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Question 101

What is the default bridge priority value assigned to Cisco switches for Spanning Tree Protocol?

1. 4096
2. 8192
3. 16384
4. 32768

Correct Answer: 4

Explanation:

In standard Spanning Tree Protocol implementations on Cisco switches, the default bridge priority value is universally configured as 32768. This mid-range value allows switches to participate in the root bridge election process fairly, ensuring that a switch can become either the root bridge or a non-root bridge depending on whether its priority or MAC address is lower than competing devices. Network administrators frequently modify this default priority value—typically decrementing it in increments of 4096 utilizing extended system ID VLAN configurations—to manually designate specific core switches as the primary or secondary root bridges within enterprise network topologies.

Question 102

Which protocol provides secure file transfer capabilities over an encrypted SSH connection?

1. Trivial File Transfer Protocol
2. Secure File Transfer Protocol
3. File Transfer Protocol
4. Hypertext Transfer Protocol Secure

Correct Answer: 2

Explanation:

Secure File Transfer Protocol is a network protocol designed to provide secure file transfer, file management, and file access capabilities over any reliable data stream. Unlike legacy File Transfer Protocol, which transmits authentication credentials and data payloads in clear text across insecure networks, SFTP operates as a subsystem of Secure Shell, leveraging its robust encryption mechanisms. All data streams, passwords, and file contents are fully encrypted during transit, protecting sensitive organizational files against eavesdropping, interception, and tampering by malicious actors across both local and wide area networks.

Question 103

What IPv4 prefix length corresponds to a subnet mask of 255.255.255.192?

1. /24
2. /25
3. /26
4. /27

Correct Answer: 3

Explanation:

CIDR notation utilizes a slash followed by a number to represent the total number of contiguous network bits set to binary one within an IPv4 subnet mask. A subnet mask of 255.255.255.192 breaks down in binary as 11111111.11111111.11111111.11000000. Counting the total number of active network bits yields twenty-four bits for the first three octets plus two active bits in the final octet, totaling twenty-six bits. This /26 prefix divides a major network into four subnets with sixty-four total addresses each, yielding sixty-two usable host IPs per subnet.

Question 104

Which networking device operates primarily at Layer 3 to forward packets across disparate networks?

1. Layer 2 Switch
2. Network Hub
3. Enterprise Router
4. Passive Patch Panel

Correct Answer: 3

Explanation:

An enterprise router operates primarily at Layer 3, the network layer of the OSI reference model. Its core responsibility is to examine incoming data packets, analyze destination IP addresses, evaluate routing tables and dynamic routing protocols, and forward packets across disparate network segments. Unlike Layer 2 switches that manage traffic within a single local area network using hardware MAC addresses, Layer 3 routers bridge distinct networks together, perform packet encapsulation adjustments, enforce security filtering, and manage traffic flow across wide area connections, making them foundational pillars of internetwork routing architecture.

Question 105

What is the primary function of the Address Resolution Protocol cache?

1. Storing mappings of logical IPv4 addresses to physical MAC addresses.
2. Caching domain name translation entries to speed up web browsing.
3. Recording active routing table paths learned from dynamic protocols.
4. Saving configuration files in non-volatile random access memory.

Correct Answer: 1

Explanation:

The Address Resolution Protocol cache is a temporary memory table maintained by operating systems and network devices that stores recently resolved pairings of logical Layer 3 IPv4 addresses and physical Layer 2 MAC addresses. When a host needs to transmit data to another device on the local network, it checks its local ARP cache first. If a valid entry exists, the device bypasses the ARP broadcast request process and immediately constructs the Ethernet frame, significantly reducing local network traffic overhead and accelerating frame transmission efficiency.

Question 106

Which transport layer protocol is connectionless and does not guarantee reliable delivery?

1. Transmission Control Protocol
2. User Datagram Protocol
3. Secure Shell Protocol
4. File Transfer Protocol

Correct Answer: 2

Explanation:

The User Datagram Protocol is a core transport layer protocol characterized by its connectionless nature and minimal protocol overhead. Unlike Transmission Control Protocol, UDP does not execute a three-way handshake before transmitting data, nor does it provide sequencing, flow control, error recovery, or retransmission of lost packets. Applications such as Domain Name System lookups, voice over IP streaming, and video broadcasting utilize UDP because speed and low latency are prioritized over guaranteed, error-checked packet delivery.

Question 107

Which Cisco IOS command displays active spanning tree operational status and port states?

