Solution :
251020261026064745 Correct Answer : PAN < LAN < MAN < WAN

Description -

The correct order is PAN < LAN < MAN < WAN.

Explanation of Network Types

• PAN (Personal Area Network): This is the smallest network, centered around a single person in a single location. It typically covers a range of under 10 metres (e.g., connecting your smartphone to your wireless earbuds via Bluetooth).
• LAN (Local Area Network): This network connects computers and devices within a limited localized area, such as a single room, home, office building, or school. It typically covers up to a few hundred metres.
• MAN (Metropolitan Area Network): This network covers a larger geographic area than a LAN, typically spanning an entire city or town. A common example is a city's cable television network or a large university campus network.
• WAN (Wide Area Network): This is the largest type of network, extending over a vast geographical area such as countries, continents, or the entire globe. The Internet is the most well-known example of a WAN.

Solution :
960420260322103411 Correct Answer : High complexity and maintenance cost

Description -

The correct answer is High complexity and maintenance cost.

Why this is a disadvantage

• High complexity and maintenance cost: Setting up a Wide Area Network (WAN) requires expensive infrastructure, such as leased lines, satellites, and advanced networking hardware (like enterprise routers and switches). Because it spans vast distances (across cities, countries, or continents), it requires dedicated IT teams to manage, monitor, and troubleshoot issues, making the maintenance costs very high.

Why the other options are incorrect

• Limited coverage: Broad geographical coverage is the primary advantage of a WAN, not a disadvantage.
• Low cost: WANs are highly expensive to establish and maintain compared to LANs or PANs.
• Very high security: While security measures are heavily implemented, managing security across global public and private networks is incredibly difficult, making WANs more vulnerable to cyberattacks than localized networks.

Solution :
240620260322103324 Correct Answer : CAN

Description -

The correct answer is CAN (Campus Area Network).

Why CAN is the most suitable

• CAN (Campus Area Network): This network type is specifically designed to connect multiple localized networks (LANs) across a defined geographical area, such as a university campus, corporate park, or military base. It is larger than a single LAN (which usually covers just one building) but smaller and more localized than a MAN (which covers an entire city).

Why the other options are less suitable

• PAN (Personal Area Network): Way too small. It only covers the immediate space around a single person (under 10 metres).
• LAN (Local Area Network): Typically restricted to a single building, home, or office. While a university campus is made of many LANs, the network linking them together becomes a CAN.
• WAN (Wide Area Network): Too large and complex. WANs connect systems across different cities, countries, or continents (like the Internet). Using it for a single university campus would be unnecessary and highly inefficient.

Solution :
480820260322103241 Correct Answer : It covers large geographic areas like countries or continents

Description -

The correct answer is It covers large geographic areas like countries or continents.

Why this statement is correct

• It covers large geographic areas like countries or continents: The primary defining characteristic of a Wide Area Network (WAN) is its massive geographical reach. It connects smaller networks (like LANs and MANs) across vast distances, with the Internet being the largest and most well-known example of a WAN.

Why the other options are incorrect

• It is limited to a single building: This describes a LAN (Local Area Network), not a WAN.
• It has the highest speed among all networks: Due to the vast distances data must travel and the congestion on public infrastructure, WANs generally have slower data transfer speeds and higher latency compared to localized networks like LANs.
• It is cheaper than LAN: Setting up and maintaining a WAN requires expensive long-distance infrastructure (like satellites, undersea cables, and leased lines), making it far more expensive than a LAN.

Solution :
555820260322103145 Correct Answer : PAN

Description -

The correct answer is PAN (Personal Area Network).

Why PAN uses these technologies

• PAN (Personal Area Network): This network type centers around an individual person's immediate workspace, typically spanning a range of less than 10 metres. Bluetooth and NFC (Near Field Communication) are short-range wireless technologies specifically engineered to connect personal devices—such as pairing your smartphone with wireless earbuds, syncing a smartwatch, or making a contactless tap-to-pay transaction.

Why the other options are incorrect

• LAN (Local Area Network): Typically uses technologies like Ethernet cables or Wi-Fi (802.11) to cover an entire room, home, or office building.
• WAN (Wide Area Network): Uses long-range technologies such as leased telecommunication lines, fiber-optic undersea cables, and satellites to connect countries or continents.
• MAN (Metropolitan Area Network): Spans an entire city and commonly relies on Fiber-optic cables, microwave links, or WiMAX

Solution :
460720260322103049 Correct Answer : Connects multiple LANs across a city

Description -

The correct answer is Connects multiple LANs across a city.

