CTA Fiber Optics & Physical Layer Technologies 2

Question 1

What is the maximum reach of 10GBASE-LR (10 Gigabit Ethernet over single-mode fiber) per IEEE 802.3ae?

Accepted Answer

10 kilometers

Answer

10GBASE-LR uses 1310 nm light over single-mode fiber and is specified for reaches up to 10 km per IEEE 802.3ae.

Question 2

In a Passive Optical Network (PON), what device splits the optical signal from the central office to multiple subscriber premises?

Accepted Answer

Optical splitter

Answer

A passive optical splitter divides the downstream optical signal from the OLT to multiple ONTs at subscriber locations without requiring electrical power.

Question 3

What is the maximum downstream bandwidth per PON port in XGS-PON (10G Symmetrical PON)?

Accepted Answer

10 Gbps

Answer

XGS-PON provides 10 Gbps symmetrical (downstream and upstream) bandwidth per PON port, per ITU-T G.9807.1.

Question 4

What causes optical back-reflection in a fiber link, and how is it typically mitigated?

Accepted Answer

Fresnel reflection at fiber end faces and connectors; mitigated using angled physical contact (APC) connectors or index-matching gel

Answer

Fresnel reflections occur at any glass-air interface (connectors, splices) and can disrupt laser sources; APC connectors reduce this by angling the end face to redirect reflections.

Question 5

In DSL technology, what does the term 'attenuation' refer to in the context of loop length?

Accepted Answer

The reduction in signal strength as the electrical signal travels over copper pairs, which increases with loop length

Answer

DSL performance degrades with loop length because the copper pair attenuates (weakens) the high-frequency signals, reducing achievable speed as distance from the DSLAM increases.

CTA - Certified Telecommunications Analyst Practice Test

CTA - Certified Telecommunications Analyst Practice Test

CTA Fiber Optics & Physical Layer Technologies 2