الجمعة، 3 مايو 2013

Trout with vegetables



Ingredients:

1 kg fish;
4 onions;
2-3 carrots;
1 celery root;
2 coffee cups oil;
2 tomatoes;
6-7 cloves of garlic;
black pepper;
pinch of thyme;
1 coffee cup white wine;
½ lemon;
2 tablespoons chopped parsley;
salt.

Preparation:

  1. Chop the onions, the carrots and the celery.
  2. Put them in a pan and stew them in oil.
  3. Add 2 grated tomatoes, chopped garlic cloves, black pepper and thyme  and salt.
  4. Put the trout in slices or in pieces which are rolled in flour to a baking pan and add the wine and 1 tea cup warm water.
  5. Put lemon slices over the fish and the stewed vegetables.
  6. Sprinkle with parsley and oil and bake in moderate oven.

Best Steakhouse in New York can be the Ideal Place for Celebrations


The tasty food and the inviting aroma of the delicacies are a sure shot that can be found in the best steakhouse in New York. Every person visits a steakhouse to enjoy the food court and the ambience. It is best place for enjoying parties and celebrations. There are some or the other moments in your life that calls for celebrations. The occasion can be your birthdays, kiddy parties or even anniversaries. The best steakhouse in New York offers varieties of facilities with the excellent quality steak food. You can also enjoy music, while dinning at the best steakhouse.

Are you worried about selecting the special venue for your party? The best steakhouse inNew York is the ideal place to go about it. You should take special care in selecting the top class steakhouse among the best available ones. The appropriate venue is the prestige issue in the matter of party celebrations. If you are not able to organize a proper venue, your guests might get the chance to criticize you. A party is a special occasion when you meet your relatives and close ones. It is the best time to throw a pompous party for them and venue matters a lot.

Best steakhouse in New York has lip-smacking food. Though, the taste might differ in every type of steakhouse. The taste difference occurs because of the method of preparation. There are numerous steakhouses that lay emphasis on dry and medium cooked steak food, while many other prepare fully cooked steak in a steakhouse. A variety of people prefers medium cooked steak. They have the notion that medium cooked steak is juicier than the fully cooked steak. If you also have a special liking for the juicy steak, then you can visit the steakhouse that prepares medium cooked steak and order exactly that.

There is a variety of steakhouse that offers fully cooked steak food. Now, it all depends on your liking and preference. Generally, the steak is made of beef. You can also enjoy the sea food at the steakhouse. After all, it is necessary for the best steakhouse in New York to keep every type of non-vegetarian food. They are catering to a large number of people, who are crazy for steak food and sea food. The love for steak food compels the people to visit such places frequently.

If you are planning to organize a party on weekends, then go for the best steakhouse in New York. There are various steakhouses that reserve the weekends for special parties. You can also enjoy the loud music during the parties. Such type of music cannot be enjoyed on the usual dinning days. Another important aspect of having lunch or dinner at the best steakhouse in New York is that the food is affordable. You can enjoy the best food court at reasonable rates. These features about the best steakhouse are highly beneficial for their business. It is because they act as the crowd pullers. The combination of best ambience, best food court and best prices will enable the customers to pay frequent visit to the best steakhouse. Isn’t it?

Impressive Solar Consumer Products


Being in the business of solar energy, we see a lot of new and exciting products long before they hit the store shelves.  We attend a lot of tradeshows and industry conferences, and it never ceases to amaze me how passionate people are about their newly-developed applications.  While it is nowhere near the end of the year, we felt we would share some of these amazing products with you, our loyal readers.

One of the most interesting products we have seen this year comes out of a university in UK.  It is being called the "Sun Trap", and it is garnering a lot of excitement in the world press.  It is not exactly a revolutionary idea, but it certainly is an innovative use of existing technology.  It is a handbag designed using photovoltaic material as an exterior, while the interior of the purse is lined with electroluminescent material.  When the bag is opened, the interior lights up!  It is powered by a small battery that is continually charged by the sun throughout the day.  No more searching for your keys in the night!

Another fine product that we see as being incredibly practical is the solar panel for notebook computers.  This an incredibly handy tool for those people who spend a lot of time outdoors.  We have all had situations when we are far from an outlet and the laptop dies.  Isn't that the worst?  Well, this product has the potential to solve that problemso long as a light source is available.  I plan on taking mine on my next camping trip!

