networks

Question 1

Define computer network

Answer 1

A computer network is defined as the interconnection of two or more computers/devices. It is done to enable the computers to communicate and share files, other hardware devices like printers, and share an Internet connection.

Question 2

Advantages of a wireless home network (5)

Answer 2

Sharing of resources : a network allows users to share many hardware devices such as printers, modems (to get on to the Internet) etc
File sharing : Data can be easily shared between different users, or accessed remotely if it is being kept on other connected devices.
Communication : People on a network can communicate easily through the network and Internet.
Reduce costs : Sharing of resources also helps to reduce costs.
Flexibility : to move around the house within a certain distance.

Question 3

Disadvantages of a wireless home network

Answer 3

Set up of a network maybe difficult for people who are unfamiliar with the set up
Security – over a wireless network is more vulnerable
Interference over a wireless network is greater than a wired network.
Capabilities of hardware may slow the network down
Limited to the amount of traffic or the amount of devices that can use the network at any one time

Question 4

What is a PAN (definition, usage)

Answer 4

Personal area network is a personal, short distance area wireless network for interconnecting devices centred around an individual person’s workspace.
It is used for data transmission amongst devices such as computers, telephones, tablets.
Wireless networking and mobile computing devices such as PCs, PDAs, peripherals, cell phones and consumer electronics.

Question 5

What is a LAN (definition, private/public, advantages)

Answer 5

LAN is a network which is designed to operate over a small physical area such as an office, factory or a group of buildings.
LAN’s are easy to design and troubleshoot
Exchange of information and sharing of resources becomes easy because of LAN.
In LAN all machines are connected to a single cable.
It is usually a privately owned network.
Advantages include high data transfer rates, low latency and easier administration due to the smaller coverage area

Question 6

What is a WAN (advantages, wired, wireless or both)

Answer 6

A wide area network is a network that connects networks across cities or countries.
Advantages include it enables communication between widely separated locations, facilitating the sharing of resources and data on a global scale. It relies on a combination of wired and wireless technologies.

Question 7

What is a stand-alone computer?

Answer 7

A “stand-alone computer” refers to a computer system that operates independently and is not connected to any network or other computing devices. It functions in isolation, meaning it does not share resources or data with other computers, and it does not rely on a network connection to perform its primary functions.

Question 8

what is a router

Answer 8

• Connects two networks together.
• This device will connect your network to the Internet
• It allows the two networks to ‘talk’ to one another

Question 9

what is a modem

Answer 9

• Short for Modulator - Demodulator.
• Connects to telephone line. Changes digital data into analogue and back to digital once it arrives at destination.

Question 10

what is a firewall

Answer 10

• Firewalls can be either a physical device or software based.
• It is a security system that monitors and controls the incoming and outgoing network traffic based on security rules.
  Only traffic that meets all security rules will be allowed in and out of the network

Question 11

what is a switch

Answer 11

• The main function of a switch is to connect network devices together.
• A switch receives messages from one device and sends it to only the intended device.
  The number of ports on a switch can vary, with businesses commonly using between 24 and 48 port switches.

Question 12

what is a work station

Answer 12

Commonly used for personal computing tasks, such as web browsing, email, document creation, and multimedia consumption. They provide a user-friendly interface for individuals to interact with digital content and software applications

Question 13

what is a server

Answer 13

• A computer or device on a network that manages network resources.
• Servers can be both physical and virtual. Bigger businesses will purchase servers with higher hardware capacity and can run multiple virtual servers on the one device.
• Generally, servers have one purpose each. For example, a print server to manage all the printing in a company, mail server to manage all emails and a file server to manage all of the documents within a company.

