What is a "collision domain"?

A collision domain refers to a network segment where data packets can collide with one another during transmission. This occurs primarily in traditional Ethernet networks that utilize a hub or a shared medium for communication. In a collision domain, if two devices attempt to send data simultaneously, a collision occurs, leading to data loss and requiring the devices to retransmit their packets after a random backoff period.

In essence, the concept of a collision domain is crucial for understanding networking behavior in environments where shared bandwidth is in use. By limiting the size of a collision domain through the use of switches or routers, network performance can be significantly improved, as these devices create separate collision domains for each connected device or group of devices. This segregation minimizes the risk of collisions and enhances overall network efficiency and speed.