JP3533493B2 - Protocol connection setting system and setting method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packet in which two identical packet communication control devices are provided in case of failure occurrence, and one of the two packet communication control devices is a working system and the other is a standby system. In a communication system having a communication control device, a system and method for setting a protocol connection between a standby packet communication control device and a one-way packet communication control device when a failure occurs in an active device .

[0002]

2. Description of the Related Art In preparation for a failure, ITU-T Recommendation Q.
Two packet communication control devices each including the 2110 are arranged, one of the two packet communication control devices is used as a packet active communication control device, and the other of the two packet communication control devices is used as a standby packet communication device. A communication system serving as a control device is provided. In this communication system, in the conventional setting system for setting a protocol connection between the standby packet communication control device and the 1-opposite packet communication control device when a failure occurs in the active system device, I was setting up a connection. Generally, when a failure occurs in the active packet communication control device, the standby packet communication control device sends 1 connection setting packet to the opposite packet communication control device.
One is transmitted and one is received by the opposite packet communication control device, and is reset by temporarily disconnecting the protocol connection due to an abnormality in the sequence number of the packet. Then, the upper layer protocol is used to set the protocol connection again. It was

[0003]

However, in the above-mentioned conventional system, even though only one connection setting packet is transmitted from the standby system device to one opposite packet communication control device, the Q. Depending on the reception status variable of 2110, the protocol connection may not be immediately disconnected, and then the connection may be disconnected only after waiting for the occurrence of some communication error. In that case, the connection is reset. There was a problem that processing was delayed.

Therefore, an object of the present invention is to solve these conventional problems, to promptly and actively disconnect the connection without depending on the state of the one-way packet communication control device, and then perform the resetting. By doing so, it is possible to provide a protocol connection setting system and a setting method capable of shortening the time from the failure to the resetting of the protocol connection.

[0005]

To achieve the above object, in the protocol connection setting system of the present invention, a protocol connection setting unit is newly provided as a mechanism for transmitting a plurality of connection start packets, and the protocol connection setting unit is also provided. Instructs the packet creation unit to use a sequence number different from the transmission of two connection setting packets, and continuously transmits two connection setting packets to the opposite station, or the protocol connection setting unit first transmits one connection setting packet. And the sequence number to the packet creating unit, and as a result of judging the type of the packet sent from the opposite station, the packet creating unit is instructed to use a sequence number different from the transmission of another connection setting packet.

Further, according to the protocol connection setting method of the present invention, when a failure occurs in the active packet communication control device, the standby packet communication control device sends a plurality of connections having different sequence numbers to one opposite packet communication control device. Send a setting packet. Alternatively, one connection setting packet is sent from the standby packet communication control device to one opposite packet communication control device and
It is determined whether or not the connection is disconnected according to the response packet type from the opposite packet communication control device, and if the connection is not disconnected, the connection setting packet with a different sequence number is sent to the one opposite packet communication control device. To do. This enables prompt and active connection disconnection when a failure occurs in the active packet communication control device, and as a result, prompt connection after the failure occurs in the active packet communication control device. It is always possible to reset.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. (First Embodiment) FIG. 1 is a block diagram of a protocol connection setting system showing a first embodiment of the present invention. In FIG. 1, the packet communication control device 11 includes a newly provided protocol connection setting unit 24, a setting flag 25, a packet creating unit 23, and a packet transmitting unit 2.
2, packet receiving unit 26, buffer 21, buffer 2
8, for example ITU-T Recommendation Q. The communication protocol processing unit 27 that performs processing according to 2110, for example, the reception state variable register 29 that holds VR (SQ) is provided. In the conventional system, since only one connection start packet was sent for resetting the connection, the communication protocol processing unit 27, which is a normal protocol operation, processed this. However, in the present embodiment, since a plurality of connection start packets are sent out, the protocol connection setting unit 24 is provided as a mechanism therefor.

