Cable Issues

Question 1

Fiber Mismatching

Answer 1

Fiber Mismatching → A problem caused by using different types of fiber (such as single-mode with multimode) or mixing connectors, which leads to signal loss, light dispersion, and poor performance.

Question 2

Cable Category Summary

Answer 2

Cable Category Summary →
CAT5: 100 MHz, 100 Mbps.

CAT5e: 100 MHz, 1 Gbps.

CAT6: 250 MHz, 1 Gbps.

CAT6A: 500 MHz, 10 Gbps.

CAT7: 600 MHz, 10 Gbps.

CAT8: 2000 MHz, 25–40 Gbps.

Question 3

UTP Cable

Answer 3

Unshielded Twisted Pair (UTP) Cable → Copper cabling with twisted pairs but no shielding; cheaper, flexible, and used in most Ethernet networks.

Question 4

STP Cable

Answer 4

Shielded Twisted Pair (STP) Cable → Copper cabling with shielding around pairs or the entire bundle to reduce interference in high-noise environments.

Question 5

XT

Answer 5

Crosstalk (XT) → Interference caused when signals on one twisted pair bleed onto another pair in the same cable.

Question 6

NEXT

Answer 6

Near-End Crosstalk (NEXT) → Measurement of crosstalk interference detected at the same end where the signal is transmitted.

Question 7

FEXT

Answer 7

Far-End Crosstalk (FEXT) → Measurement of crosstalk interference detected at the opposite end of the cable from where the signal originated.

Question 8

AXT

Answer 8

Alien Crosstalk (AXT) → Interference caused by signals leaking from adjacent cables rather than pairs within the same cable.

Question 9

ACR

Answer 9

Attenuation to Crosstalk Ratio (ACR) → A measurement comparing received signal strength to crosstalk levels; higher ACR means a cleaner signal and better performance.

Question 10

SNR

Answer 10

Signal-to-Noise Ratio (SNR) → A measurement comparing signal strength to background noise; used with Attenuation to Crosstalk Ratio (ACR) to assess link quality.

Question 11

EMI

Answer 11

Electromagnetic Interference (EMI) → Interference from electrical devices or cabling; twisted pairs help cancel EMI through opposing electromagnetic fields.

Question 12

Attenuation

Answer 12

Attenuation → Loss of signal strength as it travels over distance, occurring in both copper and fiber connections.

Question 13

TIA 568A Cable

Answer 13

Wire order:
Green/White
Green
Orange/White
Blue
Blue/White
Orange
Brown/White
Brown.

Question 14

TIA 568B Cable

Answer 14

Wire order:
Orange/White
Orange
Green/White
Blue
Blue/White
Green
Brown/White
Brown.