The calculation of level of service (capacity of the roundabout) is based on an accelerated virtualization circulation process in a roundabout or roundabout. Iran vehicles moving at the right speed. Comply with traffic rules and act as regular drivers, ie adequately know the path to follow. Furthermore, heavy vehicles have a slower rate and are slower to react, as would be expected. Sets the service level values ​​(A to F) as the delay in the gazebo. As service level criteria will be used the