04 Try it yourself Interactive
The scene from section 02, one press at a time. The box in the middle is what is on the wire; underneath it, the addressing box shows all six fields of that packet, with the field the narration is talking about picked out in indigo. Below that, the client's configuration fills in as it is granted. Eight steps take you through DISCOVER, both OFFERs, the REQUEST, the ACK, the moment the address is actually usable, and then the renewal at T1, so you can see for yourself that the renewal is a unicast and the four before it were not. No server answers runs the same client on a segment with no DHCP server and no relay, and ends where a great many support tickets end, on a 169.254 address. The lease length is yours to change and T1 and T2 are recomputed from it. Nothing plays on its own: Next, Back and Reset, or the arrow keys.