KR100608894B1 - TMD / IP data integrated delivery system and its network synchronization control method - Google Patents

Abstract

The present invention is based on the NG-SDH (Next Generation Synchronous Digital Hierarchy) optical transmission technology, enabling rapid switching to reduce the maximum packet network recovery time during switching due to a failure in the TDM / IP integrated data transmission network, and continuity of operation. The present invention relates to a TDM / IP integrated delivery system and a method for controlling the same synchronizer, which can provide a stable synchronization clock having a synchronous clock, wherein the single synchronizer selects one clock from a plurality of external synchronization sources and synchronizes the system with the selected clock. Implemented integrally in the switchboard implemented switchboard, and equipped with two switchboards as described above, operating a single switchboard, when a failure occurs in the manipulator, the switchboard that operates normally in the remaining standby mode Provides a synchronous clock by switching over and allowing stable active and standby operation It is designed to maintain the continuity of synchronization between systems within the network.

Transport network system, network synchronizer, switchboard, DOTS (Digital Office Time Supply), TDM (Time Division Mutiplexing), IP (Internet Packet)

Description

TDM / IP data convergence transmission system and its network synchronization control method {TDM / IP data convergence transfer system and network synchronization control method}

1 is a diagram illustrating a process of supplying a general synchronizer clock.

2 is a structural diagram of a TDM / IP integrated data transmission system to which the network synchronizer device according to the present invention is applied.

Figure 3 is a detailed configuration of the network synchronizer in the TDM / IP data integration delivery system according to the present invention.

4 is a data flow diagram between a switch fabric, a network synchronizer, and a controller in a network synchronizer according to the present invention.

5 is a flowchart showing the basic procedure of the network synchronizer control method according to the present invention.

Explanation of symbols on the main parts of the drawings

21: EMS / NMS (Element management system / Network managemnet system)

22, 23, 44: controller 24a, 24b, 43: switchboard

241, 242, 42: switch fabric 243, 244, 41: manipulator

25, 40: line card 141: reference clock selector

142: synchronous clock generation unit 143: system clock generation unit

144: reference clock interface unit 145: reference clock monitoring and control unit

The present invention relates to a TDM / IP (Time Division Multiplexing / Internet Packet) data integrated delivery system, and more particularly, to a network in which a TDM-based circuit switched network and an IP-based packet network are integrated and processed in a packet data form. The present invention relates to a TMD / IP integrated transmission system and a network synchronization control method capable of providing a clock synchronized with a link, and capable of fast switching on a TDM link and an IP link.

Recently, the information and communication environment requires a new service integrating data and circuit traffic, but the communication network up to now has a limit in meeting these requirements. As a communication network to be constructed in the future, a next generation network (hereinafter, referred to as NGN) or a next generation convergence network (hereinafter, referred to as NGcN) that can provide data services and voice services by integrating and providing them can be provided. The research on the TDM / IP data integration delivery system that integrates packet and circuit networks in the transport layer and guarantees quality of service (QoS) in the data delivery layer is being conducted. Here, the time division multiplexing (TDM) network is a data-oriented network, which is limited in supporting voice traffic, and the IP (Internet Packet) network supports voice traffic services in addition to data.

In addition, in a network constructed by integrating the world, it is necessary to maintain the same operation timing between domestic single stations and foreign single stations. To this end, digital devices constituting the network must be synchronized to one reference synchronization clock source. This reference synchronization clock is referred to as a network synchronizer clock.

In general, the network synchronizer clock uses the most stable clock among clocks received from a trunk interface or digital office timing supply (DOTS), and each digital device divides it to generate and use an internal system clock.

