Which instrument is described as a network multimeter used for troubleshooting and testing the physical and data link layers?

• A. Digital multimeter
• B. Fluke LinkRunner
• C. Spectrum analyzer
• D. Oscilloscope

Answer: (B)

Tools that combine cable verification with basic Ethernet checks focus on validating the physical wiring and the data link status. The Fluke LinkRunner fits this need precisely: it’s a handheld network tester designed as a network multimeter, capable of cable tests (wire map, length, faults), checking PoE presence, and quickly validating Ethernet connectivity and port reachability on a switch. This lets you confirm both that the cabling is sound and that the data link layer between devices is functioning. A digital multimeter measures electrical quantities like voltage and resistance but isn’t used for network path or link testing. A spectrum analyzer examines RF frequency spectra, not Ethernet cables or layer-2 links. An oscilloscope shows voltage waveforms and timing, which is broader electronics work and not tailored to network layer diagnostics.