TCP/IP - Technical MCQs

Q1:

Which of the following describe the DHCP Discover message?
  1. It uses FF:FF:FF:FF:FF:FF as a layer 2 broadcast.
  2. It uses UDP as the Transport layer protocol.
  3. It uses TCP as the Transport layer protocol.
  4. It does not use a layer 2 destination address.

A 1 only

B 1 and 2

C 3 and 4

D 4 only

ANS:B - 1 and 2

A client that sends out a DHCP Discover message in order to receive an IP address sends out a broadcast at both layer 2 and layer 3. The layer 2 broadcast is all Fs in hex, or FF:FF:FF:FF:FF:FF. The layer 3 broadcast is 255.255.255.255, which means all networks and all hosts. DHCP is connectionless, which means it uses User Datagram Protocol (UDP) at the Transport layer, also called the Host-to-Host layer.