Figure 1 shows an example of the process of supplying the clock of the synchronizer, in the figure, 11 is a cesium oscillator, 12 is a system clock generator, 13, 14, 17, 18 is a digital clock supply device provided in a telephone station (Digital Office) Timing Supply, hereinafter referred to as DOTS), 15, 16, 19, and 20 represent external systems, respectively. The cesium oscillator 101 has a built-in GPS (Global Positioning System), and is a self-oscillator having excellent stability with an error rate of usually less than 10 ^-12 , the systems (15, 16, 19, 20) is the cesium oscillator (101) The E1 signal provided from the system clock generator 12 is transmitted through the DOTS 14, 13, 17, and 18 by using the synchronization signal outputted from the system. The system may be operated with a trunk matching device without DOTS.

The trunk refers to a large-capacity telephone channel installed between two telephone switching systems. The trunk can handle voice and data signals simultaneously due to its wide bandwidth. The trunk in digital communication also means a high-speed line.

Trunk matching synchronization means that the systems connected by such trunks transmit and receive information, and the reference clocks between the interworking systems must be identical.

In general, a network synchronizer device is implemented in a redundant structure to minimize synchronization deviation in case of a circuit failure or system failure. In a TDM / IP data transmission system that integrates a system TDM link and an IP link and processes them in the form of packet data, a network failure occurs. Must have fast recovery capability within a few tens of milliseconds.

In general, a synchronous optical network (SONET) / synchronous digital layer (SDH) network is a TDM-based circuit-switched network, the user can be assigned only a fixed bandwidth, such as Nx64K, T1, E1, T3, IP network, such as Ethernet Is a packet-switched network, which can be requested and allocated to various bandwidths desired by the user. Thus, a TDM link may have network recovery capability within 50 msec in case of a network failure, but the protocol used in the packet network is very complicated. Recovery in the service layer is difficult to satisfy within 1 second when the fiber cable is disconnected unless there is.

Therefore, when designing a TDM / IP integrated delivery system, research on the network synchronization problem in the packet network has been actively conducted.

The present invention has been proposed in order to solve the above-described problems, and its object is to provide fast switching to ensure the maximum packet network recovery time during switching due to a failure in the TDM / IP data transmission network. The present invention provides a TDM / IP integrated data delivery system and a method for controlling the network synchronizer capable of providing a stable synchronization clock with continuity.

As a construction means for achieving the above object of the present invention, the present invention comprises a plurality of line cards for inputting and outputting TDM and IP data through each channel; Each switch fabric determines a data transmission path between the plurality of line cards, and a reference clock is selected from an external DOTS signal and a plurality of input signals of the line card to generate and provide a system clock synchronized with the selected reference clock. A first and second switch boards having a network synchronizer to operate in a standby mode for waiting for the return of a fault and an operation mode for performing a switching function by performing a network synchronizer according to whether or not a trouble occurs in the network; And controlling the operation of each of the first and second switchboards, checking the failure state of each of the first and second switchboards, and switching the first and second controllers to the normally operable switchboard. Provided is a TDM / IP data delivery system.

In addition, in the TDM / IP integrated data transmission system according to the present invention, each of the network synchronization unit of the first and second switching board, the clock of the optical signal input through the DOTS clock signal or a plurality of line cards respectively received from the external DOTS A reference clock selecting unit which selects one of the signals as a reference clock according to the priority specified by the first and second controllers; A synchronization clock generation unit generating a clock synchronized with the reference clock selected by the reference clock selection unit; A system clock generation unit generating a system clock used for the corresponding system based on the clock output from the synchronization clock generation unit and providing the system clock to the corresponding switch fabric; A reference clock interface unit for receiving one reference clock received from the highest level selected by the reference clock selection unit and operating normally; After monitoring the failure of the link supplying the selected reference clock through the reference clock interface unit, reporting the failure to the corresponding first and second controllers, and controlling the network synchronizer to perform the switching and phase maintenance function, It is characterized by consisting of the reference clock monitoring and control unit for monitoring the faulted link to restore the network back to the fault recovery.

