JP2003198432A - Active/standby switching control system and switching control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform active/standby switching in order not to drop or overlap data. <P>SOLUTION: In the active/standby switching control system and the switching control method provided with a high-order device 1, a low-order device 2 of a standby system and a single or a plurality of low-order devices 3 of an active system for switching the low-order devices 3 of the active system and the low- order device 2 of the standby system under control from the high-order device, the high-order device 1 is provided with a means for sending a switching instruction of the low-order device 2 of the standby system in response to the occurrence of an active/standby switching factor and a means for receiving a switching response containing a switching timing to the switching instruction from the low-order device 2 of the standby system and for sending this switching timing to the low-order device 3 of the active system to perform active/standby switching, and each of the low-order device 2 of the standby system and the low-order devices 3 of the active system is provided with a switching processing means for performing active/standby switching according to the switching timing. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active backup switching control system which has a single or a plurality of active system devices for a standby system device and switches to a standby system device when performance deterioration or failure of the active system device occurs. The present invention relates to a switching control method.

[0002]

2. Description of the Related Art FIG. 5 is an explanatory view of a conventional active standby switching control system, and shows an example of a switching system. FIG. 5A shows an upper device 50 and a lower device 51 of a standby system.
And a lower device 52 of the active system, the lower devices 51, 5
The reference numeral 2 has functions such as path setting and path switching according to call control information in the processor and the switching device, for example. An inter-system communication route 53 is formed between the standby system lower device 51 and the active system lower device 52. Then, a clock signal is supplied from the upper device 50 to the standby lower device 51 and the working lower device 52 to synchronize the devices.

Further, from the upper device 50 to the lower device 52 of the active system.
The call control information is sent to control the call connection.
At that time, the active lower device 52 is replaced by the standby lower device 5.
The call control information from the higher-level device 50 is transferred to the No. 1 via the inter-system communication route 53. The backup lower device 51 is
It holds this call control information. Thereby, the host device 50
When there is an instruction to switch the active spare from the standby system, the lower device 5 of the standby system
1 can continue the call control by taking over the control state of the active lower device 52 based on the held call control information.

FIG. 5B includes an upper device 60, a backup lower device 61, and an active lower device 62.
By omitting the inter-system communication route, the host device 6
From 0, the call control information to be sent to the active lower device 62 is also sent to the standby lower device 61. Then, the lower system 61 of the standby system holds the call control information and can take over the call control state of the lower system 62 of the active system by the switching instruction from the upper system 60 to operate as the active system.

In the case of an N: 1 active standby switching control system in which one standby lower device is provided for N active lower devices, N backup standby devices are provided for each N standby device. The system configuration shown in FIG. 5B is applied because the system configuration is complicated to form the inter-system communication route with the active device. The backup lower device is N
A function for holding call control information and the like for each of the active lower devices is provided for each active lower device.

FIG. 6 is an explanatory view of a switching control operation sequence of a conventional example, showing a configuration corresponding to a higher-order base station control station of a plurality of base stations of a mobile communication system, and CONT controls each unit according to a call control request or the like. Upper control device, C
OM indicates a switching control device that gives a call setting control instruction of a lower device according to an instruction from the upper control device CONT,
The upper control device CONT and the switching control device COM are
This corresponds to the higher-level devices 50 and 60 in FIGS. 5A and 5B.

DHT0, DHT1, and DHT2 are lower-level connecting devices for connecting highway ports, in which case the connecting device DHT0 is the standby system (SBY) and the connecting devices DHT1, DHT2 are the active system (ACT). Then, a case where a 2: 1 active spare switching control system in which one spare connection device DHT0 is provided for two active connection devices DHT1 and DHT2 is configured.

