Urban network video surveillance systems have huge investments and complicated technologies. Therefore, it is very important to make an overall objective assessment of the system before construction. The basic features of the urban video surveillance and alarm networking system are the overall investment, high technical requirements, users involved, and many links (involving image acquisition, transmission, storage, management, and sharing). In general, the basic evaluation principles of the city video surveillance alarm networking system are: whether the system can meet the actual use requirements; whether the system can be managed and maintainable; whether the system has the ability to expand and upgrade; whether it can provide conditions for the upgrade of intelligent functions; Is it sustainable?

The technical evaluation of the system mainly includes 10 criteria:

1. Practicality. The system should take into account factors such as local environmental conditions, monitoring objects, monitoring methods, maintenance, and investment scales to meet the needs of the normal operation of urban video surveillance and alarm networking systems and social and public safety management.

2. Reliability and stability. The system should use mature technologies and reliable equipment, and have backup or redundancy measures for key equipment. The system software has maintenance support capabilities and strong fault tolerance and system recovery capabilities to ensure that the system runs as long as possible, and can be repaired or restored as soon as the system fails.

3. Extensibility. Should adopt the distributed system and the modular structure design, in order to meet the system scale expansion, the function expansion, the matching software upgrade demand. Users can expand or tailor the system as needed to provide sufficient flexibility.

4. Advancement and inheritance. The construction of urban video surveillance and alarm networking system is impossible to abandon the original simulation-based system. The proper approach is to include the original simulation system as far as possible on the premise of planning a fully digital system. The most ideal system is to be able to seamlessly connect between the two to form a complete city video image network monitoring.

5. Performance price ratio. The designer should reasonably set the system function, correctly configure the system and select the equipment. Under the premise of good grades of key equipment, the overall price of the system is guaranteed to be low, so that the system has a higher cost performance. The camera selection at the front end of the system and the level of the back-end software should be the focus of attention. If the number of lines of the front camera is lower than 460 lines, no matter how good the follow-up system is, it is impossible to ensure that the system has clear image effects. In some applications, advanced features such as wide dynamic range are also needed.

6. System upgrade and maintenance convenience. Due to the large scale of the system, the system software and core equipment should have automatic upgrade and maintenance functions. In addition, the city monitoring and alarming networking system consists of a number of complex systems, including networks, storage, operating systems, platform software, various front-end equipment, etc. Therefore, it is required that each subsystem should have a working log record, including all modules and core equipment of the system.

7. System management functions and ease of operation. Considering the scale and complexity of the networked system, the management software platform should have a good system architecture. The system core management and business management must be clearly separated to ensure that they meet different application requirements. Due to the large number of various management servers, storage and forwarding servers in the system, the network management functions of the system must be powerful. Otherwise, routine maintenance cannot be performed. The management and user interface provided by the system should be clear, concise and friendly, and the operation should be simple and convenient. Flexible, easy to learn and use, easy to manage and maintain.

8. The system supports secondary development capabilities. The number of cameras in a city’s surveillance alarm networking system is at least as many as hundreds, and as many as tens of thousands, so the sustainability of the platform must be considered. To achieve the goal of “video creation value” requires the system to have the conditions for secondary development, and only in this way can we ensure the full use of platform video resources.

9. The degree of security of the system. System security includes many aspects, among which the main purpose is to prevent the access of illegal users and devices. Therefore, in addition to different levels of authentication methods for different users (including administrators and users), it is also necessary to ensure that illegal devices cannot be accessed. Go to the system. Networked monitoring systems are most vulnerable to hackers and effective security protection measures should be taken to prevent the system from being illegally accessed, illegally attacked and infected by viruses. In addition, it is also necessary to prevent unsafe factors such as lightning, overload, power failure, electromagnetic interference, and man-made damage to provide comprehensive and effective security measures.

10. Compatibility and standardization. Compatibility is the key to interconnecting devices from many different manufacturers and protocols. The system should be able to effectively communicate and share data, as far as possible to achieve device or system compatibility and interoperability. The higher the degree of standardization of the system and the better the openness, the longer the life cycle of the system. Control protocols, transmission protocols, interface protocols, video/audio codec, and video/audio file formats, etc., should all comply with the requirements of the corresponding national or industry standards.