What best describes the function of autonegotiation in Fast Ethernet?

Autonegotiation in Fast Ethernet is a crucial function that allows devices on a network to automatically exchange information about their capabilities and select the best possible settings for communication. This process is designed to ensure that both devices can operate at the highest speed and duplex mode they support, which optimizes network performance.

When two devices that support autonegotiation connect, they communicate their capabilities, such as the maximum speed they can achieve (e.g., 10 Mbps, 100 Mbps) and whether they support full-duplex or half-duplex operation. The autonegotiation process then selects the highest common set of parameters that both devices can support, thereby maximizing throughput and minimizing potential conflicts that could arise if they were operating at different speeds or modes.

This function is essential in maintaining efficient data transmission and ensuring compatibility between different network devices, leading to a more robust and performant network environment.