Why this option best describes a MAN

• Connects multiple LANs across a city: A Metropolitan Area Network (MAN) is explicitly designed to cover a geographic area larger than a single building (LAN) but smaller than a country or continent (WAN). It typically spans an entire town, city, or large municipality by interconnecting various local networks (such as police stations, bank branches, or corporate offices within the same city).

Why the other options are incorrect

• Connects devices within a single room: This describes a LAN (or even a PAN, depending on the scale).
• Connects devices globally via satellites: This describes a WAN (Wide Area Network).
• Connects personal devices using Bluetooth: This describes a PAN (Personal Area Network).

Solution :
546120260322102906 Correct Answer : Bus topology

Description -

The correct answer is Bus topology.

Why Bus topology matches this description

• Bus topology: In this configuration, all nodes (computers and peripherals) are connected to a single, central communication cable called the "bus" or "backbone." Data travels along the cable in both directions. If this main cable breaks or gets cut anywhere along the line, the entire network fails immediately because the electrical signal can no longer terminate properly, causing signal reflection and breaking the communication path for all devices.

Why the other options are incorrect

• Ring topology: Devices are connected in a circular loop. Data travels in one direction from device to device. While a break in the ring can bring down the network, it does not use a single shared central backbone cable.
• Mesh topology: Every device is interconnected with multiple redundant paths to other devices. It is highly fault-tolerant; if one cable fails, data is simply rerouted through another path, so the network never goes down.
• Tree topology: A hierarchical structure combining elements of star and bus topologies. While a failure of a root cable can isolate branches, it is organized in levels rather than a single shared line for every single device.

Solution :
215720260322102821 Correct Answer : Central hub failure affects entire network

Description -

The correct answer is Central hub failure affects entire network.

Why this is the major disadvantage

• Central hub failure affects entire network: In a star topology, every single device (computer, printer, etc.) is connected directly to a central connection point, such as a hub, switch, or router. Because all data communication must pass through this central device, it acts as a single point of failure. If the central hub or switch breaks down, the entire network crashes immediately, and no devices can communicate with each other.

Why the other options are incorrect

• Difficult to expand: Star topology is actually very easy to expand. You can simply plug a new device into an open port on the central hub without disrupting the rest of the network.
• High collision rate: Modern star topologies use switches instead of hubs, which creates dedicated communication channels for each device and drastically reduces or eliminates data collisions.
• Requires excessive routing: Data goes directly from the sending device to the central hub, and then straight to the receiving device. It does not require complex or excessive routing pathways like a mesh topology.

Solution :
271020260322102723 Correct Answer : Star topology

Description -

The correct answer is Star topology.

Why Star topology matches this description

• Star topology: As discussed, every computer and device on a star network connects directly to a central node, such as a switch or hub. Because this central device acts as the single gateway for all network traffic, its failure instantly paralyzes the entire network.

Why the other options are incorrect

• Bus topology: The single point of failure here is the main backbone cable, not a central device.
• Mesh topology: Highly redundant; every node has multiple dedicated links to other nodes, completely eliminating single points of failure.
• Ring topology: Every device is connected to its two immediate neighbours in a loop. A failure of any individual workstation or its direct connection cable breaks the loop, rather than a central device failure.

Solution :
322720260322102633 Correct Answer : Tree topology

Description -

The correct answer is Tree topology.

Why Tree topology matches this description

• Tree topology: This topology features a hierarchical structure that looks like an inverted tree or organizational chart. It consists of multiple star networks connected together via a central linear bus backbone cable. A main root node branches down to secondary hubs, which then branch down to individual computers.

Why the other options are incorrect

• Ring topology: Devices are connected in a continuous circular loop. It has no hierarchy and does not combine star and bus structures.
• Mesh topology: Every device is interconnected via point-to-point links. It forms a web-like pattern rather than a hierarchical structure.
• Hybrid topology: While a tree topology is technically a specific type of hybrid network, "Tree topology" is the exact, standard textbook term for a network that specifically combines a bus backbone with star clusters in a hierarchical layout.

