Which device types are responsible for isolating traffic within an Ethernet network?

The correct choice highlights the role of bridges, switches, and routers in managing and isolating traffic within an Ethernet network. These devices are essential for segmenting network traffic, enhancing performance, and improving security.

Bridges operate at the data link layer, managing traffic between different network segments and reducing collisions by dividing a larger network into smaller, more efficient segments. This operation enables better traffic management, as broadcast domains can be isolated.

Switches, which also function at the data link layer, further refine this concept by creating a separate collision domain for each connected device, allowing multiple simultaneous conversations on the network. This capability significantly improves network throughput and reduces the chances of packet collisions.

Routers operate at a higher layer (network layer) and facilitate traffic between different networks, thus providing both isolation and connectivity. They can filter traffic based on IP addresses and manage routing decisions, making them crucial for directing packets efficiently and securely across diverse network environments.

Other options such as hubs and repeaters do not isolate traffic; they transmit the same signal to all connected devices, leading to greater chances of collisions without managing broadcast domains. Modems, while necessary for connecting to external networks, also do not provide isolation within an Ethernet network. Network interface cards serve as the hardware interface for