Unicast Address

What Does Unicast Address Mean?

A unicast address is an address that identifies a unique node on a network. Unicast addressing is available in IPv4 and IPv6 and typically refers to a single sender or a single receiver, although it can be used in both sending and receiving.


A unicast address packet is transferred to a network node, which includes an interface address. The unicast address is then inserted into the destination’s packet header, which is sent to the network device destination.

Unicast is the most common form of IP addressing.

Techopedia Explains Unicast Address

A unicast address identifies a network device, such as a workstation or a server. A unicast address on a local area network (LAN) contains a subnet prefix and an interface ID.

A unicast address is used in the following instances:

  • Unspecified Interface Address: A unicast address with a value of 0:0:0:0:0:0:0:0 is used in the absence of an unspecified interface address.
  • Loopback Address: A unicast address with a value of 0:0:0:0:0:0:0:1 is used to specify a loopback address used to redirect the packets to their source.

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