JP2010068547A - Detour constructing method for dual loop transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To produce a logical transmission trouble on an opposite loop transmission line, construct a detour circuit between loops and shorten a detour route length when a trouble occurs at only one place on the loop transmission line in a dual loop transmission system. <P>SOLUTION: The detour constructing method provides for a dual loop transmission composed of two loop transmission lines 1, 2 which perform data transmission in opposite directions with each other, NCP 11 to 18, and 21 to 28 that are formed in pairs on the transmission line, and detour circuits 31 to 38 that perform data transmission in two-way directions between the NCPs of each pair. When a trouble A1 is present at only one place on the loop transmission line, the NCP 17 constituting the detour circuit 37 stops a transmission function of the corresponding NCP 27, so that the transmission trouble place and the pair of transmission lines are logically cut to shorten the detour line length. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a detour configuration method in the case of a single loop failure on a loop transmission line in a double loop transmission system with detour.

  A detour configuration method for configuring a detour in loop transmission involving detours has been proposed previously. In the proposed detour configuration method, each transmission control device (Network Control) ensures that a message is transmitted to the host control device (hereinafter abbreviated as “host”) when there is only one failure on the loop transmission path. A detour is configured to transmit a message via Processor (hereinafter abbreviated as NCP) (NCP or NCP) (see, for example, Patent Document 1).

  The loop transmission detour configuration method will be described in detail below. FIG. 1 is a diagram for explaining the configuration of a loop-shaped loop transmission system, which has a loop 1 for transmitting a message clockwise and a loop 2 for transmitting a message counterclockwise. Further, NCPs 11 to 18 are connected to the loop 1, and NCPs 21 to 28 paired with the NCPs 11 to 18 are connected to the loop 2, respectively. The paired NCPs have detour transmission paths 31 to 38 that can transmit data in both directions, respectively, and the hosts 61 to 68 that perform message exchange are the transmission paths 41 to 48 and the transmission paths 51 to 51, respectively. 58 connects.

  As shown in FIG. 2, when Loop 1, Loop 2, and each NCP are in a normal state, the loop 1 transmission line between the host 67 and the host 68 is disconnected (disconnection A1), and transmission is impossible. Shall be.

  If a message is transmitted from the host 61 to the loop 1 via the NCP 11 in this state, the message is not returned to the originating NCP 11 due to the disconnection A1. For this reason, the NCP 11 detects that there is an abnormality on the loop 1 transmission path, transmits itself as a transmission source, transmits the small loop check data 100, and further requests the NCP 21 to transmit the small loop check data 200. .

  The NCP 12 that has received the small loop check data 100 from the NCP 11 transmits the small loop check data 100 to the NCP 22 and transmits the small loop check data 101 as a transmission source. In this way, the small loop check data 102 to 105 of the loop 1 are sequentially transmitted to the downstream NCP. When the small loop check data 105 reaches the NCP 17, the NCP 17 itself becomes a transmission source and transmits the small loop check data 106 in the same manner as the NCP 12, but the small loop check data 106 is returned to the transmission NCP 17 by the disconnection A1. Therefore, the NCP 17 satisfies one condition constituting a detour. Then, the NCP 17 further becomes the transmission source and transmits the large loop check data 300. However, the large loop check data 300 is not returned to the transmission source NCP 17 due to the disconnection A1, so that the detour configuration condition is satisfied and the NCP 27 is established. Thus, the detour path 37 is configured.

  In the loop 2, the NCP 28 similarly becomes the transmission source and transmits the small loop check data 201. However, since the small loop check data 201 is not fed back, one condition constituting the detour is satisfied. Then, the NCP 28 becomes a transmission source and further transmits the large loop check data 400. In the loop 2, the detour configuration condition is not satisfied when the large loop check data 400 returns normally, and the detour configuration is not performed.

  Thereafter, as shown in FIG. 3, the message 500 from the NCP 11 passes through the loop 1 in the transmission direction of the NCP 12 and NCP 13 and reaches the NCP 17, and then moves to the loop 2 through the detour 37. Reaches looper NCP21 through loop 2. Since there is an NCP that has not yet passed through the NCP in the loop 2, the loop 2 is made another round and returned to the source NCP pair NCP 21.