When the protocol connection setting unit 24 receives an instruction to switch the active system from the upper layer triggered by a failure in the active system via the signal line 35, the protocol connection setting unit 24 transmits the signal via the signal line 34.
One connection setup packet (eg ITU-T
Q. Based on the 2110 specifications, the packet generation unit 23 is instructed to transmit a BGN PDU) and a different sequence number of the packet, and the setting flag 25 is set to “disconnecting” via the signal line 36. When receiving various instructions from the upper layer via the signal line 42, the communication protocol processing section 27 can also instruct the packet creating section 23 to send out various packets via the signal line 37. When receiving an instruction to transmit a connection setting packet from the protocol connection setting unit 24 via the signal line 34, the packet creating unit 23 creates a connection setting packet including the instructed sequence number, and via the signal line 33. It is sent to the packet transmitter 22.

Further, the packet creating section 23 uses the signal line 37.
When various packet transmission instructions are received from the communication protocol processing unit 27 via the, various packets are created and sent to the packet transmitting unit 22 via the signal line 33. The packet transmitter 22 uses the signal line 33 to transmit the packet generator 2
The packet received from No. 3 is accumulated in the buffer 21 via the signal line 32, and the packet is sent out to the partner station via the signal line 31. The packet receiving unit 26 receives the packet transmitted from the partner station via the signal line 38,
Packets are accumulated in the buffer 28 via the signal line 4
After transmitting the packet to the communication protocol processing unit 27 via 0, the accumulated packet is released from the buffer 28. The communication protocol processing unit 27 analyzes the packet received through the signal line 40, and when the packet is a connection setting rejection packet (for example, BGREJ PDU based on the ITU-T Q.2110 specification), the signal line 43.
The protocol connection setting unit 24 is inquired via the command whether or not the connection is being cut. If the result is that the connection is being cut, the setting flag 25, “the connection is being cut”, is cleared, and the connection is cleared. After resetting, a response to the active system switching instruction is returned via the signal line 35, and in the case of other packets, for example, ITU-T Recommendation Q. It includes a function of performing communication protocol processing according to 2110.

FIG. 2 is an operation sequence chart of the protocol connection setting system of the first embodiment.
Here, the communication operation procedure from the failure of the active packet communication control unit to the setting of the communication connection again in the standby packet communication control unit is shown. After recognizing the fault from the active system (step 100), the upper layer of the station A instructs the packet communication control unit 11 of the standby system to switch the active system (step 10).
1). Next, the communication control unit 1 that has received the active system switching instruction
The protocol connection setting unit 24 of No. 1 uses the signal line 36.
“Disconnecting” is set in the setting flag 25 via the (step 102), and the packet creating unit 23 is instructed to send two connection setting packets and different sequence numbers of the respective packets, and the packet creating unit 23
One connection setting packet is created, and the two connection setting packets are transmitted from the packet transmitter 23 to the partner station B (step 103).

Next, the packet receiving unit 26 of the B station temporarily stores the received connection setting packet in the buffer 28 and then transfers it to the communication protocol processing unit 27. The communication protocol processing unit 27 stores the sequence number of the received connection setting packet and the reception state variable register 29, for example, ITU-T Q. Two
Based on the 110 specifications, two connection setting packets (SQ = A and SQ = B) are respectively VR (SQ).
The value is compared with A (steps 104 and 106). As a result of the comparison, when the two are the same, the opposite station A is instructed by instructing the packet creation unit 23 to transmit a connection setting response packet (for example, BGNAK PDU based on the ITU-T Q.2110 specification). A connection response packet is transmitted (step 105). If the comparison results in different values, for example, ITU-
T Q. Based on the 2110 specifications, the packet creation unit 23 is instructed to transmit the connection setup rejection packet to transmit the connection rejection packet to the opposite station A (step 107) and notify the upper layer of the disconnection of the connection (step 108). .

