Nokia 4A0-265 Nokia Optical Diagnostics and Troubleshooting Exam Practice Test

The command show wavekey wtmonitor 1/6/LINE summary displays a list of all channels detected against the selected interface (in and out); it shows if a Wave Keys pair is expected, if a Wave Keys pair is received, and if the received Wave Keys pair is unexpected. A Wave Keys pair is a pair of unique identifiers that are transmitted along with an optical channel to provide channel identification and monitoring functions. The command can be used to verify the presence and correctness of the Wave Keys pairs on an interface and to detect any mismatch or misconfiguration. The other options are incorrect because they either describe a different command or provide incorrect information. References: Nokia Optical Diagnostics and Troubleshooting Course, OAM and Diagnostics Guide

The exhibit shows a diagram of a network with two nodes, Node A and Node B, connected by a fiber span. The diagram also shows the power readings at different points of the span. The calculated span loss from Node A to Node B is the difference between the output power at Node A and the input power at Node B. According to the diagram, the output power at Node A is +3.5 dBm and the input power at Node B is -4.5 dBm. Therefore, the span loss from Node A to Node B is 3.5 - (-4.5) = 8.0 dB.

The command show xc 1 displays a list of cross-connections, including A-end, Z-end, frequency, ID number, OCH trail name, and administrative/operational states. A cross-connection is a logical connection between two ports on an optical network element that allows the transmission of an optical signal from one port to another. The command can be used to view the configuration and status of the cross-connections on a node or a network. The other options are incorrect because they either describe a different command or provide incorrect information. References: Nokia Optical Diagnostics and Troubleshooting Course, OAM and Diagnostics Guide

The exhibit shows a diagram of an OT module with a client port and a DWDM port. The client port is looped back to itself with an OEO (Optical-Electrical-Optical) device. This means that the signal received by the client port is converted to an electrical signal, then back to an optical signal, and then transmitted back to the same port. This type of loopback is called a client portterminal loopback. It is used to test the functionality of the client port without involving the DWDM port or any other network element4. A client port facility loopback would involve looping back the signal from the DWDM port to the client port. A line port facility loopback would involve looping back the signal from another OT module or network element to the DWDM port. A line port terminal loopback would involve looping back the signal from the DWDM port to itself5. References : Nokia Optical Diagnostics and Troubleshooting Course | Nokia, Loopback - Wikipedia

When troubleshooting possible generic fiber cuts, the recommended first step is to review alarms at nodes where power loss occurs. This can help identify the location and extent of the fiber cut and the affected services. The next recommended step is to perform network power traces to attempt to determine the point of power loss. Network power traces are graphical representations of the optical power levels along a span or a path. They can be used to compare the measured power levels with the expected power levels and to pinpoint any significant deviations or drops that indicate a fiber cut. The other options are incorrect because they either do not help locate the fiber cut or are not as effective as network power traces. References: Nokia Optical Diagnostics and Troubleshooting Course, OAM and Diagnostics Guide

Performance Measurement (PM) is a feature that collects and reports various statistics related to the performance of an optical network element. PM data can be retrieved at different levels, such as Optical Channel (OCh), Optical Channel Data Unit (ODU), Optical Channel Transport Unit (OTU), and Ethernet. An Optical Transponder (OT) is a device that converts an electrical signal into an optical signal and vice versa. An OT has two interfaces: a client interface and a line interface. The client interface connects to the service provider network, while the line interface connects to the optical transport network. At the OT line interface, PM data can be retrieved for the OCh, ODU, OTU, and Digital Wrapper (DW) levels. The DW is a layer that encapsulates the client signal and provides overhead information for monitoring and management purposes. Ethernet collision counters are not typically retrieved at the OT line interface, as they are related to the Ethernet level, which is usually monitored at the client interface. References: Nokia Optical Diagnostics and Troubleshooting Course, Nokia 1830 PSS-32 and PSS-16 Photonic Service Switch Release 8.0 Performance Monitoring Reference Guide

