What Is Multicasting?

• A unicast packet is sent to a specific host

• A broadcast packet is sent to all reachable hosts within a certain scope

• • Local broadcast, directed broadcast, limited broadcast

• Multicasting refers to sending a packet to some, but not all, reachable hosts

• • Typically the hosts must request the reception of specific multicasts

• Why multicast?

• • More efficient use of bandwidth and host processing power

• Uses

• • Configuration
  • Service advertisements
  • Audio and video distribution
  • Gaming
  • Application-specific broadcasting