JP3116217B2 - Network system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a network system, and more particularly, to a network system including a packet transmission device for transmitting information by a packet communication system and a packet switching device for switching a received packet to a corresponding line according to a packet switching path. .

[0002]

2. Description of the Related Art Conventionally, in this type of network system, when packetized information is transmitted by a packet transmission apparatus by a packet communication system, a packet switching apparatus receives the packetized information and stores the information in a packet. By looking at the destination address described, the user exchanges packets received on the corresponding line according to the packet exchange route recorded therein.

In a network system composed of the above-described packet switching devices, when performing packet transmission via a plurality of devices, it is necessary to register a packet switching path in advance in order for each device to perform packet switching. .

In the registration of the packet switching path, when a new registration is required, the packet cannot be transmitted unless the registration of the packet switching path is completed at all the places where the packet switching is performed. in this case,
As for the registration status of the packet switching path, the worker verifies the registration work status verbally.

On the other hand, there is a method for automatically generating the above-mentioned packet switching path. In this method, in a packet network, each node having a switching function is provided with an automatic routing data generation function for connecting a source node to a destination node.

The routing data automatic generation function includes a relay route search function for creating a relay route list from each source node to a destination node, a representative route selection function for determining a representative route from the relay route list, and a routing process from the representative relay route. It has a sub-function consisting of a routing table creation function to create data, and for each destination node of each source node,
The route is selected in the order of the route having the representative relay route with the highest priority, and the routing data is determined.

That is, the routing data automatic generation function checks for each node registered in the node configuration information whether or not there is a transit route that can be routed to all nodes except itself, and based on the check result, Automatically generates node routing data. This method is disclosed in JP-A-7-15469.

There is also a method of automatically performing a change registration of a route in a packet switching communication control device for selecting a route of a packet. The communication control device for packet switching includes a line control unit that performs line control corresponding to the data terminal device,
A line multiplexing unit that multiplexes / demultiplexes packets on a plurality of lines, a switching unit that performs packet switching, a memory that stores a control table and the like for performing packet switching, an input / output device, an internal bus, And a communication control unit for packet switching which communicates with the communication control unit for packet switching to be connected.

A management table for selecting a route of a packet is provided in the memory of the main body of the above-mentioned communication control unit for packet switching. This is performed autonomously and dynamically based on the data terminal device number and the packet switching communication control device number included in the packet input from the section.

That is, when a call request packet is transmitted from a data terminal device for communication, the number of the own data terminal device included in the header of the packet is extracted, and the packet exchange communication packet is transmitted. The management table is autonomously and dynamically generated by registering the number of the data terminal device accommodated in the control device and the communication control device number for packet switching in the management table each time.

Therefore, every time a data terminal device is relocated or expanded, the registration change process of the data terminal device is performed from the input / output device of the packet switching communication control device main body, and the change information is transmitted to all the packet switching communication control devices. You do n’t have to make any changes,
The maintenance-free communication control device for packet switching is realized. This technology is disclosed in
It is disclosed in Japanese Patent Publication No. 240237.

[0012]

In the conventional network system described above, when performing packet transmission via a plurality of devices, it is necessary to register a packet switching path in advance in order for each device to perform packet switching. The operator verbally verifies the registration state of the packet switching path. Therefore, if the verbal confirmation by the operator is insufficient, or if the confirmation is omitted, each device may not be able to exchange packets.

In the case of automatically generating a packet switching path registration for performing packet switching from node configuration information, when a device newly joining the network comes out, a new registration is required. There is no method for confirming the registration status of the related device at the point where transmission / reception / relaying of a packet relating to a new portion is performed at this time.

An object of the present invention is to solve the above-mentioned problems and to provide a network system capable of confirming a packet switching path registration state and a packet switching path (transmission path) from a transmission source to a transmission destination. It is in.

[0015]

A network system according to the present invention is a network system including a plurality of packet switching devices for switching a received packet to a corresponding line based on a packet switching route registered in advance. Transmitting / receiving means for transmitting and receiving an exchange confirmation test packet for confirming the registration state of the packet exchange path, and determining whether or not the exchange confirmation test packet received from the other apparatus by the transmission / reception means is addressed to its own station. Determining means for determining whether or not it is possible to exchange the test packet for exchange confirmation to a transmission destination based on the packet exchange path when it is determined that the exchange confirmation test packet is not addressed to the own station, A response packet to the test packet for exchange confirmation is created according to the determination result of the determination unit and the determination result of the determination unit. And returning means for returning to the sender of the replacement confirmation test packet includes a plurality of packet switching devices, respectively.

