Network Fundamentals

Question 1

What are clients in a network?

Answer 1

Devices that users use to access the network (e.g., workstations, laptops, tablets)

Clients are the end-user devices that interact with network resources.

Question 2

What is the role of servers in a network?

Answer 2

Provide resources to the network (e.g., email servers, file servers)

Servers are crucial for resource management and sharing within a network.

Question 3

What is a hub?

Answer 3

Older technology connecting devices but not commonly used due to limitations

Hubs broadcast data to all connected devices, leading to inefficiencies.

Question 4

What is the function of switches in a network?

Answer 4

Smarter hubs that ensure security and efficient bandwidth utilization

Switches direct data to specific devices rather than broadcasting it.

Question 5

What do Wireless Access Points (WAPs) do?

Answer 5

Enable wireless devices to connect to a wired network using radio frequency waves

WAPs are essential for expanding network access to mobile devices.

Question 6

What is the purpose of routers?

Answer 6

Connect different networks, make intelligent forwarding decisions based on IP addresses

Routers manage traffic between different networks.

Question 7

What is the function of firewalls in a network?

Answer 7

Security barrier between internal network and the internet, monitor and control traffic

Firewalls are critical for protecting networks from unauthorized access.

Question 8

What do load balancers do?

Answer 8

Distribute network/application traffic across servers, preventing bottlenecks

Load balancers enhance performance and reliability.

Question 9

What is the role of proxy servers?

Answer 9

Act as intermediaries between user devices and the internet, enhancing security and privacy

Proxy servers can also cache data to improve speed.

Question 10

What do Intrusion Detection Systems (IDS) do?

Answer 10

Detect unauthorized access or anomalies

IDS are critical for monitoring network security.

Question 11

What is the function of Intrusion Prevention Systems (IPS)?

Answer 11

Detect and take action to prevent intrusion

IPS actively block threats rather than just detecting them.

Question 12

What do controllers manage in software-defined networking (SDN)?

Answer 12

Manage flow control, offering flexibility and efficiency

Controllers are central to the SDN architecture.

Question 13

What are Network-attached Storage (NAS) devices?

Answer 13

Dedicated file storage systems providing data access to authorized clients

NAS devices facilitate centralized file storage and access.

Question 14

What are Storage Area Networks (SANs)?

Answer 14

High-speed networks for consolidated block-level data storage, enhancing accessibility

SANs are designed for high-performance data storage and retrieval.

Question 15

What is the definition of media in networking?

Answer 15

Physical materials for data transmission (e.g., copper cables, fiber optic cables)

Media are the mediums through which data travels in a network.

Question 16

What are Wide Area Network (WAN) links used for?

Answer 16

Connect networks over large areas (e.g., between cities), essential for global connectivity

WAN links enable communication across extensive geographical distances.

Question 17

What is the client/server model?

Answer 17

Utilizes a dedicated server for centralized access to files, scanners, printers, and resources

This model simplifies network management and backup.

Leading model in business networks

Question 18

What are the benefits of the client/server model?

Answer 18

• Centralized administration
• Easier management
• Better scalability

Centralization allows for streamlined operations.

Question 19

What are the drawbacks of the client/server model?

Answer 19

• Higher cost
• Requires dedicated hardware and specialized skillset

Initial setup and maintenance can be costly.

Question 20

What characterizes the peer-to-peer model?

Answer 20

Direct sharing of resources among peers (laptops, desktops)

This model is often used for small networks.

Does not differentiate between devices providing services and devices requesting services

Question 21

What are the drawbacks of the peer-to-peer model?

Answer 21

• Redundancy
• Complex management
• Scalability issues

These issues make it less suitable for larger networks.

Question 22

What is a Personal Area Network (PAN)?

Answer 22

Smallest network type, covering about 10 feet or less

Examples include Bluetooth and USB connections.

Question 23

What defines a Local Area Network (LAN)?

Answer 23

Common in office buildings, limited distance (up to 100 meters)

LANs can utilize WiFi or Ethernet for connectivity.

Question 24

What is a Campus Area Network (CAN)?

Answer 24

Building-centric LAN that spans numerous buildings in an area

Common examples include college campuses and business parks.

Question 25

What is a Metropolitan Area Network (MAN)?

