KR960007660B1 - Cdma mobile telecommunication system - Google Patents

Abstract

The method improves the reliance on controlling and managing the signal information generated from local stations and routers by dualizing the sub-system. If the first base station controller(BSC)-message switching center(MSC) signalling processor(BSP1) is out of order, it sends fault signal to BSP2. The BSP2 indicates LED for active status from alert status and sends the information to BSM and MSC. If BSP1 is restored, it performs task2 and BSP2 gets into alert status.

Description

Redundancy of BSP Subsystem of CDMA Mobile Communication System

1 is an overall system block diagram to which the present invention is applied.

2 is an overall configuration diagram of the present invention.

3 is an overall software configuration diagram of the present invention.

4 is a software configuration for redundancy of the present invention.

5 is a flowchart of a redundancy process of a BSP subsystem of the present invention.

6 is a flowchart of task 1 mounted on a BSP.

7 is a flowchart of task 2 mounted on a BSP.

* Explanation of symbols for the main parts of the drawings

MS: Mobile Station BTS: Base Tranceiver Station,

BSC: Base Tranceiver Station MSC: Message Switching Center:

MSC, CIS: CDMA Interconnect Subsystem

SBS: Selector Bank Subsystem CCP: Call Control Processor

BSM: Base Station Manager BSP: BSC-MSC Signaling Processor

PP: Peripheral Processor

IPCU: Inter Processor Communication Unit

The present invention relates to a duplication method of a BSP subsystem that reliably controls and manages signal information generated from a base station and a mobile switch in a control station among digital mobile communication systems of a code division multiplexer access (CDMA) scheme. will be.

In situations such as when the board is powered off or when the board is hermetically shut down, the current processor will not be able to continue. In this case, there is a need for redundancy to take over the status quo from other boards and maintain performance.

However, in realizing redundancy, it is important to set what will be dualized and to what extent. For example, deciding whether to focus on hardware, redundancy, software only, or all of them. For example, the target may be duplication in case of power failure, processor down, or whether to do anything related to call processing. These decisions should be determined by the system by its nature and function.

In the conventional redundancy scheme, when a processor executes a program, it is common that another processor performs a back-up of a current execution state when an error occurs. In this case, one processor is the main and the other is the dependent or the both are the main methods, and the fault tolerance is widely applied.

However, this method of redundancy is difficult to control in terms of hardware, and the items to be configured are also required more than before redundancy (eg DPRAM), and the protocol itself is complicated in terms of software and synchronization problems between tasks. Etc. Compared to the investment cost, the redundancy process is inadequate, and it is particularly ineffective and inefficient to apply to the redundancy switching only a simple transmission path.

In order to solve the above problems, the present invention can realize redundancy by operating a simple software with fault signal and LED by using a duplication method that is only responsible for switching a simple path between two devices. The purpose of the redundancy is to provide a redundancy method of the BSP subsystem among the CDMA digital mobile communication systems that provides transfer switching between the exchange and the control station in the mobile communication network when hardware related alarms and faults occur.

In order to achieve the above object, the present invention provides a BSP (BSC-MSC Signaling Processor) having a 1BSP and a first BSP for signal transmission of a control station and a mobile switching period, a message switching center (MSC) and a base station manager (BSM). In the redundancy method applied to the BSP subsystem of the CDMA mobile communication system, a failure occurs in the normally operating first BSP, and a fault signal is given to the second BSP. A first step of displaying an LED indicating an operational state in a state, and then notifying the BSM and the MSC of the fact; The program and data are downloaded from the BSM, and when the BSM downloads the initial information to each subsystem, the other subsystem is given a physical address for the first BSP to use the first BSP, and BSP1 initially Given the color of the LED, the second BSP is given the color of the standby state, the first BSP performs a task 2 and the second BSP performs a task 1 when the initial work is finished; If a fault occurs in 1BSP (or BSP1 is dismounted), the first BSP sends a signal to the second BSP that the fault has occurred to the second BSP, and the color of the LED changes and the color of the standby state in the LED of the second BSP that received the fault signal. The task 2, which is in the standby state, transfers to the transmission path of the second BSP, and when the task 2 in the standby state is resumed, the signal information transmission through the current first BSP to the BSM is transferred to the second BSP. A third step of notifying the MSC that the transmission path has been switched from the first BSP to the second BSP while requesting the transfer; The MSC receives the transfer switching notification and sends a notify response in response thereto, and the BSM receives the transfer request and informs each subsystem of the physical address of the transferred transmission channel; If the first BSP is restored, the first BSP is in the standby LED state, and task 2 is in the standby state, and the repetitive procedure is performed such that only the states of the first BSP and the second BSP (standby / active) are changed, but the same as the initial state. It characterized by comprising a fifth step.

