Examkin

Question

Difficulty: HardNetwork Cable Types and Connectors

A network administrator is designing a structured cabling deployment for a commercial facility with two specific installation requirements:

1. A 250-meter interconnect between two distribution closets that passes near high-voltage electrical conduits.
2. Horizontal cable runs routed above a drop ceiling in an environmental air plenum space.

Which TWO of the following cabling types or jacket ratings must the administrator specify to meet these deployment requirements correctly? (Select TWO.)

  1. Single-mode fiber optic cabling with LC connectors for the inter-closet backbone linkAnswer
  2. Plenum-rated CMP twisted-pair cabling for the horizontal ceiling dropsAnswer
  3. C
    Unshielded Category 6a PVC-jacketed cabling for the inter-closet backbone link
  4. D
    Riser-rated CMR twisted-pair cabling for the horizontal ceiling drops

Answer

The administrator must specify single-mode fiber optic cabling with LC connectors for the 250-meter backbone link and plenum-rated (CMP) cabling for the environmental ceiling drops.
Single-mode fiber optic cable provides complete immunity to high-voltage electromagnetic interference (EMI) and supports transmission distances far greater than the 100-meter maximum of twisted-pair copper cable. Additionally, plenum-rated (CMP) cabling is coated with flame-retardant materials that emit minimal smoke and non-toxic fumes in the event of a fire, making it mandatory for environmental air handling spaces above drop ceilings.

Step-by-Step Solution

1
Analyze the backbone link requirements (250 meters, high EMI risk).
Twisted-pair copper cables (such as Cat 5e, Cat 6, or Cat 6a) are limited to a maximum length of 100 meters100\text{ meters} and are vulnerable to EMI. Single-mode fiber optic cable supports distances up to 10 km10\text{ km} or more and is completely immune to EMI.
The distance exceeds copper bandwidth/distance constraints and requires optical signal transmission.
2
Analyze the environmental ceiling space requirements.
Drop ceiling areas used for air circulation are classified as plenum spaces. Fire safety regulations require CMP (plenum-rated) jackets, which are flame-retardant and produce minimal smoke.
Standard PVC or CMR (riser) jackets produce toxic fumes and heavy smoke during a fire.

Key Concept

Network Media Selection, Cable Length Constraints, EMI Immunity, and Fire-Safety Jacket Ratings
Rate this question

Topics

Network Cable Types and Connectors

More questions from this topic