JPH0870319A - Packet processing system in lan bridge system - Google Patents

Abstract

PURPOSE: To obtain a packet processing system in an LAN bridge system capable of preventing the decline of throughput even when many LANs are connected and housed. CONSTITUTION: Packets transmitted from LAN housing parts 13 and 23 to a system bus 30 are stored in the reception parts 16 and 26 of the respective LAN housing parts 13 and 23 without being stored in a CAM controller 32. In the middle of storing the data of the packets, the destination address(DA) and source address(SA) of packet data are extracted by the CAM controller 32 and filtering and routing are executed. Thus, the overlapping of transfer that the packets transmitted from the LAN housing parts 13 and 23 to the system bus 30 are tentatively stored and then transmitted to the system bus 30 again is eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention accommodates a plurality of LANs (local area networks) for connecting terminals having unique addresses and bridges these LANs via a system bus. The present invention relates to a packet processing method in a LAN bridge system that uses packets for data transmission / reception, and particularly to a packet processing method in a LAN bridge system that prevents a decrease in system bus throughput.

[0002]

2. Description of the Related Art Conventionally, in a packet processing method in this type of LAN bridge system, an arbiter 51 and a frame filter section 52 are applied to a packet transmitted from a LAN 10, 20 to a system bus 50, as shown in FIG. , The buffer 53, and the database 54 perform a frame filtering function.

Here, the configuration on the LAN side will be described. As shown in FIG. 3, terminals 11 to 12 and 21 to 22 and LAN accommodating portions 61 and 62 are connected to the LANs 10 and 20, respectively. LAN accommodating parts 61 and 6
2 includes interface units 63 and 64 and transmission units 65 and 6.
6, and receivers 67 and 68 are provided, and a transmitter 65,
66 and receivers 67 and 68 are connected to a system bus 50 that bridges between the LANs 10 and 20. The arbiter 51 connected to the transmission units 65 and 66 is also connected to the frame filter unit 52, determines the transmission right of the system bus 50, and notifies the transmission units 65 and 66 or the frame filter unit 52.

The functional operation of packet processing will be described below with reference to FIG.

Interface section 63 of LAN accommodating section 61
Receives all of the packets on the LAN 10 it accommodates,
It is sent to the transmitter 65. The transmission unit 65 requests the arbiter 51 for transmission, obtains the transmission right of the system bus 50, and sends the received packet to the frame filter unit 52 via the system bus 50.

The frame filter unit 52 temporarily stores the packet received from the system bus 50 in the buffer 53. The frame filter unit 52 collates the destination address (DA) of the stored packet with the database 54 for filtering, and performs a filtering function of determining the destination LAN of the packet. Further, if the source address (SA) of the packet stored in the buffer 53 does not exist in the database 54, the frame filter unit 52 stores the source address (SA) in the database 54.
Register with.

Further, the frame filter section 52 has a frame routing function. That is, when the frame filter unit 52 determines that the stored packet should not be transferred to another LAN storage unit 62, it discards this packet. On the other hand, when the frame filter unit 52 determines that the stored packet should be transferred to another LAN storage unit 62, the frame filter unit 52 obtains the transmission right of the system bus 50 from the arbiter 51 and transmits this packet to the system bus. It is sent to the LAN accommodating portion 62 via 50. The LAN accommodating section 62 receives this packet at the receiving section 68 and sends it to the LAN 20 via the interface section 64.

[0008]

DISCLOSURE OF THE INVENTION The conventional LAN described above
In the packet processing method in the bridge system, the frame filter unit receives and stores all the transmission data generated in the LAN via the system bus, and centrally processes the filtering function and the routing function. With this configuration, when a large number of LANs are accommodated and connected, all the packet frames from each LAN are concentrated on the frame filter unit via one system bus. As a result, there is a problem in that the amount of processing in the frame filter unit becomes enormous and the throughput is reduced.

An object of the present invention is to provide a LAN bridge system capable of preventing a decrease in throughput on a system bus by removing some functions from a frame filter section, which is a centralized processing section of functions, and distributing them to each LAN accommodating section. To provide a packet processing method.

[0010]

A packet processing method in a LAN bridge system according to the present invention accommodates a plurality of LANs (local area networks) connecting terminals having unique addresses, and connects the LANs via a system bus. In a packet processing method in a LAN bridge system in which a packet is used for data transmission / reception on the system bus, the destination address (D
A) A destination address (DA) and a source address (SA) are extracted from the associative memory device (CAM) for filtering the source address (SA) and the packet data transferred on the bus system, and extracted. A CAM control device that registers the destination address (DA) and the source address (SA) that have been registered, filters them by the associative memory device (CAM), and outputs a notification of the discard / relay of the transferred packet data. And transmitting the packet data to the system bus while accommodating the LAN, receiving and storing all the packet data transferred on the system bus, and issuing the discard / relay notification of the received and stored packet data to the CAM. And a LAN accommodating portion received from the control device.

