The Internet Explained

 

The aim here is not to blind you with technology, but to attempt a simple explanation of how the Internet works.

We look at who provides the Internet service, the devices involved, and how that Internet delivers information back to your computer or mobile phone.

Internet Service Provider

Our start point is access to the Internet.

Internet Service Providers come from various backgrounds like BT Internet(traditional communications), Virgin(cable services), The Cloud(wifi) and Vodafone(mobile services),  and hence Internet access can be via a physical  broadband connection(copper/fibre/cable) to your home or office or via wireless services(3G mobile or wifi) to your mobile/smart phone or iPAD/ Tablet.

You pay them money, they offer Internet Access and control the speed at which data is transferred between you and the Internet.

Internet Ready Device

Connection to the Internet is via an Internet Ready device like:

  • Mobile/Smart phone
  • PC
  • Lap top
  • Gaming console
  • etc.

Each Internet Ready Device has its own processor(engine) on which an operating system(set of software programmes) controls what you do at any point in time.

The faster the processor and more efficient the operating system,  the quicker your Internet Ready Device can communicate with the Internet.

Ones and Zeros

It all starts with ones and zeros. That is the basis of all digital communications from the Internet, your DVD, HD TV, everything is a stream of ones and zeros which when grouped together form pieces of everyday information.

Bits and Bytes

A bit is either a one or a zero.

You will hear the term Mbps when folks to about Internet speed.

A Mega Bit per second is a million ones or zeros per second.

A Tera bit per second is a trillion ones and zeros per second, and so it grows as the technology improves, to generate and send such huge amounts of information around our planet.

On your  computer, information/data is stored as chunks of 8 bits and is call a Byte.

When you download information from the Internet it will be displayed as MegaBytes(MB).

Addresses

There are billions of humans using billions of Internet Ready Devices. How do they know who is who?

In the early days  there were many difference schemes to solve the problem but one solution won through. It is called the Internet Protocol(IP), a set of digits which allows the Internet Service Provider to identify all the users on their network, and locate users anywhere in the world.

Whilst most Internet users never get involved with IP addresses,  you should think of them like a Post code you put on an envelope.

The Network

The simple way to think of the Internet is as a Postal network. When I want to send a letter, I write it out, place it in an envelope, add the address and post code of the destination, stick on a stamp and post it.

My local postal service reads the post code and then moves it on to the appropriate local sorting office from where the post man delivers the letter.

If the destination is overseas, the letter will go via plane, to a national sorting office in the required country, and then on to the local sorting office and so on.

On the Internet, instead of paper you have typed something into your computer, say an email or a web address.  All those ones and zeros are grouped together into packets(envelopes) and each packet has the IP address of where on the Internet your data should go next(post code).

Also if the address of the destination is wrong, the Internet will return to sender just like a postal service.

Moving your Email or getting to your Web site.

Instead of postal vans and planes, the Internet is a mass of cables(copper to your home typically and fibre between cities and countries).

Your Internet Service Provider is the postman, moving the data towards its destination.

If the destination is also a customer of your Internet Service Provider they will recognise the address and deliver it accordingly.

If not it goes to a Internet Exchange Point(IXP) which links all the national Internet Service Providers together and offers access to the rest of the world should your envelope be destined for foreign computers. The IXP can be thought of as a national postal sorting office.

When you pay your Internet Service Provider some of that money goes to the IXP, who in turn buys bandwidth from the big cable companies that link the worlds Internet services together. This is the equivalent of the air fare and plane used by the post service

So we now have a way of getting ones and zeros across the world and back again, but we are missing our address book, our Yellow pages, without which we don’t know where anyone actually lives.

Worldwide web

Sir Timothy Berners-Lee whilst working at CERN in Switzerland came up with an idea, which today is known as the worldwide web.

Again, the details are complex, but the overall structure he invented is simple, which means that most of us never need to worry about IP addresses when we use the Internet.

The first key element is a Domain name.

A Domain name can be thought of as a key address, say a city like London or York . All email and web communication is based on a domain name.

Companies register and buy unique Domain names, so :

bbc.co.uk  is a domain name

The Internet community has established a worldwide group that controls and registers domain names.

A domain name is split into secondary part in our example bbc and a top level element.

These top level elements can be:

generic  –  .com or .net or .info(which are the most expensive to own)

country based  – co.uk, .co.ie, co.de

sponsored  – owned by specific associations like .museum or .gov

Altogether, they build a unique domain name(address)

www.bbc.co.uk.

The Domain name is then linked to the IP address of the computer, on which you have put all the information you wish to share.   Alternatively, it is linked to a Email server(like a company post room) from which the emails are sent to their destination i.e. Fred@bbc.co.uk.

A Domain Name Server(DNS), is a device which holds domain names and their associated IP address.

The Internet community runs various Domain Name Servers around the world which regularly update each other, creating in effect your worldwide Yellow Pages.

Once your new domain is active, the domain name servers distribute the name(and IP address)around the world.

Hence most users never deal with IP addresses.

Hosting a Web Site

Most people cannot afford all the equipment to set up a web site.

A Hosting company is in effect a large computer, a piece of which you rent, put on your information and they run and maintain everything.

This site is hosted by Sizzle Media

Search Engines – Google, Bing.

The Domain Name Servers around the world  link domain names to IP address.

Search Engines, continually search the associated web sites storing key words(and the links).

The links are known as Universal Resource Locators or URLs.

So for the bbc.co.uk they may store key words like Blue Peter with the URL  http://www.bbc.co.uk/cbbc/bluepeter/

Hence when you type Blue Peter into a search engine, one of the responses will be http://www.bbc.co.uk/cbbc/bluepeter/.

In reality Google, Bing etc. are commercial operations that charge  companies to ensure their web site always shows up when you type in an associated key word. Look at all the sponsored banners on any page.

Equally, if your own web site is popular, or key words on your site are regularly used, your site will appear higher on each search page.

PhoneFacts

To set up this web site I bought the domain www.phonefacts.co.uk which means I can be chris@phonefacts.co.uk.

I bought some computer space from a Hosting company and put these pages on that computer. That same company has an email server, which now can handle emails to @phonefacts.co.uk.

That computer has its own IP address

The Domain Name Server in the UK registered phonefacts.co.uk and distributed to all the others servers worldwide.

The Search engines pick up the registration and key words(like 3G, Smart phone etc.), and if and when someone in Brazil wants to find a simple guide to the Internet he/she may end up here.

Equally chris@phonefacts.co.uk allows my Brazilian friend to contact me via email.

Leave a Reply