Video door phones put eyes and a voice at the entrance: outdoor video intercoms that let staff see and speak with a visitor before the door opens, keypad models that combine entry codes with the camera, and IP-based units that ring a desk phone, console, or mobile client anywhere on the network. For schools, offices, and secure facilities, controlled entry starts with knowing who is asking.
Plan them as network devices: IP intercoms integrate with the phone system or a monitoring station, so confirm compatibility with the platform that will answer the call, and plan power - typically Power over Ethernet - to the door. Outdoor units need ratings for the weather and the vandal exposure of the mounting point. The door release is its own circuit; coordinate the intercom's relay with the lock hardware it will trigger. One intercom platform across buildings keeps answering procedures uniform. COLAMCO supplies video intercoms and door-entry hardware for business, government, and education entrances.