In addition, the TDM / IP data transfer system according to the present invention is connected to the switching fabric and the data and address bus corresponding to each network of the first and second switchboards, and is also physically connected to the corresponding first and second controllers. Directly connected to the signal line, the connection from the manipulator of the first and second switchboards to each of the first and second controllers is via the physical signal line, and the corresponding first and second switchboards from the first and second controllers. The connection to the network synchronizer is characterized in that it is made by IPC communication through the bus.

In addition, the TDM / IP integrated transmission system according to the present invention reports the corresponding network synchronizer to the corresponding first and second controllers through the physical signal line for a failure affecting the output of the reference clock. For failures that do not affect, it is configured to be reported to the upper part through IPC communication, so that when the network synchronization failure occurs, the network synchronizer and the switch fabric are almost simultaneously transferred by the controller.

In addition, in the TDM / IP data integrated delivery system according to the present invention, the physical signal line connecting the first and second controllers and the corresponding network synchronizer is a first signal line for failure indicating a failure of the network synchronizer. And a second signal line (status) for reporting the state of the network synchronizer and a reset third signal line (reset) for reporting whether or not the network synchronizer is reset.

In addition, the present invention is another configuration means for achieving the above object, TDM / IP data integration comprising two switchboards each consisting of a network unit and a switch fabric to perform a data exchange between a plurality of line cards in a redundant operation method A delivery system, comprising: applying initial power to a system; A setting step of setting the two switchboards into an operation mode or a standby mode, respectively, depending on whether the network synchronizer is disabled; Performing an operation mode of synchronizing the system by generating a system clock synchronized with the reference clock by receiving one reference clock from a preset external synchronization source; Performing the standby mode of synchronizing with the clock received from the network synchronizer of the other switchboard in normal operation; A monitoring step of monitoring a failure of a link providing a reference clock in a network synchronizer performing the operation mode; And performing a transfer by changing the switchboard of the failed network synchronizer unit to the standby mode according to the monitoring result, changing the switchboard of the standby mode to the operation mode, and then repeating the operation from the operation mode performing step according to the change. The present invention provides a method for controlling a synchronizer in a TDM / IP data transmission system.

In the method for controlling a network synchronizer of the present invention, the operation mode performing step may include: giving priority to a predetermined number of channels among a plurality of input channels of a plurality of line cards, respectively, to the network synchronizer; Setting whether to select a DOTS clock as an external synchronization source or a reference input clock signal of an optical signal input through the multiple line cards; If DOTS is selected as an external synchronization source, selecting and receiving one of DOTS clock signals applied from DOTS in the network synchronizer; When the reference clock signal of the optical signal is selected as an external synchronization source, receiving a reference clock signal from the selected channel according to the priority given by the network synchronizer; And generating a system clock synchronized with the clocks respectively input by the network synchronizer unit and providing the system clock to the line card through the switch fabric.

In the network synchronizer method of the present invention, the monitoring step includes: monitoring a failure of a link providing a reference clock in an operating network synchronizer unit; As a result of the monitoring, when a failure occurs, dividing the generated failure into a failure influencing the clock output and a failure influencing the network synchronization according to the extent; As a result of the classification, when the generated disability is urgently necessary, transmitting a fact of failure to a higher controller through a physical line; And, as a result of the classification, if the disabled caused to affect the network synchronization, characterized in that it comprises the step of transmitting through the IPC communication.

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration and operation of the network synchronizer method and apparatus of the TDM / IP data integrated delivery system according to the present invention.

2 is a block diagram showing a part of the TDM / IP data integration delivery system according to the present invention, wherein 21 is an operator management device, the operator is the element of the TDM / IP data integration delivery system EMS / NMS (Element Management system / Network management system) that can direct or monitor management and network management. In the present invention, the EMS / NMS 21 sets basic parameters for network synchronizer control such as instructing an operator to select which of the DOTS clock and the reference clock signal input from the optical signal for the network synchronizer.

