Video door phone or VDP system is like security to the homes.
The owner can decide who to enter their house. VDP system is fixed just outside the gate, so the visitor can press the bell in the VDP, then it will makes a call to the owner registered mobile application. Then he can attend the video call and can see who is outside the gate. And can also open the gate through the phone.
As VDP is connected to a POE switch where it is connected to the internet.
So the owner can access through the mobile