JP4509013B2 - Packet retransmission method and apparatus - Google Patents

Description

  The present invention relates to a packet retransmission method and apparatus, and more particularly to a packet retransmission method and apparatus for performing retransmission using a buffered transmission / reception packet for a failure occurring in a transmission apparatus in a network.

  Examples of the packet retransmission technique as described above include those according to conventional examples [1] and [2] described below.

Conventional example [1]: (not shown)
A conventional transmission apparatus is equipped with a port mirroring function for retransmitting transmitted / received packets in real time.

  However, the port mirroring function can only retransmit and monitor the transmitted and received packets in real time, and as a result, it can detect that a failure has occurred in the transmission device, but it is very difficult to identify the cause of the failure. It is.

Conventional example [2]: Fig. 9
In order to cope with the problem of the conventional example [1], a packet retransmission technique using a LAN fault monitoring device has already been proposed.

  9 (1) and 9 (2) are transmitted to the network NW, for example, with two transmission apparatuses 101 and 102 (hereinafter sometimes collectively referred to as reference numeral 100) connected to the network NW. 1 shows a LAN fault monitoring system including a LAN fault monitoring apparatus 400 as a packet retransmission apparatus that receives all packets and monitors the occurrence of a network (LAN) fault. This LAN fault monitoring device 400 includes a first LAN transmission / reception control device 410 and a second LAN transmission / reception control device 420 that control packet transmission / reception, a processor CPU, and a memory MEM inside, and a monitor 500 externally. The measuring instrument 600 is connected.

  When this LAN fault monitoring system is operating normally, the LAN fault monitoring apparatus 400 receives all packets sent from the transmission apparatuses 101 and 102 onto the network NW as shown in FIG. At the same time, the first LAN transmission / reception controller 410 buffers (b) the packet received in the internal memory MEM.

  On the other hand, as shown in FIG. 2 (2), for example, when a failure occurs in the transmission device 101 (c), the transmission device 101 sends a failure occurrence notification (d) to the network NW, which is monitored for LAN failure. Device 400 receives. When this failure occurrence notification (d) is detected by the processor CPU via the first LAN transmission / reception controller 410, the processor CPU instructs the first LAN transmission / reception controller 410 to stop buffering received packets (e). Then, the buffered data is read (f).

For example, the read data is displayed (g) on the monitor 500 connected to the outside or loaded (h) into the measuring device 600 to be used for analysis of the cause of the failure (for example, Patent Document 1). reference.).
JP-A-6-132960

  The above-mentioned Patent Document 1 can read a received packet buffered up to the time of occurrence of a failure in a certain transmission device, but uses a special device such as a LAN failure monitoring device and describes the contents as necessary. The maintenance person must confirm all while looking at the external monitor, or actually load the received packet into the external measuring instrument.

  Furthermore, when a failure occurs in the port of the transmission device, the failure notification cannot be received normally by the LAN failure monitoring device, so the range of received packets provided to identify the cause of the failure cannot be specified correctly There is.

  Therefore, according to the present invention, when a port failure occurs in a transmission device in a network, the packet is retransmitted by itself without specifying a special device such as a LAN failure monitoring device in order to identify the cause of the failure. It is an object of the present invention to provide a method and apparatus capable of performing the above.

 [1] In order to achieve the above object, a packet retransmission method (or apparatus) according to the present invention includes a first step (or means) for receiving a packet from a network via a working port, and the received packet. The second step (or means) for buffering, the third step (or means) for stopping the buffering when it detects that a failure has occurred in the working port, and the buffering by the time of the failure And a fourth step (or means) for sending at least a predetermined range of packets out of the packets to the external device through a spare port.

  This will be explained using the operation principle of the present invention shown in FIG. 1.The packet retransmission method (or apparatus) according to the present invention is realized in each of the transmission apparatuses 101 and 102 in the network NW (however, However, this is not a limitation.) For example, when the transmission apparatus 101 (the same applies to the transmission apparatus 102) is operating normally, as shown in FIG. 1A, in the first step (or means), the network interface NW is connected to the line interface unit 111. A packet is received (a) via the working port 201W. In the second step (or means), the received packet is buffered (b) in the internal memory MEM.

  On the other hand, as shown in FIG. 2 (2), for example, when a failure occurs (c) in the working port 201W of the transmission apparatus 101, the buffering of received packets is stopped (d) in the third step (or means). . In the fourth step (or means), at least a predetermined range of packets buffered up to the point of failure is sent (e) to the maintenance person terminal 300 which is an external device via the spare port 201P. .

  In the following description, the working port 201W and the spare port 201P may be collectively referred to by reference numeral 201.