1. show ip route
2. show running-config
3. show spanning-tree
4. show interfaces brief

Correct Answer: 3

Explanation:

The show spanning-tree command is a vital diagnostic command executed within the Cisco IOS command-line interface to inspect the current state of the Spanning Tree Protocol across a switched network. When entered in privileged EXEC mode, it displays the root bridge identifier for each active VLAN, local bridge priority settings, designated port roles, and physical interface states such as forwarding, blocking, listening, or learning. Network engineers rely on this command to verify loop-free topology convergence, troubleshoot blocked port bottlenecks, and validate redundancy configurations.

Question 108

Which copper cable category introduced stricter performance standards for near-end crosstalk compared to Cat5?

1. Category 3
2. Category 5e
3. Category 6a
4. Category 8

Correct Answer: 2

Explanation:

Category 5e unshielded twisted pair copper cabling was introduced to improve upon legacy Category 5 specifications by enforcing much stricter performance standards for signal attenuation, return loss, and near-end crosstalk. These enhancements enable Cat5e cabling to support full-duplex Gigabit Ethernet data transmission speeds across all four wire pairs simultaneously up to 100 meters. While Cat5 supported 100 Mbps data rates, Cat5e became the mandatory baseline for enterprise local area network deployments requiring reliable 1000 Mbps throughput capacity.

Question 109

What is the maximum allowable permanent link length for standard UTP copper cabling?

1. 50 meters
2. 90 meters
3. 100 meters
4. 185 meters

Correct Answer: 2

Explanation:

According to ANSI/TIA structured cabling standards, the maximum allowable length for a permanent horizontal solid-core UTP copper link installed within building walls or conduits is 90 meters. When combined with a maximum of 10 meters of stranded patch cables utilized at both the telecommunications room patch panel and the workstation end, the total channel length cannot exceed the 100-meter threshold. Exceeding this 90-meter permanent link limit introduces excessive signal attenuation and jitter, leading to high bit error rates and packet loss.

Question 110

Which IEEE standard defines Virtual Local Area Network frame tagging on Ethernet links?

1. IEEE 802.3
2. IEEE 802.1Q
3. IEEE 802.11
4. IEEE 802.1X

Correct Answer: 2

Explanation:

The IEEE 802.1Q standard specifies the protocol for Virtual Local Area Network bridge operation and frame tagging across Ethernet networks. To allow a single physical trunk link to carry traffic belonging to multiple distinct VLANs simultaneously, switches insert a 4-byte 802.1Q VLAN tag into the Ethernet frame header. This tag contains a 12-bit VLAN identifier field that enables receiving switches to distinguish which VLAN a frame belongs to, ensuring proper segmentation and traffic isolation across shared physical infrastructure.

Question 111

What DNS record type is utilized to perform reverse lookups mapping IP addresses to hostnames?

1. A Record
2. AAAA Record
3. PTR Record
4. MX Record

Correct Answer: 3

Explanation:

A Pointer record, commonly referred to as a PTR record, is utilized within Domain Name System architecture to perform reverse DNS lookups, translating a numerical IPv4 or IPv6 address back into its corresponding human-readable fully qualified domain name. While standard A records map names to IPv4 addresses and AAAA records map names to IPv6 addresses, PTR records are critical for security logging, email server authentication, and network diagnostic tools like traceroute, which resolve router IP addresses into descriptive hostnames.

Question 112

Which IPv6 address range is designated for Unique Local Addresses?

1. fe80::/10
2. fc00::/7
3. 2000::/3
4. ff00::/8

Correct Answer: 2

Explanation:

Unique Local Addresses in IPv6 are designed for local communications within an organization or across a limited set of administrative domains, operating similarly to private IPv4 address spaces defined in RFC 1918. ULA addresses utilize the reserved prefix fc00::/7, with the locally assigned global ID subrange typically utilizing fd00::/8. These addresses are routable within internal enterprise networks but are strictly non-routable across the public global internet, providing internal isolation and privacy protection.

Question 113

What is the default administrative distance assigned to Routing Information Protocol?

1. 1
2. 90
3. 110
4. 120

Correct Answer: 4

Explanation:

Administrative distance represents the trustworthiness or preference level of a routing information source, where lower values indicate higher reliability in path selection. In Cisco IOS routing architecture, the Routing Information Protocol is assigned a default administrative distance of 120. This value positions RIP as less preferred than OSPF at 110, internal EIGRP at 90, and static routes at 1. Understanding these default values is crucial for network engineers designing multi-protocol routing environments and migration strategies.

Question 114

Which switching method reads the first six bytes of a frame to examine the destination MAC address before forwarding?

