[b]I. Introduction[/b] Considering the frigid winters and scorching summers in most Chinese cities, key components in the street light monitoring system are all military-grade products. These products undergo uniform low-temperature and high-temperature aging tests before leaving the factory. We can choose GPRS as the system's communication method. Currently, most cities in my country will gradually launch GPRS services, which is the mainstream transmission resource for future street light monitoring systems and an inevitable trend in communication methods. Previously, street light inspections were a labor-intensive task for municipal departments. Now, the application of GPRS networks in this area has automated the inspection work. Xiamen Lans Communication Co., Ltd., in collaboration with system integrators, has developed a night scene lighting monitoring and management system specifically for municipal departments. This system utilizes an advanced GPRS network, integrating multiple advanced technologies such as computer, communication, electromechanical, and automatic control. It successfully achieves real-time monitoring and management of night scene lighting systems and streetlights, ensuring efficient, stable, and 24/7 operation. Compared with night scene lighting systems in other cities, its advantages are obvious. The China Mobile GPRS network used in this solution is a mainstream technology and an inevitable path towards third-generation mobile communication. It boasts advantages such as always-on connectivity, fast login, high-speed transmission, pay-as-you-go pricing, and seamless switching. It overcomes the shortcomings of wired and wireless trunking communication methods, including long construction cycles, large investment scales, immature technology, and limited terminal support. This enhances the system's technological content, ensures stability, significantly reduces construction investment and operating costs, and lays a solid foundation for future system upgrades, making it the most ideal nighttime lighting monitoring and management system currently available. In terms of both functionality and reliability, no wireless network can compare to mobile communication networks. Overall, it offers the following advantages: 1. Wide coverage: Currently, mobile communication networks cover over 95% of the country, with near 100% coverage in non-remote areas. GPRS users can freely distribute and move their network points without worrying about line maintenance or communication interruptions caused by wired relocation. Building new monitoring points requires no wiring or burial work. Investment is lower than fiber optic or dedicated line systems, and equipment installation is convenient. Long communication distance: Central stations can be set up in any location. 1. **Superior Coverage:** Compared to many wireless data networks (trunking, two-way paging, CDPD, CDMA), its network coverage is the best. 2. **Fast Access Speed:** GPRS offers fast access speeds and seamless connectivity with existing data networks. As a packet-switched data network supporting TCP/IP and X.25 protocols, it bypasses PSTN and other networks, directly communicating with packet-switched data networks (IP or X.25 networks) at speeds of only a few seconds, faster than circuit-switched data services. Using the TCP/IP protocol, network access is more direct and convenient than previous wireless data networks (trunking, two-way paging, GSM SMS). 3. **High Network Reliability:** The network boasts significant redundancy in equipment and channels; equipment reuse; and rapid repairs by mobile companies in case of base station damage. 4. **High Stability:** It is highly resistant to natural interference and uses dedicated frequency bands, preventing human interference. GPRS best supports frequent, low-volume bursts of data traffic. Communication quality is stable and reliable, with no dropped connections. 5. **Affordable and Reasonably Charged Rates:** GPRS tariffs are inexpensive. GPRS monthly plans are cheaper than wired telephone network plans. Streetlight monitoring data collection services do not involve large data transmissions, so there's no need to use expensive dedicated lines (DDN, Frame Relay). GPRS also allows for billing based on the amount of data transmitted and the quality of service provided. In a GPRS network, users only need to establish a connection once and can maintain that connection for a long time. The channel is only occupied and charged when data is being transmitted; no charge is incurred when the channel is not occupied during the connection period. This way, service providers don't need to frequently establish connections or pay for intermittent transmission fees. GPRS is a new technology in mobile communication networks that enables wireless Internet access. This technology transmits data in packets (TCP/IP) and provides a transparent channel. Network capacity is allocated only when needed; once the packets have finished transmitting, the channel capacity is immediately released, providing instant connection and efficient transmission, enabling real-time online functionality. Therefore, it is a cost-effective packet data technology. In terms of networking, both the master and slave devices can use either dynamic IP or fixed IP. When forming a small-scale monitoring network, both the master and slave devices use dynamic IP and dynamic domain name resolution to use the public network, which can save costs (no need to lease dedicated lines such as DDN). When forming a large network, the host can use a fixed IP and a dedicated network to improve system efficiency. However, when conditions are not available, dynamic IP and the public network can still be used, and the efficiency is only 0.2% lower than that of fixed IP. [b]II. Overview of Technical Solution[/b] 2.1 Technical Features Our design has the following main features: 1) The network version software design allows for convenient operation on any networked computer, making remote networking very easy. The monitoring center can be accessed remotely via telephone line to browse its data. 2) To ensure the secure operation of the system on the public network, the monitoring center uses multi-level operation passwords, and automatic dynamic password protection is used between the monitoring center and the sub-control points. During the day, when the lights are turned on, the monitoring center sends dual commands to the sub-control points to execute control commands, ensuring absolute security of remote control operations on the sub-control points. 