Once the vDHCP assigned a IP to the vBRG_emulator, the vBRE_Emulator needs to create the NAT rule to ensure the control plane traffics sending from SDNC could be sent to the Honeycomb which hooks to a tap port connected to the VPP. The forwarding rule could be done by using src ip of the SDNC, and the static ARP rule could be done to the kernel and VPP's tap ports, but the NAT rule needs to specify the WAN IP so has to be done by automatically when VPP acquires a IP from the vDHCP.