DHCP options are various types of network configuration information that the DHCP client can receive from the DHCP server. The Branch Gateway supports all DHCP options. The most common options used for IP phones are listed in Common user-configurable DHCP options. Some options are configured with specific CLI commands that are also listed in Common user-configurable DHCP options. Options 0, 50, 51, 52, 53, 54, 55, 56, and 255 are not configurable.