JP2011019046A - Device and method for communication control, program, and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the effect of abnormal noise mixing on speech communication due to the disconnection or a packet loss of a call during communication caused by the discontinuity of frame numbers in the process of returning from a failed state to a normal operation state.SOLUTION: During restoring, during a failure of communication equipment for supplying a frame number from a master clock card to a slave clock card, from a clock self-running state to a normal operation state, the master clock card inherits a frame number generated by the slave clock card.

Description

  The present invention relates to a communication control device, a communication control method, a program, and a recording medium.

Various techniques related to communication control have been proposed (see, for example, Patent Documents 1 to 4).
The invention described in Patent Document 1 is an invention of a phase difference automatic adjustment system that performs inter-card phase synchronization that automatically adjusts the phase difference between an active system reference clock supply card and a standby system reference clock supply card. Phase synchronization is performed.

  According to the invention described in Patent Document 1, even when the active card and the standby card are switched, a data transmission / reception error does not occur in the communication device, and a stable reference clock can be supplied in the communication device. .

The invention disclosed in Patent Document 2 includes a bus arbitration block that outputs a bus use permission according to a master block and a slave block, and a stop control block that resumes the supply of an internal clock when a start request is made About.
In the invention described in Patent Document 2, the bus arbitration block holds the divided transfer control circuit that restores the stopped bus use permission when a response signal is given, and the internal clock when the supply of the internal clock is resumed. A response signal holding circuit for outputting the response signal to the division transfer control circuit.

  According to the invention described in Patent Document 2, it is possible to detect a response signal given while the internal clock is stopped, and to reduce the power consumption by stopping the internal clock in the sleep mode without causing the bus arbitration operation. It is said that both efficiency can be achieved.

  The invention described in Patent Document 3 is an invention related to a clock switching system. When a clock switching instruction is executed and a clock switching signal is generated, a clock is being transmitted while a clear signal and a clock switching signal are cleared to clear a predetermined circuit of the data processing device. Switch.

  According to the invention described in Patent Document 3, the logic uncertainty of the central processing unit is removed by switching the clock circuit during the transmission of the clear signal, and the desired operation can be performed without reconfiguring the system by the emergency control circuit. The clock circuit can be switched.

The invention described in Patent Document 4 relates to a loop type data transmission system configured by connecting a plurality of data transmission apparatuses serving as slave stations in a loop shape with a transmission line.
A data transmission apparatus serving as a master station includes a transmission frame format generation circuit, a frame number generation circuit, a master data reception data frame synchronization circuit, a reception data frame buffer memory circuit, and a signal insertion circuit.
A data transmission apparatus serving as a slave station has a reception data clock extraction circuit, a slave station reception data frame synchronization circuit, and a branch / insertion circuit.

  According to the invention described in Patent Document 4, data can be transmitted to a sub-channel number once every a plurality of frames regardless of updating the frame number after transmission delay correction in loop data transmission, and line multiplexing can be performed efficiently. The number can be increased.

Here, FIG. 5 is a conceptual diagram of a control method of the communication control apparatus related to the present invention.
This figure shows “in-device FN (frame number) supply operation during normal operation”. For FNs 105, 106, 109, and 110 for synchronizing the cards in the apparatus in the normal operation state, the #N (active system) master clock card 103 generates the primary FN 105 based on the external DCS clock 101. The #E (standby system) master clock card 104 generates the secondary FN 106 based on the external DCS clock 102. The #N (active system) master clock card 103 and the #E (standby system) master clock card 104 relay and supply the slave clock cards 107 and 108 to the subordinate cards 111 in the apparatus.

  The firmware and hardware of the subordinate card 111 are between the cards in the device and between the device and the terminal using the FN 109/110 supplied as the primary from either the #N slave clock card 107 or the #E slave clock card 108 as a reference time. Synchronization is achieved and frame control of communication control signals and data packets is realized.