  Thus, in the packet retransmission method (and apparatus) of the present invention, when a port failure occurs in the transmission devices 101 and 102 in the network NW, the LAN shown in FIG. 9 is used to identify the cause of the failure. It is possible to retransmit the packet to the external device by itself without using a special device such as the failure monitoring device 400.

 [2] In the above [1], the third step (or means) includes a step of transmitting a failure notification to the external device together with the stop of the buffering, and the fourth step (or means) includes The command may be executed based on a packet retransmission setting command generated from the external device that has received the failure notification.

  That is, as shown in FIG. 1 (2), in the third step (or means) of the transmission device 101 (the same applies to the transmission device 102), the maintenance person terminal which is an external device is used together with the buffering stop (d). A failure notification (f) is sent to 300. Receiving the failure occurrence notification (f), the maintenance person terminal 300 transmits a packet retransmission setting command (g) instructing the transmission apparatus 101 to retransmit the packet via the spare port 201P.

  In the fourth step (or means), the packet within the predetermined range is sent (e) to the maintenance person terminal 300 via the spare port 201P at the timing when the packet retransmission setting command (g) is received.

  In this way, an external device such as the maintenance person terminal 300 can instruct retransmission of a received packet for investigation / analysis at an arbitrary timing after the investigation of the cause of failure and preparation for analysis are completed, for example.

 [3] In [2] above, the packet retransmission setting command may specify the predetermined range.

  In this case, since an external device such as the maintenance person terminal 300 can specify the range shown in (A) to (C) below, for example, with the packet retransmission setting command (g), the maintenance person can investigate the cause of the failure. And in the analysis, it is possible to obtain a received packet for investigation / analysis in an arbitrary range.

  (A) All received packets from the start of buffering to the time of failure.

  (B) Some received packets from the start of buffering to the time of failure. For example, Xth to Yth (X and Y are arbitrary natural numbers) received packets, etc., starting from the received packet at the time of failure occurrence (buffering stop time).

  (C) A single received packet from the start of buffering to the point of failure. For example, the Xth one received packet, etc. starting from the received packet at the time of failure occurrence (buffering stop time).

 [4] In the above [2], the external device may be a maintenance person terminal connected in advance to the spare port.

  That is, for example, in the conventional example shown in FIG. 9, in order for the maintenance person to identify the cause of the failure that occurred in the transmission apparatus 101 from the received packet, the LAN that buffers all received packets sent out on the network NW Although it was necessary to additionally install the failure monitoring device 400 and display on the external monitor 500, in the present invention, as shown in FIG. 1, by the packet retransmission setting command (g) from the maintenance person terminal 300, Since the packet can be sent directly from the transmission apparatus 101 in which the failure has occurred to the maintenance person terminal 300, the maintenance person easily obtains the received packet and investigates and analyzes the contents in the investigation and analysis of the cause of the failure. be able to.

 [5] Also, in the above [4], the spare port includes a plurality of ports, and the packet retransmission setting command connects the predetermined range of packets to the maintenance person terminal in the spare port. It may be instructed to send to an external device different from the maintenance person terminal via a port different from the other port.

  That is, for example, in the conventional example shown in FIG. 9, in order to identify the cause of the failure that occurred in the transmission device 101 by performing the reproduction test, a buffer is used by using the LAN failure monitoring device 400 additionally provided in the network NW. The ringed received packet has to be once loaded into the external measuring device 600 and transmitted to a transmission device which is another external device. In the present invention, as shown in FIG. The packet retransmission setting command (g) from the transmission apparatus 101 in which the failure has occurred via a spare port (not shown) different from the spare port 201P, a transmission apparatus (not shown) different from the maintenance person terminal 300. Since the packet can be sent directly to the device, the maintenance person must determine whether or not a failure occurs in the other transmission device in the same manner as the transmission device 101 by performing a port failure detection or the like. And cause of failure It can be the transmission apparatus 101 to identify immediately whether or not the received packet.

  According to the present invention, when a port failure occurs in a transmission device or the like in a network, it is not necessary to use a special device such as a LAN failure monitoring device to identify the cause of the failure and is affected by the failure. Therefore, the received packet can be correctly buffered and the packet can be retransmitted by itself, thereby improving the efficiency of analyzing the cause of the failure.

  Furthermore, since the packet retransmission timing, retransmission range, and transmission destination can be instructed based on the packet retransmission setting command, the maintenance person can obtain the received packet appropriately and easily in the investigation and analysis of the cause of the failure. In the reproduction test, the packet can be retransmitted directly to another transmission device to immediately determine whether the cause of failure is a received packet. It is possible to improve the convenience and work efficiency of the analysis and the reproduction test.

