08 Networking

Question 1

what is a computer network

Answer 1

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. Networks have their own operating system to control communication, handle conflicts and run smoothly

Question 2

Describe fibre optic cables

Answer 2

It uses special glass/plastic strands to transmit light pulses. The light is not susceptible to EMI, therefore reliably carry data for up to 50 kilometers.

Question 3

Describe satellites

Answer 3

wireless communication using radio waves/microwaves to communicate between Earth’s stations and orbiting satelites.

Question 4

Describe microwaves

Answer 4

It is a wireless transmission method requiring line-of-sight between sending and receiving dishes, capable of handling higher data rates, over short and long distances.

Question 5

Describe cellular

Answer 5

radio network distributed over land areas, each served by at least one fixed-location transceiver.

Question 6

Describe infrared

Answer 6

Short-ranged wireless transmission technology using light waves and it requires line of sight access.

Question 7

Describe bluetooth

Answer 7

It uses short-range radio waves to transmit data over distances for up to 10m. It connects mobile devices together.

Question 8

Define data rate

Answer 8

The speed at which data is transferred, measured in bits per second (bps)

Question 9

Define crosstalk

Answer 9

interference caused by signals in one wire affecting signals in adjacent wires.

Question 10

Define bandwidth

Answer 10

the range of frequencies available for transmitting data

Question 11

what is a network protocol

Answer 11

It is a set of rules followed by the network. They are made up of rules, procedures and formats that defines communication across a network.

Question 12

what is a network standard

Answer 12

It is an industry agreed upon standard for the rules that make up protocols. It is also a standard as there is an industry agreed upon a set of rules to use to communicate.

Question 13

What are the 7 layers of the OSI model

Answer 13

7. Application
8. Presentation
9. Session
10. Transport
11. Network
12. Data link
13. Physical

Question 14

What is HTTP protocols

Answer 14

It stands for Hypertext transfer protocol. It is a set of rules that a server has to follow when it comes to the transmission of files through the World Wide Web (WWW).

Question 15

What is HTTPS protocol

Answer 15

It stands for Hyper Text Transfer Protocol Secure. HTTPS is a combination of HTTP with SSL (Secure Socket Layer) or TLS (Transport Layer Security – newest security layer). It means all communications between your browser and the website are encrypted. HTTPS is often used to protect highly confidential online transactions like online banking and online shopping order forms. HTTPS mandatorily requires domain validations and certain certifications. Unless communication is encrypted, anyone intercepting the communication can easily read what is being communicated. So where security is needed, HTTPS is essential.

Question 16

What is a WAP protocol

Answer 16

It is an old standard used to access data over a mobile wireless system.
it can access all operating systems, on all mobile devices such as smartphones, tablets, laptops. It uses Wireless Markup Language (WML) delivers the content to the smaller display screens. Most modern mobile devices use HTTP protocol instead.

Question 17

What are some advantages of WAPs

Answer 17

• It simplifies the receipt of internet content to wireless devices
• it standardises the way that wireless/mobile devices, such as cellular telephones and radio transceivers, can be used for internet access, including email, the World Wide Web, newsgroups, and instant messaging
• it enhances wireless specification interoperability
• it is supported by all operating systems.

Question 18

define LAN networks

Answer 18

A local area network (LAN) connects computers and devices in a limited geographical area. Each computer or device on the network is a node. Often, the nodes are connected to the LAN through cables. A wireless LAN uses no physical wires; instead it uses wireless media, such a radio waves. Nodes on a wireless LAN must therefore have wireless capabilities. Usually a WLAN will connect with a wired LAN for access to its resources such as software, hardware and the Internet.

Question 19

what is a peer to peer network

Answer 19

It is a network that is simple and inexpensive. Each computer can share resources such as a printer, data or information located on any other computer on the network. Each computer stores files and software on its own storage devices. It is ideal for a very small business or home network users. Some OS include peer-to-peer networking utilities.

Question 19

what is a client server network

Answer 19

In a client-server network a server (host computer) controls access to the hardware and software on the network and provides a centralised storage area for programs, data and information. The other computers are called clients. Clients rely on the server for resources. Servers have more storage space and power. Dedicated servers perform a specific task. It costs a little more than peer-to-peer networks. It requires ongoing support to maintain the network.

Question 20

Define topology

Answer 20

It is the layout of a network. It depends on the type of information being shared, the volume of communications, and how devices need to store data.

Question 20

what is a bus topology

Answer 20

• It uses a central cable to which all network devices connect.
• All data is transmitted down the bus line from one device to another
• If the bus line fails, then the network cannot function.
• Cheap and easy to setup
• The central bus can be a bottle neck
• Central bus problems affect the whole network
• Can only really be used to create simple networks

Question 21

what is a ring topology

Answer 21

• Each node connects to exactly two other nodes, forming a single continuous pathway for signals through each node – this forming a ring.
• Data travels from node to node, with each node along the way handling every packet.
• No central point or bus so no bottlenecks.
• No need for a network server as routing is simple
• However, if one node goes down, it breaks the network.
• It is the slowest network.