  In this way, the message 500 sent by the NCP 11 has a longer loop transmission path, and particularly when the NCP that is the last loop when viewed from the source NCP fails, the loop transmission path becomes longer and there is no detour. The loop transmission time is tripled and the round-trip feedback time of the loop transmission is increased.

JP-A-57-52249

  According to the present invention, when there is a failure at only one location on a loop transmission line of a double loop transmission system, the detour configuration method shortens a redundant loop transmission line and shortens a loop feedback round trip time. For the purpose.

  In order to solve the above-described problem, the present invention provides an NCP transmission function that is paired with an NCP that constitutes a detour when there is a failure at only one location on the loop transmission path in a double loop transmission involving a detour. To stop. In other words, a transmission path that is paired with a transmission path that has failed at only one location on the loop transmission path is set to a logically disconnected state (the loop transmission path is disconnected from both ends) to form a new detour.

  That is, the present invention provides two loop transmission lines that perform data transmission in opposite directions, an NCP that is provided as a pair on the transmission line, and a detour that performs bidirectional data transmission between each pair of NCPs. In the detour configuration method of the double loop transmission configured from the path, when there is only one failure on the loop transmission path, the NCP configuring the detour stops the transmission function of the paired NCP, The transmission path paired with the transmission failure location is logically disconnected to shorten the detour path length.

  According to the present invention, in the detour configuration method described above, the NCP that has detected that a failure has occurred on one loop transmission path transmits small loop check data to the adjacent NCP, and receives the small loop check data. NCP sends small loop check data sequentially to NCP downstream of loop, and NCP that could not receive small loop check data issued by itself sends large loop check data downstream of loop and cannot receive large loop check data When the counter NCP receives a small check data and a large loop data from the upstream, a setting is made so that transmission to the bypass or the loop downstream is rejected. Therefore, the loop transmission path paired with the transmission failure location is logically disconnected.

  Further, according to the present invention, in the above detour configuration method, when there is only one failure on the loop transmission line, the NCP configuring the detour stops the transmission function of the paired NCP, In the configuration in which the paired transmission line is logically disconnected, when the fault on the loop transmission line is recovered, the logically disconnected transmission line is released.

  Furthermore, the present invention provides the detour configuration method as described above, wherein a loop configuration state table is provided in the host connected to the NCP and the pair NCP, and includes a small loop check result, a large loop check result, a detour state, and a NCP transmission rejection request. The loop configuration state was memorized.

  In other words, the present invention provides (1) a means for detecting a failure location on a loop transmission path and requesting a NCP transmission rejection request to a pair of NCPs in a host connected to an NCP that configures a detour. (2) When a message excluding small loop check data is received from a loop in an NCP for which a request to reject NCP transmission is set, a means for discarding the received message is provided, and (3) a self-originated small loop In the NCP to which the check data has returned, there is provided means for canceling the bypass of the own NCP and canceling the NCP transmission rejection request.

  As described above, according to the present invention, even if a failure occurs only at one location on the loop transmission path, the loop transmission path can be shortened while protecting the purpose of the message transmission by the host to each NCP (NCP or NCP). In addition, the round-trip feedback time for loop transmission can be shortened.

The block diagram explaining the structure of the transmission system of the double loop form which this invention presupposes. The figure explaining the detour configuration procedure at the time of failure occurrence in the double loop transmission line which is the technical background of the present invention. The figure explaining the transmission path | route of the message at the time of performing the detour | route path | route structure in the double loop transmission path | route which is the technical background of this invention. The table format of the loop structure state in each host in the Example of this invention. The figure explaining the detour configuration procedure of the loop transmission line in the first embodiment of the present invention. The figure explaining the transmission path | route of the message at the time of performing the detour structure of the loop transmission path | route in 1st Example of this invention. The figure explaining the detour configuration cancellation | release procedure of the loop transmission path in 1st Example of this invention. The figure explaining the table state of the loop structure state until the detour structure cancellation | release of the loop transmission line in 2nd Example of this invention. The figure explaining the detour configuration cancellation | release procedure of the loop transmission line in 2nd Example of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 4 shows a loop configuration state table 1000 for storing the loop configuration state provided in the host connected to the double loop transmission system. Each of the hosts 61 to 68 has a loop configuration table, and uses an area corresponding to each of loop (loop transmission path) 1 and loop 2.