  The packet reproduction method and apparatus according to the present invention are realized in each of the transmission apparatuses 101 and 102 as described with reference to FIG. 1, and the embodiment and the packet retransmission operation example will be described below with reference to FIGS. Explained. However, the present invention is not limited to the transmission apparatus.

[1] Configuration example: Fig. 2
First, the configuration of the present embodiment will be described below with reference to FIG.

  Similar to the transmission apparatus 101 shown in FIG. 1, the transmission apparatus 100 shown in FIG. 2 includes a line interface unit 110 that transmits and receives packets, an internal memory MEM, and a processor CPU. A control unit 150 that controls the interface unit 110 is further provided. The line interface unit 110, the memory MEM, the processor CPU, and the control unit 150 are configured to be connected to each other by a common bus BUS.

  Here, the line interface unit 110 further includes, for example, ports 200_1 and 200_2 as active ports 200W and ports 200 including ports 200_3 to 200_6 as spare ports 200P, and transmission packets SND_PCKT and reception packets RCV_PCKT via the ports 200 Transmission / reception unit 120 that performs transmission / reception, buffering processing unit 130 that buffers the received packet RCV_PCKT in the memory MEM, and retransmission processing unit that extracts the buffered packet from the memory MEM and retransmits it via the transmission / reception unit 120 and the spare port 200P It has 140.

  In addition, the control unit 150 further receives a failure detection unit 160 that detects the failure of the working port 200W, a line interface control unit 170 that controls the line interface unit 110, and a packet retransmission setting command from an external device (not shown). A command receiving unit 180 that receives the command and a command processing unit 190 that performs a control instruction corresponding to the packet retransmission setting command to the line interface unit 110 are provided.

[2] Example of operation: Figures 3-8
Next, the operation of the embodiment of FIG. 2 will be described below with reference to FIGS.

  Here, FIG. 3 is a flowchart specifically showing the overall operation of the transmission apparatus 100 shown in FIG. 2, with the processes (steps S1 to S9) and the dotted line (2) indicated by the dotted line (1) in FIG. The processes shown (steps S1 to S5 and S10, 11 and S20) indicate packet retransmission processes (1) and (2) described below, respectively.

  Since various packet retransmission methods are conceivable, the method is not particularly limited to the following operation example.

[2.1] Packet retransmission processing example (1): Figs.
4 shows a line interface control unit 170 provided in the control unit 150, a buffering processing unit 130 and a retransmission processing unit 140 provided in the line interface unit 110, and a port 200_1 in the transmission apparatus 100 shown in FIG. ˜200_6 and the connection relationship between the memory MEM, more specifically, the received packet RCV_PCKT is fetched from the network NW via the ports 200_1 and 200_2 as the active ports 200W, and the ports 200_3 as the spare ports 200P In this example, the maintenance person terminal 300 is connected to a predetermined port 200_6 in advance.

  In FIG. 4, in order to simplify the drawing, the transmission / reception unit 120, the failure detection unit 160, the command reception unit 180, the command processing unit 190, and the processor CPU illustrated in FIG. 2 are omitted.

  First, when the transmission apparatus 100 is operating normally, that is, when there is no failure in the working port 200W, in step S1 shown in FIG. 3, the transmission / reception unit 120 receives a packet through the working port 200W. At the same time, the buffering processing unit 130 buffers the received packet RCV_PCKT in the memory MEM (step S2). Assuming that no port failure has occurred, the failure detection unit 160 repeats steps S1 and S2 without detecting a failure (step S3), and performs buffering each time a packet is received.

  On the other hand, when the failure detection unit 160 detects a failure (FIG. 4 (a)) in the port 200_1 in the working port 200W shown in FIG. 4 (step S3), the line interface control unit 170 performs the buffering processing unit. A buffering stop instruction (FIG. 4B) is issued to 130 (step S4), and the buffering processing unit 130 actually stops buffering packets (FIG. 4C) (step S5).

  Thereafter, the line interface control unit 170 determines whether the packet retransmission setting command function is invalid, that is, whether the packet retransmission range and the transmission spare port specified by the packet retransmission setting command generated from the maintenance person terminal 300 are invalid. If it is invalid, the line interface control unit 170 requests the retransmission processing unit 140 to transmit the packet from the port 200_6 (FIG. 4 (d)). (Step S7) and instructing retransmission of packets within a predetermined range (FIG. 4 (e)) (step S8).

