CAT Module 2 Notes Maria Vougdis
Internet Services and Connections:
Introduction:
- internet is a worldwide computer network linked using a form of communication media
- network: link of two or more devices over a geographical location
- communication media can be → telephone lines, fiber cables, satellite, cellular and microwaves
- WAN is a Wide Area Network which spans over countries and continents
- the purpose of a WAN is to facilitate the sharing of resources
- e.g. Checkers network link around the country
- GAN → Global Area Network
Internet Connections:
Internet Service Provider
- ISP is a company that sells permanent and fast connection to the internet
- e.g. MWEB, TelkomSA, Cell C, Vox
- services offered by ISPs are → email, internet access, fax-to-email
Criteria for types of internet connection
- internet connection can be broadband or baseband , most people prefer broadband
- broadband is a high-speed and high-bandwidth connection
- bandwidth is the total amount of data transmitted from one point to another in a certain period of
time
- measured in Kbps or Mbps
- when choosing an internet package:
▫ mobility ▫ speed of the line connection
→ fixed connection [at a certain place] → price is dependent on speed of line
→ mobile [able to move]
▫ cap
▫ shaped or unshaped → data limit on bundle chosen
→ shaped - gives preference to certain service [capped/uncapped]
[email] → upload and download limit measured in Gb
→ unshaped – all internet services given the → throttled - ISP slows down connection after
same priority certain limit is reached [stated in AUP]
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,CAT Module 2 Notes Maria Vougdis
Wired versus Wireless
- wired connections involve ADSL or fiber:
▫ ADSL
→ Asymmetrical Digital Subscriber Line
→ copper cables used
→ connection to internet with a telephone line
→ split into two channels; internet and phone
▫ Fiber
→ data transmitted through glass/plastic tubes
→ can carry more bandwidth
→ FTTH [Fiber to the home]
- wireless connections involve cellular technology:
▫ Cellular
→ wireless existing network
→ provides mobile access to the internet
→ 3G/4G/LTE/5G are the different generations of cellular technology
- advantages and disadvantages:
▫ advantages of wired ▫ disadvantages of wired
→ ADSL is cheap → fiber is expensive
→ fiber has a high bandwidth → ADSL has lower bandwidth capability
→ fiber has a fast connection over large area → ADSL has speed drop and signal area is small
→ both ADSL and fiber have stable connection → ADSL can have electrical interference
▫ advantages of wireless ▫ disadvantages of wireless
→ mobile access → if in an area with poor coverage, limited or
slow access
→ never escape reality, information overload
→ limit on the amount of data available
→expensive
Wi-Fi [802.11]
- connecting to ADSL or fiber connection wirelessly within small coverage are
- known as a hotspot
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, CAT Module 2 Notes Maria Vougdis
- create Wi-Fi network within home to allow mobile devices to connect to network
- mobile devices benefit as it is fast and cheap
- need to enter password to gain access to network
Internet access using smartphones
▫ always on and everywhere - never without connectivity
▫ fast and reliable - don’t have to wait for data
▫ hassle-free connection - always connected, don’t have to think about how to connect
▫ mobile devices
- most people expect mobile connectivity for mobile devices
- these devices are always on and don’t have to boot up before use
- always connected to received emails, SMSs and VoIP
- 3G/4G is built into device to connect using cellular technology when on the move and Wi-Fi when in
range
Internet Services:
Introduction
- services the internet offers
- allow increased communication between people
Real-time messaging
- instant messaging is SMS without cost
- WhatsApp is an IM application
- allow all forms of media [text/picture/video]
- use VoIP technology
▫ advantages ▫ disadvantages
→ chat with more than one person at a time → people aren’t who they claim to be [catfish]
→ interact with others despite location → leads to anti-social behaviour
→ cost effective → creates opportunity for cyber-stalking
→ easily switch from voice to video call
→ game features added
VoIP
- voice over internet protocol
- group of technologies for the delivery of voice and media communications
- voice and media is transmitted through a network