Further, the CAM control device includes a transmission monitoring unit for monitoring packet data transferred on the system bus, and a DA for extracting a destination address (DA) from the packet data transferred on the system bus. An extraction unit, an SA extraction unit for extracting a source address (SA) from the packet data transferred on the system bus, and an absence information of the packet data transferred on the system bus from the transmission monitoring unit, Source address (SA)
SA storage unit for instructing the data registration of the data, the destination address (D) extracted from the DA extraction unit and the SA extraction unit.
A) The associative storage device (CAM) for filtering the source address (SA) and the associative memory (CAM) with the destination address (DA) and the source address (SA) extracted from the DA extraction unit and the SA extraction unit. Storage device (CA
An access control unit for controlling the filtering of M) and for registering a source address (SA) in the associative storage device (CAM) according to an instruction from the SA storage unit;
A discard / relay determination unit that receives the result of filtering from the associative memory device (CAM) and notifies the LAN accommodating unit whether to discard or relay the packet data fetched from the system bus; and the associative memory device (CAM). If the source address (SA) is registered in the associative memory (CAM), it is determined that the source address (SA) is not registered. The SA storage unit includes a learning determination unit that requests registration of the source address (SA).

[0012]

Next, the present invention will be described with reference to the drawings.

FIG. 1 is a functional block diagram showing an embodiment of the present invention. In the packet processing method in the LAN bridge system shown in FIG.
M controller 32 is connected, and associative memory (CAM) 33 is connected to CAM controller 32.
In addition to the arbiter 31, the M control device 32 includes each LAN.
The configuration differs from the configuration in FIG. 3 in that the receiving units 16 and 26 of the accommodating units 13 and 23 are connected. Furthermore, the LAN accommodation unit 1
This is different from the configuration of FIG. 3 in that the receiving units 16 and 26 of 3 and 23 receive and store all of the packet data on the system bus 30.

In FIG. 1, terminals 11-12, 21-
LANs 10 and 20 housing 22 are LAN housing units 13,
It is connected to one system bus 30 via 23. The LAN accommodating units 13 and 23 are the interface unit 1
4, 24, transmitters 15 and 25, and receivers 16 and 26.
have. Via the interface units 14 and 24,
The transmitters 15 and 25 and the receivers 16 and 26 are the LAN 1
It is connected to 0 and 20. On the other hand, the transmitters 15 and 25 are connected to the system bus 30 and the arbiter 31. The receiving units 16 and 26 are the system bus 30 and the CAM.
It is connected to the control device 32.

The arbiter 31 includes transmitters 15, 25 and C.
It is connected to the AM control device 32 and gives the transmission units 15 and 25 the right to transmit the system bus 30. The CAM control device 32 is connected to the associative storage device (CAM) 33 together with the system bus 30, and as described above, the receiving unit 1
6, 26, and the arbiter 31. CAM
The control device 32 serves as a packet processing unit that monitors the state of the arbiter 31 and processes a predetermined functional operation while the packet is being transferred on the system bus 30.

That is, the CAM control device 32 takes in the packet data on the system bus 30, filters the destination address (DA) and the source address (SA) through the associative storage device (CAM) 33, and Discarding / relaying the target packet is determined from the result of filtering the destination address (DA), and the determination result is notified to the LAN accommodating units 13 and 23. On the other hand, the CAM control device 32
When address learning is required from the result of filtering the source address (SA), the address data is registered in the associative storage device 33.

Each of the LAN accommodating units 13 and 23 receives the discarding / relaying instruction from the CAM control device 32 at the receiving units 16 and 26, and in accordance with the discarding / relaying instruction, the receiving unit 1
The packets received from the system bus 30 at 6 and 26 are discarded or relayed, and the interface units 14 and 24
To the LANs 10 and 20 via.

Next, a configuration example of the CAM control device 32 of FIG. 1 will be described with reference to FIG. 2 is the CA of FIG.
It is a functional block diagram which shows a detailed Example of the M control apparatus 32. The illustrated CAM control device 32 includes a transmission monitoring unit 41, a DA extraction unit 42, an SA extraction unit 43, and an SA storage unit 4.
4, an access control unit 45, a discard / relay determination unit 46, and a learning determination unit 47.

The transmission monitoring unit 41 is connected to the system bus 30 and the arbiter 31, and monitors the arbiter 31 to detect L level.
It recognizes the packet transmission states of the AN accommodating units 13 and 23 and controls the operation in the CAM control device 32. The DA extraction unit 42 extracts the destination address (DA) from the packet on the system bus 30, and the SA extraction unit 43 extracts the source address (S) from the packet on the system bus 30.
Extract A). The extracted destination address (DA) and source address (SA) are notified to the access control unit 45 and used as a filtering instruction. As a result, the access control unit 45 uses the associative storage device (CAM) 33 to specify the destination address (DA) and the source address (SA).
Handle the filtering function for.

The associative storage device (CAM) 33 notifies the discard / relay determination unit 46 of the result of filtering the destination address (DA), and the discard / relay determination unit 46 determines whether the packet is discarded or relayed. Each LAN accommodation unit 13,
Notification is made every 23rd. For example, in the case of an incoming packet to the LAN accommodating unit 13, the filtering result is LAN
The storage section 13 is instructed to relay, and the LAN storage section 2
For 3, the instruction for disposal is given.