The control station has two BSPs for information transmission, and each BSP has a transmission path independent of the mobile switching center. Initially, when only one BSP is operated but a state in which execution is impossible is performed, the transmission path is switched to another BSP.

The transmission switchover in BPS is as follows.

Alarm

-power failure

Hernia / Mounting of the Board

-processor down

-signalling path failure

Fault

-start self test fault

-watchdog time out

-processor restart

-processor switch over

-ethernet link fault

The redundancy function for channel switching is performed on the kernel and consists of Task 1 and Task 2, which are S / Ws loaded on the BSP. Task 1 is responsible for initial replication and task 2 is responsible for the actual redundancy process.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram showing the entire system to which the present invention belongs, and is composed of systems such as MS, BTS, BSC, and MSC. The BSC is further divided into five subsystems: CIS, SBS, CCP, BSM and BSP.

All voice and signal information from the BTS or MSC is transmitted to other subsystems through the CIS within the BSC system. The CIS and all subsystems are connected to each other through the T1 / E1 interface, and the packet data transmitted and received has the HDLC format structure.

The functions of each subsystem of the control station are as follows.

(1) CIS

Provides a transmission path of packet data for reception of packet data for reception of voice and signal packet data from a BTS or MSC. All subsystems in the BSC are connected to each other via this shared bus and the supported speed is 100 Mbps.

(2) SBS

It has a function of converting voice information received from the BTS into a 64 kbps PCM signal, that is, a vocoder function, and a function of converting voice information related PCM signals received from the MSC into voice information.

(3) CCP

It performs the radio signal protocol function of the BSC system. That is, it has a function for connection between BTS-BSC and BSC-MSC. For example, call setup and release functions, selector management functions, and soft / soft handoff processing functions.

(4) BSM

It monitors and manages the status of all subsystems in the BSC and reconfigures the subsystems when a fault occurs in a specific subsystem.

(5) BSP

It transmits the signal information from the BTS or MSC to the MSC or BTS transparently. In addition, the signal information matching function is performed to transmit the signal information frame from the BTS or the MSC to the MSC or the BTS. The maximum supported transmission rate is 1 Mpps. It also performs redundancy when a fault occurs in the BSP subsystem.

2 shows the overall configuration of the present invention, wherein the BSP for signal transmission in the mobile switching period with the control station is composed of BSP1 and BSP2. In general, BSP1 transmits signal information with the MSC's PP through IPCU, which is a basic IPC network. If a failure occurs in ESP1, the transmission path is switched to BSP2 instead of BSP1.

The BSP1 and BSP2 for redundancy between the control station and the mobile switching center have independent transmission paths, and the BSP1 and BSP2 inform each other of fault signals to perform redundancy, but do not share the state information of each other.

The BSP has a status LED, which is green when it is in operation, red when it is broken, and yellow when it is in standby.

3 shows the overall S / W function of the BSP. It consists of application S / W such as IPC, CIS, MSC and BSM interface that connects between BSC-MSC, and BS_AP for connection with higher protocol of CCP. In addition, the I / O driver of the BSP and the redundant processing software of the BSP also communicate with other subsystems through the kernel.

Figure 4 is a software architecture diagram for the redundancy processing of the BSP subsystem. It is composed of Layer 1, Layer 2, Layer 3, and the management layer based on Q.940 / Q941 / Q942 recommended by CCITT. .

The bearer service of layers 1-3 responsible for transmitting signal information is Inter Processor Communication (IPC), and the redundancy process is designed to be performed by a task of a management layer.

Task 1 is the entity that handles the initial state mentioned above, and Task 2 is the entity that actually performs the redundancy. Task 1 has the initial data received from the BSM and is notified by the BSM whether Task 2 will be active.

The function of each task is as follows.

(1) Task 1

Task 1 receives the initial data from the BSM and keeps waiting. The initial data includes:

Initial state information of subsystem in BSC

Status information of BSP

Status Information = 0: Standby State

1: Active state

(2) task 2

Task 2 performs the redundancy procedure according to the previous procedure when receiving a fault signal from the counterpart BSP.

