JPH024071A - Packet communication device - Google Patents

Abstract

PURPOSE:To dispense with a processing related to the change of a header part and to decrease the load of an arithmetic processing unit by copying the header part added to a packet and transferring the packet having the copied header part. CONSTITUTION:When the packet is received from a communicating device at the time of judging the fact that a loop back transfer control part 17 is in a high load condition, a header copying part 15 and a packet sending preparing part 13 are operated, and a loop back transfer control is executed. By the header copying part 15, the header part added to the packet from the communicating device is copied, and it is sent to the packet sending preparing part 13. By the packet sending preparing part 13, the header part copied by the header copying part 15 is added to a message for controlling, a packet for controlling is prepared, and the packet for controlling is transmitted through a transmission line L31 to the communicating device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a packet communication device that is one type of digital data exchange (DDX) that transmits data digitally.

(Prior art) Conventionally, when transmitting data digitally, this digital data is divided into pieces of predetermined length, and a header having an address etc. is added to each divided message to form a packet. A communication method has been proposed in which data is transmitted in units of .

Such a conventional communication method is shown in FIG. 5 as a device 101.
lines 107 and 109 between each of 103.105
This will be explained using an example where . Devices 101, 10
As shown in FIG. 6, a packet 111 transmitted between 3 and 105 is composed of a message section 113 and a header section 115 containing a destination address and the like.

Here, when data h consisting of packets from devices 101 and 105 (concentrates on device 103 and enters a so-called high load state or overload state), device 103 performs control to alleviate such concentration of packets.

For example, when the device 103 is in a high load state, the device J, 1
Upon receiving the packet from 01, it transmits a control packet to the device 101 to temporarily suspend and clear the transmission of the current packet. At this time, it becomes necessary for the device 103 to remove information regarding the destination of the control packet, that is, the header.

Therefore, the Hi2ff 103 transmits the source information included in the received packet or the information regarding the channel number (LCN) set corresponding to the line 107 included in the header part to W? When the packet is read and it is determined that the sender of this packet is the device 101, a header section indicating that the device 101 is the destination is added to the packet and transmitted.

(Problem to be Solved by the Invention) However, when transmitting control packets as described above, in addition to decoding the received packets,
It was necessary to replace the so-called header section, which was a complicated process and took time.

Furthermore, in order to decode the source information included in the packet mentioned above or the information regarding the channel number in the header section, it is necessary to drive an arithmetic processing section such as a microcomputer, and it is possible to reduce the negative 1u of the arithmetic processing section. It was wanted.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a packet communication device that can reduce the burden on the arithmetic processing unit and can quickly transmit control packets and the like.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a system in which the line from one device to the other device and the line from the other device to the one device are the same. Replication that copies a header added to a received packet in a packet communication device that communicates via a transmission path set to a channel number using a packet formed of a header including the channel number and a message. and a transmitting means for transmitting the packet to which the header part copied by the copying means has been added to the source of the received packet.

(Function) In the packet communication device of the present invention, a line going from one device to another device and a line going in the opposite direction, that is, from the other device to one device, are transmitted through a transmission path set to the same channel number. packets are transmitted. This packet is formed of a header section including the channel number and a message section. Furthermore, when the other device receives a packet from one device, it has a copying means for copying the header added to this packet, and the packet with the header added copied by the copying means is sent to the sender. In other words, the message is sent to one of the devices, eliminating the need for processing for replacing the so-called header section.

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

First, the connection configuration of this embodiment will be explained with reference to FIG.

A plurality of communication devices 1, 3, and 5 consisting of exchanges, etc. are installed, and the communication devices 1 and 3 and the communication devices 3 and 5 are connected through corresponding transmission paths, and communication is performed in units of packets. will be carried out.

Specifically, there is an uplink that transmits packets from the communication device 1 to the communication device 3 via the transmission path LI3, and an uplink that transmits packets from the communication device @3 to the communication device 1 via the transmission path 31. are set to the same channel number. Similarly, packets from communication device 3 are transferred to transmission path L.
35 to the communication device 5, and packets from the communication device 5 to the communication device 3 via the transmission path L53.
The same channel number is set for the downlink to be transmitted to. The above-mentioned packet is formed of a header part as destination information including such a channel number, and a message part having data information.

