Cabling a 10Base2 Ethernet: donated adapters are 10Base2 (thin Ethernet) and some ARCnet coax cards. Which coaxial cable type should be used to wire a reliable 10Base2 Ethernet segment?

Introduction / Context:
10Base2 (thin Ethernet) specifies a bus topology using 50-ohm coaxial cable. Using the correct cable type and connectors is essential for reliability. ARCnet used different media options historically, often 93-ohm coax, so mixing standards or using TV coax leads to errors and CRC failures.

Given Data / Assumptions:

• Goal: operate 10Base2 Ethernet, not ARCnet.
• Proper cable impedance for 10Base2: 50 ohms.
• Environment: short school network with donated cards and cables.

Concept / Approach:

10Base2 requires RG-58 A/U (50-ohm) coax with BNC connectors, T-pieces at each NIC, and 50-ohm terminators at both segment ends. Using 75-ohm TV coax such as RG-59 causes signal reflections and severe errors. RJ-11 and RJ-45 describe modular connectors, not coax cable, and are irrelevant for 10Base2 bus wiring.

Step-by-Step Solution:

Verification / Alternative check:

Signal integrity checks and collision/error counters improve markedly when 50-ohm RG-58 A/U replaces 75-ohm cable, confirming specification compliance.

Why Other Options Are Wrong:

RG-59 A/U: 75-ohm TV coax; wrong impedance.

RJ-11/RJ-45: Connector types for twisted pair; not coax and not 10Base2 bus medium.

None of the above: Incorrect because RG-58 A/U is correct.

Common Pitfalls:

Using RG-59 from CCTV/TV spares; forgetting both-ends termination; placing T-connectors incorrectly.

Final Answer:

RG-58 AU