22 and 23 are first and second controllers for controlling data transfer between a plurality of TDM links and IP links connected to a TDM / IP data integrated delivery system, and one side operates according to a failure state (hereinafter, active state). The remaining controllers wait to replace the synchronization processing when a failure occurs in the controller in the active state (hereinafter, referred to as a standby state). The first and second controllers 22 and 23 manage a series of processes of network synchronizer control including reference clock source switching for network synchronizer control.

Next, reference numeral 24 denotes a switching unit for performing connection and disconnection between the TDM link and the IP link by the first and second controllers 22 and 23, and for operation and / or two first and second switchboards ( 24a, 24b). Each of the first and second switchboards 24a and 24b is applied from first and second switching fabrics 241 and 242 which perform a switching function according to the control of the first and second controllers 22 and 23 and an external synchronization source. To the first and second network synchronizers 243 and 244 which synchronize the system with the clock signal and perform the conversion between the operation mode or the standby mode under the control of the first and second controllers 22 and 23 when the failure occurs. Is done.

Reference numeral 25 denotes a plurality of line cards each connected to a plurality of lines connected to a corresponding TDM / IP data integrated delivery system.

In the above description, the first and second network synchronizers 243 and 244 perform the same function, and receive DOTS clock signals DOTS1 and DOTS2 provided from an external DOTS (not shown) or through a plurality of line cards 25. After receiving a reference clock signal, one clock signal is selected under the control of the first and second controllers 22 and 23, and the corresponding system is synchronized with the selected clock. When a failure occurs, the operation mode is switched to the standby mode by itself or under the control of the first and second controllers 22 and 23.

In the above description, the first and second switchboards 24a and 24b may operate in an operation mode for performing a network synchronizer of the corresponding system and a standby mode for waiting for a failure of another switchboard.

In the above device, the switch fabric and the network synchronizer connected at the time of switching between the operation mode and the standby mode according to the failure should be switched at the same time.

In the present invention, in order to perform the switching at the same time, as described above, the manipulators 243 and 244 and the switch fabrics 241 and 242 are implemented on one board.

The first and second network synchronizers 243 and 244 perform the transfer at the same time as the corresponding first and second switch fabrics 241 and 242, so that the system can satisfy the specification requirements for line switching within 50 ms. do. The first and second network controllers 243 and 244 accommodate a reference clock through a plurality of line cards 25 and an operator uses the EMS / NMS 21 to control the first and second controllers in an interprocessor communication (IPC) communication method. The reference clock is selected through (22, 23). The first and second controllers 22 and 23 manage a series of processes including reference clock source switching.

The first and second manipulators 243 and 244 may be operated as a medium integrated with a controller as well as a switch fabric. However, in general, the switch fabric 244, 242 is connected to the quality of service (QoS) of the system, since the high-speed packet data of 160Gbit / s or more at a time of switching at a time, the first and second controllers (22, 23) The service of the system should not be affected even if the system is stopped due to a failure. In practice, the switching time of the controller is longer than that of the switch fabric side. In view of such an operation relationship, in the present invention, a structure in which the network synchronizers 243 and 244 depend on the switching operations of the switch fabrics 241 and 242 is selected as a preferred method.

As described above, the first and second network synchronizers 243 and 244 send the system clocks generated to be synchronized with the clock signal of the selected external synchronization source to the corresponding first and second switch fabrics 241 and 242. Send to 25 each. In addition, since each of the system clocks provided by the first and second network synchronizers 243 and 244 is input to each of the plurality of line cards 25, one of them is selected and used. At this time, it is preferable to select and use the clock of the network synchronizer 243 or 244 set for the work. As a result, the plurality of line cards 25 regenerate the signals synchronized with the selected clock, use them for various processing, and provide the first and second controllers 22 and 23 with signals necessary for maintenance and supervisory control.

