Which of the following is the last field in an Ethernet frame?

In an Ethernet frame, the last field is the Frame Check Sequence (FCS). The FCS is a crucial part of error detection in networking. It helps ensure the integrity of the data being transmitted. When a device receives an Ethernet frame, it calculates the FCS on the received data and compares it with the FCS value included in the frame. If the two values match, it indicates that the frame was received correctly without any errors during transmission.

The FCS field is typically 4 bytes long and is specifically designed for detecting errors caused by noise and interference that may occur during the transmission over the physical medium. By placing the FCS field at the end of the frame, it allows for the entire data payload to be checked for integrity after it has been received.

Understanding the structure of an Ethernet frame, including the position and purpose of the FCS, is essential in networking, as it plays a vital role in ensuring reliable data communication across networks.