Which switching method reduces latency but can forward bad frames?

• A. Store and Forward
• B. Fragment-Free
• C. Cut-through
• D. Forward Filter Decision

Answer: (C)

In Ethernet switching, the way a switch handles a frame changes both how fast it can forward and how much error checking it does. The method that minimizes delay is cut-through: the switch starts forwarding as soon as the destination MAC address (and part of the header) is read, without waiting for the entire frame or its CRC. That cuts latency dramatically because forwarding can begin while the rest of the frame is still arriving. But the tradeoff is clear: the CRC isn’t checked before forwarding, so a frame with errors can be sent onward. Fragment-free and store-and-forward delay more to verify the frame (the first 64 bytes to avoid runt frames, or the whole frame with CRC respectively), increasing latency but providing more reliable error handling. The option listed as Forward Filter Decision isn’t a standard switching method.