- (Topic 3)
Which of the following devices and encapsulations are found at the data link layer? (Select two).
Correct Answer:
BD
A frame is a unit of data that is transmitted at the data link layer of the OSI model. A frame consists of a header, a payload, and a trailer. The header contains information such as the source and destination MAC addresses, the frame type, and the error detection code. The payload contains the data from the upper layer protocols, such as IP packets. The trailer contains the frame check sequence, which is used to verify the integrity of the frame. A switch is a device that operates at the data link layer of the OSI model. A switch forwards frames based on the MAC addresses of the devices connected to its ports. A switch can create separate collision domains and reduce network congestion. A switch can also implement VLANs, which are logical groups of devices that share the same broadcast domain, regardless of their physical location. A session is a logical connection between two or more devices that allows the exchange of data at the transport layer of the OSI model. A session is not a device or an encapsulation at the data link layer. A firewall is a device that operates at the network layer or the application layer of the OSI model. A firewall filters packets based on the IP addresses, ports, protocols, or application rules. A firewall is not a device or an encapsulation at the data link layer. A packet is a unit of data that is transmitted at the network layer of the OSI model. A packet consists of a header and a payload. The header contains information such as the source and destination IP addresses, the protocol type, and the hop count. The payload contains the data from the upper layer protocols, such as TCP segments. A packet is not an encapsulation at the data link layer. A router is a device that operates at the network layer of the OSI model. A router forwards packets based on the IP addresses and the routing table. A router can create separate broadcast domains and connect different networks. A router is not a device or an
encapsulation at the data link layer. References: CompTIA Network+ N10-008 Cert Guide, Chapter 2, Section 2.2 and CompTIA Network+ N10-008 Cert Guide, Chapter 3, Section 3.1
- (Topic 3)
Which of the following documents dictates the uptimes that were agreed upon by the involved parties?
Correct Answer:
C
An SLA (Service Level Agreement) is a document that defines the expected level of service and performance guaranteed by a service provider to a customer. It usually specifies metrics such as uptime, availability, reliability, response time, and compensation or penalties for not meeting the agreed standards. An SLA is a way of ensuring that both parties are clear about their roles and responsibilities, and that the customer receives the quality of service they paid for.
- (Topic 3)
A help desk supervisor reviews the following excerpt of a call transcript:
Which of the following was the agent trying to accomplish with this exchange?
Correct Answer:
D
The agent was trying to duplicate the problem by asking the user to perform the same steps that led to the issue. This is a common troubleshooting technique that helps the agent to identify the root cause of the problem and verify if it is reproducible or intermittent. By duplicating the problem, the agent can also gather more information about the symptoms and error messages that the user encountered. References: [CompTIA Network+ Certification Exam Objectives], [Troubleshooting Methodology - CompTIA Network+ N10-007 - 1.4 | Professor Messer IT Certification Training Courses]
- (Topic 3)
A network technician is investigating a trouble ticket for a user who does not have network connectivity. All patch cables between the wall jacks and computers in the building were upgraded over the weekend from Cat 5 to Cat 6. The newly installed cable is crimped With a TIA/EIA 568A on one end and a TIA/EIA 568B on the other end. Which of the following should the technician do to most likely fix the issue?
Correct Answer:
B
Crimping the cable as a straight-through cable is the most likely fix for the issue where users are unable to access any network resources after upgrading from Cat 5 to Cat 6 cables. Crimping is a process of attaching connectors to the ends of cables using a tool called a crimper. A straight-through cable is a type of twisted-pair cable that has the same wiring scheme on both ends, meaning that each pin on one end is connected to the same pin on the other end. A straight-through cable is used to connect devices that operate on different layers of the OSI model, such as a computer and a switch, or a switch and a router. If the newly installed cable is crimped with TIA/EIA 568A on one end and TIA/EIA 568B on the other end, it becomes a crossover cable. A crossover cable is a type of twisted-pair cable that has opposite wiring schemes on both ends, meaning that each pin on one end is connected to a different pin on the other end. A crossover cable is used to connect devices that operate on the same layer of the OSI model, such as two computers or two switches. Using a crossover cable instead of a straight-through cable can cause network communication errors or failures. References: [CompTIA Network+ Certification Exam Objectives], Straight Through vs Crossover Cable: What’s The Difference?
- (Topic 3)
A computer engineer needs to ensure that only a specific workstation can connect to port 1 on a switch. Which of the following features should the engineer configure on the switch interface?
Correct Answer:
B
Port security is a feature that can be configured on a switch interface to limit and identify the MAC addresses of workstations that are allowed to connect to that specific port. This can help ensure that only a specific workstation (or workstations) can connect to the interface. According to the CompTIA Network+ Study Manual, “Port security can be used to specify which MAC addresses are allowed to connect to a particular switch port. If a port security violation is detected, the switch can take a number of different actions, such as shutting down the port, sending an SNMP trap, or sending an email alert.”