The upper control device CONT sends a control instruction to the switching control device COM according to a request from a user (not shown) or another switching device. For example, when the connection setting 1 is sent, the switching control device COM.
Is the active connection device DHT1 and the standby connection device DH
This connection setting 1 is sent to T0. The active connection device DHT1 connects to, for example, the highway (HW) port 1 according to the instruction of the connection setting 1. Further, the spare connection device DHT0 holds the information of the connection setting 1 and sets the highway (HW) boat to the unconnected state. In this case, which corresponds to the control configuration shown in FIG. 5B, the same control instruction is sent from the host device to the active system device and the standby system device.

Next, when the upper controller CONT sends the connection setting 2 to the switching controller COM, the switching controller COM sends the connection setting 2 to the active connection device DHT2 and the standby connection device DHT0. .
The active connection device DHT2 uses this connection setting 2
According to the instruction of, for example, the highway port 2 is connected, the spare connection device DHT0 holds the information of this connection setting 2, and the highway port is left unconnected.

In such a control state, when the host controller CONT sends a blockage instruction of the active connection device DHT1 to the switching control device COM according to the abnormality detection information of the active connection device DHT1 and the like, the switching control is performed. Device COM
Sends a switching instruction to the spare connection device DHT0.
The spare connection device DHT0 uses the hardware (HARD) to store the information of the connection setting 1 held according to the switching instruction.
Setting and preparation for switching are performed, and a switching response indicating completion of the preparation is sent to the switching control device COM.

The switching control device COM responds to the switching response from the connection device DHT0 of the standby system by the switching device COM of the active system.
The T1 is instructed to change the allocation of the highway port, and then the standby connection device DHT0 is instructed to switch to the active system. As a result, the spare connection device DHT0 connects the highway port 1 according to the connection setting 1 and operates as the active system (ACT). Further, the connection device DHT1 which was the active system is in a state of being disconnected from the highway side as indicated by BLK.

When the state of the connection device DHT1 which was the active system before is restored, the upper control device CONT sends a blockage release instruction of the connection device DHT1 to the switching control device COM. The switching control device COM sends a switchback instruction to the connection device DHT0 in accordance with this blockage release instruction. The connection device DHT0 releases the hardware setting of the connection setting 1 and sends a response of the operation according to the instruction to the switching control device COM. Then, the switching control device COM is connected to the connection device DH.
The T0 is instructed to change the highway port allocation, and then the connection device DHT1 is also instructed to change the highway port allocation. As a result, the connection device DHT1 returns to the active system (ACT), and the connection device DHT0 returns to the standby system (SB).
I will return to T).

[0013]

In the above-described conventional active standby switching control, when the active connection device DHT1 is switched to the standby connection device DHT0, the unconnected state of the highway port during the hatched period is as follows. In the case of occurrence and switching back, the unconnected state of the highway port occurs during the period shown by the diagonal lines. If such an unconnected state occurs, there is a problem that user data is lost in the process of switching the working protection.

Therefore, it is conceivable to connect the same highway to the highway ports of the active-system connecting device and the standby-system connecting device. In that case, the active-system connecting device and the standby-system connecting device are simultaneously connected. There is a problem that duplicate data flows through the device and data errors increase due to a slight timing shift. An object of the present invention is to make it possible to switch the working spare without missing data and without duplication.

[0015]

The active standby switching control system of the present invention will be described with reference to FIG.
And a standby lower device 2 and a single or a plurality of active lower devices 3, and switching between the active lower device 3 and the standby lower device 2 under the control of the higher device 1. In the active standby switching control system, the upper device 1 sends a switching instruction to the lower device 2 of the standby system when a switching factor of the active backup occurs, and responds to the switching instruction from the lower device 2 of the standby system. And a means for receiving a switching response including the switching timing and transmitting the switching timing to the lower apparatus 3 of the working system which performs the switching of the working spare, and the lower apparatus 2 of the protection system and the lower apparatus 3 of the working system. Has a switching processing means for switching the active spare according to the switching timing.

