Success of a custom built surveillance system mostly depends on initial stage when you design it. A diagram of your surveillance system would be the starting point of your design. it helps outline the future functionality and performance of the system. When a list of the surveillance system components is defined in a drawing, it is easy to work on each part of the design.
The diagram represents POE IP camera custom built surveillance system. It can be used as a boilerplate for designing of any surveillance system.
Your cameras are driving the design of the entire system. IP cameras are chosen as they have better quality comparing with analog ones. Also, those cameras are generic ones and they can be plugged in different Network Video Recorders (NVR). Moreover, cameras are wired with Power Over Ethernet (POE). It helps reduce number of wires coming to cameras combining connectivity and power cables together. Wired cameras are more reliable in terms of connection and volume of transmitted data than WiFi ones. Getting higher resolution data stream is not a problem for wired cameras whereas WiFi cameras can reduce video quality because of weak signal. TrenNet cameras are generic commercial grade ones.
Network Video Recorder (NVR) is another critical component. Cameras and NVR have to compatible with each other. NVR collects video from cameras, converts video into compressed format and stores digital data. It is better to set up one device which serves as NVR and storage, for example, Synology NAS or QNAP NAS. They include requested hardware along with Surveillance Station software.
POE switch connects cameras to a home network and supplies power to cameras. Also, home users can have wired connection to home network as an extra feature. TrendNet POE switch can do good job.
WiFi router manages home network, provides access of wired and WiFi users to cameras, and exposes cameras to outside world.
The last important component is Uninterruptible Power Supply (UPS). Power outages can break down your surveillance system.