DHCP: How it works

• Use the network to obtain an IP address

• • But you need an IP address to use the network!
  • Solution: Ultimate broadcast address, 255.255.255.255
  • Routers will not pass packets with this target

• dhcpd listens for broadcasts to 255.255.255.255

• Replies with an offer of an IP address lease

• • Along with other network information

• RFC 2131 for IPv4, RFC 3315 for IPv6