JP 2004-229020 A JP 2007-52685 A Japanese Patent Publication No.57-1111715 Japanese Patent Publication No. 7-93631

FIG. 6 is an explanatory diagram for explaining the problem of the communication control apparatus related to the present invention.
This figure shows “in-device FN supply when #N master clock card fails”. When the #N master clock card 203 fails and the primary FN cannot be generated, the generation FN 206 of the #E master clock card 204 that has generated the secondary FN 206 in synchronization with the #N master clock card 203 takes over the primary.

The #N slave clock card 207 detects the stop of the FN supply from the #N master clock card 203, and continues the FN generation 209 that is continuous from before the supply stop based on the self-running clock 205 in the slave clock card 207.
The subordinate card 211 compares both the FNs 209 and 210 supplied from the #N slave clock card 207 (self-running FN generation) and the #E master clock card 203. The subordinate card 211 selects the FN 210 supplied from the #E master clock card 204 as a reference time because the FN 210 supplied from the #E master clock card 204 is primary.

FIG. 7 is an explanatory diagram for explaining the problem of the communication control apparatus related to the present invention. FIG. 8 is an explanatory diagram of FN supply in the apparatus when the master clock card is recovered by the communication control apparatus related to the present invention.
FIG. 7 shows “in-device FN supply when both master clock card systems fail”.
If both the #N master clock card 303 and the #E master clock card 304 fail, both the #N slave clock card 307 and the #E slave clock card 308 continue the FN generation 309 and 310 based on the free-running clocks 305 and 306. To do.
This continuation constitutes a backup function that does not stop the FN supply to the subordinate card 311.

However, from the state of the slave clock card free-running supply shown in FIG. 7 due to the failure of both master clock card systems, as shown in FIG. FN405 generation is possible.
When the #N master clock card 403 switches back to the operation state in which the primary FN 405 is distributed and supplied to the device, the master clock card 403 is subjected to card initialization at the time of failure recovery, and the slave clock card self-run generation FN value is set. I can't recognize.
By not being able to recognize this, the primary FN 405 distributed and supplied by the #N master clock card 403 starts from the initial value.

  Accordingly, the primary FN 409 supplied by the subordinate card 411 has no continuity between the self-running FN 410 generated by the #E slave clock card 408 and the primary FN 409 started to be supplied from the #N master clock card. For this reason, frame discard due to frame number discontinuity or a difference occurs between the hardware time and the firmware processing time in the subordinate card.

  As a result, erroneous processing of hardware firmware processing delays, abnormal sound or disconnection due to communication data concealment NG with the terminal, etc., disconnection of a call during communication or mixing of abnormal sound when returning to normal operation state, etc. There was an effect of the occurrence of the event.

  Therefore, an object of the present invention is a communication control device that prevents the influence of the disconnection of a call during communication due to discontinuity of frame numbers or the mixing of abnormal sounds into a call due to packet loss in the process of switching from a failure state to a normal operation state, A communication control method, a program, and a recording medium are provided.

  The apparatus of the present invention uses a master clock card that generates a frame number and a slave clock that uses a frame number from the master clock card when it is normal and uses a frame number that is generated based on a free-running clock when the master clock card fails And a controller that controls the master clock card to take over the frame number generated by the slave clock card when recovering from the clock free-running state at the time of failure to the normal operation state. Features.

  In the method of the present invention, the frame number generated by the slave clock card when the communication device that supplies the frame number from the master clock card to the slave clock card is restored from the clock self-running state at the time of failure to the normal operation state, The master clock card takes over.

  The program according to the present invention makes the frame number generated by the slave clock means function as a means that the master clock means takes over when the clock self-running state at the time of failure is restored to a normal operation state. .

  The recording medium of the present invention records the above program.

  According to the present invention, in the process of returning from a failure state to a normal operation state, it is possible to prevent an influence such as disconnection of a call during communication due to frame number discontinuity or mixing of abnormal sounds into a call due to packet loss.

