Unicasts, Broadcasts, and Multicasts

Question 1

What is a unicast?

Answer 1

When one station is sending information to another station.
1 station communicating with another station.
Examples include web surfing (1 device interacting with 1 web server), file transfers (1 device sending file to another).

Question 2

What is a broadcast?

Answer 2

When one station is communicating to everyone else at once.
One packet, received by everyone.
Examples include routing updates, ARP requests.

Question 3

What is a multicast?

Answer 3

When one station is sending information to many, but not all stations.
Compromise between broadcast and unicast.
Examples include multimedia delivery, stock exchanges.
Multicast is difficult to scale across large networks.