Digital Communications Multiple Choice Questions on “Abstraction and layering”.
1. Top layer is
A. Physical media
B. Application
C. Design
D. None of the mentioned
Answer: B
Clarification: Top layer is application where as bottom layer is physical media.
2. Entities also does
A. Error correction
B. A/D
C. D/A
D. All of the mentioned
Answer: D
Clarification: Entities also does A/D, D/A, encryption and error correction.
3. In channel, delay is
A. Fixed
B. Variable
C. Fixed & Variable
D. None of the mentioned
Answer: C
Clarification: In channel, delay can be either fixed or variable.
4. Channel can provide connectivity to
A. Point to point
B. 1 to many
C. Many to many
D. All of the mentioned
Answer: D
Clarification: Channel can provide connectivity between point to point, 1 to many and also many to many.
5. Embedding is a form of
A. Abstraction
B. Layering
C. Entity sharing
D. None of the mentioned
Answer: B
Clarification: Embedding is a form of layering.
6. Transmission media is
A. Acoustic
B. Guided
C. Optical
D. All of the mentioned
Answer: D
Clarification: Transmission media can be acoustic, electronic or optical form.
7. In transmission media, the symbol type is generally
A. Analog
B. Digital
C. Analog & Digital
D. None of the mentioned
Answer: A
Clarification: In transmission media, the symbol type is generally analog signals.
8. Noise is _____ in nature.
A. Random
B. Systematic
C. Random or Systematic
D. None of the mentioned
Answer: C
Clarification: Noise can be random or systematic.
9. The radiation loss increases as
A. Frequency increases
B. Frequency decreases
C. Does not depend on frequency
D. None of the mentioned
Answer: A
Clarification: The radiation loss increases as frequency increases.
10. Attenuation is a function of
A. Channel length
B. Transmission media
C. Signal frequencies
D. All of the mentioned
Answer: D
Clarification: Attenuation is a function of channel length, transmission media and signal frequencies.