Communication and the Internet : Unit 21 :Network Flashcards
1
Q
What is a network?
A
an arrangement of computers and other devices connected together to share resources.
2
Q
What is network service?
A
- an app running on a server that provides facilities / operations such as data storage, printing pr communications.
3
Q
What are the 5 advantages of networks?
A
- Users can share files
- Users can share peripherals: printers and connections to other networks.
- Users can access their files from any computer on the network.
- Servers can control security, software updates and backup of data.
- Communication with other people, eg: email and social networking
4
Q
What are the 3 types of different types of networks?
A
Local area network
Wide area network
Personal area network
5
Q
What is LAN?
A
A local area network is a network that covers a relatively small geographical area, often a single site.
6
Q
What is WAN?
A
Wide area network - a network that covers a large geographical area. it connects two or more LANs and is usually under shared ownership.
7
Q
What is WLAN?
A
A wireless local area network is a local area network in which connected devices use high frequency radio waves to communicate.
8
Q
What is PAN?
A
personal area network is a network used for data transmission over short distances by computer devices, such as laptops, mobile phones, tablets, media players, speakers and printers.
9
Q
What is Bluetooth?
A
a protocol for the short-range wireless interconnection of mobile phones, computers and other electronic devices.
10
Q
What are the two main models relating to computer networks?
A
- client-server network
- peer-to-peer networks
11
Q
What is the client-server network?
A
a network that has at least one server to provide services to the client computers
12
Q
What is the peer-to-peer network?
A
a network that doesn’t have any dedicated servers. Each computer in the network can act as a client.
13
Q
What is network topology?
A
describes how the devices on a network are connected together.
14
Q
What are the four network topologies?
A
- bus.
- ring.
- star.
- mesh.
15
Q
What is the internet?
A
- a worldwide system of interconnected networks that enables information to be exchanged and shared.
16
Q
What is communication media?
A
- communication media are how the means by which data is transmitted between devices on a network.
(coaxial cable, fibre optic cable, and microwaves are all forms)
17
Q
What are the two ways that computers can be connected together to form a network?
A
- wired.
- wirelessly.
18
Q
How are the characteristics of wired and wireless networks impact on performance?
A
- speed.(wired more than wireless)
- range.(wireless more than wired)
- latency. (wireless more than wired)
- bandwidth.(wired more than wireless)
- bit error rate/ rate of corruption.(wireless more than wired)
19
Q
What are the 3 types of communication media?
A
- coaxial cable.
- fibre -optic cable.
- copper cable.
20
Q
What is the protocol?
Eavesdrop?
A
- a set of rules that govern how communications on a network should be formatted and what data they should include.
- eavesdrop having unauthorized sight of data being sent from one computer to another over a network.
21
Q
What are the 4 disadvantages of networking?
A
- Increased security risks to data.
-Malware and viruses spread very easily between computers, - If a server fails, the computers connected to it may not work.
- The computer may run more slowly if there is a lot of data traveling on the network.
22
Q
What are the 3 benefits of being able to measure the speed of a network?
A
- allows you to discover whether an equipment upgrade is necessary,
- estimate how long it will take to download a file.
- discover whether actual performance lives up to the promises made by the service provider.
23
Q
How to calculate the time needed to transmit a file?
A
- Convert file size from megabytes to bits.
- Convert the transmission speed from Mbps to bits per second.
File size in bits --------------------------------------- transimission speed for bits per second (Mbps-- bps)
24
Q
What is latency?
A
latency is the delay encountered by data travelling through a network.
25
What are the 3 steps in how client-server networks work?
1. Connection Establishment:
Step 1: Request from Client: The client initiates a request for information or service by sending a request to the server. This request is in the form of a specific command or data query.
Step 2: Server Response: Upon receiving the request, the server processes it and sends back a response. This response could be the requested information or an acknowledgment of the command execution.
Data Transmission:
Step 3: Data Exchange: Once the connection is established, the client and server engage in data transmission. The client might send further requests for additional information or services, and the server responds .
Termination of Connection:
Step 4: Session Termination: When the client no longer requires services the client initiates the termination of the connection.
Step 5: Closing Connection: The server acknowledges the termination request, and both the client and server close the connection.
26
What are the 3 features of client-to-server?
limitations.
