1. High Stability: Based on pure embedded technology, use high-speed DSP-based digital media processor, realize Audio&Video coding and network transmission, Surveillance front -end does not need the support of PC or PC-based industrial computer, has high stability. Equipment Installation is simple and flexible.
2. Low Cost: The network is established based on ADSL dialling-up network with easy maintenance, cheap communication fee and low operating cost.
3. Expandability: The whole surveillance system does not limit the number of users who want to share information. The system can be expanded easily and can add or delete surveillance spots flexibly.
4. Easy to Manage: Realize unified dispatching and centralized management, remote control and parameter settings of front-end device, and terminal software upgrade via Central Management Software in the management centre.

System Configuration
The whole system is composed of two components: Front-end Surveillance Device and General Surveillance Centre. Front-end Surveillance Device realize distributed Audio & Video access, connect the nearest surveillance video to network through HangHe HH500X series of Network Video Encoders. General Surveillance Centre implements centralized management, controls and dispatches video connection and access service through special Video Servers.

Configuration of Surveillance Spots
Surveillance Spots are mainly composed of HH500X series of Network Video Encoders, PTZ/PTZ Controllers,Cameras and Alarm Devices. Under the Central Video Server's control, Network Video Encoders compress and process surveillance video signal in real time and then transmit the signal through the nearest network. They are also well prepared to receive control commands from image client ends or image console to implement video switch, operation control of PTZ/Camera and Zoom Lens as well as setting of local parameters.

General Surveillance Centre
General Surveillance Centre is mainly composed of Video Surveillance Server, Video Transition Server, Video Storage Server, HH6104 Decoding Card,HH5104 Network Video Decoder,etc. The Video Surveillance Server is mainly used to manage and control front-end surveillance video in the whole system (including image switch, PTZ/Tilt control and Zoom Lens control of surveillance spots), and can also be used to decoding multi channels network video via built-in HH6104 decoding card to implement real-time video display and surveillance on TV wall. Video Transition Server is mainly used to receive and transit video streaming data and realize multi-level cascade and expansion of system. Video Storage Server is used to implement central storage of all surveillance video as well as search and playback of video data. The system can divide different surveillance spots into several different access levels according types of users. Users with highest priority have authorization enough to control video image, and users with lower priority only allowed to see the image, and uses with higher priority can override control rights of the images.

Application of Networking
This solution is based on ADSL dialling-up network, can transmit high quality H.264 images at a speed of 25 frames per second without delay more than 300 milliseconds.