DCN_Unit2

A digital signal with a bit rate of 2 Mbps is transmitted over a medium with a propagation speed of 2 × 10⁸ m/s. What is the bit length?

• 1 m

• 10 m

• 100 m

• 0.1 m

During a video call, some packets arrive late and out of order. What issue is the user experiencing?

• Latency

• Jitter

• Attenuation

• Bandwidth mismatch

How would poor frame synchronization affect a synchronous TDM system?

• Bit rate would increase

• Output becomes continuous

• Bandwidth will be over-utilized

• Data from one source may be received by another

Why might a virtual-circuit network experience variable packet delay even if all packets take the same path?

• Resources are allocated dynamically

• Packets are encoded differently

• Transmission uses different channels

• Addressing errors

What happens if bandwidth-delay product is large in a network link?

• Less data can be in transit

• More bits can be in transit

• Jitter is zero

• Signal-to-noise ratio improves

Which of the following situations would require modulation of a digital signal before transmission?

• When the channel is low-pass

• When the bit rate is very low

• When the medium only supports analog bandpass signals

• When using a fiber-optic link

Which transmission impairment would most likely occur if different frequency components of a signal arrive at different times?

• Distortion

• Attenuation

• Noise

• Jitter

How would using 8 signal levels in a noiseless channel with 3 kHz bandwidth impact the data rate? (Nyquist's formula)

• It would provide a data rate of 18 kbps

• It would provide a data rate of 6 kbps

• It would create interference

• It would decrease bandwidth

If you’re transmitting a 4 MB file over a channel with 1 Mbps bandwidth, ignoring delay and losses, what is the ideal transmission time?

• 8 seconds

• 4 seconds

• 32 seconds

• 31. 16 seconds

Which multiplexing method would be most appropriate for combining multiple optical signals?

• FDM

• TDM

• CDM

• WDM