Next, the packet receiving unit 26 of the A station temporarily stores the received connection setting packet in the buffer 28 and then transfers it to the communication protocol processing unit 27. If it is a connection setting response packet, it is discarded (step 109), and if it is a connection setting rejection packet, it is notified to the protocol connection setting unit 24 via the signal line 43, and "connection is being disconnected" stored in the setting flag 25. Is canceled (Step 11
0). By the above operation, the stations A and B can quickly disconnect the connection, and finally the connection is reset by the upper layer of the station B as follows. That is, the upper layer of the B station issues a connection setting instruction to the packet communication control device 11 again (step 112), whereby the packet communication control device 1
1 is a connection setup packet (BGN PD
U) is transmitted (step 113). Upon receiving the connection setup packet, station A sends a connection setup response packet (BGNAK PDU) to station B (step 115), and returns a response to the active system switching instruction to the upper layer via signal line 35. (Step 114). When the station B receives the connection setup response packet, it returns the connection setup response to the upper layer (step 116).

(Second Embodiment) FIG. 1 is also applicable to the second embodiment. In the second embodiment of FIG. 1, the protocol connection setting unit 24 uses the signal line 35.
When a working system switching instruction is received from the upper layer via a working system failure via one of the connection systems, one connection setting packet (for example, ITU-T Q.21) is sent via the signal line 34.
Based on the 10 specifications, the packet generation unit 23 is instructed of the transmission of the BGN PDU) and the sequence number of the packet,
“Disconnecting” is set in the setting flag 25 via the signal line 36. In addition, the protocol connection setting unit 24 uses the connection setting response packet (for example, ITU-T Q.2110) from the communication protocol processing unit 27.
According to the specification, when the reception notification of the (BGNAK PDU) is received and the setting flag 25 is “connection being disconnected”, again, one connection setting packet is transmitted via the signal line 34 and one of the previously transmitted packets is transmitted. The packet creating unit 23 is instructed to use a number different from the sequence number.

That is, the difference between the second embodiment and the first embodiment is that the first embodiment continuously transmits two connection setting packets to the B station, whereas the second embodiment
In the embodiment, first, only one connection setting packet is transmitted, and then another one connection setting packet is retransmitted according to the result of the packet type determination. The above-described packet type determination processing is performed by the communication protocol processing unit 27. That is, the communication protocol processing unit 27 determines the type of the transmitted packet as a result of the comparison of the initially transmitted connection setting packet at the B station.
In both the first embodiment and the second embodiment, the packet creation unit 23, the protocol connection setting unit 24, and the communication protocol processing unit 27 are arranged in separate blocks in FIG. It is also possible to implement each processor of 1 by one processor in the packet communication control unit.

FIG. 3 is an operation sequence chart of the protocol connection setting system showing the second embodiment of the present invention. Here, a communication operation procedure from the failure of the active packet communication control unit to the setting of the communication connection again in the standby packet communication control unit will be described. After recognizing the fault from the active system (step 100), the upper layer of the station A instructs the packet communication control unit 11 of the standby system to switch the active system (step 10).
1). Next, the communication control unit 1 that has received the active system switching instruction
The protocol connection setting unit 24 of No. 1 uses the signal line 36.
The connection flag is set to "during connection disconnection" via the (step 102), and the packet creation unit 23 is instructed to transmit one connection setting packet and the sequence number. The packet creation unit 23 creates two connection setup packets, and the packet transmission unit 22 creates the one connection setup packet (BGN PDU (S
Q = A)) to the partner station B (step 10)
3).

Next, the packet receiving unit 26 of the B station temporarily stores the received connection setting packet in the buffer 28 and then transfers it to the communication protocol processing unit 27. In the communication protocol processing unit 27, for example, the sequence number of the received connection setting packet and the VR (SQ) value (SQ stored in the reception state variable register 29 are stored.
= A) (step 104). As shown in FIG. 3, as a result of the comparison, if the two values are the same, the packet creation unit 23 is instructed to transmit the connection setting response packet, thereby transmitting the connection setting response packet to the opposite station A ( Step 105). Here, if they are not the same, the process proceeds to step 109.

