packet collision,
Alternatively, by generating a collision signal, it is possible to prevent each terminal from receiving an abnormal packet and to prevent the system from being stopped due to the abnormal packet.

[0022]

As described above, according to the present invention, when an abnormal packet is transmitted, the abnormal packet is detected and a signal for causing packet collision is automatically sent to the transmission line. Since each terminal does not receive the abnormal packet in this way, it is possible to prevent the occurrence of a long-term and difficult-to-recovery abnormality of the network due to the abnormal packet, and improve the operation efficiency of the system. ..

[Brief description of drawings]

FIG. 1 is a system configuration diagram of a local area network used in an embodiment of the present invention.

FIG. 2 is a data configuration diagram of a packet used in the above embodiment.

FIG. 3 is a functional block diagram of the abnormal packet prevention device of the above embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transmission line 2 Abnormal packet prevention device 20 Packet receiving unit 21 Abnormal packet detection unit 22 Failure occurrence unit 23 Display unit a, b, c, ... Terminal BC Broadcast address A Source address Data data

Claims (1)

[Claims] 1. A packet receiving unit for receiving a packet transmitted on a network, a packet transmitting unit for transmitting a packet to the network, and a packet preset by the packet receiving unit for receiving an error. An abnormal packet detection unit that collates with a packet of a pattern, accesses the packet transmission unit when the packet is an abnormal pattern, and invalidates the packet by intentionally causing a packet collision; An abnormal packet prevention device comprising: a display unit for displaying a notification of the occurrence of an abnormal packet when an error is detected.