3 shows a basic configuration of the first and second network synchronizers 243 and 244. The configuration is based on the first and second DOTS clock signals received from an external DOTS or a clock signal input through a line card 25. The reference clock selector 141 selects one of the reference clocks according to the priorities designated by the controllers 22 and 23, and generates a synchronous clock to generate a clock synchronized with the reference clock selected by the reference clock selector 141. A clock used for a system having frequency accuracy and stability for each level such as an international gateway or a domestic switching network (international switching center or city switching center) based on the clock generated from the synchronization clock generation unit 142 ( A system clock generator 143 for generating a TDM clock or an ATM clock) and a reference clock for receiving one reference clock that is normally operated from the highest level selected by the reference clock selector 141 and operates normally. Monitors whether the reference clock selected through the interface unit 144 and the reference clock interface unit 144 is faulty, controls to perform a switching and phase maintenance function in the event of a failure, and recovers the failed reference clock. It is composed of a reference clock monitoring and the control unit 145 to check the return to the reference clock when the failure recovery.

In the above, the synchronous clock generation unit 142 is fast, normal, hold-over, and free-running according to the reference clock monitoring and control of the control unit 145. It operates in four modes.

4 is a detailed diagram illustrating a signal transmission structure for a synchronizer between a line card, a synchronizer unit, a switch fabric, and a controller in the manipulator device according to the present invention, wherein the structure shown in FIG. Connection between the first controller 22, the first switch fabric 241, the first manipulator 243 and the connection structure between the second controller 23, the second switch fabric 242, the second manipulator 243 All apply.

Referring to FIG. 4, the network synchronizer unit 41 receives DOTS clock signals DOTS1 and DOTS2 from an external DOTS, and also includes a reference clock included in an optical signal input from each connected line from a plurality of line cards 40. Get input. In addition, a tip signal line, a ring signal line, and a selected network for transmitting an address bus, a data bus, and the DOTS signal between the network synchronizer 41 and the corresponding switch fabric 42 are selected. Signal lines (clk1 and clk2) to which the system clocks generated in synchronization with the synchronous clocks are transmitted are connected, and an address bus and a data bus are connected between the switch fabric 42 and the controller 44. And a control signal line (fail, status, reset) for transmitting status information (fail, status, reset information, etc.) of the network synchronizer 41 between the network synchronizer 41 and the controller 44. Is directly connected, allowing the controller 44 to directly manage and monitor the fault state or reset state of the network synchronizer 41.

The control structure as described above allows the network synchronizer 41 and the switch fabric 42 to share data by IPC (Interprocess communication) communication, thereby simultaneously synchronizing the network synchronizer 41, the switch fabric 42, and the controller 44. Enable transfer.

Therefore, in case of a failure in the network synchronizer 41 or the link providing the selected reference clock, the controller is immediately reported through a control signal line (fail status, reset) connected in hardware between the network synchronizer 41 and the controller 44. While monitoring the normal operation of the network synchronizer 41 at 44, it is possible to quickly reset the network synchronizer 41 in the event of a software failure or the like.

Therefore, when the switch fabric 42 is switched, the synchronizing unit 41 is also switched at the same time, and when the synchronizing unit 41 is first switched, the switching of the switch fabric 42 is made by the controller 44 at about the same time. As a result, the manipulator 41 and the switch fabric 42 can maintain a simultaneous operation state.

In the above, the fault of the synchronizer may be a fault that requires urgent action (for example, a fault that affects the clock output) and a fault that affects the synchronizer 41 (eg, PLL operation). And failures of external sources), and the processing varies depending on the type of failure. For example, when a fault requiring urgent action occurs, the network synchronizer 41 immediately transmits the fault occurrence to the controller 44 through the above-described physical signal line, and as a result, a rapid process is performed from the controller 44. It becomes possible. In addition, since other obstacles affecting the network synchronizer 41 may not affect the operation of the system immediately after occurrence, the presence or absence of an alarm and a failure through the periodic status inquiry of the network synchronizer 41 by the controller 44. The degree can be communicated and processed.

That is, the path through which the fault is transmitted from the network synchronizer 41 to the upper controller 44 may be immediately transmitted through the corresponding control signal line and may be transmitted through the data bus.

