1. When the user is on the ServiceCenter, create a network, and specify CIDR and start the DHCP function (external_api plane).
2. After receiving the ServiceCenter, request the network service (Internal_base plane) from Neutron-Server through RestAPI.
3. When Neutron-Server receives it, it will notify dhcp-agent to implement DHCP function via rabbitmq in rpc mode, and will inform dhcp-agnet CIDR and other information (Internal_base plane).
4. dhcp-agent will call the local dhcp-driver, dhcp-driver will pass rabbitmq as rpc and Neutron will create dhcp port (Internal_base plane)
5. Neutron-Server will notify the ovs-agent implementing the DHCP node to create a Layer 2 network device belonging to the network tap (Internal_base plane)
6. dhcp-driver configures the dnsmasq configuration file and starts the dnsmasp process call configuration file and listens for the tap device created earlier