Question 14

what is a wireless access point (WAP)

Answer 14

• Connects to a network through the switch and ethernet cable
• Allows wireless devices to connect to the network through WiFi

Question 15

name 3 types of transmission media

Answer 15

twisted pair, coaxial cable, fibre optic cable

Question 16

describe the twisted pair cable

advantages + disadvantages

Answer 16

a simple type of cabling made up of two copper wires twisted around each other (this helps to stop interference)
this is used in our school network (the blue cables seen at the back of the computers).
It has a data transfer rate of up to Gbps
It is cheaper than other forms of wired media

pros:
- Cheap
- Most common network cable
- Transmit both audio and other multimedia data.

cons:
- Affected by electromagnetic interference & noise
- Limited bandwidth
- Low data transmission rate

Question 17

describe the coaxial cable

advantages + disadvantages

Answer 17

Has a central copper cable that transmits data
It is surrounded by a shield of copper braiding which protects the central cable for interference
Mainly found in factories and manufacturing plants where there is a lot of possible interference
Coaxial cable is more expensive than twisted pair.

pros:
- Supports high bandwidth
- Easy to install
- Less affected by noise

cons:
- Expensive for longer distances
- Needs to be grounded
- Have multiple layers - making it bulky

Question 18

describe the fibre optic cable

advantages + disadvantages

Answer 18

is made up of fine strands of glass that carry pulses of light.
The pulses of light carry the data being transferred.
More secure than copper cabling as any break in this cable can be detected.
It does not suffer from interference
Can transmit data at very high speeds up to 100 tbps
Commonly used to connect buildings together in a LAN
It is very expensive

pros:
- Longer distances
- Thinner and lighter than copper wires
- The error rate is low.

cons:
- Costs a lot
- Installation is more - expensive
- More fragile

Question 19

what does bandwidth refer to

Answer 19

the capacity at which a network can transmit data. a good wifi bandwith is at least 25 Mbps.

Question 20

what is a type of ethernet port

Answer 20

RJ-45

Question 21

describe two advantages of a dual band router

Answer 21

1. They can transfer internet data at faster speeds than traditional adapters.
2. They also operate on two different frequencies, which helps to reduce network congestion and interference, resulting in improved speed and performance.

Question 22

what does a DNS stand for and what does it do

Answer 22

Domain Name System is one of the fundamental components of the internet that makes it user-friendly by converting your URL address into an Internet Protocol address (IP address) so that a router can then find that address using a routing table. Without DNS, we would have to enter IP addresses into our web browser address bar to get to a website.

Question 23

what are two reasons someone would use a third-party DNS:

Answer 23

1. Phishing protection
2. Parental controls

Question 24

what function does a third party DNS service provide and name one reason not to use it

Answer 24

A third-party DNS service can offer faster speeds and additional features, but one reason not to use it is potential privacy concerns.

Question 25

where is the internet

Answer 25

the internet is located in 3 basic parts: - the last mile: connects homes + small businesses to internet - data centres: rooms full of servers that store user data and host online apps and content - backbone: consists of long-distance networks - mostly fibre optic cables - that carry data between data centres and consumers

Question 26

who created the internet and who runs it

Answer 26

Bob Taylor and no one runs it, its organised as a decentralised network of networks

Question 27

what is an IP address

Answer 27

Internet Protocol addresses are numbers that computers use to identify each other on the internet.

Question 28

how does wireless internet work

Answer 28

There are two basic types of wireless internet access: wifi and cellular. Wifi networks are relatively simple. Anyone can purchase wifi networking equipment in order to provide internet access in a home or business. Wifi networks use unlicensed spectrum: electromagnetic frequencies that are available for anyone to use without charge. Cellular networks are more centralized. They work by breaking up the service territory into cells. In the densest areas, cells can be as small as a single city block; in rural areas a cell can be miles across. Each cell has a tower at its centre providing services to devices there. When a device moves from one cell to another, the network automatically hands off the device from one tower to another, allowing the user to continue communicating without interruption.

Question 29

what is the cloud

Answer 29

By storing files on servers and delivering software over the internet, cloud computing provides users with a simpler, more reliable computing experience. Cloud computing allows consumers and businesses to treat computing as a utility, leaving the technical details to technology companies.

Question 30

what is a data packet

Answer 30

A packet is the basic unit of information transmitted over the internet. Splitting information up into small, digestible pieces allows the network’s capacity to be used more efficiently.

