[neutron] OpenStack Port Creation process

Hi,

I want to understand the Port Creation process in OpenStack.

1. What happens in the background when we create a Port with Security Groups? Does it create the port in the Control Plane level or is neutron involved in this?

2. How does the port obtain the IP address from DHCP and Who initiates this DHCP Process?

3. Is there any docs/links available for the same?

Thanks, Dhana