N10-009 Exam Dumps - CompTIA Network+ Certification Exam

Understanding Subnetting:

Original Network: 192.168.1.0/24 has a subnet mask of 255.255.255.0, which allows for 256 IP addresses (including network and broadcast addresses).

Objective: Divide this network into two equal subnets.

Calculating Subnet Mask:

New Subnet Mask: To divide 192.168.1.0/24 into two equal halves, we need to borrow one bit from the host portion of the address, changing the subnet mask to 255.255.255.128 (/25).

Subnet Breakdown:

First Subnet: 192.168.1.0/25 (192.168.1.0 - 192.168.1.127)

Second Subnet: 192.168.1.128/25 (192.168.1.128 - 192.168.1.255)

Verification:

Each subnet now has 128 IP addresses (126 usable IP addresses, excluding the network and broadcast addresses).

Comparison with Other Options:

255.255.0.0 (/16): Provides a much larger network, not dividing the original /24 network.

255.255.254.0 (/23): Also creates a larger subnet, encompassing more than the original /24 network.

255.255.255.0 (/24): Maintains the original subnet size, not dividing it.

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.”

A Change Advisory Board (CAB) reviews and approves network changes. Before approval, they need a detailed action plan outlining the change, potential impacts, and mitigation strategies.

A Plan of Action includes risk assessments, rollback procedures, and deployment steps, which are critical for decision-making.

? Reference: CompTIA Network+ (N10-009) Official Study Guide – Section: Network Troubleshooting Methodologies

An evil twin attack occurs when an attacker creates a fraudulent AP with an SSID very similar (or identical) to the legitimate one. Users may accidentally connect, allowing the attacker to capture traffic and credentials.

A. On-path is the consequence of connecting to the evil twin, not the initial attack itself.

B. Rogue AP is any unauthorized access point, but the key here is the malicious mimicry of a legitimate SSID — specifically an evil twin.

D. Tailgating is a physical social engineering attack, unrelated to Wi-Fi.

References (CompTIA Network+ N10-009):

Domain: Network Security — Wireless threats (rogue APs, evil twins).

Understanding End-of-Support:

End-of-Support Status: When a vendor declares a device as end-of-support, it means the device will no longer receive updates, patches, or technical support. This poses a security risk as new vulnerabilities will not be addressed.

Risks of Keeping an End-of-Support Device:

Security Vulnerabilities: Without updates, the switch becomes susceptible to new security threats.

Compliance Issues: Many regulatory frameworks require that critical infrastructure be maintained with supported and secure hardware.

Best Next Step - Replacement:

Decommission and Replace: The most secure approach is to replace the end-of-support switch with a new, supported model. This ensures the infrastructure remains secure and compliant with current standards.

Planning and Execution: Plan for the replacement by evaluating the network's needs, selecting a suitable replacement switch, and scheduling downtime for the hardware swap.

Comparison with Other Options:

Apply the Latest Patches: While helpful, this does not address future vulnerabilities since no further patches will be provided.

Ensure the Current Firmware Has No Issues: This is only a temporary measure and does not mitigate future risks.

Isolate the Switch from the Network: Isolating the switch may disrupt network operations and is not a viable long-term solution.

Multi-factor authentication (MFA) requires two or more different categories of authentication factors:

Something you know (password, PIN)

Something you have (smart card, hardware token)

Something you are (biometric)

The only valid second factor here is a hard token (e.g., a key fob generating one-time codes).

A. PIN is still “something you know,” the same category as a password.

B. Favorite color is a weak knowledge-based factor, not a true second factor.

D. Mother’s maiden name is also “something you know” and insecure.

References (CompTIA Network+ N10-009):

Domain: Network Security — Authentication methods, MFA factor categories.

BNC (Bayonet Neill–Concelman) connectors are commonly used with coaxial cables in RF and wireless applications, including some older Wi-Fi antennas and specialized networking equipment. The document says:

“BNC (Bayonet Neill–Concelman) connectors are typically used with coaxial cables, especially in radio frequency (RF) and some Wi-Fi antenna applications, providing a secure and quick connect/disconnect.”

Understanding TTL (Time to Live):

TTL is a value in a DNS record that tells how long that record should be cached by DNS servers and clients. A higher TTL value means that the record will be cached longer, reducing the load on the DNS server but delaying the propagation of changes.

Impact of TTL on DNS Changes:

When an MX record change is made, it may take time for the change to propagate across all DNS servers due to the TTL setting. If the TTL is high, old DNS information might still be cached, leading to email being directed to the old server.

Best Practice Before Making DNS Changes:

To ensure that changes to DNS records propagate quickly, it is recommended to reduce the TTL value to a lower value (such as 300 seconds or 5 minutes) well in advance of making the changes. This ensures that any cached records will expire quickly, and the new records will be used sooner.

Verification of DNS Changes:

After reducing the TTL and making the change to the MX record, it is important to verify the propagation using tools like dig or nslookup.

Comparison with Other Options:

Change the email client configuration to match the MX record: Email clients generally do not need to match the MX record directly; they usually connect to a specific mail server specified in their settings.

Perform a DNS zone transfer prior to the MX record change: DNS zone transfers are used to replicate DNS records between DNS servers, but they are not related to the propagation of individual record changes.

Update the NS record to reflect the IP address change: NS records specify the DNS servers for a domain and are not related to MX record changes.