Solution :
783620260322102539 Correct Answer : Tree topology

Description -

The correct answer is Tree topology.

Why Tree topology matches this description

• Tree topology: This topology is explicitly defined by its hierarchical structure, which resembles the branches of a tree. It directly combines features of star and bus topologies by connecting multiple star networks (groups of devices connected to a central hub) along a main linear bus backbone cable.

Why the other options are incorrect

• Hybrid topology: While a tree network is technically a type of hybrid architecture because it mixes two layouts, "Tree topology" is the specific and standard textbook term for a combination that follows a strict hierarchical (parent-child)
• Mesh topology: Devices are interconnected with multiple redundant paths in a web-like configuration rather than a top-down hierarchy.
• Ring topology: Devices are connected in a continuous circular loop where data flows sequentially from one node to the next.

Solution :
838720260322102419 Correct Answer : Bus topology

Description -

The correct answer is Bus topology.

Why Bus topology matches this description

• Bus topology: In a bus network, every computer and device connects to a single, central communication cable called the "bus" or "backbone." If this main backbone cable breaks, gets cut, or loses its termination points at the ends, the entire network fails instantly because the electrical path is broken and signals can no longer travel between any devices.

Why the other options are incorrect

• Star topology: The single point of failure is the central hub or switch. If an individual cable breaks, only the device connected to that specific cable goes down.
• Mesh topology: This layout provides maximum redundancy. Devices have multiple connection paths, so if one cable fails, the data is simply rerouted through another path.
• Tree topology: A tree topology uses a backbone cable to connect different star network branches. While a break in the root backbone cable is severe, it typically splits the network into functioning segments rather than causing every single internal device to fail completely.

Solution :
746620260322102315 Correct Answer : Ring topology

Description -

The correct answer is Ring topology.

Why Ring topology matches this description

• Ring topology: In this configuration, devices are connected in a continuous, closed loop. Data travels sequentially from one node to the next in a circular path (usually in one direction). To eliminate data collisions, it uses a protocol called token passing. A small frame called a "token" constantly circulates around the ring; a device can only transmit data when it catches the free token, ensuring that only one device talks at a time.

Why the other options are incorrect

• Bus topology: Data travels back and forth along a single linear cable rather than a circular loop. It relies on CSMA/CD to handle collisions rather than token passing.
• Star topology: Devices radiate outward from a central switch or hub. Modern star networks use switches to segregate traffic into distinct collision domains, eliminating collisions without using a token.
• Tree topology: A top-down hierarchical structure connecting groups of star networks via a bus backbone, which does not use a circular data loop.

Solution :
726520260322101949 Correct Answer : Mesh

Description -

The correct answer is Mesh.

Why Mesh topology matches this description

• Mesh topology: In a full mesh network, every single node is connected directly to every other node via dedicated point-to-point links. This configuration creates multiple redundant paths for data to travel. Because of this high redundancy, it offers unmatched fault tolerance—if one cable or device fails, the system automatically reroutes traffic through an alternate path, ensuring the network stays up.

Why the other options are incorrect

• Bus: Uses a single central cable. It has no redundant pathways; if the main cable fails, the entire network crashes.
• Star: Every device connects to a central hub or switch. If the central device fails, the whole network goes down. There are no alternate routes between nodes.
• Ring: Devices are connected in a circular loop. In a standard single-ring setup, a failure of just one node or cable breaks the loop and halts communication.

Solution :
743620260322101854 Correct Answer : Mesh topology

Description -

The correct answer is Mesh topology.

Why Mesh topology matches this description

• Mesh topology: In a full mesh network, every single device has a dedicated point-to-point physical connection to every other device. Because each node requires its own unique link to all other nodes, it consumes the maximum amount of cabling among all configurations. The total number of physical links needed to connect \(n\) devices is calculated using the combinatorial formula:
  \(\text{Number of cables}=\frac{n(n-1)}{2}\)
  (For example, a network with 6 computers would require \(\frac{6 \times 5}{2} = 15\) separate cables.)

Why the other options require fewer cables

• Star topology: Requires exactly \(n\) cables (one cable running from each device directly to the central hub or switch).
• Bus topology: Requires just one continuous main backbone cable, with short drop lines connecting each node to it.
• Ring topology: Requires exactly \(n\) cables to close the circular loop connecting each device sequentially to its neighbors.