It is a conceptual diagram which shows one Embodiment of the communication control apparatus which concerns on this invention. It is an example of the sequence diagram for demonstrating operation | movement of the communication control apparatus shown in FIG. It is a conceptual diagram which shows other embodiment of the communication control apparatus which concerns on this invention. It is a conceptual diagram which shows other embodiment of the communication control apparatus which concerns on this invention. It is a conceptual diagram of the control method of the communication control apparatus relevant to this invention. It is explanatory drawing for demonstrating the subject of the communication control apparatus relevant to this invention. It is explanatory drawing for demonstrating the subject of the communication control apparatus relevant to this invention. It is explanatory drawing of FN supply in an apparatus at the time of the master clock card recovery | restoration of the communication control apparatus relevant to this invention.

Embodiments according to the present invention will be described with reference to the drawings.
<Features of the invention>
The present invention relates to a frame number used for synchronization between cards in a communication control device such as an exchange or between a device and a terminal. In a normal operation state, a frame number is generated based on the external DCS clock. If the master clock card supplied to the device is unable to supply both the #N (active system) and #E (standby system) systems due to failure, the slave clock card will use the free-running clock. An in-device frame number is generated. From the slave free-running state supplied to the subordinate card, the failure of either one of the master clock cards of # N # E is recovered, the frame number can be generated, and the supply is resumed in the apparatus. In the process of switching back to the normal operation state, a mechanism is added in which the master clock card takes over the frame number of the slave clock card generation due to the effects of disconnection of communication calls due to discontinuity of frame numbers and mixing of abnormal sounds due to packet loss. By this mechanism, a means for enabling a switchback without affecting a call during communication is provided.

<Configuration>
FIG. 1 is a conceptual diagram showing an embodiment of a communication control apparatus according to the present invention.
This figure shows the state of FN synchronization in the device when the master clock card is recovered by the communication control device.
The communication control apparatus shown in FIG. 1 includes a plurality of master clock cards 702, a plurality of slave clock cards 703, a plurality of subordinate cards 704, and a control unit 701.

The master clock card 702 is control software 701 having a duplex configuration of #N (active system) and #E (standby system) that generates and adds FN 709 to a DCS (external clock input) 710 and supplies it to the apparatus. Hardware that can be controlled.
The #N and #E master clock cards 702 receive the FN synchronization input from the #N and #E slave clock cards 703, respectively. When there is an instruction 706 from the control software 701, the master clock card 702 can supply the FN 708 generated using the FN value input from the slave clock card 703 as a start value to the DCS clock pulse and supply it to the apparatus. .

The slave clock card 703 is hardware that can be controlled by the control software 701 that distributes and supplies the FN 709 supplied from the master clock card 702 to the subordinate cards in a normal operation state of the apparatus.
At the time of failure of the master clock card 702, based on the free-running clock in the card, the FN 709 added from the next value of the final value of the FN 709 previously supplied from the master clock card 702 is generated and distributed to the apparatus. .
In this embodiment, it is assumed that the slave clock card 703 can transmit the FN 708 to synchronize the master clock cards 702 of #N and #E, respectively, if there is an instruction from the control software 701.

  The firmware and hardware of the subordinate card 704 select the FN 709 input on the primary side that is supplied from the #N and #E slave clock cards 703. The firmware and hardware of the subordinate card 704 realizes communication control and data packet frame control by synchronizing the cards in the device and between the device and the terminal as the reference time.

  The control software 701 manages and monitors various states relating to clock supply, such as the state of the master clock card 702 and the slave clock card 703, the external clock input state of the DCS 710, and the like.

  The master clock card 702 recognizes the transition timing from the slave clock card 703 and the self-running supply state to the normal operation state of the external clock 710 input when both systems fail. When this transition trigger is recognized, the master clock card 702 can be instructed to receive FN synchronization input from the slave clock card 703, and the slave clock card 703 can be instructed to transmit FN synchronization output to the master clock card 702.

