3.1 - Networks

Question 1

3.1.1. What is a network?

Answer 1

A group of nodes connected via a transmission medium used to share resources

Question 2

3.1.1 What is a LAN?

Answer 2

• it is a local area network, that acts over a small geographic area, and devices are private infrastructure
• they are switched based using MAC addresses

Question 3

3.1.1 What is a WLAN

Answer 3

• a wireless LAN
• it uses radiowaves

Question 4

3.1.1 What is a VLAN

Answer 4

• a virtual LAN
• a software based partition of a physical LAN

Question 5

3.1.1 - What is a WAN

Answer 5

• a wide area network that acts over a large geographical area, connecting multiple LANs
• they are router based using IP addresses

Question 6

3.1.1 What is a PAN?

Answer 6

• a Personal Area Network that usually uses bluetooth

Question 7

3.1.1 What is a SAN?

Answer 7

• a Storage Area Network using shared server base file management
• it gives shared access to a storage area

Question 8

3.1.1 - What is a Intranet

Answer 8

• a restricted access private network
• resources on this can only be accessed via the private LAN
• intranets are very secure

Question 9

3.1.1 - What is an extranet?

Answer 9

• it provides remote access to most intranet services and apps, using authentication as a security method

Question 10

3.1.1 - What is a VPN?

Answer 10

• a Virtual Private Network that extends private networks across a public network

Question 11

3.1.2 - What is a Newtork Standard

Answer 11

• they are an an agreed way of doing things, ensuring interoperability between devices

Question 12

3.1.2 - Why are network standards important?

Answer 12

• describes accurately how information is transmitted -> enables reliable communication between devices
• without standards communication would be impossible

Question 13

3.1.4 - What is encryption?

Answer 13

• converts plaintext into cipher text, and requires a key to be read protecting the data

Question 14

3.1.4 What is Tunneling?

Answer 14

• it is a secure pathway through a public network
• the tunnel js created using protocols

Question 15

3.1.5 - Benefits of Teleworking via VPNs

Answer 15

• increased productivity
• reduced chance of resigning -> happier employees
• less stress
• smaller environmental impact

Question 16

3.1.5 - Disadvantages of Teleworking via VPNs

Answer 16

• needs a professional with detailed understanding of the work to support the employees
• not all VPNs are compatible with products
  -blurring boundaries for a work-life balance

Question 17

3.1.3 - Why do we need layers?

Answer 17

• self contained (errors in one layer won’t affect the other)
• similar protocols are grouped into a layer
• software developers can work on one layer without affecting the others

Question 18

3.1.3 - OSI name of all 7 layers

Answer 18

application
presentation
session
transport
network
data link
physical

Question 19

3.1. 3 - What layers are within TCP/IP stack? And their purpose.

Answer 19

(ATNL)
- Application: presents and prepares data for transmission
- Transport: splits data into packets
- Network: IP addresses are added (sender + receiver)
- Link: MAC addresses are added and data is transmitted (packet switching)

Question 20

3.1.6 - What is a protocol?

Answer 20

A set of rules for data transmission over a network

Question 21

3.1.7 - 3 purposes of protocols

Answer 21

• to allow communication -> without protocols, different devices would use different rules for transmission
• manage flow control -> rate at which sender is transmitting data is in proportion to receiver’s receiving capabilities
• perform error checking -> ensures data is accurate and consistent

Question 22

3.1.8 - What are some primary factors that affect network speed?

Answer 22

• number of users
• cable quality
• type of connection

Question 23

3.1.8 - What are some secondary factors that affect network speed?

Answer 23

• traffic
• time of day
• distance
• infrastructure

Question 24

3.1.9 - What can we use compression for?

Answer 24

• backups
• file transfer
• media transfer
• encryption and protection

Question 25

3.1.9 - Differences between Lossy and Lossless Compression

Answer 25

• Lossy makes files much smaller, but data is lost in decompression (quality is not maintained)
• Lossless creates a larger compressed files but all data is restored exactly

Question 26

3.1.9 - Why use compression?

Answer 26

• network has a limited bandwidth it can transmit
• decreases transmission times

Question 27

3.1.10 - Characteristics of transmission media

Answer 27

Radio waves: Least secure, susceptible to interference, free, slow

UTP (unshielded twisted pair): Not very secure, susceptible to interference, free, not fast

Fibre- Optic: Most secure, fragile, most expensive, fastest