Section 2: Network Fundamentals

Question 1

What is the primary difference between the Client-Server and Peer-to-Peer network models?

Answer 1

The Client-Server model is a centralized architecture where dedicated servers provide resources, while the Peer-to-Peer model is decentralized, with all computers sharing resources directly with each other.

Question 2

Why is the Client-Server model more scalable than the Peer-to-Peer model?

Answer 2

The Client-Server model is more scalable because its centralized nature makes it easy to add more clients and expand server capacity, whereas the P2P model becomes inefficient and difficult to manage as the network grows.

Question 3

What are the main drawbacks of the Client-Server model?

Answer 3

The main drawbacks are a higher initial cost for dedicated hardware and software, and the need for specialized IT staff to manage the servers.

Question 4

In which scenario would a Peer-to-Peer network be a suitable choice?

Answer 4

A Peer-to-Peer network is suitable for very small, low-cost networks, such as a home office with a few computers, where dedicated server hardware is not feasible.

Question 5

How does administration and backup differ between the Client-Server and Peer-to-Peer models?

Answer 5

In the Client-Server model, administration and backup are centralized and easier to manage on the server. In the P2P model, administration and backup are decentralized and difficult because data is located on many different machines.

Question 6

List the five main types of networks based on geography, from smallest to largest.

Answer 6

Personal Area Network (PAN), Local Area Network (LAN), Campus Area Network (CAN), Metropolitan Area Network (MAN), and Wide Area Network (WAN).

Question 7

What is the typical maximum distance for a single copper-based Ethernet segment in a LAN?

Answer 7

The typical maximum distance is 100 meters (or about 300 feet).

Question 8

Which IEEE standard defines Ethernet, and which defines Wi-Fi?

Answer 8

IEEE 802.3 defines Ethernet, and IEEE 802.11 defines Wi-Fi.

Question 9

What technology is defined by the IEEE 802.3 standard?

Answer 9

Ethernet.

Question 10

What technology is defined by the IEEE 802.11 standard?

Answer 10

Wi-Fi.

Question 11

What is the key difference between a Campus Area Network (CAN) and a Metropolitan Area Network (MAN)?

Answer 11

A CAN connects LANs in a limited area like a business park or college campus, while a MAN connects locations scattered across an entire city, covering a much larger area (up to 25 miles).

Question 12

What is the world’s largest example of a Wide Area Network (WAN)?

Answer 12

The Internet.

Question 13

What are some examples of technologies used to create a Personal Area Network (PAN)?

Answer 13

Bluetooth and USB are common technologies used for PANs.

Question 14

What does PAN stand for?

Answer 14

Personal Area Network.

Question 15

What does LAN stand for?

Answer 15

Local Area Network.

Question 16

What does CAN stand for?

Answer 16

Campus Area Network.

Question 17

What does MAN stand for?

Answer 17

Metropolitan Area Network.

Question 18

What does WAN stand for?

Answer 18

Wide Area Network.

Question 19

What is the primary difference between a hub and a switch?

Answer 19

A hub (Layer 1) broadcasts all traffic to every port, while a switch (Layer 2) intelligently forwards traffic only to the specific port of the intended recipient based on its MAC address.

Question 20

At which layer of the OSI model does a router operate, and what type of address does it use for forwarding decisions?

Answer 20

A router operates at Layer 3 (the Network Layer) and uses IP addresses to make its forwarding decisions.

Question 21

What is the function of a load balancer?

Answer 21

A load balancer distributes incoming network or application traffic across multiple servers to increase efficiency, capacity, and reliability, preventing any single server from becoming a bottleneck.

Question 22

Differentiate between an Intrusion Detection System (IDS) and an Intrusion Prevention System (IPS).

Answer 22

An IDS is a passive system that detects threats and alerts an administrator. An IPS is an active system that can both detect threats and take action to prevent them, such as by blocking malicious traffic.

Question 23

What is the difference between Network Attached Storage (NAS) and a Storage Area Network (SAN)?

