Literally, remote monitoring can be divided into two parts: supervision and control, in which "supervision" refers to obtaining information mainly through the network; while "control" refers to the method of operating the remote computer through the network, restarting and shutting down the remote computer, and also includes the daily setting of the remote computer. Basic introduction Chinese name: composition of remote monitoring: supervision and control: divide the daily operation fields of remote computers into two fields: computer field and video monitoring field, computer field, video monitoring field, working principle, substation acquisition end, collection end composition, collection end function, monitoring center, composition and function, monitoring status, system functions, system advantages, technical problems and system development. Both computer field and video monitoring field have the saying of remote monitoring, but the meaning is completely different. Literally, remote monitoring in the computer field can be divided into two parts: monitoring and control, in which monitoring means remote monitoring, which can be divided into two parts: one is monitoring the environment, and the other is monitoring the computer system and network equipment. In any case, remote monitoring means mainly obtaining information through the network; while "control" means remote control, which refers to the method of operating remote computers through the network, and it not only includes remote monitoring. The function of remote boot can also be realized through the cooperation of hardware. In a word, if you want to completely control the remote computer, you should be able to monitor it first, that is, you can see the screen display of the computer, and then you can talk about "control". Remote control must combine "supervision" with "control", so we usually refer to this kind of remote control in general. In addition, for network administrators, remote control also includes the control of network devices. Nowadays, most network devices support Tel, and even remotely manage them by Web, which is also a remote control method. In the field of video surveillance, remote monitoring in the field of video surveillance refers to connecting video surveillance equipment to the Internet, so as to watch remote video images through terminal equipment such as computers or mobile phones. There are many access methods, such as connection port mapping and access through ip address; Watch through domain name resolution. Working Principle For the field of video surveillance, the general working principle is as follows. Firstly, the video signals from all cameras are input to the video acquisition terminal, and then the video acquisition terminal converts the video signals into digital images with 25 frames/second through the image compression algorithm, and forwards the compressed audio and video data streams to the video monitoring center through the network; Finally, the monitoring computer of the video monitoring center decompresses the received image and sound data from the front end and monitors it in real time through the computer display screen and sound card. When an alarm occurs, the alarm decoder will be linked with the alarm output device, and the alarm signal will be input to the video terminal through the alarm decoder and transmitted to the monitoring center. After receiving the alarm signal, the video server of the monitoring center will immediately send out sound signals, record alarm events, and perform alarm operations such as hard disk video recording. Control signals such as camera control and protection are transmitted downstream. The monitoring center monitors the host computer to send out various control signals. After receiving the control signals, the video acquisition terminal directly controls the camera through the Yuntai lens controller or completes the protection operation. The system adopts the technology of hardware compression and software decompression, and the remote video monitoring function can be realized by adding corresponding software to the computer terminals of relevant departments or through the Web function of IE browser that comes with Windows, and it is set as a video monitoring workstation. Network communication adopts TCP/IP and Multicast technology, which maximizes the transmission performance and bandwidth of the network and avoids network congestion. The remote video monitoring system consists of the system substation and the main station of the dispatching center. The sub-stations of the system are set in subordinate coal mines, power plants, substations and other places that need to be monitored. They are mainly composed of video acquisition terminals, computer network connection equipment, cameras, alarm probes, alarm decoders, etc., and are responsible for the collection and digitization of audio and video signals and alarm signals, and realize the video/alarm information transmission and remote monitoring between stations and the dispatching center by using the existing computer network. The main station of monitoring and dispatching center is mainly composed of video management server, browser, computer network connection equipment, remote monitoring and video server software. The monitoring center can manage multiple acquisition stations through the network, and can switch and control to any monitoring point to implement overall monitoring, so as to realize video monitoring of the whole area. Through the network, it can not only browse the live video of each monitoring point in real time, but also remotely access and download the video files of the collection station, and can also record in the monitoring center. Remote video monitoring system can generally adapt to different communication networks, which can be Ethernet, E1, wireless local area network or other transmission channels. The video acquisition terminal at the acquisition end of the substation provides video and audio input/output interfaces, which are respectively connected to the video output of the camera or the multi-picture processor, the pickup and the sound box; Generally, several interfaces are