- (Topic 3)
A technician just validated a theory that resolved a network outage. The technician then verified that all users could access resources. Which of the following is the next step the technician should take in the network troubleshooting methodology?
Correct Answer:
C
The network troubleshooting methodology is a systematic process of identifying and resolving network problems. It consists of eight steps:
* 1. Identify the problem.
* 2. Establish a theory of probable cause.
* 3. Test the theory to determine the cause.
* 4. Establish a plan of action to resolve the problem and identify potential effects.
* 5. Implement the solution or escalate as necessary.
* 6. Verify full system functionality and, if applicable, implement preventive measures.
* 7. Document findings, actions, and outcomes.
* 8. Write the lessons learned.
The last step, writing the lessons learned, is important for improving the network troubleshooting skills and knowledge. It involves reviewing the entire troubleshooting process, analyzing the root cause of the problem, evaluating the effectiveness of the solution, and identifying any best practices, tips, or tools that can be used for future reference. Writing the lessons learned can also help to update the network documentation, policies, and procedures, and share the experience and feedback with other network professionals
- (Topic 1)
A network administrator discovers that users in an adjacent building are connecting to the company’s guest wireless network to download inappropriate material. Which of the following can the administrator do to MOST easily mitigate this issue?
Correct Answer:
A
Reducing the wireless power levels can limit the range of the guest wireless network and prevent users in an adjacent building from connecting to it. Adjusting the wireless channels or enabling wireless client isolation will not affect the signal strength or coverage of the guest network. Enabling wireless port security will not work on a guest network that does not use authentication or MAC address filtering. References: CompTIA Network+ Certification Exam Objectives Version 2.0 (Exam Number: N10-006), Domain 2.0 Network Operations, Objective 2.5 Given a scenario, implement appropriate wireless configuration settings; Guest WiFi Security - Cisco Umbrella
- (Topic 3)
A technician is troubleshooting a connectivity issue with an end user. The end user can access local network shares and intranet pages but is unable to access the internet or remote resources. Which of the following needs to be reconfigured?
Correct Answer:
C
- (Topic 1)
An engineer notices some late collisions on a half-duplex link. The engineer verifies that the devices on both ends of the connection are configured for half duplex. Which of the following is the MOST likely cause of this issue?
Correct Answer:
C
In a half-duplex link, devices can only send or receive data at one time, not simultaneously. Late collisions occur when devices transmit data at the same time after waiting for a clear channel. One of the causes of late collisions is excessive cable length, which increases the propagation delay and makes it harder for devices to detect collisions. The link termination, device configuration, and device hardware are not likely to cause late collisions on a half-duplex link.
- (Topic 3)
Which of the following combinations of single cables and transceivers will allow a server to have 40GB of network throughput? (Select two).
Correct Answer:
CD
QSFP+ is a type of transceiver that supports 40 gigabit Ethernet (40GbE) over four lanes of 10 gigabit Ethernet (10GbE) each. QSFP+ stands for quad small form-factor pluggable plus, and it is a compact and hot-swappable module that plugs into a QSFP+ port on a network device. QSFP+ transceivers can support various types of cables and connectors, such as direct attach copper (DAC), active optical cable (AOC), or fiber optic cable. Multimode is a type of fiber optic cable that supports multiple modes of light propagation within the core. Multimode fiber optic cable can carry higher bandwidth and data rates than single-mode fiber optic cable, but over shorter distances. Multimode fiber optic cable is commonly used for short-reach applications, such as within a data center or a campus network. Multimode fiber optic cable can be paired with QSFP+ transceivers to achieve 40GbE connectivity.
The other options are not correct because they do not support 40GbE. They are:
✑ SFP+. SFP+ is a type of transceiver that supports 10 gigabit Ethernet (10GbE) over a single lane. SFP+ stands for small form-factor pluggable plus, and it is a compact and hot-swappable module that plugs into an SFP+ port on a network device. SFP+ transceivers can support various types of cables and connectors, such as direct attach copper (DAC), active optical cable (AOC), or fiber optic cable. However, SFP+ transceivers cannot support 40GbE by themselves, unless they are used in a breakout configuration with a QSFP+ transceiver.
✑ SFP. SFP is a type of transceiver that supports 1 gigabit Ethernet (1GbE) over a single lane. SFP stands for small form-factor pluggable, and it is a compact and hot-swappable module that plugs into an SFP port on a network device. SFP transceivers can support various types of cables and connectors, such as twisted- pair copper, coaxial cable, or fiber optic cable. However, SFP transceivers cannot
support 40GbE by themselves, unless they are used in a breakout configuration with a QSFP+ transceiver.
✑ Cat 6a. Cat 6a is a type of twisted-pair copper cable that supports 10 gigabit
Ethernet (10GbE) over distances up to 100 meters. Cat 6a stands for category 6 augmented, and it is an enhanced version of Cat 6 cable that offers better performance and reduced crosstalk. Cat 6a cable can be paired with 10Gbase-T transceivers to achieve 10GbE connectivity. However, Cat 6a cable cannot support 40GbE by itself, unless it is used in a breakout configuration with a QSFP+ transceiver.
✑ Cat 5e. Cat 5e is a type of twisted-pair copper cable that supports 1 gigabit
Ethernet (1GbE) over distances up to 100 meters. Cat 5e stands for category 5 enhanced, and it is an improved version of Cat 5 cable that offers better performance and reduced crosstalk. Cat 5e cable can be paired with 1000base-T transceivers to achieve 1GbE connectivity. However, Cat 5e cable cannot support 40GbE by itself, unless it is used in a breakout configuration with a QSFP+ transceiver.
References1: QSFP+ - an overview | ScienceDirect Topics2: Multimode Fiber - an overview | ScienceDirect Topics3: Network+ (Plus) Certification | CompTIA IT Certifications4: SFP+ - an overview | ScienceDirect Topics5: SFP - an overview | ScienceDirect Topics6: Cat 6a - an overview | ScienceDirect Topics7: [Cat 5e - an overview | ScienceDirect Topics]