<Operation>
FIG. 2 is an example of a sequence diagram for explaining the operation of the communication control apparatus shown in FIG.
A control unit 801 having control software monitors a failure state of both the # N # E master clock cards 802 and a state relating to the in-device FN distribution supply. The failure recovery notification 807 from the control unit 801 and the master clock card 802 is detected. If the control unit 801 analyzes that the failure recovery notification 807 of the master clock card 802 of at least one system is from the FN supply state 806 by the free-running clock 805 of the slave clock card 803, the control unit 801 recognizes this as a transition trigger to the normal operation state 813 To do.

The control unit 801 detects the presence or absence of failure recovery of at least one master clock card 802 from the FN supply state 806 by the self-running clock 805 of the slave clock card when both systems of the master clock card 802 fail. When detecting that the transition to the normal operation 813 is possible, the control unit 801 issues an FN synchronization instruction 809 using the slave clock card 803 as a synchronization source to the master clock card 802 that has recovered from the failure. The control unit 801 issues an FN synchronization instruction 809 and also issues an FN synchronization instruction 808 to the slave clock card 803 with the master clock card 802 as a synchronization destination.
The slave clock card 803 also supplies the FN supplied to the subordinate card to the master clock card 802.

  The master clock card 802 starts the FN generation synchronization 810 by placing the latest FN obtained from the slave clock card 803 on the external clock generated by the external DCS clock 812. When synchronization is completed, a master clock card 803 synchronization completion notification 811 is sent to the slave clock card 802, and the master clock card 802 starts distributing and supplying the primary FN. The slave clock card 803 switches from the self-running state 806 to the normal operation state 813 that receives the FN supply from the master clock card.

<Program>
The communication control apparatus according to the present invention described above is realized by a program that causes a computer to execute processing. Examples of the computer include general-purpose computers such as personal computers and workstations, but the present invention is not limited to this. Therefore, as an example, a case where the present invention is realized by a program will be described below.

Computer
There is a program that causes the master clock means to take over the frame number generated by the slave clock means when the clock self-running state at the time of failure is restored to the normal operation state.

  Thus, the communication control apparatus according to the present invention can be realized anywhere as long as there is a computer environment capable of executing the program.

<Recording medium>
Such a program may be stored in a computer-readable recording medium.
Here, examples of the recording medium include a computer-readable recording medium such as a CD-ROM (Compact Disc Read Only Memory), a flexible disk (FD), a CD-R (CD Recordable), and a DVD (Digital Versatile Disk). , Flash memory, RAM (Random Access Memory), ROM (Read Only Memory), semiconductor memory such as FeRAM (ferroelectric memory), and HDD (Hard Disc Drive).

  The above-described embodiment shows an example of a preferred embodiment of the present invention, and the present invention is not limited thereto, and various modifications can be made without departing from the scope of the invention. is there.

<Other embodiments>
When the slave clock free-running FN supply state shown in FIG. 7 returns to the normal operation state in which at least one master clock card shown in FIG. 8 recovers and generates the primary FN, the processing state shown in FIG. To add.

FIG. 3 is a conceptual diagram showing another embodiment of the communication control apparatus according to the present invention.
FIG. 3 shows “in-device FN synchronization when the master clock card is recovered”.
As shown in the figure, the master clock card 503 recovered from the failure and initialized is a processing state in which the master clock card 503 synchronizes the FN start value with the self-running FN 505 generated by the slave clock card 507 as a synchronization source. Can be added.

FIG. 4 is a conceptual diagram showing another embodiment of the communication control apparatus according to the present invention.
By adding this processing state, it is possible to ensure the continuity of the FN value 605 that is started to be supplied into the apparatus, as in the case of “FN supply in the apparatus when the master clock card is recovered” shown in FIG. It is possible to eliminate influential events such as disconnection of a call during communication and mixing of abnormal sounds that could not be avoided when switching back to the operation state.

