N10-009 Exam Dumps - CompTIA Network+ Certification Exam

A CNAME (Canonical Name) record is used in DNS to alias one domain name to another. This means that newapplication.comptia.org can be made to resolve to the same IP address as www.comptia.org by creating a CNAME record pointing newapplication.comptia.org to www.comptia.org . SOA (Start of Authority) is used for DNS zone information, MX (Mail Exchange) is for mail server records, and NS (Name Server) is for specifying authoritative DNS servers.

When a network interface's indicator lights are not blinking on either the computer or the switch, it suggests a physical layer issue. Here is the detailed reasoning:

Ethernet Properly Connected: The Ethernet cable is correctly connected, eliminating issues related to a loose or faulty cable.

No Indicator Lights: The absence of blinking indicator lights on both the computer and the switch typically points to the port being administratively shut down.

Switch Port Shut Down: In networking, a switch port can be administratively shut down, disabling it from passing any traffic. This state is configured by network administrators and can be verified and changed using the command-line interface (CLI) of the switch.

Command to Check and Enable Port:

bash

Copy code

Switch> enable

Switch# configure terminal

Switch(config)# interface [interface id]

Switch(config-if)# no shutdown

The command no shutdown re-enables the interface if it was previously disabled. This will restore the link and the indicator lights should start blinking, showing activity.

IPsec (Internet Protocol Security) is the most secure way to provide site-to-site connectivity. It provides robust security services, such as data integrity, authentication, and encryption, ensuring that data sent across the network is protected from interception and tampering. Unlike other options, IPsec operates at the network layer and can secure all traffic that crosses the IP network, making it the most comprehensive and secure choice for site-to-site VPNs.References: CompTIA Network+ study materials and NIST Special Publication 800-77.

Explanation: A /23 subnet provides 512 total addresses, of which 510 are usable (subtracting 2 for network and broadcast addresses). This would satisfy the need for 255 additional addresses.

Introduction to Subinterfaces:

Subinterfaces are logical interfaces created on a single physical interface. They are used to enable a router to support multiple networks on a single physical interface.

Use Case for Subinterfaces:

Subinterfaces are commonly used in scenarios where VLANs are implemented. A router with a single physical LAN port can be configured with multiple subinterfaces, each associated with a different VLAN.

This setup allows the router to route traffic between different VLANs.

Example Configuration:

Consider a router with a single physical interface GigabitEthernet0/0 and two VLANs, 10 and 20.

interface GigabitEthernet0/0.10

encapsulation dot1Q 10

ip address 192.168.10.1 255.255.255.0

!

interface GigabitEthernet0/0.20

encapsulation dot1Q 20

ip address 192.168.20.1 255.255.255.0

The encapsulation dot1Q command specifies the VLAN ID.

Explanation of the Options:

A. A router with only one available LAN port: This is correct. Subinterfaces allow a single physical interface to manage multiple networks, making it essential for routers with limited physical interfaces.

B. A firewall performing deep packet inspection: Firewalls can use subinterfaces, but it is not a requirement for deep packet inspection.

C. A hub utilizing jumbo frames: Hubs do not use subinterfaces as they operate at Layer 1 and do not manage IP addressing.

D. A switch using Spanning Tree Protocol: STP is a protocol for preventing loops in a network and does not require subinterfaces.

Conclusion:

Subinterfaces provide a practical solution for routing between multiple VLANs on a router with limited physical interfaces. They allow network administrators to optimize the use of available hardware resources efficiently.

References:

CompTIA Network+ guide detailing VLAN configurations and the use of subinterfaces (see page Ref 9†Basic Configuration Commands).

Importance of Proper Termination:

Cat 8 cabling requires precise termination practices to ensure signal integrity and reduce interference. One common requirement is to wrap the end connections in copper tape to maintain shielding and reduce electromagnetic interference (EMI).

Interference Troubleshooting:

Interference in high-frequency cables like Cat 8 can be caused by improper shielding or grounding. Checking the end connections for proper wrapping in copper tape is a crucial step.

Why Other Options are Less Likely:

Passthrough modular crimping plugs: Not specifically related to interference issues and are typically used for ease of cable assembly.

Connecting RX/TX wires to different pins: Would likely result in no connection or incorrect data transmission rather than interference.

Running a speed test on a device that can only achieve 100Mbps speeds: This would not diagnose interference and would not provide relevant information for Cat 8 cabling rated for higher speeds.

Corrective Actions:

Verify that all end connections are properly wrapped with copper tape before termination.

Ensure that the shielding is continuous and properly grounded throughout the installation.

Retest the cabling for interference after making corrections.

References:

CompTIA Network+ study materials and structured cabling installation guides.