  Then, the retransmission processing unit 140 reads out a predetermined range of packets buffered in the memory MEM (FIG. 4 (f)), and reads out to the maintenance person terminal 300 via the transmission / reception unit 120 and the port 200_6. The received packet is retransmitted (FIG. 4 (g)) (step S9).

[2.1.1] Example of processing flow for maintenance personnel terminal: Fig. 5
As shown in FIG. 5, the maintenance person terminal 300 receives the packet retransmitted from the transmission apparatus 100 (step S31), and investigates and analyzes the received packet (step S32).

  If the cause of the failure can be identified as a received packet (step S33), the transmission source transmission device of the packet causing the failure, that is, the operation of the transmission device that transmitted the packet to the transmission device 100 is stopped. (Step S34). The exchange with the maintenance person terminal 300 can be executed using the TRAP technology.

[2.2] Packet retransmission processing example (2): Figs.
FIG. 6 shows an example in which the working port 203W of the transmission device 103, which is an external device different from the maintenance person terminal 300, is connected to the network NW in addition to the connection relationship shown in FIG.

  Note that this transmission apparatus 103 may be one that does not implement the packet reproduction method and apparatus according to the present invention.

  First, the processing of steps S1 to S5 shown in FIG. 3 and (a) to (c) shown in FIG. 4 are the same as in the packet retransmission processing example (1). If it is determined in step S6 that the packet retransmission setting command function is valid, the transmission / reception unit 120 transmits a failure notification to the maintenance person terminal 300 via the predetermined spare port 200_6, and the packet retransmission setting illustrated in FIG. A process (step S20) is executed.

  In this packet retransmission setting process, the transmission device 100 responds to the failure occurrence notification by the maintenance operator terminal 300 instructing the packet retransmission range and its transmission reserve port (packet retransmission setting command (dotted line (g) in FIG. 1 (2)). ) Is received (step S21). If the packet retransmission setting command cannot be received, the reception is continued, but if received (step S22), the command reception unit 180 accepts the packet retransmission setting command and performs a corresponding process on the command processing unit 190. Then, the command processing unit 190 gives a control instruction to the line interface control unit 170 (step S24).

  When the packet retransmission setting command receives an instruction to retransmit all received packets from the start of buffering to the point of failure to the transmission apparatus 103 via the spare port 200_5 different from the port 200_6, for example, the line interface control The unit 170 requests the retransmission processing unit 140 to perform packet transmission setting such as a destination address (FIG. 6 (d)) so that the packet is retransmitted from the port 200_5 to the transmission device 103 (step S25), and Packet retransmission is instructed ((e) in the figure) (step S26).

  After that, in step S11 shown in FIG. 3, the retransmission processing unit 140 reads all the received packets in the specified range buffered in the memory MEM (FIG. 6 (f)), and transmits via the transmission / reception unit 120 and the port 200_5. The read packet is retransmitted to the transmission apparatus 103 without connection, for example (FIG. 6 (g)).

  In this example, the spare port 200_5 of the transmission device 100 and the active port 203W of the transmission device 103 are connected to the network NW, respectively, so that packets are retransmitted without connection. Needless to say, the spare port 200_5 of the transmission apparatus 100 and the working port 203W of the transmission apparatus 103 may be directly connected to retransmit the packet.

[2.2.1] Processing flow example of opposite transmission device: Fig. 8
As shown in FIG. 8, the transmission apparatus 103 receives the packet retransmitted from the transmission apparatus 100 (step S41). If the received packet causes a port failure as in the transmission device 100 (step S42), the cause of the failure can be immediately identified in the received packet (step S43). The failure recovery operation can be continued by limiting the target to only received packets.

  If no port failure occurs in the transmission device 103 (step S42), it is determined that the cause of the failure is not the received packet (step S43), so the maintenance person narrows down the analysis target to other than the received packet and performs failure recovery work. Can continue.

Note that the present invention is not limited to the above-described embodiments, and it is obvious that various modifications can be made by those skilled in the art based on the description of the scope of claims.

