ARP , RARP & Proxy ARP

ARP = Address Resolution Protocol
RARP = Reverse Address Resolution Protocol

ARP
--------
- I know my destination IP address but i don't know it's MAC address
- Map known layer 3 destination address to unknown destination layer 2 address.

RARP
--------
- I know my source MAC address but i don't know my IP address
- DHCP server will give IP address to my host

Reference ::
http://www.youtube.com/watch?v=b7gv09B_80A