Question 31

what technology is used to secure web browsing

Answer 31

SSL, short for Secure Sockets Layer, is a family of encryption technologies that allows web users to protect the privacy of information they transmit over the internet.

Question 32

who decides what domain names exist and who gets them

Answer 32

The domain name system is administered by the Internet Corporation for Assigned Names and Numbers (ICANN)

Question 33

describe the features of bluetooth | (waves, speed, direct line?)

Answer 33

Radio waves 10m Distance, 2 megabits per second Does not need direct line of sight

Question 34

describe the features of infrared | (radiation, direct line of start, distance?)

Answer 34

infrared radiation Couple of meters Needs line of sight

Question 35

describe features of wifi | (waves, distance, direct line of sight?)

Answer 35

Microwaves Up to 100m Does not need line of sight

Question 36

what is the difference between the yellow lan ports and blue internet ports on a router

Answer 36

Yellow LAN ports connect devices within your local network, while the blue internet port connects to your modem for external internet access.

Question 37

what does SSID represent on a wireless network

Answer 37

SSID represents the network name of a wireless network that users see when they search for available networks.

Question 38

what advantage does using both 2.4 GHz and 5GHz frequencies provide

Answer 38

Using both 2.4GHz and 5GHz frequencies allows for better device compatibility (2.4GHz) and faster speeds with less interference (5GHz).

Question 39

what information does the DHCP clients list contain

Answer 39

The DHCP Clients List contains a list of devices currently connected to the network via DHCP, showing their IP addresses and MAC addresses. | Dynamic Host Configuration Protocol

Question 40

what does lease time refer to in the context of networking and DHCP

Answer 40

lease time refers to the duration a device can use an assigned IP address before it needs to renew the lease with the DHCP server.

Question 41

what do you think changing the range (start + end values) will have on the allocated IP addresses

Answer 41

Increasing the range (e.g., extending the End value) will allow for a larger pool of IP addresses to be allocated to connected devices, accommodating more devices on the network. Decreasing the range (e.g., reducing the End value) will limit the pool of available IP addresses, potentially causing IP address conflicts or preventing new devices from connecting to the network if the pool becomes exhausted.

Question 42

what do you think changing the lease time to 1 minutes will have on the connected devices

Answer 42

Devices will have very short-lived IP addresses, leading to frequent renewals and potential disruptions in network connectivity. This configuration may be useful in scenarios where you want strict control over IP address assignments or in environments with extremely dynamic device connections, such as a public Wi-Fi hotspot.

Question 43

explain the role a DHCP server has in a local network

Answer 43

* IP Address Assignment: The DHCP server assigns IP addresses dynamically to devices when they join the network, eliminating the need for manual IP configuration on each device. * Network Configuration: It provides additional configuration information, such as subnet masks, default gateways, DNS servers, and more, to ensure that devices can communicate effectively on the LAN. Lease Management: DHCP servers manage the lease duration of IP addresses, allowing for efficient allocation and recycling of addresses as devices join and leave the network.

Question 44

advantage of using a DHCP server over manually set IP addresses

Answer 44

* Automation: DHCP automates the IP address assignment process, reducing the administrative burden of manually configuring IP addresses on each device. * Efficiency: It efficiently manages IP address allocation and ensures optimal utilization of available addresses, reducing the likelihood of IP conflicts.

Question 45

difference between static IP and dynamic IP addresses

Answer 45

A static IP address doesn't change A dynamic IP address will grant IP addresses once connected to a network, can change over time.

Question 46

what is a firewall and explain how it helps protects the network

Answer 46

A firewall protects your network by ensuring no malware enters your network. A firewall is a network security device or software that monitors and controls incoming and outgoing network traffic based on predetermined security rules. It helps protect your network by blocking unauthorised access, filtering malicious data and preventing cyberattacks from reaching your device.

Question 47

what is the order in which you should draw a network diagram (router, internet, modem, firewall)

Answer 47

internet modem firewall router