3) A highly intelligent data acquisition device, entirely developed and manufactured in-house, possesses independent intellectual property rights and is widely used in telecommunications systems. We can freely modify the design according to user needs without being constrained by non-self-designed products. 4) Sub-control points can independently control streetlight equipment and record historical data. Even if the monitoring center malfunctions, it will not affect normal light switching. 5) Intelligent power transmission equipment can accurately calculate true RMS values ​​of voltage and current, and measure parameters such as power factor in complex waveforms. 6) In addition to operating using an ADSL dedicated line (main route), it also supports backup routing (it is recommended to provide a dial-up line or telephone line). This way, even if the main route fails, the backup route can automatically take over, ensuring uninterrupted operation of the monitoring system. 7) In addition to the main transmission resources, we can also provide backup transmission resources. Once the main transmission resources fail, the backup transmission resources can immediately take over, ensuring uninterrupted operation of the monitoring system. 8) Both the monitoring center and sub-control points adopt uninterruptible power supply design. 9) To prevent the DTU from going offline at the sub-control points, a WATCH DOG function has been added. When the DTU goes offline, it can automatically reset and reconnect to the network. WATCH DOG effectively prevents accidental reconnection by others and DTU offline issues. 10) Supports remote voice query, remote voice alarm, and SMS alarm. SMS messages can be displayed on the maintenance personnel's mobile phone in English or Chinese. 2.2 Design Basis and References The design is primarily based on: Beijing Municipal Street Light Management Office's "Several Explanations Regarding Street Light Monitoring Systems"; Shenzhen Municipal Street Light Management Office's "Tender Requirements for Shenzhen Street Light Centralized Monitoring System"; Harbin Municipal Street Light Management Office's "Technical Requirements for Street Light Monitoring Systems"; "Telecommunications Transmission Manual"; and the Ministry of Information Industry's Telecommunications Administration's "Centralized Monitoring System for Power Equipment and Environment in Post Office Buildings." Additionally, the system design also references the following technical specifications and standards: GB8566 Computer Software Development Specification; GB/T12504 Computer Software Quality Assurance Plan Specification; GBJ93-86 Industrial Electrical Automation Instrumentation Engineering Construction and Acceptance Specification; GBJ232-82 Electrical Installation Engineering Construction and Acceptance Specification; GB11920-89 General Technical Conditions for Centralized Control Devices for Power Plant Electrical Components; GB4720-84 Low-Voltage Electrical Appliances and Control Equipment JECC144 Low-Voltage Switchgear and Control Equipment Enclosure Protection Rating ANS1488; Digital Interface for Programmable Instruments. 2.3 The system design principles are based on reliability and practicality, while also considering advanced technology. 1) Advanced Technology: The entire system will remain advanced for at least five years, and the equipment and technology used will be adaptable to future development. 2) Scalability: It can adapt to increasing business needs; when adding new sub-control points, only a few components need to be added. 3) Openness: The entire network is an open system, capable of incorporating products from different vendors, rather than being a system provided by a single supplier. 4) Flexibility: The system offers flexible networking methods, flexible configuration of system functions, and flexible utilization of existing resources, integrating the use of various types of resources into the networking scheme. It can meet the business needs of different sub-control points, with comprehensive software functions and convenient configuration. 5) Reliability: The networking equipment and network scheme are reliable, and backup routes can be adopted according to the needs of the street light management office. 6) Operability and Maintainability: The system is simple and easy to learn, and operators can quickly master its operation. The monitor itself and field equipment have clear interfaces, allowing for rapid identification of fault causes when problems occur, facilitating use and maintenance. 7) Practicality: From the user's perspective, the system makes it possible for street light control boxes to be operated by fewer or no people. Make full use of existing resources and minimize the cost of purchasing equipment to make the system have a high performance-price ratio. 8) Real-time performance: The system has a fast response performance. 