Further, the higher-level device 1 notifies the lower-level devices 2 and 3 of the active system and the standby system of the frame number synchronized with the clock signal, and switches the switching timing between the active and standby based on this frame number. It is provided with means for notifying the lower apparatus 3 of the active system. In addition, the sub-devices of the active system and the standby system 2,
3 has a data matching block for temporarily storing received data and an output control block for sending data from this data matching block. The timing at which the data received and accumulated in the data matching blocks of the lower devices 2 and 3 are matched is set as the switching timing, and at this switching timing, the output control block of the active lower device 3 is closed and the standby lower device 2 Means may be provided for controlling the opening of the output control block.

The switching control method of the present invention is also applicable to the host device 1.
And a standby lower device 2 and a single or a plurality of active lower devices 3, and switching between the active lower device 3 and the standby lower device 2 under the control of the higher device 1. In the switching control method, the higher-level device 1 sends a switching instruction to the lower-level device 2 in the standby system when a switching factor for the current standby is generated, and the lower-level device 2 in the standby system receives the switching instruction.
A switching response including the switching timing is sent to the host device 1,
The higher-level device 1 notifies the lower-level device 3 of the active system, which performs the switching of the current-use spare, of the switching timing. This includes the process of switching.

Further, the higher-level device 1 notifies the lower-level devices 2 and 3 of the active system and the standby system of the frame number synchronized with the clock signal, and in accordance with the switching instruction from the higher-level device 1, the lower-level device 2 of the standby system. The switching timing based on the frame number from 1 to 5 is transmitted to the higher-level device 1, and the higher-level device 1 can include a process of notifying the switching timing to the lower-level device 3 of the active system, which switches the active protection.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram for explaining the principle of the present invention. Reference numeral 1 is a higher-level device, 2 and 3 are lower-level devices, and the lower-level devices 2 and 3 are equivalent to connection devices that perform highway connection control. To do. The lower device 2 shows the case of the standby system (SBY), and the lower device 3 shows the case of the active system (ACT). Therefore, the active lower device 3 turns on the highway port, and the standby lower device 2 turns off the port. Although the case of the 1: 1 active spare switching control system is shown, it is also possible to configure an N: 1 active spare switching control system.

The higher-level device 1 sends a switching instruction to the lower-level device 2 in the standby system when a switching factor for the active spare is generated, and a switching response including a switching timing in response to the switching instruction from the lower-level device 2 in the standby system. Is received and the switching timing is transmitted to the lower apparatus 3 of the active system for switching the active spare. Further, the backup system lower-level device 2 and the working system lower-level device 3 have switching processing means for switching the working standby mode at the same switching timing.

Further, the clock signal CLK is supplied from the upper device 1 to the lower devices 2 and 3 to enable synchronization between the respective devices, and further, in synchronization with the clock signal CLK, for example, a frame having a cycle of 10 ms. Is sent from the upper device 1 to the lower devices 2 and 3. Further, when control information such as connection setting information is sent from the upper device 1 to the active lower device 3, the same control information is also sent to the standby lower device 2. The subordinate device 2 of the standby system holds this control information.

If the time required from the reception of the instruction for switching the working spare from the upper apparatus 1 to the actual switching of the working spare is α, the upper apparatus 1 is the lower apparatus 3 of the working system.
The switching instruction is issued to the lower device 2 of the backup system according to the abnormality detection information such as the error rate deterioration in the above. The backup lower device 2 is
Since the switching can be completed as the active system at the time t + α from the timing t of this switching instruction, the host device 1 responds with this as the switching timing.

The upper device 1 notifies the lower device 3 of the active system of the switching timing for switching to the standby system at the timing of t + α. As a result, the lower devices 2 and 3 are t + α.
It is possible to switch on / off of the highway port at the same time at the switching timing, and shift from the active system to the standby system or from the standby system to the active system. As a result, it is possible to switch the active spare so that the user data transmitted via the highway is not lost or duplicated.