- cannot switch roles.
- back up and store data centrally.
- provide centralized control.
- can be expensive and difficult to run.
27
What are the 5 features of peer-to-peer?
- no dedicated servers.
- each computer is equally in responsible and each can work as a both client and a server.
- each computer is responsible for data.
- simpler to set up and maintain
- no managed security and back up
28
What are the 4 advantages of bus topology? 3 disadvantages of bus topology?
Ad:
- less cable is needed.
- no specialized device.
- simple to set up,
- Easy to add new device.t
Dis:
- if bus fails then no devices can communicate,
- data collisions occur, lowering performance.
- security issue as all devices receive all data packets sent
29
What are the 4 advantages of Ring topology? 3 disadvantages of ring topology?
Ad:
- No specialized device (like a hub or a switch)
- Simple to understand and set up.
- no data collisions as only the token is sent around.
30
What are the 4 advantages of star topology? 3 disadvantages of star topology?
Ad:
- if one cable or device fails the other devices will be unaffected.
- cables aren't shared so few data collisions
- high performance.
- easy to add new devices.
Dis:
- expensive to install, due to lots of cabling and central device.
- central device may slow down the network.
- if central device fails, then so will the whole network.
31
What are the 4 advantages of mesh topology? 3 disadvantages of mesh topology?
Ad:
- if one cable stops working there are backup services.
- fast as they can communicate directly.
- few data collisions will occur.
Dis:
- if the bus fails then no devices can communicate.
- data collisions occur lowering performance.
- security issue as all devices receive all the data packets sent.
32
What are the 4 advantages of wired connections? 3 disadvantages of wired connections?
Ad:
- speed: faster than wireless connectivity.
- security: not easy to intercept or eavesdrop on data.
- Reliability: less susceptible to interference than wireless connectivity.
- Stability: there may often not be any congestion.
Dis:
- expensive to install and reconfigure.
- Limited Mobility as it requires many cables at a premise.
- Vulnerability to Physical Damage: Wired connections are susceptible to damage from physical factors.
33
What are the 4 advantages of wireless connections? 3 disadvantages of wireless connections?
Ad:
- No need for a cable to connect devices or to the Internet.
- Allow users to use their own device.
- A wider range of devices can communicate with each other.
Dis :
- Data transmission speeds can be slow.
- there can be interference from other wireless devices can adversely affect performance.
- data needs to be encrypted in order to prevent eavesdropping or interception.
34
What are protocols?
protocols are a set of rules that control how communication between devices are formatted.
35
What are email protocols?
this protocol controls how emails are transported from one device to another.
36
What are the 8 things protocols might include?
37
What are the 3 main email protocols used?
- SMTP - simple mail transfer protocol.
- POP3 - post office protocol.
- IMAP - internet message access protocol.
38
What are the 3 network protocols?
- Ethernet.
- Wi-fi
- TCP/IP
39
What is the ethernet?
- Ethernet is a family of protocols that are used in wired LANS.
40
What is Wi-Fi?
-Wi - fi is digital communications protocol that sets out how data is transmitted on wireless LANs.
41
What is TCP?
- Transmission Control Protocol provides a reliable connection between computers.
42
What is TCP/ IP?
- TCP/ IP (transmission control protocol/ Internet Protocol) is a protocol stack it is a collection of protocols that will work together.
43
What are the comparisons of characteristics of wired and wireless networks on performance? a. Range b. Latency
a. Wireless connections have a far shorter range than wired.
b. Latency tends to be worse with wireless connections over wired-latency
44
What is a packet?
- a small quantity of data being sent through network.
45
What are the protocol layers in TCP/IP?
- Application.
- Transport.
- Internet.
- Link.
46
What is web server?
-it is a powerful computer system that stores web pages and any multimedia that the pages might contain.
47
What are the 6 protocols of the application layer?
- FTP
- HTTP
- HTTPS
- SMTP
- POP
- IMAP
48
What are the benefits using networking layers?
- it makes the overall model easier to understand.
- each layer is specialized to perform a particular function.
- Different layers can be combined in different ways.
- one layer can be developed or changed without affecting the other layers.
- makes it easier to identify and correct networking errors.
- provides a universal standard for hardware and software.
