Client usage of DHCP is provided by the dhcpagent daemon. When ipadm is used to create a DHCP address object, or when ipadm identifies an interface that has been configured to receive its network configuration from DHCP, dhcpagent is started to manage an address on that interface.
For more information, see the /etc/default/dhcpagent information in the FILES section of dhcpagent(1M).