  The small loop check results 1001 and 1005 store whether or not the small loop check data has returned normally, and is set to “0” for OK and “1” for NG. The large loop check results 1002 and 1106 store whether or not the large loop check data has returned normally, and is set to “0” for OK and “1” for NG. The bypass states 1003 and 1007 store whether the current NCP bypass state is bypassing or not bypassing, and is set to “0” when not bypassing and to “1” when bypassing. The NCP transmission rejection requests 1004 and 1008 are requests that do not transmit the large loop check data and the result of the large loop check is NG, and are set to “0” in the case of a non-rejection request and “1” in the case of a rejection request. The In the case of the transmission rejection request, the NCP does not transmit the message received from the loop to the next adjacent NCP. However, other data is transmitted to the adjacent NCP or to the NCP regardless of the transmission rejection request.

  The outline of the first embodiment of the present invention will be described with reference to FIGS. FIG. 5 shows changes in the loop configuration state table 1000 of the hosts 67 and 68 until the logical disconnection. In FIG. 6, as in FIG. 2, it is assumed that the loop transmission between the host 67 and the host 68 is disconnected (disconnection A1) and transmission is impossible. If a message is transmitted from the host 61 to the loop via the NCP 11 in this state, the message is not returned to the NCP 11 as in FIG. Therefore, the host 61 itself becomes a transmission source and requests the small loop check 100 and the NCP 21 to transmit the small loop check data 200.

  Thereafter, as in FIG. 2, when the small loop check data circulates in the loop transmission direction and the small loop check data 106 transmitted from the NCP 17 is transmitted, it is not returned to the transmission NCP 17 due to the disconnection A1, and Since the large loop check data 300 from which the NCP 17 has been transmitted does not return to the NCP 17 due to the disconnection A 1, the NCP 17 constitutes a bypass 37.

  At this time, the host 67 sets the loop 1 small loop check result and the large loop check result of the loop configuration state table 1000 to (1: NG), sets the detour state (1: detouring), and requests to reject NCP transmission. (1: Rejection request) is set. (The states of FIGS. 5 and 1010) At this time, all items of the loop 2 of the loop configuration state table of the host 67 and the loop 1 and loop 2 of the loop configuration state table of the host 68 are all set to 0.

  By setting the state of 1010, the NCP 27 transitions to an operation of discarding the message transmitted from the NCP 28 when the NCP transmission rejection request is set.

  In the loop 2, as in FIG. 2, the NCP 28 becomes the transmission source and transmits the small loop check data 201. However, the small loop check data 201 is not returned due to the disconnection A1, and one condition constituting a detour is satisfied. Thereafter, the NCP 28 becomes a transmission source and transmits the large loop check data 400. However, since the NCP 27 is requesting rejection of transmission to the NCP, the large loop check data 400 is not returned. Therefore, the NCP 28 constitutes a bypass 38.

  Further, the host 68 sets the loop 2 small loop check result and the large loop check result of the loop configuration state table 1000 to (1: NG), sets the detour state (1: detouring), and requests to reject NCP transmission. (1: Rejection request) is set. (State of FIGS. 5 and 1011)

  After the NCP 17 and NCP 28 configure the detour path 37 and the detour path 38, as shown in FIG. 7, when the message 500 from the NCP 11 reaches the NCP 17 through the loop 1, it passes through the detour path 37 to the loop 2. This time, it passes through loop 2 and reaches the source NCP21. Further, it reaches the NCP 28 through the loop 2, moves to the loop 1 through the detour 38, and returns to the NCP 11 of the source NCP.

  In this way, when a failure occurs only at one location on the loop transmission, the NCP that configures the detour and the NCP that is adjacent to each other are configured at the same time. The loop transmission path is shortened, and the round trip feedback of the loop transmission is shortened.

  The outline of the second embodiment 2 of the present invention will be described with reference to FIGS. In this embodiment, a description will be given of the release of the detour configuration by the failure point recovery of the disconnection A1 when the detour configuration is performed by the detour configuration method of the first embodiment.

  FIG. 8 shows changes in the loop configuration state table 1000 of the host 67 and the host 78 when the detour is configured by the detour configuration method from the disconnected state.

