Unit 5:Wide area networks Flashcards Preview

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Flashcards in Unit 5:Wide area networks Deck (36)
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1
Q

what is a fiber optic cable

A

connects various parts of a network. Different buildings, same buildings ,a campus environment and other wide areas

2
Q

why would you use fiber optic cabling instead

A

the speed and the lack of attenuation

3
Q

WAN

A

it is not confined to one area and can be owned by multiple organizations

4
Q

what is an example of WAN

A

the internet, aka WAN or GAN

5
Q

what is the function of WAN

A

to connect users and applications from different LANs

6
Q

Gateways

A

these are devices that provide connectivity between 2 r more network segments , aka protocol converters

7
Q

router

A

can also act as a gateway. A router can see both the mac address and the IP addresses but cannot repackage

8
Q

name the 3 layers that a router contains

A
  • physical layer
  • datalink layer
  • network layer
9
Q

Transmission

A

radio waves are used for for wireless transmission of sound, messages or information as well as for communication with sea vessels and aircraft navigation

10
Q

satellite communication

A

the use of satellite technology to provide voice and video calling ,internet ,television and radio channels. They can span long distances and can operate under circumstances or conditions which would make other forms of communication impossible

11
Q

what are the features of satellite communication

A

=the satellites used in satellite communications are usually in geostationary orbit.
=they are available globally .Not just on land but at sea as well. Large distances can be covered quite easily
=very reliable unlike other forms of communication
=expensive to setup ad has higher data costs
=more secure than other forms of communication and used is used by the military
=also provide weather information
=can be helpful in times of disasters as the services rarely fail.
=high amount of data can be transmitted with the help of satellites.

12
Q

what does satellite communication usually comprise of

A
=transponder
=antenna
=communication payload
=switching systems 
=command 
=control system
13
Q

microwave

A

a communications system that uses a beam of radio waves in the microwave frequency range to transmit video, audio or data between two locations which can be from just a few meters apart to several kilometers apart

14
Q

cell?

A

A mobile phone network consist of many signal areas called cells. They overlap with each other to create coverage for a large area .Within each cell there is a base station or a mobile phone tower, which sends and receives the mobile transmissions .Cells will be smaller in size in a more densely populated areas because of the any users in the area. Devices with a sim card can connect to a mobile network using 3G,4G,5G and LTE .

15
Q

3G

A

this is the third generation of mobile data technology. Supports many larger data formats such as HTML pages, videos and music .The speeds were still pretty slow ad mostly required pages and data specially formatted for these slower wireless connections .

16
Q

LTE

A

Long Term Evolution is an improvement over 3G but not substantial enough to qualify as a new generation. Made improvements over 3G but technically not 4G

17
Q

4G

A

provided faster connection speeds and mobile hotspots .Unlike 3G, 4G allows users to view digital media on their mobile devices ,including streaming videos ,rich multimedia apps, and high-quality music. Users can start watching a movie in seconds without worrying about long load times and buffering

18
Q

5G

A

presumed to be smarter ,faster, and more efficient than 4G.It promises mobile data speeds that far outstrip the fastest home broadband network currently available

19
Q

Low latency

A

is a key difference 4G and 5G.This means that you can download and upload files much faster than before ,without worrying about slow connectivity. You can be able to watch a video almost immediately without having to experience any buffering time.

20
Q

Wi-Fi calling

A

let’s you make a call to a phone number over the internet at no additional cost to the data cost. It is also useful when you can connect to a WIFI network but are unable to connect to a cell phone network. WIFI calling is a function that is installed on your phone and can be used by applications such as facetime, WhatsApp of Facebook.

21
Q

Fiber

A

Fiber uses fiber optic cables to transmit data. Fiber internet is also referred to as superfast broadband. This means that data has the potential to travel at the speed of light and isn’t affected by your distance from the exchange.
=fiber internet users enjoy the fastest seeds which is particularly beneficial TV streaming services ,online gaming .
=beneficial to large businesses conducting most of their work online or via the cloud.
=It is cheaper than ADSL broadband.

22
Q

ADSL

A

uses telephone lines to transmit data along copper cables from your nearest telephone exchange to your home or office. The further you are from the exchange ,the slower your speeds will be. ADSL is being replaced by faster fiber connections.
=ADSL Uses telephone lines to transmit data along copper cables from your nearest telephone to your home or office. Copper cables are often affected by bottlenecks: the more internet traffic, the slower your download speeds-just like traffic on the roads.
=ADSL provides acceptably perfect speeds form 1mbph to 40mbph for most internet activities, including browsing and email

23
Q

Bandwidth

A

is the amount of data that can be transmitted from one point to another in a certain amount of time

24
Q

internet speed

A

the rate at which information or data travels from the web to your device, be it a computer, tablet of smartphone. It is measure in megabits per second.

25
Q

name the 3 email protocols

A

SMTP
POP3
IMAP

26
Q

SMTP

A

Simple mail transfer protocol is used when email id delivered from an email client to an email server or when email is delivered from one email server to the other
=they use port 25
=usually used for outgoing emails while incoming email is usually uses POP3 or IMAP

27
Q

POP3

A

Post office protocol allows an email client to download an email from an email server.
=offers no additional feature other than download.
=designed to instruct the email client to download all available email from the server and then delete the mail from the server and finally disconnect from the server .
=POP3 normally uses port 110

28
Q

IMAP

A

Internet message access protocol is like POP3 protocol ;the email client can download email form the email server .
=offers more features than POP3 .
=allow the user to keep their email on the email server which is useful if you use many devices to access the email.
=require greater disk space for each client on the server and more CPU resources on the client’s machine than POP
=Usually uses port 143

29
Q

Web protocols

A

a protocol is simply a set of rules which enable the connection ,the communication and data transfer between 2 places on a network.

30
Q

name the 2 transfer protocols

A

=HTTP

=HTTPS

31
Q

HTTP

A

is the standard protocol for transferring web pages and their content across the internet. Most of the web will use HTTP as the default protocol ,this means if you simply type in a URL the browser will automatically add http in front of the web address

32
Q

HTTPS

A

Hyper text transfer protocol over secure socket layer is a secure version of http .It is used mainly on web pages that ask you to provide personal or sensitive information such as credit cards details.

33
Q

how can you the SSL certificate

A

check the validity of the certificate by double clicking on the browser’s padlock icon. The padlock icon only appears when you view a secure site.

34
Q

name the 2 download protocols

A

=FTP

=WebDAV

35
Q

FTP

A

File transfer protocol is used to transfer files across the internet. It is used for displaying the file in your browser .FTP is usually simple to transfer the file from one computer to a specified location on anther computer. You can use it to transfer the files from your computer to a remote computer or to transfer from the remoter computer to your local computer.

36
Q

WebDAV

A

Web Based distributed authoring and versioning is an extension of the http protocol used for communication between client browsers and web servers. It is an open standard which can be implemented on UNIX servers as well as Windows servers. It is widely used for applications that require users to collaboratively edit and manage files on remote servers.