2.4 Overview and design considerations of street light monitoring system (1) Monitoring objects At present, the street light power distribution equipment in various cities in my country is generally no more than the following types: 1) Box-type transformer A. Low voltage system: B. a. Current of 12-24 outgoing circuit low voltage outgoing line measuring points, current value 10-100A b. Low voltage line voltage value, 0-450V (a, b, c three phases, designed according to three voltage values) c. "Open" and "close" control quantities of 1-4 100A AC contactors (calculated according to four AC contactors) 2) Bench-type transformer (no high voltage system) A. Low voltage system: Same as box-type transformer. B. a. Current at monitoring points of 12-24 outgoing low-voltage circuits, current value 10-100A (calculated based on 24 outgoing lines) b. Low-voltage bus voltage value, 0-450V (a, b, c three phases, designed based on three voltage values) c. "Open" and "Close" control quantities of 1-4 100A AC contactors (calculated based on four AC contactors) 3) Other independent low-voltage power supply systems (transformerless distribution boxes) Current of 3-12 low-voltage power supply circuits, current value 10-100A (calculated based on 12 current values) 4) High-voltage power supply system A. "Open" and "Close" control quantities of the operating circuit of the distribution cabinet with 1-4 current input and output lines in the high-voltage control center (calculated based on 4 control quantities). B. High-voltage current values ​​of 3-12 input and output lines (calculated based on 12 current values). C. Voltage values ​​of 3 high-voltage busbars (calculated based on 3 voltage values) D. Power factor value of the high-voltage system. E. Power value of main incoming current (calculated as one power quantity). F. Live indication of 2-4 high voltage incoming and outgoing lines (calculated as 12 live display signals). 5) Safe operation parameters of power distribution room: leakage voltage of power distribution box, ambient temperature of power distribution box, door opening alarm of power distribution box, other optional parameters: smoke alarm (for power distribution boxes with transformers) water immersion alarm (for floor-mounted power distribution boxes) infrared alarm (for power distribution room) ID card or password keypad unlocking system (for power distribution room) transformer oil temperature (when dry transformers are used or oil temperature measurement is inconvenient, transformer surface temperature can also be measured) cable fault (2) Monitoring system scale The monitoring system is a two-level structure: 1 monitoring center: located in the duty center of the street light management department. N sub-control points: each control box is equipped with one sub-control point. The system supports up to 2048 sub-control points operating at the same time, which can meet the needs of any city. (3) Communication resources provided The system supports GPRS as the main transmission resource. It has many advantages such as low initial investment, easy installation, low usage fee, and strong anti-interference ability. It is recommended that the main transmission resource of the monitoring center can be accessed by ADSL dedicated line to GPRS, and the backup transmission resource can be accessed by GPRS MODEM. (4) The overall design principle of our company is: overall planning and phased implementation. The system design is considered as the whole project, and the system implementation can be carried out in stages. Through wireless communication networks such as GPRS, computer control system and geographic information system, remote control, telemetry, remote signaling and management functions are realized. (5) In addition to completing the necessary functions specified in the overall plan, our company can realize color dynamic image monitoring of each night scene of the city lights. The on-site image of the scene can be directly seen in the monitoring center. The display effect is comparable to that of photos. This image monitoring method has a very superior performance-price ratio. III. Composition of the monitoring system 3.1 Structure of the monitoring system (1) Connection between terminal equipment and GPRS equipment The LZ713C is characterized by embedding the TCP/IP protocol, which can be connected to the street light controller equipment in a two-way transparent manner without the need for customer development interface. Each street light is equipped with a street light controller, which can be connected to the LZ713C via the RS232 interface. (2) GPRS wireless network: The LZ713 series GPRS DTU products, which use the lines and interfaces provided by China Mobile, have been successfully applied in various industries across the country and are fully compliant with China Mobile standards. (3) Connection between GPRS wireless network and central software: The monitoring center is connected to the China Mobile GPRS network via a 2M dedicated line. The routers of both parties are connected via private IP addresses for wide area communication. A GRE tunnel is used between the GGSN and the China Mobile interconnection router. China Mobile allocates a dedicated APN for the entire monitoring system. Ordinary users are not allowed to apply for this APN. The SIM card used for the GPRS private network is only activated with this dedicated APN and is restricted from using other APNs. The monitoring center can build its own RADIUS server and DHCP server. The GGSN provides the user's calling number to the RADIUS server and uses a combination of calling number and user account authentication. After the user is authenticated, the DHCP server assigns a static IP address for the enterprise. The LZ713C GPRS DTU and the monitoring platform use end-to-end encryption to avoid possible information leakage during the entire transmission process. Both parties are isolated by firewalls, and IP address and port filtering are performed on the firewalls. (4) Connection between LZ713C GPRS DTU and central software The LZ713C GPRS DTU has completed the development of mature software interfaces. This includes the development of dynamic link libraries and a complete DEMO program. Customers can communicate with the central software by performing simple secondary development using the above software. 