As described above, according to the present invention, the network synchronizer unit 41 is connected to the controller 44 by hardware or by means of a cable or a physical pattern, and the controller 44 is connected to the network unit 41 by the hardware. The connection is implemented in software by IPC communication through the switch fabric 42, so that when a failure occurs in the network unit 140, it has no effect on the system and can be quickly switched to maintain a stable network. .

As an example, in the data integrated delivery system as shown in FIG. 2, it is assumed that the first controller 22, the first switch fabric 241, and the first network synchronizer 243 are currently performing network synchronization of the system. At this time, when a failure occurs in the operating first network synchronizer 243, the information is transferred directly to the first controller 22 through the physical control signal lines (fast, status, reset) shown in FIG. Switching between the first network synchronizer 243 and the second network synchronizer 244 is logical. At this time, the transfer time is within about 20ms.

In addition, at the same time, the first controller 22 which has reported the failure performs the transfer between the first switch fabric 241 and the second switch fabric 242 at the same time as the transfer of the network synchronizers 243 and 244. Thereafter, the first controller 22 first checks whether or not the corresponding failure link has failed through the first switch fabric 241, and performs a failure processing through an internal path in software by IPC communication.

Next, the network synchronizer control method in the above-described network synchronizer device will be described.

5 is a flowchart illustrating a basic processing procedure for implementing a network device of the network device control method according to the present invention.

As shown in FIG. 5, when an initial power is applied to the corresponding system and operation starts (501), the controllers 241 and 242 are selected from a plurality of input channels per line card through an IPC bus (address bus, data bus). In operation 502, the first to fourth clock selection signals of priority are assigned to the four channels. In this case, the priority may be set by a SSM (Synchronization Status Message) signal provided by DOTS or arbitrarily set by an operator.

In addition, it is determined whether to select a DOTS clock or a reference input clock signal included in the optical signal input through the line card 25 as an external synchronization source (503). Here, the DOTS clock is a 2.048 MHz (E1) clock signal, and the reference input clock signal refers to an 8 KHz signal obtained by dividing from a 622 MHz or 155 MHz SDH optical signal input for each line, respectively. The choice is made by the operator.

When the DOTS clock is selected (504), the network synchronizers 243 and 244 receive DOTS clock signals DOTS1 and DOTS2 (505), and randomly select one of the two DOTS clocks (DOTS1 and DOTS2). (506).

Conversely, if the optical signal reference input signal is selected in the determination step 503 (504), n (4 here) reference clock signals are input from the line card 25 selected as priority in the initial step 502. Receive (507).

In operation 508, one of the plurality of input reference clock signals is selected according to the hypocrisy set by the controllers 22 and 23 in the initial step 502.

Table 1 below shows an example of the selection criteria table, and selects a synchronization clock according to a 3-bit RefSel value.

RefSel (2: 0) Selection criteria 000 Free-running 001 DOTS1 010 DOTS2 011 Ref1 100 Ref2 101 Ref3 110 Ref4 111 holdover

As described above, the selected reference clock (tip, ring) is output from the line card 25, passes through the network unit (243, 144), and is transmitted to the switch fabric (241,242). Since this is selected from a plurality of line cards in the whole system, each reference clock is in the form of a MUX of N: 1.

The network synchronizers 243 and 244 generate and output clock signals CLK1 and CLK2 required by the system in synchronization with a reference clock selected using a phase lock loop (PLL) (509 to 510). The generated system clocks CLK1 and CLK2 are TDM clocks in time division mode and ATM clocks in synchronous delivery mode, respectively. The generated system clocks CLK1 and CLK2 are transferred to the corresponding switch fabrics 241 and 242 and used for the operation of the system.

By the above procedure, each of the network synchronizer (243, 244) is to operate the system in synchronization with the network, in this case, the controller (22, 23) whether the operation of the operating network unit 243, 244, whether or not reset, etc. By monitoring the state of, control the transfer and return in accordance with the state of the network synchronizer (243, 244), which is made as follows.

