Introduction
As in hydraulics, where the maximum capacity of a pipe is its diameter. When the traffic demand does not exceed the supply, the traffic is continuous and fluid, but if it exceeds the supply, an accumulation is created at the weak point.
Access control principle
The principle of access control is to artificially reduce the maximum supply of vehicles through the installation of a "tap light", which makes it possible to regulate the flow of vehicles entering the core of the city according to the capacity of the internal network.