3.2 Introduction to GPRS DTU The GPRS DTU (Data Transmission Unit) is specially designed for the increasingly mature GPRS technology. This DTU supports the standard AT command interface, which greatly facilitates program design. It has a standard RS232 interface, which can be easily connected to our street light monitor. GPRS DTUs are currently manufactured in the United States, France, Canada and Taiwan. The technology in this area is also very mature in China. The product (LZ713C GPRS DTU) used in this project by Xiamen Lans Communication Co., Ltd. has stable performance and a better cost performance than similar products. Key Technical Specifications of the GPRS DTU: The GPRS data transmission terminal enables communication between the monitoring center's main station and the traffic controller. This system uses the LZ713C GPRS DTU from Xiamen Lans Communication Co., Ltd. The DTU's functions and features are as follows: A. Functions: 1. Standard AT command interface for convenient program design; 2. Embedded TCP/IP Internet protocol stack for easy interconnection; 3. RS232 interface for simpler communication; 4. Program can be upgraded via serial port. B. Performance: 1. Utilizes a low-power, high-performance CPU as the processor, with a 32-bit internal data bus, 4MB SRAM, and 2MB FLASH, enabling high-speed processing of protocols and large amounts of data; 2. Supports fully transparent and frame-formatted data transmission; 3. Supports TCP, IP, PPP, ICMP, UDP, TELNET, and HTTP protocol stacks; 4. A SIM card slot compliant with the ISO7816-3 IC card standard, supporting GSM11.11 and GSM11.10 compliant SIM cards; 5. Simplified interface design, using a universal RS232 interface and a simple AT command interaction interface; 6. Provides a more convenient power interface, allowing for both external power supply and direct power from the serial port; 7. Total power consumption is less than 3W; 8. Improved functions for GPRS networks, such as fake dialing, automatic restart after disconnection, and remote wake-up; 9. Supports remote control and dynamic domain name resolution; 10. Furthermore, it meets the requirements of embedded systems, providing a built-in module (which can be directly connected to the embedded system via pins). 11. It also features dual hardware and software watchdogs, automatically powering off and resetting if the DTU malfunctions. After powering on, the LZ713C GPRS DTU actively accesses the monitoring center server based on its pre-set internal IP address or domain name, establishing a TCP/IP link with the monitoring center through the enterprise firewall. The monitoring center master station maintains the IP address and ID number of each connected terminal. When the master station needs to request data from a monitoring terminal, it finds the corresponding terminal based on the IP address and ID number, sends the command to that terminal, and the terminal responds by sending the data to the monitoring center master station through the LZ713C GPRS DTU, thus completing a response-based communication process. 3.3 Components and Functions of the Monitoring Center (SC) The monitoring center (SC) is the center for the operation, maintenance, processing, statistics, analysis, and supervision of the entire street light monitoring system, and is responsible for interconnecting with other management networks. The fully networked design allows any networked computer to browse (provided it has the operating permissions granted by the monitoring center) and facilitates convenient remote networking. In the pilot project, the monitoring center consists of a database server, a front-end monitoring workstation, a back-end monitoring workstation, a printer, a hub, and an access control system. A large-screen simulation display is installed in the monitoring center, allowing real-time monitoring of the operational status of all sub-control points on the simulation screen map. The simulation screen uses a large-screen rear-projection projector to display an electronic map of the city's street light distribution and is controlled by the monitoring center's computer. The database server is a dedicated server, the front-end monitoring workstation uses an industrial control computer, and the back-end monitoring workstation uses a brand-name microcomputer to ensure high system reliability. The monitoring center employs an uninterrupted power supply design. 3.4 Photosensitive Control System In actual operation, severe weather and cloud cover often necessitate turning on lights in advance. Therefore, the monitoring system should be able to collect outdoor natural light intensity signals and alert operators whether to turn on lights in advance when the illuminance is too low. This photosensitive control system consists of a photosensitive detector (including power supply) and a data acquisition unit, connected to the monitoring host via an RS232 interface. The monitoring host periodically reads the collected illuminance values. If the illuminance exceeds the limit, a prompt message will pop up on the workstation interface: "Illuminance too low, please turn on the streetlights if necessary." If no operator confirmation is received within 5 minutes, this message can also be sent to maintenance personnel via SMS. Maintenance personnel can then send back confirmation via SMS. To prevent false alarms, three or four photosensitive probes can be used, issuing prompt messages according to a 2:1 or 3:1 decision ratio. 