  A method of generating an FN based on DCS and synchronizing an in-device card is also used in a communication control device other than an exchange, and the present invention can be applied. Further, when the master clock card is a device that directly supplies FN to the subordinate card without going through the slave clock card, the FN generation of the master clock card based on the self-running clock of the subordinate card is used as the synchronization source. It is also possible to synchronize the generation.

<Effect>
As described above, according to the present embodiment, it is possible to switch back to a normal operation state from the state where both master clock card systems are out of order without being affected by disconnection of a call during communication or mixing of abnormal sounds.

<Differences between the patent document and the present invention>
The invention described in Patent Document 1 is a general prior art in the technical field of the present invention, and describes the synchronization of reference clocks across cards. The present invention is different in the object in that the continuity of the frame numbers is guaranteed even when the continuity of the reference clock is once lost with respect to the frame constructed on the reference clock.

  The invention described in Patent Document 2 adds a circuit that holds a reception signal from another block even when the own device (bus arbitration block or internal clock) is stopped, and after the own device resumes operation. By responding, continuity seen from other devices is guaranteed. In the present invention, even if the own device (the clock card generated by FN) stops, the continuity when viewed from the other device is guaranteed by drawing the frame number guaranteed by the other block after the operation is resumed. The purpose of Patent Document 2 is similar to that of the present invention, but the target devices and means are different.

The inventions described in Patent Documents 3 and 4 are general prior arts in the technical field of the present invention.
In the above, the inventions described in Patent Documents 1 to 4 are different from the present invention.

  The present invention can be used for a communication control device such as an exchange which performs intra-device frame synchronization by a frame number.

701, 801 Control unit 702, 802 Master clock card 703, 803 Slave clock card 704, 804 Subordinate card

Claims (7)

A master clock card that generates a frame number;
A slave clock card that uses a frame number from the master clock card when it is normal, and that uses a frame number generated based on a free-running clock when the master clock card fails,
And a control unit that controls the master clock card to take over the frame number generated by the slave clock card when the clock self-running state at the time of failure is restored to the normal operation state. Communication control device. The master clock card receives the frame number synchronization input from the slave clock card, and the frame number generated from the frame number input from the slave clock card as the start value in the DCS clock pulse of the external input according to an instruction from the control unit To the subordinate card in the loading device,
The slave clock card generates a frame number added from a value next to the final value of the frame number supplied from the master clock card based on the self-running clock when the master clock card fails. To distribute and supply
When the controller recognizes the transition timing from the slave clock card free-running supply state to the normal operation state of the external clock input when both master clock card system failures occur, the master clock card receives the frame number synchronization input from the slave clock card. 2. The communication control apparatus according to claim 1, wherein the slave clock card is instructed to transmit a frame number synchronous output to the master clock card.   The master clock card takes over the frame number generated by the slave clock card when the communication device that supplies the frame number from the master clock card to the slave clock card recovers from the clock free-running state at the time of failure to the normal operation state. A communication control method characterized by the above.   The handover is performed when the master clock card that has recovered from the failure can be transferred from the frame number supply state by the self-running clock of the slave clock card at the time of the failure of the master clock card to the normal operation by the failure recovery of at least one master clock card. A frame number synchronization instruction is issued to the clock card with the slave clock card as the synchronization source, and a frame number synchronization instruction is also issued to the slave clock card with the master clock card as the synchronization destination, and the slave clock card is supplied to the subordinate card. 4. The communication control method according to claim 3, wherein the frame number is also supplied to the master clock card.   The master clock card puts the latest frame number obtained from the slave clock card on the external clock generated by the external DCS clock to start synchronization of frame number generation. When the synchronization is completed, the master clock card sends the master clock card to the slave clock card. A synchronization completion notification is issued, the master clock card starts distributing and supplying the primary frame number, and the slave clock card switches from the self-running state to a normal operation state in which the frame number is supplied from the master clock card. The communication control method according to claim 4. Computer
A program that causes the master clock means to take over the frame number generated by the slave clock means when the clock self-running state at the time of failure is restored to the normal operation state.   A recording medium on which the program according to claim 6 is recorded.

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