FIG. 2 is an explanatory view of the embodiment of the present invention, in which 11 is a higher-level control device (CONT), 12 is an ATM switch (ATMSW), and 13 is a switching control device (CO).
M), 14 are highway selective connection devices (HWS), 1
5, 16 and 17 are connection devices (DHT) corresponding to lower devices.
0, DHT1, DHT2), 21 is a control processing unit, 22 is a timing control unit, 24 is a 2-port selection unit, and 25, 2
Reference numerals 6 and 27 denote switching processing units.

This embodiment shows a case corresponding to an upper base station control station of a plurality of base stations in a mobile communication system, and an ATM is provided between the upper control device 11 and the switching control device 13 and a highway. It is transmitted by the cell, A
The TM switch 12 performs route control based on the virtual path identifier (VPI) and virtual channel identifier (VCI) of the header of this ATM cell. In the U plane route, user data is stored in the payload. AT
M cells are transmitted, and ATM is used in the C plane route.
Various control information is set in the payload of the cell and transmitted. The other device connected to the ATM switch 12 is a device such as a base station or a mobile switching center.

Further, in the N: 1 active spare switching system in which one spare connection device is provided for N active connection devices, the case where N = 2 is shown. Therefore, the highway selecting / connecting device 14 controls switching between the three highways between the three connecting devices shown as the U-plane route and the two highways on the other device side connected via the ATM switch 12. The two-port selection unit 24 has a configuration for selectively connecting under the control of the device 13. Further, the host controller 11 and the switching controller 13 correspond to the host device 1 in FIG. 1, and the connecting devices 15, 16 and 17 correspond to those in FIG.
Corresponding to the lower-level devices 2 and 3 in the above, for example, a process such as a handover due to a mobile station moving between a plurality of base stations as other devices is transferred to the active-side connection device by a command from the upper-level control device 11. It can be executed by switching virtual channels.

Further, the switching control device 13 is provided with means including a control processing part 21 and a timing control part 22, and the connection devices 15, 16 are connected via a route shown as a C plane route.
Transmission processing of control information and the like is performed with the digital camera 17.
In this case, the FN is synchronized with the clock signal, for example, 1
The frame number of 0 ms cycle is shown. That is, a clock signal is supplied from the switching control device 13 to the connection devices 15, 16 and 17 to enable the synchronous operation, and the time information is notified by the frame number FN.

Further, a state is shown in which the connection device 15 is the standby system (SBY), the highway reception port is in the off state, the connection devices 16 and 17 are the active system (ACT), and the highway reception port is in the on state. Switching processing unit 2
Reference numerals 5, 26 and 27 have a function of controlling the switching of the working spare by turning on and off the highway port in accordance with the switching command from the switching control device 13.

Therefore, the means for sending the switching instruction to the lower system of the backup system is the control processing unit 2 of the switching control device 13.
The function corresponding to the function No. 1 and transmitting the switching timing to the lower device of the active system corresponds to the function including the function of the timing control unit 22. In addition, the active spare switching processing means of the lower device is the switching processing unit 25, 2 of the connection device 15, 16, 17.
6 and 27 functions.

FIG. 3 is an explanatory view of the switching control operation sequence according to the embodiment of the present invention, in which the upper control device (CONT) 1
1, a switching control device (COM) 13, a connection device (DH)
T0, DHT1, DHT2) 15, 16 and 17 are represented by abbreviations, and the connecting device DHT0 is a standby system (SBY),
The state where the connection devices DHT1 and DHT2 are set to the active system (ACT) is shown.

Therefore, as in the conventional example, the host controller C
Connection setting 1 from ONT as A as ATM cell
When it is sent to the switching control device COM via the TM switch 12 (ATMSW), the switching control device COM sends the connection setting 1 to the connection device DHT1. in this case,
When the control processing unit 21 of the switching control device COM processes the connection setting 1 from the higher-level control device CONT by the control processing unit 21 and determines that it is for the connection device DHT1,
Active system connection device DHT1 and standby system connection device DHT
The connection setting 1 is sent to 0.

