Which component of a network changes the broadcast domain?

A router is the component of a network that changes the broadcast domain. This is because routers operate at the network layer (Layer 3) of the OSI model and are responsible for routing data packets between different networks. When a router receives a broadcast frame, it will not forward that frame to other interfaces; instead, it isolates the broadcasts within individual networks.

In contrast, a switch operates at the data link layer and is primarily used to create collision domains while extending the size of the broadcast domain, since it forwards broadcast frames to all ports within the same network. Hubs and repeaters, being Layer 1 devices, simply transmit signals across all connected devices and do not segment networks or create separate broadcast domains.

By understanding how routers segment broadcast domains, you can better grasp how data travels across diverse networks and the importance of managing traffic for efficient network performance.