3.5 Uninterruptible Power Supply System: Two internationally renowned brand uninterruptible power supplies are selected. One is a 1KW 8-hour long-delay UPS to ensure the normal operation of the front-end monitoring workstation (monitoring host) after a power outage. The other is a 1KW short-delay UPS to ensure the server can shut down normally during a power outage. 3.6 Brief Design Scheme of the Monitoring Center Computer Room: The central computer room can typically be divided into two parts: an equipment room and an operation room. The equipment room houses power distribution equipment, UPS, batteries, a large-screen projector, network equipment, communication equipment, a voice service platform, servers, front-end monitoring workstations, and other equipment. The control room is equipped with an operating console, a background monitoring workstation, a management workstation, a printer, and other equipment. The control room should be convenient for operators to work, easy for leaders to provide on-site guidance, and also provide necessary living and facility space for on-duty personnel. The equipment room must use anti-static flooring, while the control room can use anti-static flooring or carpet. In principle, aluminum alloy cable trays should be used for wiring, and strong and weak current cables should be separated. The cabinet, control console, and metal cable trays should all have good grounding measures. 3.7 Grounding System of Street Light Monitoring System The main purpose of the grounding system is to: (1) prevent hazards caused by leakage current, high voltage induction, etc., and protect equipment and personal safety (2) ensure the normal operation of microelectronic systems without interference (3) prevent lightning strikes Based on the above purposes, people have designed a variety of grounding systems. (1) AC working ground: Its main purpose is to ensure personal safety and equipment safety. Since the neutral line of the AC power supply line is grounded, when one phase leaks or short-circuits to ground, that phase will generate a large short-circuit current. This short-circuit current will trigger the protection device to operate, thereby avoiding the occurrence of accidents. (2) Safety protection ground: Safety protection ground usually exists between the metal casing and the earth, such as the grounding of metal chassis and cabinets. Its purpose is to prevent the metal casing from becoming electrified due to distributed impedance or power leakage, which may cause harm to equipment and people. (3) DC system ground: DC systems usually supply power to microelectronic systems. In order to ensure that the microelectronic system can work normally without interference, DC grounding is an important aspect that must be considered. DC grounding systems are usually divided into two categories: completely floating DC grounding systems and DC grounding systems connected to the earth. Floating DC grounding is widely used in power plants, substations and small and medium-sized computer rooms. Its design is to make the DC ground completely floating and not connected to any grounding system. DC grounding is widely used in the telecommunications field and large computer rooms. For example, the power supply of the program-controlled switch is -48V, which means that the positive terminal of the DC output of the power supply is connected to the ground and outputs -48V DC power relative to the ground. (4) Lightning protection grounding: Lightning protection grounding is used to prevent the huge damage caused by lightning strikes. Its grounding point must be separated from any other grounding point. 3.8 Grounding system of monitoring center computer room The monitoring center computer room must fully implement the following four grounding systems. (1) Lightning protection grounding system Since the street light building roof has already installed lightning protection facilities, the computer room itself will not install a lightning protection grounding system again. (2) AC working grounding This AC working grounding is divided into several groups. Among them, the computer system, large screen, etc. are grounded separately. Other power equipment, such as UPS, air conditioner AC neutral point should be grounded independently according to electrical specifications. (3) Safety protection grounding This grounding system fixes the entire cabinet shell to the protective grounding wire. The computer shell is grounded by connecting to the cabinet shell. The control cabinet and screen wall are all made of metal. The router, interface converter and other equipment are installed inside the cabinet, which can effectively overcome the problems of electrostatic induction and electromagnetic interference. The safety protection ground can be connected to the AC working ground of the computer system and then buried underground. The grounding resistance should be less than 10 ohms. In some instruments and equipment, the chassis and AC working ground are already connected (usually through a resistor of a few ohms, such as an oscilloscope), so there is no need to install the safety protection ground again. (4) DC grounding system The DC equipment used in the system is less and all are small equipment, so all of them can be floating DC ground. 