Exam N10-008 topic 1 question 56 discussion

A is correct. A mismatch will usually generate excessive CRC errors. Mismatch = ERROR

- The different duplex settings on both ends of a connection can cause a mismatch in the flow control (sending data at different speed), leading data collisions. These collisions can result in corrupted data and increase the number of CRC errors.

From wikipedia on the duplex mismatch page: "This results in the full-duplex side receiving an incomplete frame with CRC error or a runt frame" So, it is a question to think about

According to the official CompTIA Network+ 008 Student Guide (Lesson 12, page 291): "A runt is a frame that is smaller than the minimum size (64 bytes for Ethernet). A runt frame is usually caused by a collision. In a switched environment, collisions should only be experienced on an interface connected to a legacy hub device and there is a duplex mismatch in the interface configuration (or possibly on a misconfigured link to a virtualization platform)." It looks like Runt Frame Errors are caused by Collisions, and collisions are caused by Duplex Mismatch. Option B sounds like a good answer to me.

increased crcs errors

For monitoring and troubleshooting purposes, interface diagnostics might be accessible. This diagnostic information might include various error conditions, such as late collisions or cyclic redundancy check (CRC) errors, which might indicate a duplex mismatch. --Anthony Sequeira, N10-008 Cert Guide