Transmission

• https://serverfault.com/questions/279482/what-is-the-difference-between-unicast-anycast-broadcast-and-multicast-traffic
• https://en.wikipedia.org/wiki/Routing#Delivery_schemes

LAN

• Types
  • Unicast
  • Multicast
  • Broadcast

Unicast

• Two network nodes directly talk to each other
• Examples
  • TCP/HTTP protocol

Broadcast

• https://www.youtube.com/watch?v=ZNXDbzaAM-I
• All nodes on the subnet will see all traffic
• Broadcast
  • Layer 2 feature in the Ethernet protocol
    • MAC address: FF:FF:FF:FF:FF:FF
  • Layer 3 feature in IPv4
    • IP address: 192.168.101.255 for subnet: 192.168.101.0/24
• Examples
  • ARP protocol: Layer-2 broadcast
  • NetBIOS protocol: Layer-3 broadcast

Multicast

• It is like a broadcast that can cross subnets
• Multicast
  • Layer-3 feature of IPv4 (optional)
  • Layer-3 feature of IPv6 (mandatory)
  • Address??
• Examples
  • Service Location Protocol (SLP)

Anycast

• advertise the same network in multiple spots of the Internet
• Nodes use a unicast connection to talk to your anycasted nodes.
• Pretty different from other *cast
• Examples
  • 6to4 IPv6 transition protocol
  • Google does Anycast with its search pages in some places
  • The Root DNS servers use Anycast for similar reasons

TYPE	ASSOCIATIONS	SCOPE	EXAMPLE
Unicast	1 to 1	Whole network	HTTP
Broadcast	1 to Many	Subnet	ARP
Multicast	One/Many to Many	Defined horizon	SLP
Anycast	Many to Few	Whole network	6to4