While operating in synchronization with the network in the switch unit 24 as described above, if the network synchronizer control cannot be made normally, the transfer is made to the standby network unit 243 or 244 and the switch fabric 243 or 244. When the transfer is performed by the failure of the network synchronizers 243 and 244, as described above, the corresponding network synchronizers 243 and 244 perform the transfer by themselves, and the switch fabrics 241 and 242 are separate control signal lines (fail, It is switched together according to the control of the controllers 22 and 23 that recognize this through status, reset).

When switching of the switch is required, the first and second controllers 22 and 23 set a predetermined register for displaying the state of each switchboard, and change the state value of the register for each switched operation mode.

The following Table 2 shows the state values of the memory registers that indicate the operation status of each switch board in the switch board. In this operation mode, one of the first and second switch boards 24a and 24b is in a standby state and the other One side is operated or three modes in which the first and second switchboards 24a and 24b are all in a standby state.

Status value 1st switch board 2nd switch board One Act Standby 2 Standby (stanby Standby 3 Standby Act

As described above, the first and second network synchronizers 243 and 244 recognize the operation modes of the switch boards 24a and 24b to which they belong.

The first and second network synchronizers 243 and 244 check the register value as described above, and recognize the operation mode of the first and second switch boards 24a and 24b to which they belong according to the value. Therefore, the operation is performed as follows. Hereinafter, the case where the state value of the register is 1 will be described.

That is, the first network synchronizer 243 of the first switch board 24a set to the operation mode operates in the same manner as the procedure of FIG. 5 described above to synchronize with the selected reference clock. On the contrary, the second network synchronizer 244 of the second switch board 24b set to the standby mode is set from the first network synchronizer 243 of the first switch board 24a set to the operation mode and synchronized with the selected reference clock. Receive and synchronize the reference clock. In this state, when the operation mode is switched, the operation is performed as shown in FIG. 5 to synchronize the reference clock of the selected external synchronization source.

As described above, in the TDM / IP data transmission system, the present invention is configured by duplexing a network synchronizer control structure to an active side and a standby side that is replaced in the event of a failure of the operating side. In addition, it is possible to provide a stable synchronization clock to the network and to ensure the quality of service (QoS) of the system.

Claims (8)

