Centralized monitoring and management system for telecommunication transfer box based on public telephone network
With the continuous development of communication technology and the continuous expansion of the scale of telecommunication networks, a large number of remote modules and new access technologies have been adopted in modern telecommunication networks. The total capacity and the number of sets of wiring and distribution equipment have increased significantly. In order to maximize the profits of their companies, network operation companies will tend to maintain the distribution and distribution equipment unattended, remotely monitored automatically, and centralized management.
Moreover, the dependence of telephone users on telecommunication networks is also increasing, and the requirements on the service quality of telecommunication network operating companies are becoming higher and higher. As an important part of the telephone access network, the wiring and distribution equipment of local telephone cables directly connect users. The maintenance and management of these equipments are directly related to the service quality and service level of users; at the same time, due to the low technical content of these equipments The input of Heqiang labor force makes the maintenance personnel's overall quality lower and the management more chaotic. As the main line-distribution equipment, the local telephone exchange box is frequently opened and moved by various construction personnel, which can easily cause communication interruption. And because the maintenance personnel can open the door of the box at will and then change the line at will without updating the data, which leads to the inaccurate data of the handover box, the wiring is not standardized, and it is easy to be damaged by illegal personnel due to the incomplete locking of the door The user's phone is stolen and the telephone line is picked up privately, which makes it difficult to improve the accuracy of the local telephone line and becomes an important part of frequent failures.
Based on this situation, how can telecom network operating companies adapt to new needs, use modern technology and methods to manage the wiring and distribution equipment of local telephone cables, and can quickly find and eliminate faults when there is no one on-site Very necessary. The application of the centralized monitoring and management system of the PSTN-based local telephone transfer box can solve the above contradictions well. It can control and manage the opening and branching data of the transfer box, and can also alert and signal the illegal intrusion of the transfer box. .
1 System working principle 1.1 System structure The whole system adopts the structure of client / server + tree control. Figure 1 shows the networking diagram of the centralized monitoring and management system. The structure and function of each part are summarized as follows: the connection between the client and the server is strictly through the central database on the server, abandoning the previous DDE, OLE and other data transmission modes, which is convenient to improve reliability and simplify programming tasks. The interaction between the client and the server is mainly manifested in two aspects: one is the read and write operation of static data; the other is the read and write operation of dynamic data. For dynamic data, a dynamic table that is updated at any time is built on the server database, and the client reads the database every certain time and judges its status change. The remote commands that the client needs to execute (such as single-box monitoring, remote unlocking, etc.) use the command operation code agreed in advance to change the corresponding field content of the corresponding table of the database on the server, and the server queries every certain time (or uses event triggering) Search) the content of the corresponding field; then interact with the foreground to perform the corresponding action. This structural design limits the connection between the client and the server to the database, which greatly improves the reliability of the system operation, and is sufficient for such a system that is not very real-time.
The operating environment of the server-side software is WINDOWS NT SERVER 4.0, and the server-side programs are run using NT-specific background services (SERVICES). The program does not have a visual interface, it starts automatically when NT is started, and automatically terminates when NT is terminated. The adjustment of the software operating parameters can be performed through the dedicated interface of the control panel, which greatly improves the reliability, eliminates human error, and can achieve normal operation 24/7.
The connection method between the client and the server can be either Ethernet LAN or remote telephone dialing to enter the LAN where the server is located. If conditions permit, you can also use the browser to interact with the server through INTERNET. The method is actually very simple. The server has its own DNS and IP addresses. The CGI or ASP technology is used to read and write the SQL SERVER 7.0 database. The client just calls the server-side HTML. In this way, you can make full use of advanced technologies such as online paging and automatic E-MAIL services to achieve instant alarms. The server program is always running in the background and constantly updating the database, and does not interfere with the WEB system, which is also the biggest advantage of this method.
The client in Figure 1 is composed of a multimedia computer and access equipment. It can perform comprehensive monitoring, control, and maintenance of each transfer box in a certain area. It can also edit, store, record, query, and print related materials. The application of each client is the same, the only difference is its service scope and permission level. For clients in different places, or for different operators, the system can give different levels of authority. The highest-level client performs the duties of an administrator, is responsible for the normal operation of the entire system, and is responsible for authorizing different clients, and it can also perform comprehensive monitoring and maintenance of the entire system; it can store, record, query and print all data . It can be seen that this structure provides great flexibility for the construction of the entire system. Such a client can monitor up to 256 remote monitoring units.
The remote monitoring unit is a microcomputer-based system based on a single-chip CPU. The machine is equipped with MODEM and is connected to the central server system via PSTN. Each remote monitoring unit is installed in a branch office, branch office, module office or access point, which can monitor and control all the transfer boxes to which the exchange office belongs in real time, and report all kinds of information in time. If the transfer box directly connected to it is opened illegally, the monitoring unit can immediately call the BP of the boxer responsible for the transfer box to make an alarm and report it to the central server in time, and the central server will transmit the alarm signal to the corresponding client . The central server can also actively control the behavior of the remote monitoring unit, such as collecting the historical records of the handover box operation, collecting the boxer password, remote unlocking, single box monitoring, etc. The collected data will be stored in the machine's central database. On the one hand, it is convenient for centralized management, and on the other hand, it is conducive to protecting the security of data. The client's operation of the transfer box is completed by the central server controlling the corresponding remote monitoring unit. A large-capacity remote monitoring unit can monitor up to 256 transfer boxes.
The lowest level of the system is the monitored object, that is, each transfer box. The remote monitoring unit is directly connected to each junction box through a cable. An electronic lock is installed on the junction box. If an abnormality occurs or the connection between the junction box and the remote monitoring unit is cut, an alarm message will be generated immediately.
