Free Nokia Advanced Optical Network Design Exam 4A0-255 Exam Practice Test

Which of the following statements about the management plane data Communications Network (DCN) is correct?

• The management plane DCN uses in-band communication.
• The management plane DCN can be connected to each NEs via OSS/OBS interface.
• The management plane DCN can be connected to each NEs directly.
• The management plane DCN enables direct communication between the NEs.

Which of the following statements about GMPLS features is FALSE?

• GMPLS is able to manage the optical network through the DCN.
• GMPLS is able to control OTN networks.
• GMPLS is able to compute the routing of the optical channels.
• GMPLS is able to automatically provision the optical channels.

Which of the following best describes Four Wave Mixing (FWM)?

• FWM is a linear impairment that produces crosstalk four adjacent wavelengths are used.
• FWM is a non-linear impairment that produces crosstalk at the sum and difference of two wavelengths.
• FWM is a non-linear impairment resulting from varying velocities at different frequencies.
• FWM is a linear impairment resulting from pulses broadening over ultra-long distances

Which of the following about the Optical channel Transport Unit (OUT0 in ONT network is correct?

• OUT refer to the section between two multiplexers passing through one or more amplifiers.
• OUT refers to the section between two amplifiers.
• OUT enables the multiplexing of OCH connections.
• OUT enables FEC processing.

Where is guardband mandatory for EMF?

• Between 10G and 40G channels
• Between 10G and 100G channels
• Between 10G and 200G channels
• Between 40G and 100G channels

Suppose that for a given number of buffer credits and for an given average FC frame size, the maximum FC link length is 50 km.If the average FC frame size is doubled, which of the following is correct?

• The throughput is halved.
• Throughput is doubled.
• The Throughput is the same,.
• The buffer credits need to be adjusted to achieve the maximum throughput.

Suppose there is a 40 Gbit/s signal which has a symbol rate of Gbaud/s. Which modulation format is being used?

• QPSK
• BPSK
• 4QAM
• DP-QPSK

Which of the following statements about an alien wavelength at 10G is correct?

• It is an optical signal generated by FWM impairment.
• It has similar optical performance across multiple vendors equipment at 10G.
• It can be measured by a VAC card.
• It does not support Wavelength tracker.

Which of the following statements about the Decision (HDEFC) decoding and soft decision FEC (SDFEC) decoding is FALSE?

• HDFEC injects less latency into the decoding process than SDFEC.
• HDFEC provides a higher coding gain than SDEFC
• HDFEC uses fewer thresholds than SDEFC.
• HDFEC discards bits earlier in the decoding process than SDEFC.

Consider two EDFA amplifiers in cascade. Each EDFA has an average input signal power of 10 mW and an average noise power of 1 mW. What is the OSNR of the system at the receiver.

• 20 dB
• 10 dB
• 7 dB
• 5 bB