220-1101 Question 134
Single answerSwitchA technician replaces an old unmanaged 100 Mbps switch in a small office with a new Gigabit switch. After the upgrade, users report that large file transfers between PCs are much faster, but internet speed tests are unchanged. The office internet service is 200 Mbps download, and the router connected to the switch has a 1 Gbps LAN port. Which of the following BEST explains the users' results?
- A
The switch improves local network throughput between devices on the LAN, but it does not increase the speed provided by the ISP
- B
A Gigabit switch automatically boosts the WAN connection speed by caching internet traffic locally
- C
The new switch forces all devices to use half-duplex, which helps file transfers but not internet traffic
- D
The router's 1 Gbps LAN port limits internet traffic to 100 Mbps regardless of the ISP plan
Show answer and explanation
Correct answer: A
Explanation
The best answer is that the switch upgrade improved LAN performance, not WAN bandwidth. In real-world troubleshooting, this distinction is essential: switches forward Ethernet frames inside the local network, so upgrading from Fast Ethernet (100 Mbps) to Gigabit Ethernet (1000 Mbps) often improves local file copies, access to shared storage, and other internal traffic. Internet performance, however, depends on the ISP subscription, modem, router, and external network path. This aligns with standard networking best practices and vendor documentation from major networking manufacturers, which distinguish LAN switching capacity from WAN/internet service speed. On the A+ Core 1 exam, candidates should recognize that a switch can remove a local bottleneck without changing the office's purchased internet bandwidth.
- A. Correct.
Correct. A switch primarily affects traffic within the local area network by forwarding frames between connected devices at the speed supported by the switch ports and the NICs of the endpoints. Replacing a 100 Mbps switch with a Gigabit switch can significantly improve PC-to-PC file transfers, network backups, and access to local servers or NAS devices. However, internet speed is still constrained by the ISP service level, modem, router, and WAN path, so a faster switch alone does not increase the subscribed internet bandwidth.
- B. Incorrect.
Incorrect. Standard Ethernet switches do not increase WAN bandwidth by caching internet traffic in a way that raises speed test results. While some network devices may buffer packets temporarily, that is not the same as boosting ISP-provided throughput. This option reflects a common misconception that any faster network hardware will automatically make internet access faster.
- C. Incorrect.
Incorrect. Gigabit Ethernet normally operates in full-duplex, not half-duplex, when properly negotiated. Forcing half-duplex would typically create performance problems such as collisions and reduced throughput rather than improved file transfers. This option is based on a misunderstanding of duplex settings and switch operation.
- D. Incorrect.
Incorrect. A router LAN port rated at 1 Gbps does not cap internet traffic at 100 Mbps. In this scenario, the ISP connection is 200 Mbps, which is well below the router's 1 Gbps LAN capability. If anything, a 1 Gbps LAN port provides enough capacity for the 200 Mbps internet service on the internal side. The limitation on internet speed would come from the ISP plan or WAN-side constraints, not from a Gigabit LAN port.