The terms Anycast and Unicast, which are phonetically close, often lead to confusion. The difference between Anycast and Unicast is to know. In this article, I will once again break the vagueness and explain clearly what the difference is between Anycast and Unicast.
Unicast
As I explained in my article on the difference between Unicast, Multicast and Broadcast, the term unicast defines a point-to-point network connection, i.e. a one-to-one communication method.
So unicast means communicating between two computers each identified by a unique network address. The data packets are routed on the network according to the recipient’s address “encapsulated” in the transmitted frame. Normally, only the recipient intercepts and decodes the packet addressed to him.
However, it should be noted that Unicast is also used as a routing technique on the Internet. It allows data to be redirected to a computer host whose IP address and location are known in advance.
The diagram below illustrates the Unicast communication method:
Anycast
As for Anycast, it is therefore an addressing and routing technique that allows data to be redirected to the “closest” or “most efficient” computer server, depending on the routing policy.
Just as in Broadcast and Multicast, in Anycast there is also a “one-to-many” association between network addresses and endpoints: each destination address identifies a set of end receivers, but only one of them is chosen to receive the information at a given time for a given transmitter.
The diagram below illustrates the Anycast addressing and routing technique:
Difference between Anycast and Unicast
| Anycast | Unicast |
| It can be said that it is also a one-to-many communication method , but only one receives | It is a one-to-one communication method. |
| Slower process. | Very fast process. |
| One IP address, multiple servers, multiple locations | An IP address, a server, a location |
| A robust and distributed solution | A simple and commonly used architecture |