The active connection device DHT1 controls the highway port connection based on the connection setting 1 by the switching processing unit 26 by virtual channel setting or the like, and connects the highway port 1, for example. In addition, the spare connection device D
HT0 is connected device DH by the processing of the switching processing unit 25.
Only by holding the connection setting 1 corresponding to T1, the highway port continues to be in the unconnected state. That is, the spare connection device DHT0 stores connection setting information or the like for the active connection device sent from the switching control device 13 in correspondence with the connection device by a storage means (not shown).

Similarly, when the connection setting 2 is sent from the upper control device CONT, the control processing unit 21 of the switching control unit COM determines that it is for the active connection device DHT2, and determines that this connection device DHT2 and the standby system are connected. Connection device D
Connection setting 2 is sent to HT0. As a result, the active connection device DHT2 controls the highway port connection by the switching processing unit 27 based on the connection setting 2 by virtual channel setting or the like, and connects the highway port 2, for example. In addition, the spare connection device DHT0
Holds the connection setting 2 corresponding to the connection device DTH2 by the processing of the switching processing unit 25, and the highway port continues to be in the unconnected state. At this time, the highway selective connection device 14 selectively connects the two highways via the ATM switch 12 and the active connection devices DHT1 and DHT2.

In the above-mentioned connected state, the active connection devices DHT1 and DHT2 can transmit the received data via the highway as a predetermined virtual channel, as indicated by port-on. Then, based on the abnormality detection information of the connection device DHT1 of the active system, etc., the host controller C
When the ONT sends a blockage instruction for the connection device DHT1, the switching control device COM makes a determination by the control processing unit 21, and determines the connection device DHT0 for the standby system and the connection device D for the active system.
HT1 and a switching instruction (1 → 0; DHT1 to DHT0
(Indicating a switch to) is sent. Since the information indicating the connection device DHT1 is included in the switching instruction information, the switching processing unit 25 of the standby connection device DHT0 changes the connection setting 1 corresponding to the connection device DTH1 to the switching processing unit 25.
Set to hard.

Further, the switching control device COM controls the highway selection connection device 14 according to a sequence (not shown), and the active connection device DTH1 and the standby connection device D are connected.
Connect the highway for TH0 and at the same time. Even in this state, since the highway port of the connection device DHT0 of the standby system is in an unconnected state, duplicate data is not transmitted via both the connection devices of the active system and the standby system.

Next, the switching control device COM instructs the spare connection device DHT0 to change the allocation of the highway port. This connection device DHT0 has a switching processing unit 25.
Control of the highway port 1 is performed.
Then, the switching timing is notified to the switching control device COM. This switching timing is, for example, when the switching can be executed in the next frame cycle of the current frame number FN,
FN + 1 is notified as the switching timing. That is, the case where one frame period is set as the time α required for switching the above-mentioned active spares is shown.

The switching control device COM instructs the switching device FHT + 1 by the processing of the timing control section 22 to the active connection device DHT1. When the frame number in the switching processing unit 26 reaches the notified switching timing FN + 1, the connecting device DHT1 closes the highway port and sends a switching response to the switching control device COM. Also, in the switching processing unit 25 of the connection device DHT0 of the standby system, the notified switching timing FN + 1
At this time, the highway port is turned on and a switching response is sent to the switching control device COM. That is, since the active connection device DHT1 and the standby connection device DHT0 can switch highway ports at the same switching timing, data loss does not occur.

Further, the switching control device COM controls the highway selection connection device 14 by a sequence not shown, and controls the highway selection connection device 14 so as to connect to the connection device DHT0 switched to the active system. Therefore,
The connection devices DHT0 and DTH2 are in a state of operating as an active system.