- allows telephone calls to be made over the internet
- e.g. Skype
3|Page
Internet Services and Connections:
Introduction:
- internet is a worldwide computer network linked using a form of communication media
- network: link of two or more devices over a geographical location
- communication media can be → telephone lines, fiber cables, satellite, cellular and microwaves
- WAN is a Wide Area Network which spans over countries and continents
- the purpose of a WAN is to facilitate the sharing of resources
- e.g. Checkers network link around the country
- GAN → Global Area Network
Internet Connections:
Internet Service Provider
- ISP is a company that sells permanent and fast connection to the internet
- e.g. MWEB, TelkomSA, Cell C, Vox
- services offered by ISPs are → email, internet access, fax-to-email
Criteria for types of internet connection
- internet connection can be broadband or baseband , most people prefer broadband
- broadband is a high-speed and high-bandwidth connection
- bandwidth is the total amount of data transmitted from one point to another in a certain period of
time
- measured in Kbps or Mbps
- when choosing an internet package:
▫ mobility ▫ speed of the line connection
→ fixed connection [at a certain place] → price is dependent on speed of line
→ mobile [able to move]
▫ cap
▫ shaped or unshaped → data limit on bundle chosen
→ shaped - gives preference to certain service [capped/uncapped]
[email] → upload and download limit measured in Gb
→ unshaped – all internet services given the → throttled - ISP slows down connection after
same priority certain limit is reached [stated in AUP]
1|Page
,CAT Module 2 Notes Maria Vougdis
Wired versus Wireless
- wired connections involve ADSL or fiber:
▫ ADSL
→ Asymmetrical Digital Subscriber Line
→ copper cables used
→ connection to internet with a telephone line
→ split into two channels; internet and phone
▫ Fiber
→ data transmitted through glass/plastic tubes
→ can carry more bandwidth
→ FTTH [Fiber to the home]
- wireless connections involve cellular technology:
▫ Cellular
→ wireless existing network
→ provides mobile access to the internet
→ 3G/4G/LTE/5G are the different generations of cellular technology
- advantages and disadvantages:
▫ advantages of wired ▫ disadvantages of wired
→ ADSL is cheap → fiber is expensive
→ fiber has a high bandwidth → ADSL has lower bandwidth capability
→ fiber has a fast connection over large area → ADSL has speed drop and signal area is small
→ both ADSL and fiber have stable connection → ADSL can have electrical interference
▫ advantages of wireless ▫ disadvantages of wireless
→ mobile access → if in an area with poor coverage, limited or
slow access
→ never escape reality, information overload
→ limit on the amount of data available
→expensive
Wi-Fi [802.11]
- connecting to ADSL or fiber connection wirelessly within small coverage are
- known as a hotspot
2|Page
, CAT Module 2 Notes Maria Vougdis
- create Wi-Fi network within home to allow mobile devices to connect to network
- mobile devices benefit as it is fast and cheap
- need to enter password to gain access to network
Internet access using smartphones
▫ always on and everywhere - never without connectivity
▫ fast and reliable - don’t have to wait for data
▫ hassle-free connection - always connected, don’t have to think about how to connect
▫ mobile devices
- most people expect mobile connectivity for mobile devices
- these devices are always on and don’t have to boot up before use
- always connected to received emails, SMSs and VoIP
- 3G/4G is built into device to connect using cellular technology when on the move and Wi-Fi when in
range
Internet Services:
Introduction
- services the internet offers
- allow increased communication between people
Real-time messaging
- instant messaging is SMS without cost
- WhatsApp is an IM application
- allow all forms of media [text/picture/video]
- use VoIP technology
▫ advantages ▫ disadvantages
→ chat with more than one person at a time → people aren’t who they claim to be [catfish]
→ interact with others despite location → leads to anti-social behaviour
→ cost effective → creates opportunity for cyber-stalking
→ easily switch from voice to video call
→ game features added
VoIP
- voice over internet protocol
- group of technologies for the delivery of voice and media communications
- voice and media is transmitted through a network
- allows telephone calls to be made over the internet
- e.g. Skype
3|Page
