VDV Network Infrastructure 5

Question 1

What is the maximum allowable pair untwist at a termination point per TIA-568 for Cat6 cable?

Accepted Answer

13 mm (0.5 inch)

Answer

TIA-568-C.2 limits pair untwist at terminations to 13 mm (0.5 inch) for Cat6 to maintain crosstalk performance at the connection point.

Question 2

Which test parameter measures the signal leakage from one pair to an adjacent pair at the same end of the cable being tested?

Accepted Answer

NEXT (Near-End Crosstalk)

Answer

NEXT measures the unwanted signal coupling from a transmitting pair to an adjacent pair measured at the same end of the cable, which is the most critical crosstalk parameter.

Question 3

In a structured cabling design, what is the maximum recommended horizontal cable run length including the patch cords?

Accepted Answer

90 meters for the permanent link, with total channel up to 100 meters

Answer

TIA-568 specifies a 90-meter permanent link for horizontal cabling, with up to 10 meters allocated for patch cords and equipment cords for a 100-meter total channel.

Question 4

What is the primary advantage of using shielded twisted pair (STP) cable versus unshielded twisted pair (UTP) in a VDV installation?

Accepted Answer

STP provides improved immunity to electromagnetic interference (EMI)

Answer

The metallic shield in STP cable reduces susceptibility to external EMI sources, making it preferred in environments with heavy electrical equipment or interference.

Question 5

A network closet has a switch with a faulty uplink to the MDF. The technician needs to verify the fiber patch cable is good. Which test should be performed first?

Accepted Answer

Visual inspection and optical power meter test

Answer

Visual inspection for physical damage followed by an optical power meter test is the fastest and most practical first step to verify patch cable integrity.

(VDV) Voice Data Video Technician Certified Practice Test

(VDV) Voice Data Video Technician Certified Practice Test

VDV Network Infrastructure 5