Question 22

what is a mesh topology

Answer 22

• It uses a number of different connections between network devices.
• Devices may connect using a star topology via a switch, but may also be linked directly to each other in a ring, and also connected independently.
• Data can take any of several possible paths from source to destination.
• Because data can be transmitted from different devices simultaneously it can handle high levels of traffic, and is more tolerant of network issues than other topologies
• However, it is complicated and costly to setup.

Question 23

what is a wired star topology

Answer 23

- It has a central point, normally a switch - It has connections to that switch from outer points, usually computers is the most common topology for a network - The client computers send requests to a server via a switch. The server then will serve the requested resources back to the client computers. - Excellent performance overall - Easy to connect new devices - If a node goes down, its impacts are minimal - However, if the central node goes down, the whole network is affected - Expansion of network depends on capacity of central node.

Question 24

what are the two wireless topologies and describe them

Answer 24

Star: the star toplogy used by Wi-Fi resembles the wired star network. The access point takes the place of a switch because stations connect via the access point, rather than directly with each other. This method is more expensive, but permits better performance with regard to speed and is easier to manage. Point-to-point: Bluetooth products, and ad hoc Wi-Fi products use the point-to-point topology. These devices connect directly with each other and require no access point or hub like device to communicate with each other. It is cheaper than a wireless star network; however, it is best suited for temporary data sharing devices and is much slower.

Question 25

what is a network interface card (NIC)

Answer 25

It enables a device, such as a computer or printer, to connect to a network, whether it is wired or wireless. It links a computer to a resource (printer, scanner etc.) It also coordinates the transmission and receipt of data, instructions and information to and from the computer containing the network card.

Question 26

what is a wireless access point (WAP)

Answer 26

It connects wireless devices to a wired network.

Question 27

what is a hotspot

Answer 27

it is a physical location which people can access the internet wirelessly. For example, a mobile hotspot

Question 28

what is a hub

Answer 28

A basic networking device that connects multiple Ethernet devices, making them act as a single network segment; it broadcasts incoming signals to all outgoing ports (5 to 128 ports). They are used in only star topology.

Question 29

what is a switch

Answer 29

A more advanced networking device that connects devices on a network and intelligently directs data only to the device that requested it, enhancing efficiency and reducing collisions. It allows for communication between devices

Question 30

what is a router

Answer 30

It connects multiple LANs together. It routes data packets between networks

Question 31

what is a bridge

Answer 31

It is a device that connects two LANs together, filtering and limiting data packets travelling between the LANs.

Question 32

what is a firewall

Answer 32

it monitors and controls incoming and outgoing network traffic by analysing data packets and controlling what is allowed through.

Question 33

what is the purpose of digital certificates.

Answer 33

It verifies owners identity and makes sure the owner's public key is available

Question 34

what is a modem

Answer 34

It stands for modulator-demodulator and a sending modem converts digital signals into analogue signals. A receiving modem then converts it back from analogue signals into digital signals.

Question 35

what is a data packet

Answer 35

a small piece of information distributed over a network

Question 36

what is an analogue signal with examples

Answer 36

continuous wave denoted by a sine wave and varies in frequency and strength. Some examples are the human voice and a kitchen clock ticking.

Question 37

what is a digital signal with examples

Answer 37

binary digits, 1s and 0s. It is either on or off. It provides a constant and consistent signal. An examples is a smart watch.

Question 38

what is ethernet

Answer 38

It allows personal computers to contend for access to the network. It is relatively inexpensive and easy to install and maintain. It uses a twisted pair cable.

Question 39

what is bandwidth

Answer 39

How much data you can send or receive across a connection at any given time. Expressed in bits per second.

Question 40

what is file transfer protocol (FTP)

Answer 40

Used to transport/send and receive large files. It also sends configuration files and software updates for routers and switches. It uses ports for communication and encryption to protect the information being sent.

Question 41

what is simple mail transfer protocol (SMTP)

Answer 41

It is used for sending and receiving emails.SMTP is used for sending emails and POP3 or IMAP is used for receiving emails.

Question 42

what are some advantages of wireless networks?

Answer 42

Convenience: Allows users to access network from any convenient location within their primary networking location. Mobility: You are able to access the internet where ever as long as there is wifi or 4g or 5g. Productivity: Users can maintain nearly a constant connection anywhere as they move from place to place. Expandability: They can serve as a number of increased clients with existing equipment. Cost: Increase in cost for labour but equals out in no need to buy wiring.

Question 43

what are some disadvantages of wireless networks

Answer 43

Security: They aren't very secure, however, you can add security devices like firewalls and encryption in order to make your network more secure. Range: Wifi networks are usually fast for up to 10 meters. It becomes slow after that. To extend this range, you would need to add more access points or repeaters which increase cost. Reliability: Subject to a wide variety of interference. Speed: It is much slower than even slow wired networks.

Question 44

what are some advantages of wired networks

Answer 44

Cost: Relatively cheap Reliability: There are extremely reliable devices Performance: Broadband routers offer equivalent firewall compatibility inbuilt into the device. Speed: Can reach speeds for up to 10Gbps

Question 45

what are some disadvantages of wired networks

Answer 45

Setup: Need to run cables in difficult environments like floors, roofs, walls etc. Time consuming: Cables need to run from computer to computer, switch to switch and connecting them is very time consuming. Cost: Can be expensive to set up as need to drill through walls, roofs etc to connect wires.