Next, with reference to FIG. 1, communication device 3 will be explained as a representative among the plurality of communication devices.

The packet receiving unit 11 is connected to the transmission line LI3 and receives packets from the communication device 1. When the packet received by the packet receiving section 11 is a packet to be transmitted to the transmission path L31, it is output to the packet transmission generating section 13 via a packet switch section (not shown). This packet switch section performs control for receiving and passing packets from the bucket 1 to the receiving section 11 to the target line by, for example, a contention control method using a bus.

The header copy portion 15 is connected to the packet receiving section 11 via a signal line 21, and receives packets from the packet receiving section 11. The header copy section 15 is a copying means for copying the header added to the input packet. The header section 15 includes a plurality of signals FA
It is connected to the return transfer control section 17 via 23, and performs the above-described copying operation based on control commands from the return transfer control section 17. Furthermore, the Hetsudacobi part 15 is connected to the packet transmission generation section 13 via a plurality of signal lines 25, and outputs information regarding the duplicated header section to the packet transmission generation section 13.

Next, an example of the internal configuration of the header copy portion 15 will be described with reference to FIG.

The header section is made up of a plurality of bits, and the number of D-type flip-flop O7 circuits 31 corresponds to the number of bits.
a, 3 lb, -31n are directly connected to '+14. The input terminal of the first-stage flip-flop circuit 3a is connected to a signal line 21, and receives a packet output as serial data from the packet receiving section 11.

One input terminal of the AND circuit 33 is connected to the return transfer control unit 17 via the signal Fl+23a, and corresponds to a pill signal forming a header portion of a packet formed of a plurality of bit signals, for example. Only for a period ゛H''
Input the level signal.

The other input terminal of the AND circuit 33 is connected to the return transfer control section 17 via a signal line 23b, and receives a bit clock synchronized with each bit signal of the header section formed by a plurality of bit signals. The output terminals of the AND circuit 33 are flip-flop circuits 31a, 31b, .
...31n is connected to each clock input terminal, and the logical product output of the AND circuit 33 is used as the clock signal 33
a as flip-flop circuits 31a, 31b, .
...Give to each clock input terminal of 31n.

Therefore, the multi-bit signal forming a packet as serial data input via the signal line 21 is sequentially transmitted from the flip-flop circuit 31a to the flip-flop circuit 31b in synchronization with the output timing of the clock signal 33a for each 1-bit signal. .

... is shifted to 31n.

Noritsubu flop circuits 31a, 31b,...31
Each output terminal Q of n is connected to a corresponding signal line 25a,
25b, . . . , the packet transmission generation unit 13 via 25n.
It converts the signal in the header section as serial data into parallel data, copies it, and outputs it to the packet transmission generation section 13.

Referring again to FIG. 1, the return transfer control unit 17 has monitoring means for monitoring the load state of the communication device 3, and when the load state is high, for example, packets from other communication devices 1 are When data is transmitted to the communication device 3 in a concentrated manner, return transfer control is executed to alleviate this high load state.

The packet transmission generating section 13 has a generating means for generating a control message, for example, a message to temporarily suspend the transmission of the current packet and clear the message. The packet transmission generation section 13 is connected to the return transfer control section 17, and based on a control command from the return transfer control section 17, sends out a packet having a control message. That is, after converting the copied header part from the header copy part 15 into serial data, this header part is added to the aforementioned control message to generate a control packet, and this control packet is sent to the transmission line. Transmit via L3.

At this time, the return transfer control unit 17 may control so that control packets with the same content are not transmitted to the same communication device 1 in duplicate.

Note that the communication devices 1 and 5 similarly have the device configuration shown in FIG. 1, and detailed description thereof will be omitted.

Next, the operation will be explained.

When the return transfer control unit 17 determines that it is in a high load state and receives a packet from the communication device 1, the header copy portion 15 and the packet transmission generation unit 13
to execute return transfer control.

In other words, the ladder copy section 15 copies the header added to the packet from the communication device 1 and outputs it to the packet transmission generation section 13. The packet transmission generation unit 13 adds the header portion copied by the header copy unit 15 to the control message to generate a control packet, and sends this control packet to the communication device 1 via the transmission path L31. Transmit.