provided to connect with monitoring terminals and servers; It mainly realizes the collection and compression of video and audio signals, and transmits the compressed data to the monitoring center through the network. The acquisition end consists of 1. Video acquisition terminal 2. Picture splitter 3. Integrated camera or other cameras 4. Various alarm sensors and alarm devices 5. Alarm decoder 6. Yuntai and Yuntai decoder acquisition end functions 1. Image acquisition, recording and remote transmission; 2. Collect all kinds of alarm signals to realize alarm linkage and transmit them to the monitoring center of centralized control station; 3. Control the movements of the pan/tilt and the lens; 4. Control the matrix switcher to switch video images; 5. Receiving remote control commands to control the pan-tilt rotation, lens movement and alarm equipment output. The monitoring center is composed of central image processing server, image monitoring terminal, image processing software and remote video monitoring/networking alarm software, which is used to receive images transmitted from the site and alarm signals, prompting security personnel to take various measures. At the same time, remote control matrix, camera, pan-tilt and remote linkage control can be realized, and remote video file downloading, image retrieval and digital video playback are also feasible. The central image management server is used to manage the transmission and storage of images. The system management database, system management software and monitoring terminal module are installed on the management server, which plays a role in managing and serving the whole system. Monitoring function of monitoring terminal 1. Receiving video digital data from the acquisition station, playing back and forwarding it in real time; 2. Remote control can be realized; 3. Receiving the alarm signals from each acquisition station and transmitting them to the management server; 4. Configure and store the configuration information of each acquisition workstation, and manage the system users and user permissions; 5. The console can send control commands to any acquisition station, such as pan-tilt action and image switching. 6. Provide query and playback of historical video for the clients of console computer or dispatching center; 7. Display the image of any camera on the screen wall and switch it; 8. Provide WEB video streaming service for network users; 9. Realize the anti-interference design of cable wiring for conference TV function with the functional computer in the system. According to the special requirements of the system for flame retardant and fire prevention of cables, it is generally necessary to use all flame retardant prohibited cables, which can also play a good role in prohibiting high-voltage electromagnetic fields. In addition, outdoor buried cables are sheathed with hot-dip galvanized pipes, ordinary cables in cable trenches are sheathed with PVC pipes, and indoor cables are sheathed with PVC grooves, so that the system can completely eliminate the influence of some interference factors such as high electric field and high magnetic field on the system in high voltage environment. Composition and function system generally consists of three parts: front-end equipment, image processing and transmission equipment and network client. The front-end equipment consists of camera, pan/tilt, decoder, protective cover, bracket, alarm detector, pickup, etc., and is responsible for collecting video signals, audio signals and alarm signals; The image processing and transmission equipment in the system is a network video server, which is responsible for transmitting audio, video signals and alarm signals to remote clients through local area networks or wide area networks, and can also receive pan/tilt control signals and audio intercom signals transmitted by clients. Network client refers to the user terminal that needs remote monitoring of the network. It consists of computer (ordinary office computer or notebook computer) and client software. The client is mainly responsible for image display, video recording, playback and pan/tilt control. When the client carries out remote monitoring, it needs to enter the user name and password for authentication, and remote monitoring can be realized after authentication. There are two types of remote monitoring system for monitoring the status quo. One is that there is no on-site monitoring system at the production site, but the data is collected and sent directly to a remote computer for processing. This remote monitoring is not much different from the general on-site monitoring, except that the data transmission distance is farther than the on-site monitoring system, and the other parts are the same as the on-site monitoring system; The other is the coexistence of on-site monitoring and remote monitoring. Generally, the field bus technology is used to connect the sensors and monitoring devices distributed in various devices, thus entering the integrated unit stage from the discrete unit stage, and then the services of various management sites are connected by the local network, thus forming an intranet. Due to the establishment of the basic network information infrastructure, equipment monitoring and maintenance technology has entered the stage of integrated system, and basically realized the sharing of resources and information in a unit. The functions realized by remote control are as follows: acquisition and processing function: mainly to detect, sample and pre-process various analog or digital quantities in the production process, and output them in a certain form, such as printing reports, display screens and televisions, to provide detailed data for production personnel to help them analyze in order to understand the production situation; Supervision function: analyze, summarize, sort out and calculate the detected real-time data, as well as the instructions and input data issued by the production personnel in the production process, and store them as real-time data and historical data respectively; Management function: analyze working conditions, diagnose faults and predict dangerous situations by