Dynamic Host Configuration Protocol, a protocol that allows a DHCP server to automatically set TCP/IP network configuration for a client computer. How does work DHCP? 1.Whenever a client computer boots up, it broadcasts a DHCPDISCOVER massage. it doesn't matter where the client is in airport, at home, in a desert, or in a jungle it would send this packet looking for a DHCP server. And the client has no idea if there is any DHCP server closeby therefore broadcast the only way you may notice the destination IP address is 255.255.255.255. DHCPDISCOVER packet simply says "Hello", is there any DHCP server out there? I want to connect the Internet." 2.supose there is a DHCP server close by and it hears the DHCPDISCOVER massage. the DHCP server responds with a DHCPOFFER massage. It is a broadcast UDP packet. It simply replies :"I hear you. I can lease you this IP address and this subnet mask, so that you can connect to the local network. ...