N10-009 Exam Dumps - CompTIA Network+ Questions and Answers

Role of the Hosts File:

The hosts file is a local file on a computer that maps hostnames to IP addresses. It can be used to override DNS resolution by providing a static mapping of a hostname to an IP address.

Common Issues with the Hosts File:

If an incorrect IP address is mapped to a hostname in the hosts file, it can cause the computer to resolve the hostname to the wrong IP address. This can lead to navigation issues for specific websites while other users, relying on DNS, do not face the same problem.

Why Other Options are Less Likely:

Self-signed certificate: Relates to SSL/TLS and would cause a security warning, not a navigation failure.

Nameserver record: Affects all users, not just one.

IP helper: Used to forward DHCP requests and is unrelated to DNS resolution issues.

Troubleshooting Steps:

Check the hosts file on the affected user's computer (C:\Windows\System32\drivers\etc\hosts on Windows or /etc/hosts on Unix/Linux).

Look for entries that map the problematic hostname to an incorrect IP address and correct or remove them.

•nslookup allows querying DNS records to verify if the new server is correctly resolving domain names.

•ping (A) tests basic connectivity, not DNS configuration.

•tracert (B) shows network path latency but doesn’t test DNS.

•tcpdump (C) captures packets but isn’t ideal for DNS verification.

????Reference: CompTIA Network+ N10-009 Official Documentation – DNS Testing Tools.

Site-to-Site VPN: A site-to-site VPN is used to securely connect two networks, such as a company's headquarters and a branch location, over the internet. This type of VPN creates a secure tunnel for data transmission, ensuring confidentiality and integrity.

Split-tunnel VPN (A): Allows some traffic to bypass the VPN tunnel, which may not secure all communications.

Clientless VPN (B): Used for individual users to access the network without VPN client software.

Full-tunnel VPN (C): Typically used for individual user traffic rather than connecting two networks.

API gateways offer programmable control and real-time communication, commonly over HTTPS, which allows administrators to update and manage devices like access points remotely and efficiently.

From Andrew Ramdayal’s guide:

“APIs enable automation and real-time interaction with network devices via secure interfaces, often using HTTPS for encrypted communication and control.”

Availability refers to ensuring that data is accessible when needed. If a customer's data is accidentally deleted, it impacts availability, as the data can no longer be accessed.

=================

Understanding Multicast:

Multicast IP Address Range: The multicast address range is from 224.0.0.0 to 239.255.255.255, designated for multicast traffic.

Multicast Applications:

Use Case: Multicast is used for one-to-many or many-to-many communication, suitable for applications like audio and video broadcasting where the same data is sent to multiple recipients simultaneously.

Appropriate Network Selection:

224.0.0.0/24 Network: This range is reserved for multicast addresses, making it the appropriate choice for setting up a multicast network.

Comparison with Other Options:

172.16.0.0/24: Part of the private IP address space, used for private networks, not designated for multicast.

192.168.0.0/24: Another private IP address range, also not for multicast.

240.0.0.0/24: Reserved for future use, not suitable for multicast.

When traffic moves laterally between VMs within the same network or subnet, it is known as east-west traffic. This contrasts with north-south traffic, which refers to communication between internal and external networks.

Breakdown of Options:

A. East-west – Correct answer. This refers to traffic between internal servers or VMs, which is a common security concern.

B. Point-to-point – Point-to-point describes a direct connection between two devices, but does not specifically define lateral movement.

C. Horizontal-scaling – This refers to adding more instances or nodes in cloud computing, unrelated to traffic flow.

D. Hub-and-spoke – This network topology describes a centralized design, not lateral traffic.

Multimode fiber optic cables involve the transmission of light signals that bounce off the core's cladding as they travel down the fiber. This characteristic differentiates it from single-mode fiber, where the light travels directly down the fiber without reflecting off the cladding.

Here are some detailed points about multimode fiber cables:

Construction: Multimode fibers have a larger core diameter, typically 50 or 62.5 microns, compared to single-mode fibers, which have a core diameter of about 9 microns.

Light Propagation: The larger core of multimode fiber allows multiple light modes to propagate. These modes travel at different angles, leading to reflections off the core-cladding boundary.

Distance and Bandwidth: Due to modal dispersion, where different light modes arrive at the receiver at different times, multimode fibers are suited for shorter distance applications compared to single-mode fibers. Typical distances are up to 550 meters for 10 Gbps Ethernet using OM4 multimode fiber.

Applications: Multimode fibers are commonly used in LANs (Local Area Networks), data centers, and for shorter distance data transmission due to their cost-effectiveness and ease of installation.

Network References:

CompTIA Network+ N10-007 Official Certification Guide, which covers fiber optic technologies, including the differences between multimode and single-mode fibers.

Cisco Networking Academy: Provides training materials and reference guides on the properties of different fiber optic cables.

Fiber Optic Association (FOA): A professional society dedicated to fiber optics, offering extensive information and certification on fiber optic technologies.

Multimode fibers are specifically designed for short-range communication with higher data rates and are typically used in environments like data centers, where high bandwidth over shorter distances is crucial. The reflections off the cladding, inherent to multimode fiber, facilitate this high-capacity communication.