using existing effective data, images and reports, and give an alarm to faults and emergencies in the form of sound and light; Control function: information processing is carried out on the basis of detection, and control output is formed according to the control strategy decided in advance, which directly acts on the production process. The remote monitoring system based on B/S and C/S is a monitoring system with the network as the communication platform. Based on HTTP technology, it has the advantages of simplicity and high efficiency, and has become one of the most widely used information interaction platforms in the information network [2]. Using network communication technology, Socket technology, data acquisition technology and object-oriented software technology, the system management, user management, equipment monitoring data display and alarm modules of the whole system are realized. Its advantage is that the existing local network resources and wide area network resources are fully utilized, and the real-time acquisition and real-time control of information are the center, so as to realize the comprehensive and integrated management of information, resources and tasks. For example, the monitoring system provides the running status of the equipment to the server, and the server sends it to each node client, so that the staff can know the working status and running status of the whole system at the client side (generally remote). To put it simply, for enterprises, it is to make full use of modern technology to solve the problems of real-time data collection, transmission and processing and real-time control. It is these advantages that enable it to develop rapidly. With the continuous development of network technology, remote monitoring will be more applied to the management of enterprise production process. Professional technicians can manage and maintain the production process through the Internet, optimize the production process, improve the availability of equipment, and ultimately reduce production costs and improve efficiency. Advantages of the system: With the help of remote monitoring, the intra-enterprise information network can be effectively connected with the control network, and the production and operation situation can be grasped at any time, and the production and operation situation can be closely combined with the management strategy of the enterprise, so as to realize the comprehensive automation of the enterprise and establish the monitoring Intra and online knowledge resource database within the network. Through remote monitoring, real-time collection and rapid concentration of field operation data can be realized, and field monitoring data can be obtained, which provides a material basis for remote fault diagnosis technology. Through remote monitoring, technicians can monitor and control the operation status and various parameters of production systems and field equipment without visiting the site or harsh environment, so that professionally trained personnel can. Virtual. It appears in many monitoring sites, and it is convenient to use the rich local software and hardware resources to carry out advanced process control on remote objects, so as to maintain the normal operation of equipment, thus reducing the number of staff on duty, and finally achieving the goal of reducing staff and increasing efficiency [3]. More and more enterprise groups are developing across regions. Using network technology to realize remote monitoring is of great significance for enterprises to reduce production costs, improve labor productivity, improve the scientific and technological content of their products, and enhance their comprehensive competitiveness. Technical problems With the rapid development of network technology and the expansion of monitoring scope, the monitoring system has changed from single-machine monitoring to network monitoring, but there are still some problems. First of all, the problem of insufficient network communication technology. Network communication technology is the most critical technology in remote monitoring technology. However, Socket technology, even FTP or Email, is generally used in network communication. These technologies have great shortcomings in terms of data transmission, programming flexibility and security, especially for data acquisition of multiple endpoints on site, which will greatly increase the complexity of programming and cannot meet the needs of remote monitoring technology for network communication. Secondly, the coexistence of multiple structures in network communication. Most of the remote monitoring systems are complex in structure and long in distribution distance, and there are also different problems in different local networks, different platforms, and even operating platforms and programming languages in the same local network, which requires the integration of different platforms in the network to achieve communication between them, and these problems are difficult to solve by traditional methods. System development Video surveillance system has been developed for just over twenty years, and the network video surveillance, which is in the ascendant of analog monitoring and digital monitoring, has undergone earth-shaking changes. Today, with the gradual unification of IP technology around the world, it is necessary for us to re-understand the development history of video surveillance system. From the technical point of view, the development of video surveillance system is divided into the first generation analog video surveillance system (CCTV), the second generation digital video surveillance system (DVR) based on "PC+ multimedia card", and the third generation video surveillance system (IPVS) based entirely on IP network. The first generation of video surveillance: the traditional analog closed-circuit monitoring system (CCTV) relies on special equipment such as cameras, cables, video recorders and monitors. For example, a video camera outputs a video signal through a dedicated coaxial cable. Cables are connected to special analog video equipment, such as video picture splitter, matrix, switcher, video cassette recorder (VC)