Many friends asked if the 100-channel monitoring needs to use the core switch? Speaking of the core switch, it is inevitable to think of the networking mode of the switch. How do networks of different sizes be networked? Before we understand switch networking, let's start with the monitoring installation.
Monitor installation and networking
Need equipment:
Network camera, hard disk recorder NVR (or ordinary PC plus client, suitable for ordinary users with desktop computers installed), switches (need to adjust according to the number of cameras and code rate, the supplier's recommendations can be used) hard disk, display , network cable, power sheathed cable, power adapter (or 12V DC switching power supply), camera bracket, cable crystal head.
Installation principle:
The front-end camera is previewed and stored by the network cable and the switch to transmit the captured video signal to the DVR in the background while the power supply is running normally. There are differences in the specific connection methods for monitoring system points. For the specific connection diagram, see the third step below.
installation steps:
In the first step, familiarize yourself with the products under the monitoring kit, determine the installation position and monitoring area of ​​the camera, and fix the camera to the building or pole frame through the camera bracket.
The second step is to determine the placement of the background device (DVR and display). The DVR is installed with the hard disk and placed, and the power supply is ready for the background device.
In the third step, after the front and rear ends are completed, wiring is required. (If the planning or plan is done in the early stage, this step is actually a priority, especially in the environment where the decoration is to be completed, the pipeline needs to be pre-buried) Divided into two parts:
First of all, to confirm the location of the switch, you need to connect each camera to the switch through the network cable, and also need to connect the network hard disk recorder (NVR) with the switch, in line with the principle of convenient routing and beautiful and safe, and in each Make a crystal head at both ends of the root line;
Secondly, the camera power supply line wiring, each camera needs a 12V / 1A or 2A power adapter, look at the construction environment or cost requirements, you can use a switching power supply instead (recommended a 12V/10A switching power supply do not bring more than 10 cameras , and so on), an additional power plug is required. In addition, depending on the number of points in the monitoring system, the connection method used is different.
Architecture 1, 1-8 points of small engineering
For small projects with 1-8 points, you can directly use the ordinary 100M switch to achieve network environment construction. If 2 megapixel IPC is used, the code stream is calculated at 4 Mbps, 8 cameras occupy 8*4=32M, and the actual utilization rate of 100 Mbps switch is 50%-70%, that is, 50-70M, which can satisfy 8 IPCs. Transmission requirements.
We can see that the core topology of the small network does not use the core switch.
Architecture 2, 9-50 points of small and medium-sized projects
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For small and medium-sized projects with 9-50 points, it is not enough to use only 100M switches. A higher-performance Layer 2 full Gigabit switch is needed for convergence to ensure smooth transmission of video information.
For example, with 2 megapixel IPC, the code stream is calculated at 4 Mbps, and 20 cameras occupy 4 M*20=80 M. If 10 cameras are connected to the 100 Mbps switch, then we need 2 access layer switches, then gather. Layer switches require a two-layer Gigabit switch.
　 Medium and large-scale projects with three or more structures
For medium and large projects with more than 50 points, a three-layer network architecture is required: the access layer, the aggregation layer, and the core layer. At the same time, due to the large number of points, the performance requirements of the core layer switches are relatively high. Generally, in this case, a three-layer full Gigabit core switch of a well-known manufacturer such as Huawei or Huawei is required.
The fourth step is to debug the camera. After the installation is completed and all the lines are connected, the camera is powered on. The network settings must be made on the network hard disk recorder (NVR), and the network camera is added. (The configuration methods of different manufacturers are different. ), after adding all the cameras, you will see the image, you can debug the camera angle, adjustable focus lens, etc. to the appropriate effect.
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