[Go0the0gophers]

dora is for:

Discover: first request broacasted by client in order to get lease (@ip and others configurations)

Offer: response bradcasted by server with the lease (@ip and others configurations)

Request: broacasted by the client in order to confirm the usage of this lease(from this server, others server can release other lease)

Ack: ack from server

[leshow]

Yup. Although, to be pedantic, the offer/ack is often unicast. Here's the relevant bit from the RFC.

> If the 'giaddr' field in a DHCP message from a client is non-zero, the server sends any return messages to the 'DHCP server' port on the BOOTP relay agent whose address appears in 'giaddr'. If the 'giaddr' field is zero and the 'ciaddr' field is nonzero, then the server unicasts DHCPOFFER and DHCPACK messages to the address in 'ciaddr'. If 'giaddr' is zero and 'ciaddr' is zero, and the broadcast bit is set, then the server broadcasts DHCPOFFER and DHCPACK messages to 0xffffffff. If the broadcast bit is not set and 'giaddr' is zero and 'ciaddr' is zero, then the server unicasts DHCPOFFER and DHCPACK messages to the client's hardware address and 'yiaddr' address. In all cases, when 'giaddr' is zero, the server broadcasts any DHCPNAK messages to 0xffffffff.