Unicast vs Multicast vs Broadcast-Difference between Unicast,Multicast,Broadcast
This page compares Unicast vs Multicast vs Broadcast and mentions difference between Unicast transmission, Multicast transmission and Broadcast transmission and address types.
• The term unicast refers to "one to one".
• The ip addresses which are not used for multicast and broadcast are used for unicast transmission.
• In unicast mode, transmission happens from host to host i.e. one to one. This will not incur any traffic burden on the LAN.
• The devices such as switch uses unicast mode of transmission.
• The term multicast refers to "one to selected group of members".
• IANA controls assignment of multicast addresses. They have assigned IPv4 class D addresses for this application. Hence addresses in range from 126.96.36.199 to 188.8.131.52 are used as IP multicast addresses.
• The protocols such as IGMP, MPLS (uses labels instead of addresses) uses multicast transmission concept.
• In multicast mode, transmission happens from one host machine to selected group of host machines.
• The term broadcast refers to "one to all".
• The ipv4 address 255.255.255.255 is used as broadcast address. IPv6 does not implement this, instead it uses multicast assignment of addresses.
• In broadcast mode, transmission happens from one host to all the other hosts connected on the LAN. The devices such as bridge uses this. The protocol such as ARP implement this, in order to know MAC address for the corresponding IP address of the host machine. ARP does ip address to mac address translation. RARP does the reverse.