Network Basics

Question 1

Computer Networks

Answer 1

Networks are used to make connections between machines.

Question 2

Purpose of Networks

Answer 2

To make connections between machines.

Question 3

Network Traffic Examples

Answer 3

• File sharing
• Video chatting
• Surfing the web
• Social Media
• Streaming Video
• E - mail
• Messaging
• VoIP

Question 4

Network components

Answer 4

• Client
• Server
• Hub
• Wireless Access Point
• Switch
• Router
• Media
• WAN Link

Question 5

Client

Answer 5

Device end-user use to access the network.

Can be any device that connects to the network.

Question 6

Server

Answer 6

Provides resources to the rest of the network.
Different servers provide different functions.
There can be dedicated server hardware/software.

Question 7

Converged Networks

Answer 7

Combines multiple types of traffic like data, video, and voice in a single network.

Question 8

Hub

Answer 8

• Can be interconnected to provide more ports, but leads to increased
  network errors
• Receives information in one port and rebroadcasts it out all the other
  ports

Question 9

Wireless Access Point (WAP)

Answer 9

• Device that allows wireless devices to connect into a wired network
• Commonly used in the home, small business, and even some large enterprise
  networks
• Acts as a wireless hub

Question 10

Switch

Answer 10

• Connects networked devices such as clients and servers (like a hub)
• Switches learn what devices are on which switch ports
• Switches only forward traffic received from a port to the destination port
  based on the device’s MAC address
• Provides more security and efficiently uses available bandwidth

Question 11

Router

Answer 11

• Connect two different networks together
• Intelligently forwards traffic to and from a network based on its logical
  address
• Most modern routers use Internet Protocol (IP) address to determine
  routing of traffic

Question 12

Media

Answer 12

• Connect two devices or a device to a port
• Made from copper cable, fiber optic cable, or radiofrequency waves
  (WiFi)
• Each type has strengths and limitations, such as its available bandwidth,
  capacity, distance that can be covered, and cost to install and

Question 13

Wide Area Network (WAN) Link

Answer 13

• Physically connects networks together
• Numerous WAN links are available: leased lines, DSL, Cable, Fiber Optic, Satellite, Cellular, Microwave,…
• Connects internal network to external networks, such as a SOHO network to the internet

Question 14

Client/Server Model

Answer 14

• Uses a dedicated server to provide access to files, scanners, printers, and
  other resources
• Administration and backup are easier since resources are located on a
  few key servers

Question 15

Client /Server Benefits

Answer 15

• Centralized administration
• Easier management
• Better scalability

Question 16

Client/Server Drawbacks

Answer 16

• Higher cost
• Requires dedicated resources
• Requires network operating system

Question 17

Peer-to-Peer Model

Answer 17

• Peers (PCs) share resources (files/printers) with each other directly
• Administration and backup are more difficult e since resources are located
  on many PCs which adds to the administrative burden- Higher cost

Question 18

Peer-to-Peer Benefits

Answer 18

• Lower cost
• No dedicated resources required
• No specialized operating system required

Question 19

Peer-to-Peer Drawbacks

Answer 19

• Decentralized management
• Inefficient for large networks
• Poor scalability

Question 20

Personal Area Network (PAN)

Answer 20

• A small type of wired or wireless network
• Covers the least amount of area (few meters)
• Examples: Bluetooth, USB hard drive, firewire

Question 21

Local Area Network (LAN)

Answer 21

• Connects components in a limited distance
• Limited to short distances, 100 meters with CAT5
• Consist of Ethernet (IEEE 802.3) or WiFi networks (IEEE 802.11)

Question 22

Campus Area Network (CAN)

Answer 22

• Connects building-centric LANs across a university, industrial park, or business park
• Covers many square miles and buildings
• Example: College campus, Business Parks, Military base

Question 23

Metropolitan Area Network (MAN)

Answer 23

• Connects scattered locations across a city
• Larger than CAN, but smaller than a WAN
• Covers up to a 25-mile radius
• Examples: City department (like police), Community College with multiple Campuses

Question 24

Wide Area Network (WAN)

Answer 24

• Connects geographically disparate internal networks
• Consist of leased lines or Virtual Private Networks tunneled over the Internet
• Covers distances around the country or around the world
• Examples: Internet, Privat corporate networks

Question 25

Bus Topology

Answer 25

• Uses a cable running through the area that required network connectivity
• “taps” into the cable using either a T connector or vampire Tap
• not commonly used, devices on cable form single collision domain

Question 26

Ring Topology

Answer 26

• Uses a cable running in a circular loop
• each device connects to the ring, but data travels in a singular direction
• FDDI (Fiber networks) used two counter-rotating rings for redundancy
• token ring network waits for a turn to communicate on the ring

Question 27

Star Topology

Answer 27

• Most popular Physical LAN topology
• Connects to a single point
• If the central device fails, the entire network fails

Question 28

Hub-and-Spoke Topology

Answer 28

• Used to connecting multiple sites
• Similar to Star, but uses WAN links
• not redundant, if central office fails, the whole network can fail

Question 29

Full-Mesh Topology

Answer 29

• Most redundant topology
• Every node connects to every other node
• Optimal routing is available
• Expensive to maintain and operate
• Number of connections: x=n(n-1) / 2