(Appendix 1)
A first step of receiving a packet from a network via a working port;
A second step of buffering the received packet;
A third step of stopping the buffering when detecting that a failure has occurred in the working port;
A fourth step of sending at least a predetermined range of packets buffered up to the time of the failure to an external device via a spare port;
A packet retransmission method comprising:
(Appendix 2) In Appendix 1,
The third step includes a step of transmitting a failure notification to the external device together with the stop of the buffering,
The packet retransmission method, wherein the fourth step is executed based on a packet retransmission setting command generated from the external apparatus that has received the failure notification.
(Appendix 3) In Appendix 2,
A packet retransmission method, wherein the packet retransmission setting command specifies the predetermined range.
(Appendix 4) In Appendix 2,
A packet retransmission method, wherein the external device is a maintenance person terminal previously connected to the spare port.
(Appendix 5) In Appendix 4,
The spare port includes a plurality of ports, and the packet retransmission setting command sends the packet within the predetermined range via a port different from the port connected to the maintenance person terminal among the spare ports. A packet retransmission method characterized by instructing transmission to an external device different from the maintenance person terminal.
(Appendix 6)
A first means for receiving a packet from a network via a working port;
A second means for buffering the received packet;
A third means for stopping the buffering when detecting that a failure has occurred in the working port;
A fourth means for sending at least a predetermined range of packets buffered up to the time of the failure to an external device via a spare port;
A packet retransmission apparatus comprising:
(Appendix 7) In Appendix 6,
The third means includes means for transmitting a failure notification to the external device together with the stop of the buffering;
A packet retransmission apparatus, wherein the fourth means is executed based on a packet retransmission setting command generated from the external apparatus that has received the failure occurrence notification.
(Appendix 8) In Appendix 7,
A packet retransmission apparatus, wherein the packet retransmission setting command specifies the predetermined range.
(Appendix 9) In Appendix 7,
The packet retransmission apparatus, wherein the external apparatus is a maintenance person terminal connected in advance to the spare port.
(Appendix 10) In Appendix 9,
The spare port includes a plurality of ports, and the packet retransmission setting command sends the packet within the predetermined range via a port different from the port connected to the maintenance person terminal among the spare ports. A packet retransmission apparatus characterized by instructing transmission to an external apparatus different from the maintenance person terminal.

FIG. 2 is a block diagram illustrating an operation principle of a packet reproduction method and apparatus according to the present invention. It is the block diagram which showed the Example of a structure of the packet reproduction method and apparatus concerning this invention. It is the flowchart figure which showed the whole operation | movement Example of the packet reproduction | regeneration method and apparatus based on this invention. FIG. 7 is a block diagram showing a packet retransmission processing example (1) of the packet reproduction method and apparatus according to the present invention. It is a flowchart figure which shows the processing flow of the maintenance person terminal in the packet reproduction | regeneration method and apparatus concerning this invention. FIG. 7 is a block diagram showing a packet retransmission processing example (2) of the packet reproduction method and apparatus according to the present invention. It is the flowchart figure which showed the Example of the packet retransmission setting process which concerns on this invention. It is a flowchart figure which shows the processing flow of the opposite transmission apparatus in the packet reproduction | regeneration method and apparatus concerning this invention. FIG. 10 is a block diagram showing a conventional example [2] of packet retransmission technology.

Explanation of symbols

100, 101-103 Transmission equipment
110, 111 line interface
120 Transceiver
130 Buffering processor
140 Retransmission processing part
150 Control unit
160 Fault detection unit
170 Line interface controller
180 Command receiving part
190 Command processing section
200W, 201W, 203W working port
200P, 201P Spare port
200, 200_1 ~ 200_6, 201 ports
300 Maintenance terminal
400 LAN fault monitoring device
410 1st LAN transmission / reception controller
420 Second LAN transmission / reception controller
500 monitors
600 measuring instruments
NW network
CPU processor
MEM memory
BUS Common bus
RCV_PCKT Receive packet
SND_PCKT transmission packet In the figure, the same reference numerals indicate the same or corresponding parts.

Claims (5)

A first step of receiving a packet from a network via a working port;
A second step of buffering the received packet;
A third step of stopping the buffering when detecting that a failure has occurred in the working port;
A fourth step of sending at least a predetermined range of packets buffered up to the time of the failure to an external device via a spare port;
A packet retransmission method comprising: In claim 1,
The third step includes a step of transmitting a failure notification to the external device together with the stop of the buffering,
The packet retransmission method, wherein the fourth step is executed based on a packet retransmission setting command generated from the external apparatus that has received the failure notification. In claim 2,
A packet retransmission method, wherein the packet retransmission setting command specifies the predetermined range. A first means for receiving a packet from a network via a working port;
A second means for buffering the received packet;
A third means for stopping the buffering when detecting that a failure has occurred in the working port;
A fourth means for sending at least a predetermined range of packets buffered up to the time of the failure to an external device via a spare port;
A packet retransmission apparatus comprising: In claim 4,
The third means includes means for transmitting a failure notification to the external device together with the stop of the buffering;
A packet retransmission apparatus, wherein the fourth means is executed based on a packet retransmission setting command generated from the external apparatus that has received the failure occurrence notification.

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