When the connection device DHT1 is restored to the normal state, the upper control device CONT sends a blockage release instruction for the connection device DHT1. The switching control device COM instructs the connection devices DHT0 and DHT1 to switch (0 → 1; DHT0
To DHT1), and controls the 2-port selection unit 24 of the highway selection connection device 14 to connect the highways to the connection devices DHT0 and DHT1 at the same time. In this case, since the port of the connection device DHT0 is in the off state, even if the highway is connected, duplicated data will not be transmitted. Further, the switching processing unit 25 of the connection device DHT0 determines a switching instruction to the connection device DHT1. The connection setting 1 is released and the information of the connection setting 1 is held. Also, the switching control device COM sends a switching instruction to the connection device DHT1.

The connection device DHT1 notifies the switching control device COM of the switching timing by the switching instruction. As for the switching timing, as in the case described above, the time α required for switching is added to the current frame number FN and transmitted. Also in this case, if α = 1, the switching timing is FN.
It becomes +1. Timing control unit 2 of switching control device COM
2 refers to this switching timing FN + 1 as the connection device DHT0.
To notify. Thereby, the connection device DHT0 closes the highway port at the switching timing FN + 1 and discloses the setting of the connection setting 1. Further, at the switching timing FN + 1, the connection device DHT1 can switch back the active spare at the same switching timing FN + 1 by opening the highway port.

Then, the connection devices DHT0 and DHT1 each send a switching response to the switching control device COM. As a result, the switching control device COM is connected to the connection device DH.
Instruct T0 to change the highway port allocation. In addition, the two-port selection unit 24 of the highway selection connection device 14 is controlled by a sequence (not shown) to cut off the highway connection to the connection device DHT0. As a result, the initial control state is restored.

FIG. 4 is an explanatory view of the switching control process according to the embodiment of the present invention, and the spare connection device 15 in FIG.
The active connection device 16, the input / output side 14a and 14b of the highway selection connection device 14, and the switching control device 13 are shown. The connection devices 15 and 16 include a data matching block such as a memory and an output control block such as a gate, and the highway selection connection devices 14a and 14b.
Includes a route selection block for switching connection to the highway. This route selection block corresponds to the function of the 2-port selection unit 24 in FIG.

In FIG. 4A, the highway selection connection device 14a, 14b is connected to the active connection device 16 via the route selection block, and the highway selection connection device 14 is connected.
The data through the route selection block of a is connected to the connection device 16
Is sent to the route selection block of the highway selection connection device 14b via the data matching block on the reception port side and the output control block on the transmission port side. in this case,
The standby-system connecting device 15 is in a disconnected state.

When the above-mentioned switching instruction is sent from the switching control device COM, the highway selection connection device 14a is controlled by the switching control device COM as shown in FIG. Also connect the highway to. At this time, no connection is made with the highway selection connection device 14b. That is, since the output control block of the spare connection device 15 continues to be closed, the data received in the data matching block is not sent to the highway selection connection device 14b.

When the data matching block of the connection device 16 of the active system and the data matching block of the connection device 15 of the standby system are in a state of being matched with each other, that is, the time α required for switching the active spare is set. Then, as shown in FIG. 4C, the output control block of the active connection device 16 is closed and the output control block of the standby connection device 15 is opened. Thereby, the highway selection connection device 1
The connection device 15 is connected between 4a and 14b. That is, the active spare is switched.

The present invention is not limited to the above-mentioned embodiment but can be variously added and modified. For example, not only the configuration of the base station controller but also other 1: 1 or It can be applied to an N: 1 working standby switching control system. The switching timing is frame number FN.
However, if the switching timing is synchronized with the clock signal, the timing information other than the frame number FN can be used.

[0047]

As described above, the present invention is 1: 1.
Or, an N: 1 active backup switching control system is configured, and when a switching factor for the active backup occurs, a switching instruction is sent from the upper device to the lower device of the standby system, and the lower device of the standby system uses the active standby to the upper device. The upper device notifies the switching timing to the lower device of the active system by simultaneously switching the lower device of the standby system to the active system and the lower device of the active system to the standby system. However, there is an advantage that the active spare can be switched without data loss and data duplication.