3.9 Street light sub-control point grounding system Although the grounding system of the street light sub-control point is simpler, it actually includes the above four grounding systems. (1) Lightning protection grounding system The street light sub-control point room (or control box) has already considered the lightning protection grounding system, so the lightning protection grounding system will not be considered again this time. (2) AC working ground The original street light sub-control point room has already considered the AC working grounding problem, so the AC grounding system will not be installed again this time. (3) Safety protection grounding of the data acquisition unit's chassis grounding can effectively overcome the hazards caused by leakage, electrostatic induction and electromagnetic interference, and ensure the normal operation of the data acquisition control circuit inside the chassis. (4) DC working grounding The DC system here mainly refers to the data acquisition control board and its DC power supply. Since it is a miniature DC system, we adopt the floating DC ground method. When necessary, connect the protective ground of its communication lines (RS485, RS232) to the chassis of the data acquisition unit to prevent strong electrostatic interference from damaging the communication interface of the data acquisition unit. The biggest advantage of floating DC ground is that even if a connection accident occurs between the DC system and the AC system, as long as there is no multi-point connection, the strong current of the AC system will not damage the DC system. [b]IV. Functions of the street light monitoring system[/b] It can display the working status and operating parameters of all monitored objects within its monitoring range. Using the functions provided by the monitoring system, it can generate various statistical data, charts, shift handover logs, repair work orders, etc. The production management system uses a geographic information system as a graphical interface to realize the comprehensive operation management of the daily work of the street light system. It features functions such as operation management, statistics, fault management, report statistics, network interconnection, electricity cost management, maintenance management, material management, personnel management, and new/renovation design. It supports voice query, remote telephone voice alarm, and remote SMS alarm functions. Alarm Management: Alarm Levels: A. Emergency Alarm: Alarms that have already or are about to endanger equipment and communication security and must be handled immediately. B. Normal Alarm: Alarms that may seriously affect equipment and communication security and need to be handled as soon as possible. C. Pre-alarm: Alarms that may affect equipment and communication security and need to be scheduled for handling. Alarm Function Requirements: Alarm Threshold Setting: Set by the system administrator according to the site conditions. Alarm limits are divided into pre-alarm limits, normal alarm limits, and emergency alarm limits. a. Regardless of the monitoring system's current screen, alarms are automatically prompted, and alarm information is displayed and printed. All alarms use visual and audible alarm signals; b. Level 3 alarm signals use three different display colors and alarm sounds (or voice); c. Alarm confirmation function: After an alarm occurs, the operator can press the confirmation key on any screen to turn off the audible alarm sound, but not turn off the flashing lights. After the fault is cleared, the original state is restored. d. In the event of an emergency alarm, an alarm message is automatically sent to relevant personnel via the telephone network (pager, telephone, mobile phone). The alarm has a voice prompt, telling relevant personnel the name, location, time, and level of the alarm; after the fault is cleared, the audible and visual alarm is automatically cleared, and an alarm clearance message is automatically sent to relevant personnel via the telephone network. The configuration management monitoring system has configuration management functions. When operators change, add, or delete monitored objects in the system or adjust system parameters, users can complete the system configuration by changing the system configuration file. The security management system has comprehensive operation management functions. To ensure system security, a password must be entered when using certain functions. Access to the system is only allowed after system confirmation. The operation passwords have different levels to restrict the scope of operation for different personnel. All monitored devices have operation records, including the operator, the operated device, the operation date, and the time. The system should have query and statistical functions for these operation records. To achieve absolute security in controlling the sub-control points and eliminate the vulnerability of using similar software to access them, we adopted a dynamic encryption method. This means that the monitoring center and sub-control points periodically and automatically change the passwords for internal data exchange. This prevents even the operator from using software not originally provided with the monitoring station for control operations. The software is developed using dynamic encryption, effectively implementing four layers of protection at the sub-control points: IP address, data acquisition device communication address, administrator password, and automatic dynamic password. With these four layers of password protection, any operation at the sub-control points can be guaranteed to be foolproof. Even the manufacturer of the monitoring system, outside the street light management office's monitoring network, cannot control the sub-control