Solution :
505820260322101448 Correct Answer : It allows simultaneous transmission and reception

Description -

The correct answer is It allows simultaneous transmission and reception.

Why full-duplex is more efficient

• It allows simultaneous transmission and reception: In a full-duplex system, data can travel in both directions at the exact same time. Think of it like a modern two-way telephone call where both people can talk and listen simultaneously. Because devices do not have to wait for the other side to finish sending data before they can transmit, it completely eliminates idle waiting time and effectively doubles the network's potential throughput compared to half-duplex.

Why the other options are incorrect

• It uses less bandwidth: Full-duplex typically requires separate channels or media management that may consume equal or more bandwidth to handle simultaneous two-way traffic.
• It eliminates the need for communication: Communication is the entire purpose of the network.
• It requires only one device: All networking setups require at least two devices to communicate.

(Note: Half-duplex is like a walkie-talkie conversation, where only one person can speak at a time while the other listens, making it much slower and less efficient.)

Solution :
408020260322101401 Correct Answer : Radio broadcasting

Description -

The correct answer is Radio broadcasting.

Why Radio broadcasting matches this description

• Radio broadcasting: Simplex is a data transmission mode where communication is strictly unidirectional (one-way). The sender can only transmit data, and the receiver can only receive it; there is no way for the receiver to send feedback along the same path. In a radio broadcast, the radio station transmits the audio signal into the air, and your car radio plays it. You cannot speak back to the radio station through your radio device.

Why the other options are incorrect

• Telephone conversation: This is an example of Full-Duplex mode, as both parties can speak and listen at the exact same time.
• Walkie-talkie: This is an example of Half-Duplex mode, where communication goes both ways, but only one person can speak at a time.
• Video conferencing: This is an example of Full-Duplex mode, allowing all participants to transmit audio and video simultaneously.

Solution :
783320260322101306 Correct Answer : Half-Duplex

Description -

The correct answer is Half-Duplex.

Why Half-Duplex matches this description

• Half-Duplex: In this mode, communication is two-way, but only one direction at a time. Because the two devices cannot transmit simultaneously, the entire available bandwidth of the channel is allocated to whichever device is currently sending data. Once that transmission finishes, the direction can reverse, and the other device can use the full bandwidth to reply. A walkie-talkie is the classic real-world analogy.

Why the other options are incorrect

• Simplex: Communication is strictly one-way (unidirectional) at all times (like a TV broadcast). It does not allow two-way communication.
• Full-Duplex: Allows simultaneous two-way communication. The bandwidth is either split into two separate paths or managed so that both transmission and reception occur at the exact same time, rather than waiting for turns.
• Serial: This describes a data transmission method (sending data bit-by-bit sequentially over a single wire) rather than a directional transmission mode.

Solution :
987520260322101227 Correct Answer : Data flows in both directions simultaneously

Description -

The correct answer is Data flows in both directions simultaneously.

Why this option correctly describes full-duplex

• Data flows in both directions simultaneously: In full-duplex communication, the transmission medium allows for two-way communication where devices can send and receive data at the exact same time. There is no need to wait for the other device to finish transmitting, which maximizes network efficiency and eliminates idle waiting times.

Why the other options are incorrect

• Data flows only in one direction: This describes Simplex communication (e.g., traditional television or radio broadcasts).
• Data flows in both directions, but alternately:

This describes Half-Duplex communication (e.g., walkie-talkies), where devices must take turns transmitting.

• Data cannot be received: Incorrect, as full-duplex requires devices to actively receive data while transmitting.

Solution :
598620260322101122 Correct Answer : Half-Duplex

Description -

The correct answer is Half-Duplex.

Explanation

• Half-Duplex: In this mode, data transmission is bidirectional (both devices can send and receive), but only one device can transmit at a time. A classic example is a walkie-talkie.
• Simplex: Data travels in one direction only (unidirectional). An example is a television broadcast or keyboard.
• Full-Duplex: Data flows in both directions simultaneously. An example is a telephone call.

Solution :
862620260322101016 Correct Answer : It supports both half-duplex and full-duplex modes

Description -

The correct answer is It supports both half-duplex and full-duplex modes.

