The Internet

How It Works -

• At the bottom layer is the physical transport such as Ethernet, modem or leased line


• IP (Internet Protocol) - the lowest logical level of the Internet.
  IP handling addressing and routing and keeping track of the IP packets of information.


• TCP (Transmission Control Protocol) - a high level protocol that establishing and managing connections between two systems. It is used for most high-level Internet applications.


• High-level Internet applications such as -


• HTTP (HyperText Transfer Protocol) a set of rules for exchanging files (text, graphic images, sound, video, and other multimedia files) on the World Wide Web. Web Browsers are HTTP client.


• Email systems using SMTP (Simple Mail Transfer Protocol) for sending mails and POP3 (Point Of Presence) for receiving mails


• FTP File Transfer Protocol for data transfer from one network to another such as down load a file.

Internet Connection

Options of connection to the ISP:

• Analogue Transmission / Standard MODEM

A MODEM is required at both ends of the transmission (one at the user's end and the other at the ISP's end), maximum speed is up to 56kbps.

A 56k Modem rarely can work at it's full speed 57,600 bits per second when connected to the Internet nowadays because of -


• Internet Traffic Congestion

Although we can do very little about the congestion of Internet traffic but just to avoid to logon at peak hours see The Internet Traffic Report monitors


• Connection Bandwidth - how fast data flows on a given transmission path

You can test your connection bandwidth with Cnet's Bandwidth Meter
Guess what bandwidth you will get before the test result is shown and don't be surprised if you don't get 56k even you have a 56K Modem !

or

Choose a quiet time (when the Internet's traffic is not so busy) to download a file about 1MB to 2MB in size from a website, you then will see the Windows' download dialog showing you the speed your computer is receiving data through the Internet.


• User Ratio (User per Modem ratio) set by ISP


•   5:1 is the lowest in the industry and permits a fast connection
• 10:1 is a norm with an average-speed connection when the Modem is not fully loaded with 10 users, otherwise best to avoid logon at peak hours


• Digital Transmission / ISDN (Integrated Services Digital Network)

ISDN is a set of standards for digital transmission over ordinary telephone copper wire as well as over other media. ISDN requires adapters at both ends in order to delivery the high-speed transmission up to 128Kbps.
More about ISDN Broadband ISDN (BISDN)


• Digital Transmission / ADSL (Asymmetric Digital Subscriber Line)

ADSL operates over a normal telephone line. The signal is carried by two DSL modems, one at the user end and one in the local exchange. The modems are designed to exploit the physical transmission capabilities of the copper line to achieve higher downstream data rates from 512Kbps up to 20Mbps. 

A 'splitter' (which is a filter), one at the user end and one at the exchange end that separates the telephony signal from the DSL signal. This means that telephone calls can be made at the same time that data is being sent or received.

More about ADSL
Broadband Service Provider
Test your broadband speed


• Cable Modem (C-Modem) for cable users

Using Cable Modem network is like connecting to the Internet among a block of houses of neighbours like the cable TV. The downstream data speed of 512 Kbits/sec and upload speed of 256 Kbits/sec is allocated to each account user. The data speed will be shared among the users in that block if there is more than one user online.


• FTTH

Fiber-to-the-home broadband connections, or FTTH broadband connections, or Fibre Optic Broadband – up to 100Mbps
Check fibre optic broadband available in your area


• Satellite Internet access

This is normally regarded as an expensive option but provide Internet access to rural area where Dail-up or Broadband is not available.
More about Satellite Internet access