The command config powermgmt egress 1/2 adjust status is used to enable or disable the power adjustment feature on the specified egress amplifier. The power adjustment feature is a function that automatically adjusts the output power of an amplifier to compensate for changes in the input power or the number of channels. This feature can be enabled or disabled on both ingress and egress amplifiers, depending on the network configuration and requirements1. Therefore, the statement C is true. References : Nokia Optical Diagnostics and Troubleshooting Course | Nokia

The calculated span loss from Node A to Node B is 10.0 dB. Span loss is the difference between the optical power transmitted and received at two points in a network. It can be calculated by subtracting the received power from the transmitted power. In the exhibit, the transmitted power from Node A to Node B is +7.5 dBm, and the received power at Node B from Node A is -2.5 dBm. Therefore, the span loss is +7.5 dBm - (-2.5 dBm) = 10.0 dB. The other options are incorrect because they do not match the calculation. References: Nokia Optical Diagnostics and Troubleshooting Course, Pluggable Optical Modules: Transceivers for the Cisco ONS Family Data Sheet

1-Day PMs are one of the types of PM data that can be retrieved from an optical network element. 1-Day PMs show measurements collected over the preceding 24 hours, with each hour being a bin. Up to 8 bins are available for data storing, which means that only the most recent 8 hours of data can be accessed. The other types of PM data are 15-Minute PMs, which show measurements collected over the preceding 15 minutes, with each minute being a bin, and Total PMs, which show measurements collected since the last reset of the PM counters. References: Nokia Optical Diagnostics and Troubleshooting Course, Nokia 1830 PSS-32 and PSS-16 Photonic Service Switch Release 8.0 Performance Monitoring Reference Guide

The command that should be used to configure the 10GbE client interface 1/7/C1 with a GFP-F encapsulation mode is config interface 1/7/C1 encmode 10client gfp-f. This command will set the encapsulation mode of the interface to GFP-F, which is a frame-mapped generic framing procedure that encapsulates Ethernet frames with a GFP header. The command also specifies that the interface is a 10GbE client interface, which means that it supports 10 Gigabit Ethernet LAN signals. The other commands are incorrect because they either have invalid syntax or use incorrect parameters for the interface or the encapsulation mode. References: Nokia Optical Diagnostics and Troubleshooting Course, OAM and Diagnostics Guide

The payload type setting is an attribute that is recorded within the client payload and can be set automatically or manually. The payload type setting indicates the type of client signal that is carried by the OTN frame, such as Ethernet, Fibre Channel, or SDH/SONET. The payload type setting can be used for service identification and performance monitoring purposes. The payload type setting can be set automatically by the ML-Series card, which can detect the client signal type and encode it in the payload header. Alternatively, the payload type setting can be set manually by the user using the command config interface encmode payloadtype , where  is the client interface name,  is the encapsulation mode, such as GFP-F or BMP, and  is the client signal type, such as 10GE LAN or FC-1200. The other options are incorrect because they either state that the payload type setting is recorded within the OTN overhead, which is not true, or that it must be entered manually, which is not necessary. References: Nokia Optical Diagnostics and Troubleshooting Course, OAM and Diagnostics Guide

The available output optical power range is the difference between the maximum gain and the minimum gain range of the ingress amplifier. According to the EPT Power Management Report, the maximum gain is 25.7 dB and the minimum gain range is 14 dB. Therefore, the available output optical power range is 25.7 - 14 = 11.7 dB. To convert this to a logarithmic scale, we use the formula 10^(x/10), where x is the value in dB. Therefore, the available output optical power range in logarithmic scale is 10^(11.7/10) - 10^(14/10) = 14.68 - 25.12 = -0.6 to 1.72dB. References : Nokia Optical Diagnostics and Troubleshooting Course | Nokia, EPT Power Management Report | Nokia