A plurality of line cards for inputting and outputting time division multiplexing (TDM) / Internet packet (IP) data through respective communication subscriber network channels; Each of the switch fabrics for determining a data transmission path between the plurality of line cards, an external DOTS clock signal and a plurality of reference clock signals input from the line card are selected as reference clocks, and the selected reference is selected. And a network synchronizer configured to generate and provide a system clock synchronized with the clock, wherein the standby mode waits for a return of a fault according to whether or not a fault occurs in the network and a first mode operating in an operation mode performing a switching function by performing a network synchronizer. 2 switchboards; And Including the first and second controller to control the operation of each of the first and second switchboards, and to check the failure state of each of the first and second switchboards, and to transfer the control of the synchronizer to a switchboard that can operate normally. TDM / IP data delivery system that integrates TDM data and IP data. The apparatus of claim 1, wherein each of the network actuators of the first and second switching boards is used. A reference for selecting one of a DOTS clock signal received from an external DOTS (Digital Office Time Supply) and a reference clock signal of an optical signal respectively inputted through a plurality of line cards as a reference clock according to the priority specified by the first and second controllers. A clock selector; A synchronization clock generation unit generating a clock synchronized with the reference clock selected by the reference clock selection unit; A system clock generation unit generating a system clock to be used in the system based on the clock output from the synchronization clock generation unit and providing the system clock to the switch fabric; A reference clock interface unit for receiving one reference clock received from the highest level selected by the reference clock selection unit and operating normally; After monitoring the failure of the link supplying the selected reference clock through the reference clock interface unit, reporting the failure to the corresponding first and second controllers, and controlling the network synchronizer to perform the switching and phase maintenance function, TDM / IP integrated data transmission system comprising a reference clock monitoring and a control unit for monitoring the failed link to restore the network synchronizer in case of failover. The method of claim 1, Each of the first and second switchboards of the first and second switchboards is connected to a corresponding switching fabric and a data and address bus, and further, the first and second controllers and the physical signal lines to quickly cope with an urgent failure state of the first and second switchboards. Directly connected, The first and second controllers of the first and second switchboards are connected to the first and second controllers through the physical signal lines, and the first and second controllers are connected to the first and second switchboards. TDM / IP integrated data transmission system, characterized in that the connection is made via the software internal signal transmission path by the IPC (Interprocessor Communication) communication over the bus. The method of claim 3, wherein The network synchronizer reports a failure affecting the output of the reference clock to the corresponding first and second controllers through the physical signal line, and for the failure not directly affecting the network, the IPC (Interprocessor Communication) TDM / IP data integrated delivery system characterized in that the reporting to the upper first, second controller through the communication. 4. The physical signal line of claim 3, wherein the physical signal lines connecting the first and second controllers and the corresponding network synchronizers are First signal line (fail) for the fault that informs the urgent failure of the network synchronization unit, A second signal line (status) for reporting a status of the network synchronizer; And a third signal line (reset) for resetting for restarting the network synchronizer. In the method of controlling a synchronizer of a TDM (Time Division Multiplexing) / IP (Internet Packet) data delivery system comprising two switchboards each consisting of a network synchronizer unit and a switch fabric to perform data exchange between multiple line cards in a redundant operation method. In A power applying step of applying initial power to the TDM / IP data integrated delivery system; A setting step of setting the two switchboards into an operation mode or a standby mode, respectively, depending on whether the network synchronizer is disabled; An operation mode performing step of synchronizing the system by generating a system clock synchronized with the reference clock by receiving a reference clock from a preset external synchronization source of the switchboard set as the operation mode in the setting step; A standby mode performing step of synchronizing by receiving a clock from the network synchronizer of another switchboard in which the switchboard is set to the standby mode in the setting step; A monitoring step of monitoring a failure of a link providing a reference clock in a network synchronizer performing the operation mode; And According to the monitoring result of the monitoring step, changing the operation state of the switchboard of the failure of the network synchronization unit in the standby mode, the operation mode of the switchboard in the standby mode to the operation mode, and the step of repeating from the operation mode execution step A method for controlling a synchronizer in a TDM / IP data delivery system. The method of claim 6, wherein performing the operation mode A first step of giving priority to a predetermined number of channels among a plurality of input channels of a plurality of line cards, respectively, to the network synchronizer; A second step of setting whether to select a digital office time supply (DOTS) clock signal as an external synchronization source or a reference clock signal of a SDH (Synchronous Digital Hierarchy) optical signal input through the multiple line cards; A third step of selecting and inputting one of DOTS clock signals applied from DOTS in the network synchronizer when DOTS is selected as an external synchronization source; A fourth step of receiving a reference clock signal from a channel selected according to the priority given by the network synchronizer when the reference clock signal of the SDH optical signal is selected as an external synchronization source; And A network in a TDM / IP integrated data transmission system comprising generating a system clock (PLL) synchronized with a clock signal input in the third or fourth step and providing the system clock to a line card through a switch fabric. Synchronous control method. The method of claim 6, wherein the monitoring step Monitoring a failure of a link providing a reference clock in an operating network synchronizer; As a result of the monitoring, when a failure occurs, dividing the generated failure into a failure influencing the clock output and a failure influencing the network synchronization according to the extent; As a result of the classification, if the generated disability is urgently necessary, transmitting a failure fact directly to a higher controller through a physical line; And As a result of the classification, when the generated impairment affects the network synchronizer, the step of controlling the network in the TDM / IP integrated delivery system, characterized in that the step of transmitting to the upper controller through Interprocessor Communication (IPC) communication.

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