N10-009 Networking Concepts Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  A hub operates at Layer 2, while a switch operates at Layer 1.

  Why it's wrong here

  This statement incorrectly assigns the OSI model layers to the devices. A hub is a Layer 1 (Physical Layer) device, meaning it only deals with the physical transmission and reception of raw bit streams without any understanding of data frames or addresses. Conversely, a switch operates at Layer 2 (Data Link Layer), where it can interpret MAC addresses, build a MAC address table, and make intelligent forwarding decisions based on these addresses, providing more advanced network functionality.

  When this WOULD be correct

  This option would be correct if the question asked: 'Which statement incorrectly describes the difference between a hub and a switch?' or if the question was about a device that operates at Layer 2 (like a switch) versus a device that operates at Layer 1 (like a hub), but with the layers swapped.

• ✓

  A hub sends frames out all ports except the incoming port; a switch sends frames only to the port with the matching MAC address.

  Why this is correct

  A hub is a Layer 1 device that simply regenerates electrical signals, broadcasting incoming data frames to all connected ports except the one from which the frame originated, without any intelligence. In contrast, a switch is a Layer 2 device that intelligently learns the MAC addresses of connected devices and stores them in its MAC address table. When a switch receives a frame, it examines the destination MAC address and forwards the frame only to the specific port associated with that MAC address, significantly reducing unnecessary network traffic and improving efficiency.

• ✗

  A hub uses MAC addresses to make forwarding decisions, while a switch uses IP addresses.

  Why it's wrong here

  This statement is incorrect because hubs are Layer 1 devices and operate solely on electrical signals, lacking any intelligence to interpret MAC addresses for forwarding decisions; they simply broadcast all received data. Conversely, a standard Ethernet switch operates at Layer 2 (Data Link Layer) and makes its forwarding decisions based on destination MAC addresses, which it learns and stores in its MAC address table. While Layer 3 switches exist, a typical Layer 2 switch does not use IP addresses for basic frame forwarding.

  When this WOULD be correct

  This option would be correct in a question comparing a router and a switch, where the router uses IP addresses (Layer 3) and the switch uses MAC addresses (Layer 2).

• ✗

  A hub creates a separate collision domain for each port, while a switch creates a single collision domain.

  Why it's wrong here

  This statement is factually reversed regarding collision domains. A hub operates as a shared medium, meaning all devices connected to it are part of a single, large collision domain. Any transmission from one device is seen by all others, and simultaneous transmissions result in collisions, degrading performance. In contrast, a switch creates a separate collision domain for each of its ports, effectively isolating traffic and preventing collisions between devices connected to different ports, thereby enhancing network throughput.

  When this WOULD be correct

  If the question asked 'Which statement correctly describes a key difference between a hub and a switch regarding collision domains?' and the options were reversed (e.g., 'A hub creates a single collision domain, a switch creates separate collision domains'), then this option would be correct.

Option-by-option analysis

Why each answer is right or wrong

Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The N10-009 exam frequently reuses these exact scenarios with slightly different constraints.

Analysis generated from the official N10-009blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”