points (data browsing is not protected by dynamic passwords). The sub-control point function collects the operating parameters and working status of the monitored devices in real time, collects fault alarm information, and sends it to the monitoring host (for detailed monitoring content, see the chapter "Sub-control Point Composition"). It receives and executes monitoring and control commands from the monitoring host in real time. It stores historical data from each device in real time and manages dedicated equipment. Each sub-control point has a backup battery, allowing it to continue operating for a period after a power outage. During this time, it can send relevant important information to the monitoring center for analysis. In the event of a monitoring center failure, the sub-control points can automatically record operating data and control the normal operation of equipment according to preset time intervals (e.g., timed light switching). The monitoring center calculates the accurate daily light switching times based on time curves (seasonal changes), enabling automatic (or remote) group switching on/off of all sub-control points; automatic (or remote) group switching on/off of a group of sub-control points; and automatic (or remote) switching on/off of individual sub-control points. Since colored light control is often unpredictable, in addition to remote control switching, a one-week control schedule can be preset. The system also includes information query, statistics, and printing functions. It monitors the working status and operating parameters of each sub-control point in real time and receives fault alarm information. As needed, it queries various monitoring data and alarm information collected by the sub-control points and displays or prints them out. Real-time monitoring of the working status of each sub-control point. Measurement and control commands can be issued through the data acquisition controller, and the security of operation is ensured by strict access control. It has statistical and custom report functions and can generate the following statistical reports and curves: (1) Daily, monthly and annual alarm statistics reports; (2) Daily, monthly and annual operation statistics reports; (3) Daily, monthly and annual monitoring data statistics reports; (4) Daily, monthly and annual equipment load curves; (5) Daily, monthly and annual total power consumption curves; (6) Equipment operating parameters or curves for any day; (7) Reports customized by users according to actual needs. (8) It has a file archiving function. The archived files (daily, monthly and annual alarm files and monitoring data files) can be saved on the hard disk for one year and then automatically imported into external storage. The information printing function has: (1) Immediate printing when an alarm occurs; (2) Timed printing according to management needs; (3) Screen copy printing; (4) Printing information is displayed on the screen. The printed content includes: a. Alarm reports; b. Daily, monthly, and yearly alarm and monitoring data statistical reports and custom reports; c. All monitoring parameters; d. Line graphs, histograms, etc. It features color graphic display for alarm querying and reporting, alarm level settings, and user operation password levels. The system allows for layer-by-layer expansion on a specified field operation flowchart, ultimately pinpointing the fault to a specific device (such as a transformer), while visually displaying the measuring points and alarm data that caused the fault. The main software interface is a city electronic map, with all sub-control points marked on the map. When a fault occurs, the sub-control point changes to an alarm color (usually red) and begins to flash. Clicking on a sub-control point displays a simulation diagram of that point, showing the transformer, control box, and other equipment at the sub-control point. Alarm dots flash on the affected equipment until the fault is cleared. The system can forward emergency alarm information and report data requested by the higher-level monitoring center in real time. The monitoring center periodically sends clock calibration commands to the data acquisition units at the sub-control points (used to correct the time of the self-controlled streetlights at the sub-control points). It has the function of connecting to an external large-screen projection display or electronic display screen. In case of an alarm, it can automatically send a remote voice alarm to maintenance personnel via telephone or mobile phone. In case of an alarm, it can also send alarm information to maintenance personnel's mobile phones via SMS via GSM modem. Maintenance personnel can check the operating status of the streetlight equipment and the monitoring system via telephone. [b]Summary[/b] With the development of the times and the accelerating pace of urban modernization, the demand for urban road lighting and urban beautification projects is increasing, while the contradiction between energy supply and demand is becoming increasingly prominent, and the requirements for energy conservation, green lighting, and other aspects are becoming more urgent and demanding. The traditional methods of manual and clock-controlled urban lighting systems can no longer meet the requirements. How to fully utilize high-tech means to solve the above contradictions has become a new and urgent issue in the current lighting control field. As one of the hallmarks of urban modernization, the automated control and intelligent management of urban road lighting brings significant economic and social benefits, and its promotion and implementation will be an important part of municipal engineering construction. Edited by: He Shiping