Explanation

• It supports both half-duplex and full-duplex modes: Fast Ethernet (100 Mbps) was designed to support both modes. Half-duplex mode uses the traditional CSMA/CD algorithm for shared media (like legacy hubs), while full-duplex mode disables CSMA/CD for point-to-point switched connections.
• It replaces CSMA/CD completely: While CSMA/CD is bypassed in full-duplex mode, Fast Ethernet still includes and supports the CSMA/CD protocol when operating in half-duplex mode.
• It only works in half-duplex mode: It fully supports full-duplex communications.
• It uses only fiber optic cables: Fast Ethernet works over both fiber optic cables (such as 100BASE-FX) and standard twisted-pair copper cables (such as 100BASE-TX).

Solution :
243920260322100931 Correct Answer : 4B/5B with MLT-3

Description -

The correct answer is 4B/5B with MLT-3.

Explanation

• 4B/5B with MLT-3: Fast Ethernet over copper wires (100BASE-TX) handles data in a two-stage encoding pipeline. First, the data passes through a block coding stage where 4-bit chunks are converted into 5-bit symbols (4B/5B) to ensure enough signal transitions for clock recovery. Then, to keep the frequency low enough for Category 5 copper cables, it uses MLT-3 (Multi-Level Transmit 3), which cycles through three voltage levels (-1, 0, +1).
• Manchester Encoding: Used in older, standard 10BASE-T Ethernet networks. It requires too much bandwidth for Fast Ethernet speeds.
• 8B/10B Encoding: Primarily used in Gigabit Ethernet (1000BASE-X) over fiber optics and high-speed serial links.
• NRZ only: Too inefficient on its own for this standard because long sequences of consecutive 0s or 1s cause clock drift and baseline wander.

Solution :
720260322100838 Correct Answer : 100 meters

Description -

The correct answer is 100 meters.

Explanation

• 100 meters: The official IEEE 800.3 standard restricts the maximum cable segment length for copper twisted-pair implementations like 100BASE-TX (and 10BASE-T/1000BASE-T) to 100 meters (approx. 328 feet). This limit ensures signal integrity and prevents timing issues caused by attenuation and propagation delay.
• 50 meters: Some high-speed standards or low-grade cables have lower limits, but it is not the standard segment max for 100BASE-TX.
• 500 meters: This is the maximum segment length for historical 10BASE5 thick coaxial cables ("Thicknet").
• 2 kilometers: This distance is achievable using fiber optic Fast Ethernet standards (like 100BASE-FX) in multi-mode configurations, not twisted-pair copper.

Solution :
559420260322100754 Correct Answer : 100BASE-TX

Description -

The correct answer is 100BASE-TX.

Explanation

• 100BASE-TX: This standard operates over two pairs of Category 5 (or higher) unshielded twisted-pair (UTP) cable. One pair is used for transmitting data and the other is used for receiving data, which allows it to support full-duplex communication (simultaneous two-way transmission).
• 100BASE-T4: This older standard requires four pairs of lower-grade Category 3 (or higher) UTP cable and operates exclusively in half-duplex mode because it bundles pairs together to achieve 100 Mbps.
• 100BASE-T2: This standard was designed to run over two pairs of Category 3 cable using advanced digital signal processing to support full-duplex, but it was rarely commercialised or deployed.
• 100BASE-FX: While this standard supports full-duplex communication, it runs over two strands of fiber optic cable, not copper twisted-pair.

Solution :
645520260322100701 Correct Answer : 100 Mbps

Description -

The correct answer is 100 Mbps.

Explanation

• 100 Mbps: The "100" in 100BASE-X (and other Fast Ethernet variations like 100BASE-TX or 100BASE-FX) directly represents its nominal, maximum theoretical data rate of 100 Megabits per second.
• 10 Mbps: This is the data rate of legacy, standard Ethernet (such as 10BASE-T).
• 1 Gbps: This is the data rate of Gigabit Ethernet (such as 1000BASE-T).
• 10 Gbps: This is the data rate of 10 Gigabit Ethernet (such as 10GBASE-T).

The naming convention follows a standard structure: [Data Rate in Mbps] + [Signalling Method (BASEband)] + [Medium/Encoding identifier (X)]. Therefore, Fast Ethernet is fundamentally defined by its 100 Mbps throughput speed.