Answer 23

A NAS is a file-level storage device providing data access to clients on a network. A SAN is a high-speed, block-level network that makes storage devices like disk arrays appear as locally attached drives to servers.

Question 24

When would you use a proxy server?

Answer 24

You would use a proxy server to act as an intermediary to the internet for purposes like web filtering, caching web content to improve performance, or hiding a user’s real IP address for privacy.

Question 25

What is the fundamental difference between a physical and a logical network topology?

Answer 25

A physical topology shows the actual physical layout and cabling of network devices, while a logical topology illustrates how data flows through the network, regardless of the devices' physical locations.

Question 26

Which type of topology would you use to find the physical location of a network switch in an office building?

Answer 26

A physical topology, as it is often drawn over a floor plan to show the real-world location of devices and cables.

Question 27

Which type of topology would be more useful for troubleshooting an IP routing issue?

Answer 27

A logical topology, because it focuses on the data flow, IP addressing schemes, and routing paths between different network segments.

Question 28

What is the most common wired network topology in modern LANs?

Answer 28

The star topology.

Question 29

What is the primary advantage of a mesh topology?

Answer 29

Its primary advantage is high redundancy and reliability, as there are multiple point-to-point connections between devices, providing many alternative paths for data.

Question 30

What is the central point of failure in a star topology? What about a bus topology?

Answer 30

In a star topology, the central connection point (the switch or hub) is the single point of failure. In a bus topology, the single central cable (the backbone) is the single point of failure.

Question 31

How does a hub-and-spoke topology differ from a standard star topology in terms of its common use case?

Answer 31

While both are centralized, a hub-and-spoke topology is typically used in WANs to connect multiple remote sites (spokes) to a central location (hub) to save on costs, whereas a star topology is most common in LANs.

Question 32

If you have 6 nodes, how many connections are required for a full-mesh topology?

Answer 32

15 connections. The formula is n(n-1)/2, so 6(5)/2 = 15.

Question 33

What is the most common type of wireless network topology?

Answer 33

Infrastructure mode, where devices connect through a central wireless access point.

Question 34

What is the primary difference between Infrastructure mode and Ad Hoc mode?

Answer 34

Infrastructure mode is centralized and uses a wireless access point to connect clients to a network. Ad Hoc mode is decentralized (peer-to-peer) and allows devices to connect directly to each other without an access point.

Question 35

What is a key characteristic of a wireless mesh network that makes it suitable for disaster recovery?

Answer 35

Its ability to provide redundant, reliable, and self-healing connections by combining multiple radio technologies (Wi-Fi, cellular, satellite) and allowing nodes to find alternative paths if one fails.

Question 36

Does Ad Hoc mode require a wireless access point?

Answer 36

No, Ad Hoc mode does not use routers or access points; devices connect directly to one another.

Question 37

In Infrastructure mode, what device connects wireless clients to the wired network?

Answer 37

A Wireless Access Point (WAP or AP).

Question 38

What are the three layers of the traditional hierarchical network model?

Answer 38

The Core layer, the Distribution (or Aggregation) layer, and the Access (or Edge) layer.

Question 39

In a three-tier hierarchy, which layer is responsible for connecting end-user devices to the network?

Answer 39

The Access layer (or Edge layer).

Question 40

What is the primary purpose of a spine-and-leaf architecture?

Answer 40

To optimize server-to-server (East-West) traffic within a data center, providing high bandwidth and low, predictable latency.

Question 41

Define 'North-South' traffic and 'East-West' traffic in the context of a data center.

Answer 41

North-South traffic is traffic that enters (southbound) or leaves (northbound) the data center. East-West traffic is data flow that moves between devices within the data center.

Question 42

In a spine-and-leaf architecture, what is the maximum number of hops between any two servers in the data center?

Answer 42

Two hops (from the source server's leaf switch, to a spine switch, to the destination server's leaf switch).

Question 43

When would a collapsed core architecture be a more suitable choice than a three-tier model?

Answer 43

A collapsed core architecture is suitable for smaller or medium-sized data centers where the cost and complexity of a separate core and distribution layer are not required.