Next, the packet receiving unit 26 of the A station temporarily stores the received connection setting packet in the buffer 28 and then transfers it to the communication protocol processing unit 27. The communication protocol processing unit 27 determines the type of the packet (step 106), and when the received connection setting packet is a connection setting response packet, notifies it to the protocol connection setting unit 24. When the setting flag 25 is “disconnecting”, the protocol connection setting unit 24 transmits a single connection setting packet and a sequence number (S) different from the sequence number of the connection setting packet transmitted above.
Q = B) is instructed to the packet creating unit 23. The packet creating unit 23 creates two connection setting packets,
The packet transmission unit 22 transmits the one connection setting packet to the other station B (step 107).

Next, the packet receiving unit 26 of the B station temporarily stores the received connection setting packet in the buffer 28 and then transfers it to the communication protocol processing unit 27. In the communication protocol processing unit 27, the sequence number of the received connection setting packet and the reception state variable register 29
Is compared with, for example, a VR (SQ) value (= A) stored in (step 108). As shown in FIG. 3, when the comparison results in different values, for example, ITU-T Q. Two
110 based on the 110 specification, by instructing the packet creation unit 23 to transmit a connection setup rejection packet (for example, BGNREJ PDU based on the ITU-T Q.2110 specification), the connection setup rejection packet is sent to the opposite station A. It is transmitted (step 109) and the upper layer is notified of the disconnection of the connection (step 110).

Next, the packet receiving unit 26 of the A station temporarily stores the received connection setting packet in the buffer 28 and then transfers it to the communication protocol processing unit 27. In the communication protocol processing unit 27, when the received connection setting packet is a connection setting refusal packet,
Protocol connection setting unit 24 via signal line 43
Is notified, and the “during connection disconnection” stored in the setting flag 25 is canceled (step 111). As described above, the stations A and B can disconnect the connection promptly, and finally the connection is reset by the upper layer of the station B as follows. That is, the upper layer of the B station again sets the packet communication control device 1
Issue connection setting instruction to 1 (step 11)
By doing so, the packet communication control device 11 sends a connection setup packet to station A (step 11).
3). When the station A receives the connection setup packet, it sends a connection setup response packet to the station B (step 115) and returns a working system switching instruction response to the upper layer via the signal line 35 (step 114). . When the station B receives the connection setting response packet, it returns the connection setting response to the upper layer (step 116).

[0020]

As described above, according to the present invention,
When a failure occurs in the active packet communication control device, the standby packet communication control device sends one connection setting packet with a sequence number to one opposite device, or two connection settings with different sequence numbers are set. By transmitting the packet, the protocol connection can always be immediately disconnected due to the abnormality in the sequence number of the packet received by the one opposite device. As a result, it is possible to shorten the time from the failure to the resetting of the protocol connection by the upper layer protocol.

[Brief description of drawings]

FIG. 1 is a block diagram of a packet communication control device in a switching system showing an embodiment of the present invention.

FIG. 2 is an operation sequence chart according to the protocol connection setting method according to the first embodiment of the present invention.

FIG. 3 is an operation sequence chart according to a protocol connection setting method showing a second embodiment of the present invention.

[Explanation of symbols]

11 ... Packet communication control device 21, 28 ... Buffer,
22 ... Packet sending unit, 23 ... Packet creating unit, 24 ...
Protocol connection setting unit, 25 ... Setting flag, 2
6 ... Packet receiving unit, 27 ... Communication protocol processing unit, 2
9 ... Reception state variable register, 31-43 ... Signal lines.