  In FIG. 9, as in FIG. 6, it is assumed that the loop transmission between the host 67 and the host 68 is disconnected (disconnection A1) and transmission is impossible. In this state, the NCP 17 and the NCP 28 are configured as the detour 37 and the detour 38 according to the detour configuration method described in the first embodiment.

  In this state, the NCP 17 periodically transmits the small loop check data 106, but the small loop check data 106 is not fed back due to the disconnection A1.

  The NCP 28 also periodically transmits the small loop check data 201, but the small loop check data 201 is not fed back due to the disconnection A1.

  That is, the NCP 17 and the NCP 28 continue to form the detours 37 and 38. (State of FIGS. 8, 1012)

  When the disconnection A1 recovers from the failure from this state, the small loop check data 106 transmitted by the NCP 17 returns to the NCP 17 that is the transmission source, and the bypass 37 is released. At this time, the host 67 sets the small loop check result and the large loop check result of loop 1 in the loop configuration state table 1000 to (0: OK), sets the detour state (0: not detouring), and transmits to NCP. (0: Non-rejection request) is set in the rejection request. (State of FIGS. 8, 1013)

  Similarly, in the NCP 28, the small loop check data 201 transmitted by the NCP 28 returns to the NCP 28 that is the transmission source, and the detour path 38 is released.

  At this time, the small loop check result of loop 2 and the large loop check result of the loop configuration state table 1000 of the host 68 are set to (0: OK), and the detour state is set to (0: not detouring), and NCP transmission rejection is performed. Set (0: Non-rejection request) in the request. (State of FIGS. 8 and 1014)

  After the NCP 17 and NCP 28 have recovered the detour configuration, the message from the NCP 11 returns to the source NCP 11 through the loop 1 only.

  In this way, it is possible to detect the recovery of the location where the failure has occurred and cancel the configured detour.

1 Loop transmission line 1
2 Loop transmission line 2
11-18 NCP connected to loop transmission line 1
21 to 28 NCP connected to loop transmission line 2
31-38 Detour 41-48 NCP, Host-to-host transmission line 1
51-58 NCP, transmission path 2 between hosts
100 to 106 Small loop check data (Loop 1 direction)
200-201 Small loop check data (loop 2 direction)
300 Large loop check data (Loop 1 direction)
400 large loop check data (loop 2 direction)
500 Message 1000 Loop configuration status table 1001, 1005 Small loop check result 1002, 1006 Large loop check result 1003, 1007 Detour status 1004, 1008 Request to reject NCP transmission

Claims (4)

Two loop transmission lines that perform data transmission in opposite directions, a transmission control device (Network Control Processor: hereinafter abbreviated as NCP) provided in a pair with the transmission line, and bidirectional communication between each pair of NCPs In a double loop transmission detour configuration method comprising a detour that performs data transmission,
When there is only one failure on the loop transmission line, the NCP configuring the detour stops the transmission function of the large loop check data received from the paired NCP loop transmission line, and A detour configuration method characterized in that the transmission path is logically disconnected to shorten the detour path length.   2. The detour configuration method according to claim 1, wherein an NCP that has detected that a failure has occurred on one loop transmission line sends small loop check data to an adjacent NCP and receives the small loop check data. NCP sends small loop check data sequentially to NCP downstream of loop, and NCP that could not receive small loop check data issued by itself sends large loop check data downstream of loop and cannot receive large loop check data When the counter NCP receives a small check data and a large loop data from the upstream, a setting is made so that transmission to the bypass or the loop downstream is rejected. By means of this, the detour configuration method characterized in that the loop transmission path paired with the transmission failure location is logically disconnected.   3. The detour configuration method according to claim 1 or 2, wherein when there is only one failure on the loop transmission line, the NCP that configures the detour stops the transmission function of the paired NCP and causes a transmission failure. In a configuration in which a transmission line that is paired with a location is logically disconnected, when a fault on the loop transmission line is recovered, the logically disconnected transmission line is released.   4. The detour configuration method according to any one of claims 1 to 3, wherein a loop configuration state table is provided in a host connected to the NCP and a pair NCP, and a small loop check result, a large loop check result, and a detour state. A detour configuration method characterized by storing a loop configuration state consisting of a request to reject NCP transmission.

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