The "evolution history" of smart intercom has gone through from voice intercom to visual intercom, from black and white intercom to color intercom, from single intercom terminal type to diversified terminal type, and gradually moving from resident type to cloud platform. Now, with the continuous development of the Internet, Internet of Things, cloud technology, etc., smart intercom is also playing an increasingly important role in the construction of smart parking systems.

As a transit place for vehicles when people travel, the parking lot requires high overall performance. The quick entry and exit, vehicle guidance, pick-up guidance, unmanned charging and other items in the smart parking lot system make the parking lot more efficient. Its convenience and reliability make it easier to manage the increasing number of cars.

However, the parking lot system only aimed at the management of vehicles. The parking lot is a small vault, especially for large parking lots. This will inevitably lead to some criminals peeping or public security incident happening in the parking lot. At this time, the parking system's insufficiency of the safety of life and property is reflected. How can we stop this happening at this time? Due to the large number of vehicles in and out, the parking lot system continues to operate. Sometimes, during the peak period, it is hard to avoid the increase of the system workload, which leading to system failure and misleading phenomenon. If the barrier cannot be opened when a car entering or exiting; or the system in the parking lot has guidance errors or the system fails. When these things happened, the car owner fell into a state of no one to guide, and the scene will be chaotic.

The benefits of the smart parking lot system for people are beyond words, but its communication limitations make this powerful system an "island" when there is a problem.

If there is a suspicious person wandering in the parking lot, there must be a broadcasting system to broadcast the scene to clear the suspicious person. If the owner of the vehicle cannot open the barrier, the owner can use the call intercom system to contact the staff in time to solve problems. If there is a security incident in the parking lot, the monitoring system will automatically generate audio and video files and upload them automatically to make a strong evidence. A perfect smart parking lot system should not be an "island". In order to enable such an advanced system to serve people at any time and improve the protection of the owner's life and property, it should be able to interact with the outside world and conduct timely intercom calls.