Front page continuation (56) References JP 10-303914 (JP, A) JP 10-262066 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04L 12 / 56 H04L 1/22 H04L 29/14 H04L 29/06-29/08

Claims (4)

(57) [Claims] 1. A protocol connection setting system for a packet communication control device having a redundant configuration in which two packet communication control devices are arranged in preparation for a failure occurrence, one of which is an active system and the other is a standby system, When a failure occurs in the active side device on the transmitting side, "connection disconnected" is set by the switching instruction to the standby system device, and multiple connection setting packets with different sequence numbers for sending to one opposite device are created. And a plurality of response packets returned from the one opposite device are analyzed. If one of the packets is a reject packet, the protocol connection setting unit indicates to the protocol connection setting unit , And if it is in the process of disconnecting, the communication protocol processing unit that releases it Protocol connection setting system characterized by comprising. 2. A protocol connection setting system of a packet communication control device having a redundant configuration in which two packet communication control devices are arranged in preparation for a failure occurrence, one of which is an active system and the other is a standby system, When a failure occurs in the active system device on the transmission side, a protocol connection setting unit for instructing the creation of a connection setup packet to which a sequence number for transmission to one opposite device is instructed by a switching instruction to the standby system device, (1) The type of the response packet returned from the opposite device is determined, and it is determined whether the connection is disconnected because the packet is a rejection packet. If the connection is not disconnected, the protocol connection setting is performed. To the above-mentioned 1 peer device of the connection setup packet with a sequence number different from the last time Protocol connection setting system characterized by comprising a communication protocol processing unit for instructing retransmission. 3. A protocol connection setting method for a packet communication control device having a redundant configuration in which two packet communication control devices are arranged in case of failure occurrence, one of which is an active system and the other is a standby system, The standby side packet communication control device sets a setting flag to “disconnecting” in response to an instruction to switch to the standby system due to a failure in the active system, and two different ones for transmitting to the opposite device. The packet creation unit is instructed to create a connection setup packet to which a sequence number is added, and the packet creation unit creates two connection setup packets and sends them to the one opposite device . The one opposite device receives the two received packets. The sequence number of the connection setup packet is compared with the VR (SQ) value stored in the reception state variable register, and the comparison Result, when the same is instructing transmission of the connection setting response packet to the packet creation unit, if different instructs the transmission of the connection setup rejection packet, the standby system transmission side packet communication control device If the received packet is a connection setting response packet, the standby side packet communication control device discards it, but if it is a connection setting refusal packet, the setting flag “disconnecting” is returned. A method for setting a protocol connection, characterized in that the connection is released and the connection between both stations is cut off, thereby waiting for the resetting of the connection from the one opposite device. 4. A protocol connection setting method of a packet communication control device having a redundant configuration in which two packet communication control devices are arranged in preparation for a failure occurrence, one of which is an active system and the other is a standby system. The transmission side packet communication control device of the standby system sets the setting flag to "disconnecting" in response to an instruction to switch to the standby system due to a failure in the active system, and 1 Connection setting packet for transmission to the opposite device And a sequence number to the packet creating unit, the packet creating unit creates two connection setting packets, and sends one of them to the one opposite device, and the one opposite device receives the first received packet. The sequence number of the connection setup packet is compared with the VR (SQ) value stored in the reception status variable register, and the comparison result If they are identical, but instructs the transmission of the connection setting response packet to the packet creation unit, if different instructs the transmission of the connection setup rejection packet, sent back to the sender packet communication control device of the standby system Then, the backup- side transmitting-side packet communication control device determines the type of the received packet, and if the packet is a connection setting response packet, confirms that the setting flag is "disconnecting", and The connection creation packet with a sequence number different from the sequence number sent to the packet creation unit, and the packet creation unit adds a sequence number different from the previous one to the other connection setup packet and sends it to the above-mentioned one opposite device. , If the result of discrimination of the packet type is connection setting reject packet, the above setting flag Release the "in connection cut" of grayed, cutting the connection between the two stations, the protocol connection setting method characterized by waiting for re-setting of the connection from the first counter device.