In another network system according to the present invention, in addition to the above configuration, a transmission path of the exchange confirmation test packet and another device based on the contents of the response packet returned from the return means of another device. Each of the plurality of packet switching apparatuses is provided with means for determining and displaying the switching path registration status of the plurality of packet switching apparatuses.

That is, in the network system of the present invention, conventionally, the exchange route is registered automatically at the time of packet exchange. However, since there is no method for confirming the registered state of the exchange route at the transmission source, the exchange confirmation test is performed. By providing a function of transmitting and receiving a packet and a function of returning a response to the test packet, the registered state of the exchange path can be confirmed at the transmission source.

The transmission source has a function of determining the transmission route and the exchange route registration status from the returned response packet, and displaying the transmission route and the exchange route registration status. As a result, it is possible to confirm the registered state of the packet switching path from the source to the destination and the packet switching path (transmission path).

[0019]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of one embodiment of the present invention. In the figure, a station A (hereinafter, referred to as a transmitting station A), which is a packet switching device constituting a network system, includes an exchange confirmation test packet transmitting / receiving unit 11, a packet exchange unit 12, a packet exchange table 13, an exchange confirmation test packet It is configured to include a processing unit 14 and a packet transmitting / receiving unit 15.

A station B (relay station or receiving station), which is a packet switching device constituting the network system
Comprises an exchange confirmation test packet transmitting / receiving unit 21, a packet switching unit 22, a packet exchange table 23, exchange confirmation test packet processing units 24 and 26, and packet transmitting / receiving units 25 and 27.

Referring to FIG. 1, the operation of confirming the registration state of the packet switching path according to one embodiment of the present invention will be described.

When a packet is transmitted from transmitting station A, B
An exchange confirmation test packet having a packet exchange confirmation test packet transmission function and a collation function for confirming the registration state of the packet exchange path registration information required for normal packet exchange and reception at the station. The transmission / reception unit 11 transmits a packet whose packet type is an exchange confirmation test packet.

In this case, when the transmitting station A reads the destination of the packet, the packet is exchanged from the packet exchange unit 12 according to the exchange route registered in the packet exchange table 13 to the exchange confirmation test packet processing unit 14. Is passed.

The exchange confirmation test packet processing unit 14 passes the packet from the packet exchange unit 12 as it is,
Via the packet transmitting / receiving unit 15, the corresponding line, ie, B
Sent to the station.

At the station B, the packet from the transmitting station A is received by the packet transmitting / receiving section 25, and the received packet is passed to the exchange confirmation test packet processing section 24. The exchange confirmation test packet processing unit 24 reads the packet type from the received packet. If the packet is an exchange confirmation test packet, it reads the destination continuously from the packet and determines whether the packet is addressed to its own station or exchanged.

When the exchange confirmation test packet processing unit 24 determines that the exchange is an exchange, the packet exchange table 23 checks the registered state of the packet exchange table 23 to confirm whether or not an exchange route to the destination is registered in the packet exchange table 23.

In this case, the exchange confirmation test packet processing unit 24 returns the confirmed result to the transmitting station A as a confirmation result response packet. If the exchange route is registered, the exchange confirmation test packet processing unit 24 passes the packet to the packet exchange unit 22. The packet switching unit 22 transmits the packet to the packet switching table 23 via the switching confirmation test packet processing unit 26 and the packet transmitting / receiving unit 27.
Is exchanged with the corresponding line registered in, that is, the station C. On the other hand, if the exchange route is not registered, the exchange confirmation test packet processing unit 24 discards the packet.

The exchange confirmation test packet processing unit 24
When it is determined that the received packet is addressed to its own station, the packet is passed to the exchange confirmation test packet transmitting / receiving section 21 via the packet switching section 22 and a response packet to the received packet is returned to the transmission source, that is, the transmission station A.

The exchange confirmation test packet processor 14 determines whether the packet returned from the station B is a confirmation result response packet or a response packet, and then passes the returned packet to the exchange confirmation packet transmitter / receiver 11. The exchange confirmation packet transmission / reception unit 11 determines from the determination result of the exchange confirmation test packet processing unit 14 how far the exchange route has been registered, and which route has been transmitted, and displays the determination result on a display unit (not shown). I do.

