unicast
also: unicast transmission, one-to-one communication
A network transmission sent from one source address to a single destination address. The opposite of broadcast or multicast.
Unicast is the standard point-to-point communication method in networking where a packet travels from one sender to exactly one recipient. Each device has its own unique address, and data is routed only to that specific address.
In contrast to broadcast (one sender to all devices on a network) or multicast (one sender to a group of interested devices), unicast is the most common and efficient method for individual device communication. For example, when you visit a website, your browser sends a unicast request to a specific server's IP address, and that server sends unicast responses back only to your machine.
Most everyday internet traffic is unicast: email, web browsing, SSH connections, and file transfers all use unicast addressing. This ensures privacy and prevents unnecessary network congestion by limiting delivery to the intended recipient only.