Answer 25

Connects locations across the entire city, larger than CAN (up to 25 miles) ## Footnote MANs are used to connect various city locations.

Question 26

What is a Wide Area Network (WAN)?

Answer 26

Connects geographically disparate internal networks, covering large areas ## Footnote WANs can consist of leased lines or VPNs.

Question 27

What are the key standards for network geography?

Answer 27

* PAN – Bluetooth, USB * LAN – IEEE 802.3 (Ethernet) * CAN – connects multiple LANs * MAN – spans an entire city * WAN – encompasses large geographic areas ## Footnote These standards guide the design and implementation of networks.

Question 28

What is network topology?

Answer 28

Refers to the arrangement of elements in a computer network, including links, nodes, clients, and servers ## Footnote Topology affects network performance and management.

Question 29

What is physical topology?

Answer 29

Describes physical cabling and device connections, representing real-world layout using floorplans ## Footnote Physical topology is used for practical network design.

Question 30

What is logical topology?

Answer 30

Describes how data flows in the network, focusing on logical connections rather than physical placement Think of data flow ## Footnote Logical topology helps in understanding data transmission paths.

Question 31

What is point-to-point topology?

Answer 31

Direct connection between two devices, simple and reliable for small-scale connections ## Footnote This topology is not scalable.

Question 32

What characterizes ring topology?

Answer 32

Used in WAN connections for remote offices, features a circular data path ## Footnote Unidirectional flow can prevent collisions but creates a single point of failure.

Question 33

What is bus topology?

Answer 33

All devices connected to a central cable (bus), easy to install but prone to failures if the main cable fails ## Footnote This older technology is less common in modern networks.

Question 34

What defines star topology?

Answer 34

Each node connected to a central point (network switch), robust but dependent on the central point's functionality ## Footnote Common in home networks.

Question 35

What is hub-and-spoke topology?

Answer 35

Variation of star topology with a central hub connected to multiple spokes, used in larger networks ## Footnote This topology is less expensive for larger setups. Airplane example

Question 36

What is mesh topology?

Answer 36

Point-to-point connections between every device for FULL REDUNDANCY, can be full or partial mesh Think of a web ## Footnote Provides robustness but can be complex and costly. Circle or several cables connecting each device- think of a net

Question 37

What is infrastructure mode in wireless networking?

Answer 37

Centralized wireless network with a wireless access point, similar to star topology ## Footnote Commonly used in home networks.

Question 38

What is ad hoc mode in wireless networking?

Answer 38

Decentralized wireless network where devices connect directly without routers or access points ## Footnote Operates like a peer-to-peer network ■ No routers or access points ● Devices connect directly This mode allows for dynamic joining and leaving of devices.

Question 39

What is wireless mesh networking?

Answer 39

Unique interconnection of different nodes, devices, and radios for expansion and redundancy ## Footnote Post-disaster scenarios ● Humanitarian assistance missions ● Combining microwave, satellite, cellular, and WiFi for reliable and redundant networks In harsh environments.

Question 40

What is the three-tiered hierarchy in datacenters?

Answer 40

* Core Layer * Distribution/Aggregation Layer * Access/Edge Layer CDA ## Footnote Each layer has distinct roles for performance, management, and scalability.

Question 41

What is the collapsed core architecture?

Answer 41

Network architecture where the core and distribution layers are merged into a single layer ## Footnote Suitable for medium to small datacenters.

Question 42

What is spine and leaf architecture?

Answer 42

Two-layer switching architecture used specifically within datacenters, focusing on communication within server farms Leaf ○ Consists of all the access switches that will aggregate traffic from the different servers and then connect directly into the spine layer ● Spine ○ Contains switches that interconnect all the leaf layer switches into a full-mesh topology ## Footnote Enhances speed and reduces latency.

Question 43

What is north-south traffic in datacenters?

Answer 43

Traffic that enters (Southbound) or leaves (Northbound) the data center from a system outside ## Footnote This traffic is crucial for external communications.

Question 44

What is east-west traffic in datacenters?

Answer 44

Data flow within a datacenter, prevalent with SDN, virtualization, and converged networks ## Footnote This type of traffic is critical for server-to-server communication.

Question 45

802.11

Answer 45

WIFI

Question 46

802.3

Answer 46

ETHERNET