As described above, since the communication device 3 performs return transfer of the received packet, there is no need to refer to a prepared table or chart regarding the header section when adding the header section related to the sender of the packet. Can be easily transferred.

Further, there is no need to operate an arithmetic processing unit such as a microcomputer, and the processing related to adding a header section for return transfer of a packet can be simplified.

Next, referring to FIG. 3, an explanation will be given of an example of the operation when a packet from the communication device 1 is relayed and transmitted to the communication device 5.

The communication device 3 includes information about a header added when relaying a packet from the communication device 1 and transmitting it to the communication device 5, and information about a header section added when relaying a packet from the communication device 5 and transmitting it to the communication device 1. It has a storage means for storing information regarding the header section to be displayed. For example, transmission line LI3
When the header section added to the uplink packet transmitted via transmission path L35 is al, the header section added to the uplink packet transmitted via transmission path L35 corresponds to this header section a1. Stores information on a2. This storage means stores information regarding such a header section for each line. For example, if the communication device 3 is made by Tsushin@5
When a packet is received from the communication device 1 whose destination is , the header section a1 added to this packet is
2 is replaced and transmitted via the transmission line L35.

As described above, when a packet from one device is relayed and transmitted to another device, a new header section corresponding to the header section of the received packet, that is, the header section of the destination, is read from the storage means, and the header section is Since the numbers are changed, the packet relay process can be simplified. For example, if the storage means is a table or chart configured to select the same header as the header of a received packet, the header can be duplicated by a simple method such as modifying software. can.

Next, another embodiment of the present invention will be described with reference to FIG.

In the example shown in FIG. 4, the packet receiving unit 11 has a determining means for decoding the received packet and determining whether or not it is necessary to return and transfer the packet to the sending source. When it is determined that the received packet needs to be returned and transferred to the sending source, the header copy section 15 is operated to copy the header added to the packet, and the packet transmission generation section 13 is operated to copy the received packet. The header part of the packet is replaced with a new header part which is a duplicate of the header part of the packet, and the header part is transferred to the transmission source of the packet via the transmission path L3 + .

With the above configuration, it is possible to easily measure the delay time associated with packet transfer between both communication devices.

Furthermore, if the device configuration of this embodiment is applied to a so-called echo canceller transmission method in which digital signals are transmitted bidirectionally, functions related to so-called echo back, in which character information etc. transmitted from a terminal device are sent back from the center device to the terminal device, can be easily performed. can be realized.

In the embodiment shown in FIG.
was configured to monitor the load status within its own device 3, but
If an adjacent communication device, for example, a communication device 5, is configured to transmit a control packet regarding such status information to the communication device 3 when the communication device 5 is in a high load state or a failure state, the communication By decoding the content of the control packet from the communication device 5, the device 3 can remotely monitor the load state or failure state of the communication device 5, which is an adjacent device.

[Effects of the Invention] As described above, according to the present invention, when a packet is received from the other device, the header section added to the packet is copied by the copying means, and the copied header section is copied. Since the packets containing the data are forwarded to the device, there is no need to process the attachment or replacement of headers, which reduces the burden on the processing unit that oversees these processes, and speeds up the processing of packets. can be transferred to.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is a circuit diagram showing the internal configuration of a part of the header copy shown in Fig. 1, and Fig. 3 is an example to which the embodiment of Fig. 1 is applied. FIG. 4 is a block diagram showing another embodiment of the present invention, FIG. 5 is an explanatory diagram showing a conventional example,
FIG. 6 is an explanatory diagram of a packet. 13...Packet transmission generation unit 15...Header copy part 17...Return transfer control unit

Claims (2)

[Claims] (1) The line from one device to the other device and the line from the other device to the one device are transmitted via a transmission path in which the same channel number is set, and the header section containing the channel number is transmitted. In a packet communication device that performs communication using a packet formed with a message part, there is provided a copying means for copying a header part added to a received packet, and a copying means for copying a header part added to a received packet. 1. A packet communication device comprising: transmitting means for transmitting a packet toward a source thereof. (2) The copying means has a storage means that stores a new header corresponding to the header added to the received packet, and when the packet is received, the copying means stores the new header corresponding to the header added to the received packet. 2. The packet communication device according to claim 1, wherein the packet communication device selects a header portion that corresponds to the packet.