The connection between the server and the remote monitoring unit uses multiple serial port cards to connect multiple MODEMs. The system service program uses TELEPHONE API to establish and manage MODEM connections, uses the standard WINDOW API file processing function to handle data exchange, and uses parallel port I / O and multi-thread technology to manage the communication link; at least three threads should be included in the server application: As the main thread to manage the normal operation of the program, the other two threads, one for the read channel and one for the write channel. It uses event triggering (interrupt mode) to read and write data; when no event is triggered, the thread is put to sleep to save CPU resources to the greatest extent, and then wake up the thread when an event is triggered. In order to increase versatility, the TAPI function must be used when establishing and managing MODEM connections. Its low-level communication program should complete the functions of data packing and unpacking, data sending and receiving, data validity checking, data transmission integrity guarantee, communication link on and off, and communication link failure recovery.
In short, the system is a data-centric application, and the operations of the client and server are actually around the database. The central database builds a bridge between each client and server, and its structure is shown in Figure 2.
1.2 The work flow of the system is illegally turned on when the transfer box is the simplest application. The information flow is shown in Figure 3. When the junction box is opened illegally or its connection with the remote monitoring unit is cut off, an alarm message is issued. After the remote monitoring unit obtains the alarm information, it picks up the phone and dials the phone of the central server, and after receiving the response signal, transmits the packaged alarm information to the central server. The alarm information contains the ID and alarm code of the transfer box where the alarm occurred and the date and time when the alarm occurred. After receiving the response signal, hang up to end the information transmission process. The central server stores the received alarm signals in its central database. When the corresponding client checks the alarm queue of the database on the server at every time (10 ~ 60S), it will get the alarm information, and promptly remind the operator by voice or text. It can be seen that the time delay will not exceed 5MIN from the time the alarm is issued until the client finally knows the alarm.
In addition, the central server can also call each front-end remote monitoring unit one by one to test the hardware system, correct the clock, or make the selected monitoring unit send the operation history information records of each transfer box it stores for corresponding analysis and processing and enter it into the database. . The client can also perform remote unlocking or single-box monitoring tasks for a handover box. As mentioned earlier, this behavior is performed by the server.
2 System functions The system can realize the following functions:
· One or two password electronic locks are equipped on the monitored transfer box to control the front and rear doors respectively. Through the correct operation of the boxer or system administrator, the electronic lock can be controlled to open and record the corresponding information.
· The box operator connects the phone to the transfer box I maintain, dials my unboxing password to open the front and back doors of the transfer box; dials the internal call prefix to talk to the system administrator; dials the local call prefix Talk to ordinary local users; dial the password prefix and change your old password and new password to modify your own password.
· The administrator can manage the phone through the client or system to perform remote unlocking.
· When the handover box is damaged, illegally invaded, or the door is opened for a long time, the remote monitoring unit can send a BP signal to notify the maintenance personnel to process and record it in a timely manner; Sound and light alarm on the client.
· Can record, query, print, and summarize the operation history of each transfer box, including the start and end time of each transfer box and the name of the operator; the occurrence and repair time of the illegal intrusion event; the time of the remote unlocking event and the request of the unlocker Name.
· The client can display the use status of all handover boxes in a timely manner, including phone off / on-hook status, door opening / closing status, and handover box alarm status.
· Able to display and print all the data of any one of the transfer boxes on the client, including the transfer box number, installation and use date, installation location, the cumulative number of failures, the name and password of each maintenance personnel and the transfer box number under their jurisdiction .
3. Communication agreement and database 3.1 Communication agreement The central server and each remote monitoring unit are respectively installed with MODEM, and the middle is connected by dialing through PSTN. When the central server initiates communication, it first dials the telephone number of the remote monitoring unit, and the remote monitoring unit automatically answers after receiving the ringing signal and enters the data communication program; when the remote monitoring unit initiates communication, the central server also automatically answers and Receive data. When it is found that the communication is out of synchronization (that is, the length of the frame header and the frame tail is mismatched in the received frame) or the checksum error, the receiver sends back NAK (06H). When the sender receives the NAK, it first sends 5 consecutive frame headers and frame tails, and then retransmits the upper group command. If it fails 5 times or the communication times out, it exits the online state and requests to reconnect. The receiver in the communication process can continue to send / receive other commands only after receiving and sending the confirmation signal ACK (15H); the sender in the communication process can only continue to send after receiving and receiving the confirmation signal / Receive other commands.
Each control and transmission command adopts ASCII code transmission, with frame header 05H and frame end F5H as the synchronization code of one frame of data. The data format is shown in Table 1.
3.2 Database The database is mainly composed of the following eight tables to describe the system information and its related information, as shown in Table 2. The eight tables listed in the table, the first five are static data tables, and the last three are dynamic data tables, which need to be updated at any time. Among them, the operation user data table is used to set the operation area and authority level of each client. The BP machine number stored in the boxer data table is used when the remote monitoring unit automatically sends BP machine information. The transfer box status data table is used to continuously update the changes of the client software transfer box status. If an alarm message is generated by a transfer box, the alarm data is also stored in this table. The remote command processing queue is that each client sends commands to the server database to execute commands such as remote unlocking and single-box monitoring, and the server software is queued for execution in order of the queue.
In short, the remote distributed telecommunications transfer box monitoring and management system has large monitoring capacity, convenient networking, stable performance, relatively low implementation cost, and strong compatibility with other monitoring systems. It can monitor the transfer box and the distribution frame at the same time, and can transfer Box sub-line data to achieve computer management. Practice has proved that it is very effective for the unattended distributed remote centralized monitoring of the transfer box.
Guangzhou Ehang Electronic Co., Ltd. , https://www.ehangmobile.com