CCNA Network Infrastructure and Connectivity Practice Question
Which medium is the most common choice for a 10G uplink between wiring closets on different floors of the same building?
⚠ Common exam trap
Don't confuse the capabilities of multimode fiber with single-mode fiber for long-distance, high-speed connections.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Fiber optic cable
Fiber is commonly used for building uplinks because it supports higher bandwidth and longer distances than typical copper for this use case.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Rollover cable
Why it's wrong here
A rollover cable (Cisco rollover) has reversed pinouts between the two RJ-45 ends (pin 1 to pin 8, pin 2 to pin 7, etc.) and is used exclusively to connect a workstation's serial port to a network device's console port for out-of-band maintenance. It cannot carry Ethernet frames; it lacks the twisted-pair signaling and RJ-45 pin mapping defined by 10GBASE-T, and the console interface itself is asynchronous serial (typically 9600 baud). For a 10 Gbps switch uplink, you need a medium that supports high-frequency differential signaling over a proper Ethernet PHY, which a rollover cable does not.
When this WOULD be correct
If the exam question asked about connecting a terminal to a network device for configuration purposes, a rollover cable would be the correct choice. In such a scenario, the focus would be on management access rather than high-speed data transfer.
- ✓
Fiber optic cable
Why this is correct
Fiber-optic cable is the standard medium for 10G uplinks because it supports both 10GBASE-SR (multimode, 850 nm VCSELs, up to 300 m on OM3/OM4) and 10GBASE-LR (single-mode, 1310 nm, up to 10 km), providing reach and bandwidth far beyond copper twisted pair. It is immune to electromagnetic interference, has extremely low signal attenuation, and offers the full-duplex symmetric bandwidth required for switch uplinks. Enterprise switches therefore ship with SFP+ slots where fiber transceivers are the default choice for interconnecting access-layer switches to distribution or core switches.
- ✗
Coaxial cable
Why it's wrong here
Coaxial cable is not used as a modern enterprise 10G uplink medium because its applicable Ethernet variants (10BASE2, 10BASE5) are obsolete and cap at 10 Mbps, while 10GBASE-CX4, a short-range copper technique, actually uses twinaxial cable with dedicated SFF-8470 connections rather than standard coax like RG-6. Standard coaxial cable has a single center conductor and unidirectional shielding, making it unsuitable for the simultaneous bidirectional 10 Gbps signaling needed on an uplink, and its thickness and rigid terminating requirements complicate high-density patching in a wiring closet. Fiber or twisted-pair copper (Cat6a/7 for 10GBASE-T) are the practical alternatives.
When this WOULD be correct
If the exam question asked for the most common medium for a 10G uplink in a legacy network setup or a specific scenario where coaxial infrastructure is already in place and being upgraded, coaxial cable could be considered a viable option.
- ✗
Console cable
Why it's wrong here
A console cable provides access to the device's management plane via the console port, which is a low-speed asynchronous serial interface (typically RS-232 or USB-serial) used for initial configuration and troubleshooting. Unlike a switch uplink port, the console port has no MAC/PHY layer for Ethernet and cannot transmit data frames; it only interprets CLI commands as bytes over a serial link. Even if you physically forced an RJ-45 connector in, the signals would not conform to 10GBASE-T electrical specs, so the link would never come up at any speed.
When this WOULD be correct
If the exam question asked about connecting a network device directly to a computer for configuration purposes, a console cable would be the correct answer. This scenario would focus on device management rather than data uplinking.
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 200-301 exam frequently reuses these exact scenarios with slightly different constraints.
✓Fiber optic cableCorrect answer▾
Why this is correct
Fiber-optic cable is the standard medium for 10G uplinks because it supports both 10GBASE-SR (multimode, 850 nm VCSELs, up to 300 m on OM3/OM4) and 10GBASE-LR (single-mode, 1310 nm, up to 10 km), providing reach and bandwidth far beyond copper twisted pair. It is immune to electromagnetic interference, has extremely low signal attenuation, and offers the full-duplex symmetric bandwidth required for switch uplinks. Enterprise switches therefore ship with SFP+ slots where fiber transceivers are the default choice for interconnecting access-layer switches to distribution or core switches.
✗Rollover cableWrong answer — click to see why▾
Why this is wrong here
A rollover cable is a specialized Cisco console cable used for out-of-band management access to a device's console port, not for network data traffic. It cannot carry 10G Ethernet signals and is physically incompatible with Ethernet interfaces.
★ When this WOULD be the correct answer
If the exam question asked about connecting a terminal to a network device for configuration purposes, a rollover cable would be the correct choice. In such a scenario, the focus would be on management access rather than high-speed data transfer.
Why candidates choose this
Students may confuse rollover cables with other copper Ethernet cables (e.g., Cat6a) because both have RJ45 connectors, but rollover cables have a unique pinout (rolled) and are only used for console connections.
✗Coaxial cableWrong answer — click to see why▾
Why this is wrong here
Coaxial cable (e.g., RG-6) is primarily used for cable TV, broadband internet (DOCSIS), or legacy Ethernet (10BASE2/10BASE5), but it does not support 10G Ethernet speeds over the distances required between floors in a modern enterprise network. Fiber or twisted-pair copper (Cat6a/Cat7) are the standard 10G media.
★ When this WOULD be the correct answer
If the exam question asked for the most common medium for a 10G uplink in a legacy network setup or a specific scenario where coaxial infrastructure is already in place and being upgraded, coaxial cable could be considered a viable option.
Why candidates choose this
Coaxial cable is still used in some broadband and video applications, and its thick shielding might suggest it can handle high speeds, but it is not a standard for 10G Ethernet uplinks in structured cabling.
✗Console cableWrong answer — click to see why▾
Why this is wrong here
A console cable (typically a rollover or USB-to-serial cable) is used for initial device configuration and management access, not for carrying network traffic. It cannot support 10G data rates and is not designed for switch-to-switch uplinks.
★ When this WOULD be the correct answer
If the exam question asked about connecting a network device directly to a computer for configuration purposes, a console cable would be the correct answer. This scenario would focus on device management rather than data uplinking.
Why candidates choose this
The term 'console cable' might be confused with 'crossover cable' or other Ethernet cables, but console cables are specifically for management and have different connectors and pinouts.
Analysis generated from the official 200-301blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Quick reference
OSI Model Reference
| Layer | Name | PDU | Key Protocols / Devices |
|---|---|---|---|
| 7 | Application | Data | HTTP, HTTPS, DNS, SMTP, FTP, SSH |
| 6 | Presentation | Data | TLS / SSL, JPEG, ASCII encoding |
| 5 | Session | Data | NetBIOS, RPC, SIP |
| 4 | Transport | Segment / Datagram | TCP, UDP |
| 3 | Network | Packet | IP, ICMP, OSPF — Routers |
| 2 | Data Link | Frame | Ethernet, Wi-Fi, PPP — Switches, Bridges |
| 1 | Physical | Bits | Cables, NICs, Hubs, Repeaters |
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Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This 200-301 practice question is part of Courseiva's free Cisco certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 200-301 exam.