1. Store-and-forward switching
2. Cut-through switching
3. Fragment-free switching
4. CRC validation switching

Correct Answer: 2

Explanation:

In cut-through switching, the switch reads only the first six bytes of an incoming Ethernet frame—specifically the destination MAC address—and immediately looks up its internal forwarding table to route the frame out the appropriate egress port without waiting for the rest of the frame to arrive. This method minimizes latency significantly compared to store-and-forward switching. However, because cut-through switches do not buffer the entire frame or perform Cyclic Redundancy Check validation, they can inadvertently propagate corrupted frames and runt collisions across the network.

Question 115

What is the primary purpose of the Frame Check Sequence field in an Ethernet frame?

1. Identifying the source hardware MAC address of the transmitting node.
2. Detecting transmission errors and corrupted data bits via CRC calculation.
3. Indicating the upper layer protocol encapsulated within the data payload.
4. Designating the specific VLAN identifier tag for trunk routing.

Correct Answer: 2

Explanation:

The Frame Check Sequence is a 4-byte trailer located at the very end of an Ethernet frame that contains a Cyclic Redundancy Check mathematical value. When a network device utilizing store-and-forward switching receives an Ethernet frame, it recalculates the CRC value based on the frame contents and compares it against the FCS trailer value. If the mathematical calculations match, the frame is verified as error-free; if they mismatch, indicating electrical noise or interference during transit, the switch drops the corrupted frame immediately.

Question 116

Which Cisco IOS command displays active routing protocol parameters, timers, and metrics?

1. show ip route
2. show ip protocols
3. show ip interface brief
4. show running-config

Correct Answer: 2

Explanation:

The show ip protocols command is a specialized diagnostic tool executed within the Cisco IOS command-line interface to inspect active routing protocols currently running on a router. When executed in privileged EXEC mode, it displays critical operational telemetry including routing protocol types, autonomous system numbers, router IDs, network statements being advertised, metric weights, default administrative distances, update timers, and neighbor routing sources. Network engineers utilize this command during troubleshooting to verify that dynamic routing protocols are configured correctly and exchanging updates.

Question 117

Which layer of the OSI model is responsible for data compression, encryption, and formatting?

1. Physical Layer
2. Transport Layer
3. Presentation Layer
4. Application Layer

Correct Answer: 3

Explanation:

The Presentation layer, which is Layer 6 of the OSI reference model, is responsible for ensuring that data sent from the application layer of one system can be read and interpreted by the application layer of another system. This layer handles data formatting, syntax translation, character set conversion, data compression, and cryptographic encryption or decryption services. By standardizing data representation formats, the presentation layer abstracts underlying operating system differences and ensures secure, compatible data exchanges across heterogeneous network environments.

Question 118

Which dynamic routing protocol utilizes link-state advertisements and Dijkstra’s shortest path first algorithm?

1. Routing Information Protocol
2. Enhanced Interior Gateway Routing Protocol
3. Open Shortest Path First
4. Border Gateway Protocol

Correct Answer: 3

Explanation:

Open Shortest Path First is an open-standard link-state routing protocol that operates within an autonomous system. Rather than sharing simple distance vectors with neighbors, OSPF routers flood link-state advertisements to all peers within an area, building a complete topological map of the entire network. Each router then independently executes Dijkstra’s shortest path first algorithm to calculate the optimal loop-free path to every destination network, resulting in rapid convergence times and efficient metric utilization.

Question 119

What protocol automates IP address assignment using a discover, offer, request, and acknowledgment workflow?

1. Domain Name System
2. Dynamic Host Configuration Protocol
3. Address Resolution Protocol
4. Network Time Protocol

Correct Answer: 2

Explanation:

The Dynamic Host Configuration Protocol automates network configuration for client devices through a four-step communication process known as the DORA workflow. When a client connects to the network, it broadcasts a DHCP Discover message. Available DHCP servers respond with a DHCP Offer containing lease parameters. The client selects an offer and replies with a DHCP Request, and the server concludes the process with a DHCP Acknowledgment, finalizing the lease allocation of the IP address, subnet mask, and default gateway.

Question 120

Which traditional networking device operates strictly at Layer 1 and simply regenerates electrical signals?

1. Layer 2 Switch
2. Enterprise Router
3. Network Hub
4. Multilayer Switch

Correct Answer: 3

Explanation:

A traditional network hub operates strictly at Layer 1, the physical layer of the OSI reference model. When a hub receives an electrical or optical signal on one of its ports, it simply regenerates that signal and broadcasts it out all other active ports without examining header information, MAC addresses, or packet contents. Because hubs do not filter traffic or establish separate collision domains, all connected devices share a single collision domain and a single broadcast domain, leading to increased contention, potential frame collisions, and performance degradation in busy network environments.