[Brief description of drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is an explanatory diagram of an embodiment of the present invention.

FIG. 3 is an explanatory diagram of a switching control operation sequence according to the embodiment of this invention.

FIG. 4 is an explanatory diagram of a switching control operation process according to the embodiment of the present invention.

FIG. 5 is an explanatory diagram of a conventional backup switching control system of a conventional example.

FIG. 6 is an explanatory diagram of a switching control operation sequence of a conventional example.

[Explanation of symbols]

1 Upper device 2, 3 Lower device 11 Upper control device (CONT) 12 ATM switch (ATMSW) 13 Switching control device (COM) 14 Highway selection connection device (HWS) 15, 16, 17 Connection device (DHT0, DHT1, D)
HT2)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masayoshi Nakano             3-9-18 Shin-Yokohama, Kohoku Ward, Yokohama City, Kanagawa Prefecture             Fujitsu Communication System             Within Co., Ltd. (72) Inventor Yoshio Miura             3-9-18 Shin-Yokohama, Kohoku Ward, Yokohama City, Kanagawa Prefecture             Fujitsu Communication System             Within Co., Ltd. (72) Inventor Manabu Takahashi             3-9-18 Shin-Yokohama, Kohoku Ward, Yokohama City, Kanagawa Prefecture             Fujitsu Communication System             Within Co., Ltd. F-term (reference) 5K021 AA05 AA09 CC19 DD03 DD05                       DD08                 5K067 AA35 BB02 BB21 DD57 EE10                       EE16 FF20 HH21 KK11 LL05

Claims (5)

[Claims] 1. A lower device of the active system and a lower device of the standby system, which includes a higher device, a lower device of a spare system, and a single or a plurality of lower devices of the active system, under the control of the upper device. In the active standby switching control system for performing switching with the above, the higher-order device sends a switching instruction to the lower-level device of the standby system when a switching factor of the active spare is generated,
Means for receiving a switching response including a switching timing in response to the switching instruction from the lower device of the standby system, and sending the switching timing to a lower device of the active system for switching the active backup, 2. The active standby switching control system, wherein: the lower-level device and the active-level lower-level device have switching processing means for switching the active standby according to the switching timing. 2. The upper device notifies the lower devices of the working system and the protection system of a frame number synchronized with a clock signal, and based on the frame number, switches the switching timing between the working protection and the working protection. 2. The active backup switching control system according to claim 1, further comprising means for notifying a lower device of an active system to perform. 3. The lower devices of the active system and the standby system have a data matching block for temporarily storing received data and an output control block for sending data from the data matching block, and the upper device. The timing at which the data received and accumulated in the data matching blocks of the subordinate devices of the active system and the standby system are matched by the switching instruction from the device is defined as the switching timing, and the subordinate device of the active system at the switching timing. 2. The active standby switching control system according to claim 1, further comprising means for controlling to close the output control block of 1 and open the output control block of the lower device of the backup system. 4. A lower device of the active system and a lower device of the standby system, which includes a higher device, a lower device of a spare system, and a single or a plurality of lower devices of the active system, and is controlled by the upper device. In the switching control method for switching between the backup device and the backup device, the upper device sends a switching instruction to the lower device of the backup system when a switching factor of the working backup is generated, and the lower device of the backup system is sent by the switching instruction. Sends a switching response including a switching timing to the higher-level device, and the higher-level device notifies the lower-level device of the active system, which performs the switching of the active protection, of the switching timing, and the lower-level device of the standby system and the active device. The lower-level device of the system includes a process of performing switching of the working spare at the switching timing. 5. The higher-order device notifies the lower-order devices of the active system and the standby system of a frame number synchronized with a clock signal, and the lower-order device of the standby system follows the switching instruction from the higher-order device. The switching timing based on the frame number of
5. The switching control method according to claim 4, further comprising a step of notifying the switching timing to a lower apparatus of an active system which performs switching of an active spare.