You are cabling a Windows NT office network located adjacent to a building power plant (a high-EMI environment). To minimize susceptibility to electromagnetic interference and maximize signal integrity, which cabling type is the best choice?

Introduction / Context:
Selecting media for LAN cabling near heavy electrical equipment requires attention to electromagnetic interference (EMI). Power plants, elevators, and large motors generate strong fields that can induce noise on copper conductors, degrading throughput and causing errors. The goal is to choose a medium intrinsically immune to EMI for a reliable Windows NT network deployment.

Given Data / Assumptions:

• The office is beside a building power plant (severe EMI).
• Standard LAN distances and speeds are assumed.
• We prefer a robust, future-proof, standards-based medium.

Concept / Approach:
Optical fiber carries signals as light, not electrical current, and is therefore immune to electromagnetic interference and radio-frequency interference. It also provides excellent security (difficult to tap) and supports long runs and high bandwidth. Unshielded twisted pair (UTP) is economical but most vulnerable to strong EMI. Shielded twisted pair (STP) provides better common-mode rejection, yet can still be affected and requires meticulous grounding to be effective. PSTN is not a LAN cabling medium. “TI” is not a recognized cable type here (likely a distractor). Therefore, fiber-optic cabling is the best choice in this high-EMI scenario.

Step-by-Step Solution:

Verification / Alternative check:
Industry design guides recommend fiber for plant floors and high-EMI areas. Many enterprises use fiber risers and backbones specifically to avoid electrical coupling issues present in copper solutions.

Why Other Options Are Wrong:

• UTP: highly susceptible to strong EMI in proximity to power equipment.
• STP: better than UTP but still copper; needs perfect bonding/grounding and can still pick up interference.
• PSTN: a public telephone network service, not LAN cabling.
• TI: not a standard LAN cable type; distractor.

Common Pitfalls:
Assuming thicker copper or shielding always solves EMI; improperly grounded STP can behave worse than UTP. Overlooking fiber's advantages in safety isolation between electrical systems.

Final Answer:
Fiber-optic.