The roadwarriors carol and dave set up a connection each to gateway moon and request a virtual IP via the IKEv2 configuration payload by using the leftsourceip=%config parameter. The dhcp plugin on gateway moon then requests an IP address and DNS server information from DHCP server venus using the DHCP protocol. The IP addresses are assigned dynamically by venus from the pool 10.1.0.50..10.1.0.60 so that carol and dave become full members of the subnet 10.1.0.0/16 hidden behind gateway moon. And this thanks to the farp plugin through which moon acts as a proxy for ARP requests e.g. from alice who wants to ping carol and dave.