FIG. 2A is a diagram showing the structure of an exchange confirmation test packet according to one embodiment of the present invention, and FIG.
FIG. 2 is a diagram illustrating a configuration of a confirmation result response packet according to an embodiment of the present invention, and FIG. 2C is a diagram illustrating a configuration of a response packet according to an embodiment of the present invention.

In these figures, the exchange confirmation test packet includes a destination address 31, a source address 32,
Packet type 33, packet serial number 34, other 35
And a data section 36 (see FIG. 2A).

The destination address 31 indicates the address of the station to be confirmed. In this embodiment, the address of the station B or the address of the station C is written. The source address 32 indicates a source address, and in this embodiment, the address of the transmitting station A is written.

The packet type 33 indicates the type of the packet. In this embodiment, information indicating the exchange confirmation test packet, for example, "AA" is written. Packet sequence number 34
Indicates a number managed by the transmission source (the transmitting station A in this embodiment). Incidentally, the data section 36 stores arbitrary data.

The confirmation result response packet has a destination address 41
, A source address 42, a packet type 43, a packet serial number 44, a destination address 45, and a received exchange confirmation test packet 46 [see FIG. 2 (b)]. ].

The destination address 41 indicates the address of the destination to be returned, and in this embodiment, the address of the transmitting station A is written. The source address 42 indicates the address of the received location. In this embodiment, the address of the station B or the address of the station C is written as the source address.

The packet type 43 indicates the type of the packet. In this embodiment, information indicating the confirmation result response packet, for example, "BA" is written if exchange is possible, and "BB" is written if exchange is impossible. It is. The packet sequence number 44 indicates a number managed by the transmission source (station B or station C in this embodiment).

The destination address 45 indicates the destination address of the line that has received the exchange confirmation test packet. In the present embodiment, for example, in the case of the station B, if the signal is received from the line with the transmission station A, the transmission station A Is written. The exchange confirmation test packet 46 is an exchange confirmation test packet shown in FIG. 2A, and is added after the header portion.

The response packet includes a header portion including a destination address 51, a source address 52, a packet type 53, a packet serial number 54, and a destination address 55,
It comprises a received exchange confirmation test packet 56 [see FIG. 2 (c)].

The destination address 51 indicates the address of the destination to be returned, and in this embodiment, the address of the transmitting station A is written. The source address 52 indicates the address of the received location. In this embodiment, the address of the station B or the address of the station C is written as the source address.

The packet type 53 indicates the type of the packet. In this embodiment, information indicating a response packet, for example, "CA" if receivable, "C" if receivable
B "is written respectively. The packet sequence number 54 indicates a number managed by the transmission source (station B or C in this embodiment).

The destination address 55 indicates the destination address of the line that has received the exchange confirmation test packet. In this embodiment, for example, in the case of the station B, if the signal is received from the line with the transmission station A, the transmission station A Is written. The exchange confirmation test packet 56 is an exchange confirmation test packet shown in FIG. 2A, and is added after the header portion.

1 and 2 (a) to 2 (c), a method of determining the transmission path from the packet in the exchange confirmation packet transmitting / receiving unit 11 shown in FIG. 1 will be described.

The exchange confirmation packet transmitting / receiving unit 11 transmits the source address 42, which is the header of the returned "confirmation result response packet" (see FIG. 2B) and "response packet" (see FIG. 2C). 52, the packet types 43 and 53, and the receiving party addresses 45 and 55, the transmission route is sequentially determined, and how far exchange can be performed is determined.

For example, when the exchange station test packet is transmitted from the transmission station A to the station C, first, if the exchange station B is exchangeable, the exchange station "exchange result confirmation packet [packet type] : Exchangeable (BA)]] is returned. Subsequently, a "response packet" indicating that reception is possible (CA) or reception is not possible (CB) is returned from the station C. On the other hand, if the exchange B is not exchangeable, the exchange-rejected “confirmation result response packet [packet type: exchange impossible (BB)]” is returned from the exchange B.

In the former case, the exchange confirmation packet transmitting / receiving unit 1
In the case of No. 1, it is determined from the returned packet that the path from the transmitting station A to the station B, from the station B to the station C, is transmitted, and the path is transmitted to the station C. In addition, whether or not transmission is possible is determined based on the state of the station C (receivable or non-receivable).