5 is a block diagram showing a processing procedure when a fault occurs during the duplication processing procedure of the BSP subsystem to which the present invention is applied. If a fault occurs in BSP1 that normally operates and a fault signal is given to BSP2, the BSP2 displays a green LED indicating an operating state in the standby state and then notifies the BSM and the MSC.

(1) Initial state

Download programs and data from BSM.

When the BSM downloads initial information to each subsystem, the other subsystems are given a physical address for BSP1 for use by BSP1.

BSP1 is initially yellow when BLED2 is green because BSP2 is in standby.

BSP1 performs task 2 when the initial work is done, and BSP2 performs task 1.

(2) If a fault occurs in BSP1 (or BSP1 is hernia)

BSP1 signals BSP2 that a fault has occurred to BSP2 and the LED turns red. Upon receiving a fault signal, the BSP2 changes from a yellow LED to a green LED, and task 2, which is in standby, switches to the transmission path of the BSP2.

When Task 2, which was in the waiting state, is resumed, it requests the BSM to transfer the current signal information transmission through BSP1 to BSP2 and notifies the MSC that the transmission path from BSP1 to BSP2 has been switched. do.

The MSC receives the transfer switch notification and sends a notify response in response.

After receiving the transfer request, the BSM informs each subsystem of the physical address of the transfer.

(3) After the process of (2), if BSP1 is restored, BSP1 is in yellow LED state and task 2 is in standby state. Then, only the state (standby / active) of BSP1 and BSP2 is changed, which is the same as the initial state of (2), and redundancy is realized by the repetitive procedure of (2) and (3).

FIG. 6 is a block diagram showing a task 1 function for a redundancy process of a BSP subsystem to which the present invention is applied, in which FIG. 6-1 is an initial state of task 1, and 6-2 is a program of a BSP from a BSM. Initial data input, 6-3 indicates initial data storage and status flag check of BSP, and 6-4 indicates fault flag.

7 is a block diagram showing a task 2 function that is responsible for a redundancy processing procedure of a BSP subsystem to which the present invention is applied. In FIG. 7-1, an initial state of task 2 is generated, and 7-2 is a fault occurring in BSP1. It is shown. 7-3 indicates that a fault generation signal is input from BSP1. 7-4 indicates downloading initial data from BSM to BSP2. 7-5 indicates the transfer transfer of the BSP, and 7-6 indicates a response to the notification.

Therefore, the present invention as described above can realize the redundancy by operating a simple software with fault signal and LED by using the redundancy method that is only responsible for switching the transmission path between the two devices, and the redundancy of the BSP is hardware In case of related alarms and faults, transfer switching is provided between the exchange and the control station in the mobile communication network.

Claims (1)

CDS including a BSP (BSC-MSC Sig-nalling Processor) having a first BSP and a first BSP for signal transmission during a mobile switching period, a MSC (Message Switching Center) and a BSM (Base Station Manager) In the redundancy method applied to the BSP subsystem of the CDMA mobile communication system, when an abnormality occurs in the normally operating first BSP and a fault signal is given to the second BSP, the 2BSP indicates an operation state in a standby state. After the LED is displayed, a first step of notifying the BSM and the MSC of the fact; The program and data are downloaded from the BSM, and when the BSM downloads the initial information to each subsystem, the other subsystem is given a physical address for the first BSP so that the first BSP is used, and BSP1 initially Given the color of the LED, the second BSP is given the color of the standby state, the first BSP performs a task 2 and the second BSP performs a task 1 when the initial work is finished; If a fault occurs in the first BSP (or the BSP1 is dismounted), the first BSP sends a signal to the second BSP that the fault has occurred to the second BSP, and the color of the LED changes and the standby state of the LED of the second BSP that receives the fault signal. The task 2 in the standby state changes to the transmission path of the second BSP, and when the task 2 in the standby state resumes, the signal information is transmitted to the BSM via the current first BSP. A third step of notifying the MSC that the transmission path has been transferred from the first BSP to the second BSP while requesting the transfer to the second BSP; The MSC receives the transfer switching notification and sends a notify response in response thereto, and the BSM receives the transfer request and informs each subsystem of the physical address of the transferred transmission channel; If the first BSP is restored, the first BSP is in the standby LED state and task 2 is in the standby state, and the procedure of repeating the same state as the initial state is performed only when the states of the first and second BSPs are changed (standby / active). A method for redundancy of a BSP subsystem of a C. D. M. (CDMA) mobile communication system, comprising a fifth step.