The result of the filtering of the source address (SA) is notified to the learning judgment unit 47 by the associative storage device (CAM) 33. When the learning determination unit 47 determines that the address data is required to be registered, the learning determination unit 47 generates an address learning signal and notifies the SA storage unit 44 of it. Upon receiving the address learning signal, the SA storage unit 44 extracts the source address (SA) from the SA extraction unit 43, and when receiving the notification of the packet transmission end on the system bus 30 from the transmission monitoring unit 41, the access control unit 45 associative memory (CAM) 3
Register the address data in 3.

In the above description, two LANs are shown and described, but a bridge system in which a larger number of LANs are bridged by one system bus is practical. Further, the functional blocks shown in the drawings are examples, and another block configuration that is divided or merged may be used as long as it has the function of the above description, and the above description does not limit the present invention. Absent.

[0023]

As described above, according to the present invention, L
Packets transmitted from the AN accommodation unit to the system bus are
Instead of being stored in the CAM control device which is the packet processing means, it is stored in the receiving section of each LAN storage section, and while the data of this packet is being stored, the destination address (DA) of the packet data and the transmission Original address (SA)
Are extracted and filtering and routing are performed. This configuration eliminates the duplication of transfer in which the packet transmitted from the LAN accommodating unit to the system bus is once stored and then transmitted to the system bus again. As a result, it is possible to obtain a packet processing method in a LAN bridge system that can prevent a decrease in throughput even if many LANs are connected and accommodated.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing an embodiment of the present invention.

FIG. 2 is a functional block diagram showing an example of partial details of FIG.

FIG. 3 is a functional block diagram showing a conventional example.

[Explanation of symbols]

 10, 20 LAN (Local Area Network) 11-12, 21-22 Terminal 13, 23 LAN accommodation section 14, 24 Interface section 15, 25 Transmission section 16, 26 Reception section 30 System bus 31 Arbiter 32 CAM control apparatus 33 Associative memory Device (CAM) 41 Transmission monitoring unit 42 DA extraction unit 43 SA extraction unit 44 SA storage unit 45 Access control unit 46 Discard / relay determination unit 47 Learning determination unit

Claims (3)

[Claims] 1. A plurality of LANs (local area networks) for connecting terminals having unique addresses are accommodated,
Bridge between the LAN via the system bus,
In a packet processing method in a LAN bridge system that uses packets for data transmission / reception on the system bus, the LAN is accommodated and packet data is transmitted to the system bus, while all packet data transferred on the system bus is received. The LAN accommodating unit for storing and the destination address (DA) and the source address (SA) are extracted from the transferred packet data, and the extracted destination address (DA) and source address (S) are extracted.
The filtering of A) is performed, and the result of discarding / relaying of the packet data received / stored is notified by the LA.
A packet processing method in a LAN bridge system, comprising: a packet processing means for notifying the N accommodation unit. 2. A plurality of LANs (local area networks) for connecting terminals having unique addresses are accommodated,
Bridge between the LAN via the system bus,
In a packet processing method in a LAN bridge system that uses packets for sending and receiving data on the system bus, a destination address (DA) and a source address (S
Associative memory (CAM) for filtering A)
And the destination address (DA) and source address (SA) from the packet data transferred on the bus system.
And the extracted destination address (DA) and source address (SA) are registered with the data and filtered by the associative storage device (CAM).
A CAM control device that outputs a notification of discard / relay of the transferred packet data and the LAN, and transmits the packet data to the system bus, while receiving and storing all the packet data transferred on the system bus. And a LAN accommodating unit that receives a notification of discard / relay of the packet data received and stored from the CAM control device, the packet processing method in the LAN bridge system. 3. The CAM control device according to claim 2, wherein the CAM control device monitors a packet data transferred on the system bus, and a destination address (DA) based on the packet data transferred on the system bus. ) For extracting the source address (SA) from the packet data transferred on the system bus.
An extraction unit, an SA storage unit that receives absence information of packet data transferred on the system bus from the transmission monitoring unit, and instructs data registration of a source address (SA), the DA extraction unit and the SA extraction An associative storage device (CAM) that filters a destination address (DA) and a source address (SA) extracted from a unit, a destination address (DA) extracted from the DA extraction unit and the SA extraction unit, and The filtering of the content addressable memory (CAM) is controlled by the source address (SA), and the source address (SA) is controlled by the instruction from the SA storage unit.
An access control unit for registering data in the associative memory device (CAM) with the LAN accommodating unit, which receives a filtering result from the associative memory device (CAM) and discards or relays the packet data taken from the system bus. To the discard / relay determination unit for notifying the user and the filtering result from the associative storage device (CAM),
It is determined whether the source address (SA) is registered in M), and if it is determined that the source address (SA) is not registered as a result, the source address (SA) of the source address (SA) is stored in the SA storage unit. A packet processing method in a LAN bridge system, comprising: a learning determination unit for requesting registration.