In the latter case, the exchange confirmation packet transmitting / receiving unit 1
1 indicates that the transmitted packet is transmitted from the transmitting station A to the station B from the returned packet, and that the address and transmission route of the destination to be transmitted are not registered in the packet exchange table 23 at the station B. I do.

As described above, the exchange confirmation test packet transmitting / receiving unit 11 has the function of transmitting and receiving the exchange confirmation test packet and the function of determining and displaying the registration status of the transmission path and the exchange path from the response packet returned from the transmitting station. By providing the exchange confirmation test packet processing unit 24 with a function of returning a response to the exchange confirmation test packet, packet transmission is performed via a plurality of devices in a network composed of packet switching devices. By transmitting the exchange confirmation test packet from the transmitting station A, the exchange path registration state for packet exchange in each device can be confirmed.

When a new packet is to be transmitted from the transmitting station A or when a packet is to be transmitted from a new station, the packet switching apparatus and the receiving station in the transmission path are registered in advance in the packet switching path. Since the status can be confirmed by the transmitting station A, the transmitting station A can determine whether or not to transmit a packet.

[0049]

As described above, according to the present invention, in a network system including a plurality of packet switching devices for switching a packet received on the basis of a packet switching route registered in advance to a corresponding line, a packet in another device is exchanged. Transmitting / receiving means for transmitting / receiving an exchange confirmation test packet for confirming the registration state of the exchange path, and determining means for determining whether or not the exchange confirmation test packet received from the other apparatus by the transmission / reception means is addressed to the own station; Determining means for determining whether or not exchange of a test packet for exchange confirmation to a transmission destination is possible based on a packet switching path when the determination means determines that the packet is not addressed to the own station; A response packet to the exchange confirmation test packet in accordance with the judgment result of the above and returns the packet to the source of the exchange confirmation test packet. By providing a stage in a plurality of packet switching devices each, there is an effect that it is possible to verify the packet switched path registration status and packet switching route to the destination in the source (transmission path).

[Brief description of the drawings]

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

2A is a diagram illustrating a configuration of an exchange confirmation test packet according to an embodiment of the present invention, FIG. 2B is a diagram illustrating a configuration of a confirmation result response packet according to an embodiment of the present invention, and FIG. FIG. 5 is a diagram illustrating a configuration of a response packet according to an embodiment of the present invention.

[Explanation of symbols]

 11, 21 exchange confirmation packet transmission / reception unit 12, 22 packet exchange unit 13, 23 packet exchange table 14, 24, 26 exchange confirmation test packet processing unit 15, 25, 27 packet transmission / reception unit

Claims (5)

(57) [Claims] 1. A network system including a plurality of packet switching apparatuses for switching a packet received based on a packet switching path registered in advance to a corresponding line, and confirming a registration state of the packet switching path in another apparatus. Transmitting and receiving means for transmitting and receiving an exchange confirmation test packet for determining whether or not the exchange confirmation test packet received from the other apparatus from the other device is addressed to the own station; and A determination unit for determining whether or not the exchange confirmation test packet can be exchanged for a destination based on the packet exchange path when it is determined that the packet is not addressed to the destination; a determination result of the determination unit; and a determination by the determination unit. Returning a response packet to the exchange confirmation test packet according to the result and returning the response packet to the source of the exchange confirmation test packet Means for each of the plurality of packet switching devices. And means for discriminating and displaying the transmission path of the exchange confirmation test packet and the exchange path registration state of the other apparatus based on the contents of the response packet returned from the return means of the other apparatus. 2. The network system according to claim 1, wherein the network system is included in each of a plurality of packet switching devices. 3. The packet switching device according to claim 1, wherein the determination unit determines that the exchange confirmation test packet can be exchanged with the transmission destination. 3. The network system according to claim 1, wherein each of the network systems is included. 4. The exchange confirmation test, wherein the return means creates the response packet including information indicating whether or not the packet can be received when the determination means determines that the packet is addressed to the own station. The network system according to any one of claims 1 to 3, wherein the network system is configured to return the packet to a transmission source. 5. The exchange confirmation test packet, wherein the return unit creates the response packet including a determination result of the determination unit indicating whether the exchange confirmation test packet can be exchanged with a destination. The network system according to any one of claims 1 to 4, wherein the network system is configured to return to a transmission source.