Which devices are responsible for creating large collision domains?

Hubs are devices that operate at the physical layer of the OSI model, meaning they do not filter data or manage traffic intelligently. When a hub receives a data packet, it broadcasts that packet to all connected devices within the network. This behavior causes all devices on the hub to share the same collision domain, which can lead to an increased likelihood of data collisions as multiple devices attempt to send data simultaneously.

In a network where a hub is used, whenever two devices try to communicate at the same time, a collision occurs, resulting in both devices needing to retransmit their data after a random backoff period. As the number of devices increases, the potential for collisions also rises, leading to inefficient communication and network congestion.

The other devices listed, such as switches, routers, and firewalls, operate differently. Switches create multiple collision domains by segmenting the network; they can intelligently send data only to the intended recipient, thus reducing the chance of collisions. Routers operate at the network layer and do not typically create collision domains but instead create broadcast domains. Firewalls are primarily used to filter traffic based on security rules and do not participate directly in creating collision domains or managing data traffic in the same way as hubs do.