Free Practice Questions for CompTIA N10-009 Exam

BGP (Border Gateway Protocol) uses an Autonomous System (AS) number for its operations. An AS is a collection of IP networks and routers under the control of a single organization that presents a common routing policy to the Internet. BGP is used to exchange routing information between different ASes on the Internet, making it the only protocol among the listed options that uses an AS number.References: CompTIA Network+ study materials and RFC 4271.

The customer can access local resources (a database server), which means local networking is working. However, the inability to reach the internet suggests an issue with the default gateway. If the default gateway is unreachable, packets will not be routed outside the local network.

Breakdown of Options:

A. Incorrect DNS – DNS issues would cause problems resolving domain names, but the user should still be able to access external resources via IP addresses.

B. Unreachable gateway – ✅ Correct answer. If the default gateway is incorrect or unreachable, the device cannot route traffic to the internet.

C. Failed root bridge – STP (Spanning Tree Protocol) failures cause switching issues, but the user can still access local devices, meaning STP is not the problem.

D. Poor upstream routing – Would affect the entire network, not just one user.

A Distributed Denial of Service (DDoS) attack leverages multiple computers or bots (botnet) to flood a target system with requests, overwhelming its resources and making it unavailable to legitimate users. This is a common tactic used by attackers to disrupt services. The document explains:

“A DDoS (Distributed Denial of Service) attack involves multiple computers (often called bots) simultaneously sending requests to a single resource, overwhelming the system and causing a denial of service to legitimate users.”

An IDS (Intrusion Detection System) is deployed out-of-band, meaning it passively monitors network traffic using a SPAN/mirror port or network tap. It detects and analyzes suspicious traffic without introducing latency since it does not sit in-line.

A. IPS (Intrusion Prevention System) is in-line and can block traffic but may add latency.

C. Load balancer distributes traffic across servers for performance and redundancy, not for threat detection.

D. Firewall filters traffic at the perimeter or internally; it can affect latency but does not provide the same in-depth attack analysis.

References (CompTIA Network+ N10-009):

Domain: Network Security — IDS vs. IPS, in-band vs. out-of-band monitoring, passive detection methods.

Comprehensive and Detailed Explanation (aligned to N10-009):

Multitenancy is a cloud concept where multiple customers share the same physical resources (servers, storage, and networks) but remain logically separated for security and privacy.

A. Elasticity is auto-scaling resources.

B. Hybrid cloud combines private and public resources.

C. Scalability is the ability to grow resources but doesn’t imply multiple customers.

References (CompTIA Network+ N10-009):

Domain: Networking Concepts — Cloud computing models, multitenancy in public cloud.

802.1Q tagging, also known as VLAN tagging, is used to identify VLANs on a trunk link between switches. This allows the switches to transfer data for multiple VLANs (or networks) over a single physical connection. This method ensures that traffic from different VLANs is properly separated and managed across the network.References: CompTIA Network+ study materials.

HTTP is an application-layer protocol, so the OSI layer that manages the exchange of HTTP information is Layer 7 (Application) . In the Network+ (N10-009) objectives, the OSI model is used to map common protocols to the layers where they operate. HTTP defines how web clients and servers format and exchange requests and responses (methods like GET/POST, headers, status codes, and message bodies). Those behaviors are part of the application services provided to end-user software such as web browsers, APIs, and web servers.

While HTTP relies on lower layers to function (for example, TCP at the Transport layer for reliable delivery and IP at the Network layer for addressing and routing), the protocol logic and meaning of the web transactions exist at the Application layer. The distractors do not fit: the Network layer handles IP routing, the Data Link layer handles frames and MAC addressing on local links, and the Session layer is associated with session establishment/management concepts but is not where HTTP is categorized for Network+ mapping. Therefore, Application is the correct answer.

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DNS poisoning (also commonly called DNS cache poisoning) is characterized by inserting fraudulent DNS data into a resolver’s cache so that subsequent queries return incorrect IP mappings. Option D describes this precisely: false DNS records are injected into a DNS server’s cache, causing users to be redirected to attacker-controlled destinations even when they request a legitimate hostname. This aligns with Network+ security objectives covering common network attacks targeting name resolution and trust relationships. Editing authoritative DNS records on a DNS server (A) implies direct compromise or unauthorized administrative change, which is a different scenario than cache poisoning. Setting up a malicious DNS server in place of a legitimate server (B) is closer to DNS hijacking or rogue DNS configuration rather than cache poisoning. Intercepting client requests and returning false responses (C) describes man-in-the-middle style spoofing on the wire; while related, the defining “poisoning” trait is the persistence created by corrupting the cache so the bad answer continues to be served. For defensive relevance in Network+ scope, cache poisoning highlights the importance of DNS security controls such as source port randomization, transaction ID entropy, and DNSSEC validation where applicable.