There are also some awesome new products designed for use in your yard or garden.  I am particularly keen on some of the great garden lighting systems that have recently been released.  These are basically small lights that are used to illuminate garden paths and walkways.  They are charged throughout the day by the sun, and they stay lit well throughout the night.  There are also new solar powered rodent repellers that are an excellent alternative to using chemicals or traps to keep rodents out of your garden.

These are just a few of the exciting products that have seen the light of day.  Engineers and inventors around the world are working to develop some wonderful new products.  It is very refreshing to see that people are devoting time and effort into developing sustainable energy applications.  It is only a matter of time before all energy products are designed with the interests of sustainability in mind.

الخميس، 2 مايو 2013

Guide to Buying a Webcam


How web broadcasting works

Webcams are those handy little cameras that attach to your PC and send images to a web page that can be viewed by others. This enables you to share daily life events with friends and family in other parts of the country or the world, or to arrange a video-conference with colleagues and maintain long distance relationships of all kinds. Of course the number of ways to use this technology is limited only by your imagination.

Web Cameras

But before you buy a webcam, it pays to understand a little about how the technology of broadcasting images over the Internet works. Of course, if you\'re a full bottle on this already, you can skip this section and go straight to browsing the options on Myshopping.com.au where you can compare products and suppliers, their specifications and prices.

Webcams provide \'real time\' images of people; places and events that can be viewed \'live\' on a web page. The broadcasting end has a camera that captures the images, feeds them into a computer to an ISP and out to viewing pages across the Internet. There are two different types of broadcast: streaming images, where the images are a constant stream downloaded in video format; or Java, where the images are captured at fixed time intervals and refreshed on the web pages at a rate fixed by the broadcaster.

The Applications - What are you intending to broadcast, and to whom?

There is a wide range of uses of webcam technology. Some examples include personal \'Big Brother\' style diaries, sharing of family events, workplace security, video conferencing, virtual tourism, road traffic management, weather watching, event broadcast and a host of others.

Before you make a choice about any webcam equipment, it helps to decide exactly how you want to use the technology, in other words, what you are intending to broadcast. This decision will impact upon the type of camera you use, and how you use it.

A second consideration is, who will be viewing your content? What level of quality is expected? This will help determine the type of camera you use, the software involved and your Internet connection. Of course, your Internet connection may be a limitation on how much you can do.

The requirements for video conferencing are different from the requirements of workplace security, which are different again from the requirements of sharing a family event.

The physical components

There are a number of physical components required to make web cam technology work. At the top of the list is the camera itself. Then, depending on the type of camera you use and the way in which you want to deliver the content to the Internet, you may need to incorporate video capture hardware in your computer. Some software is required to help you process the data, and Internet connection is required and a web page into which the data is fed.

CAMERA CHOICES

Your choice of camera depends somewhat on what you are intending to show. If you need to reach a large public audience yo may want good quality camcorder or megapixel camera that captures high quality images. If it\'s just for seeing who\'s at your front door or keeping an eye on the kids in their playroom, then it may not need to present high quality images. If you are intending to use it outdoors, it will need to be weather proof and you may need to consider sun and UV protection. Available power supply and any robotic requirements for camera movement and focus are extra considerations.

Dedicated webcams

The most basic webcams connect to a PC using a simple USB connection. A wide range of cameras with accompanying software at a range of prices is available for this type of application. Simply search though Myshopping.com.au to compare prices and specifications. Dedicated webcams are simple to install and easy to use, but come with limitations that affect the quality of the images, such as low number of frames per second (refresh rates) and resolution (pixels per inch).

Camcorders and security cameras

Higher quality images and more camera control come from using camcorder and security cameras. To use these devices you will need to add a video capture card to your PC. Once you have that installed however, you can use a wide range of cameras from broadcast cameras to miniature spy cameras. You can include variable lens options, filters for daylight and low light situations, as well as robotic controls for panning and focus adjustments. You can search through Myshopping.com.au for camcorder selections.

Integrated cameras

An integrated camera combines the camera and the optical hardware with a video server, and as such requires no additional software. They can be used in network situations or as stand-alone devices for monitoring progress on a construction project for example.

Megapixel cameras

Network megapixel cameras combine network capability with high quality digital camera technology. These cameras offer excellent quality but this creates large files sizes, therefore they have limited application in constant streaming video. However for interval refreshed archive image collection, they are ideal, providing a constant record and high quality. You can search through Myshopping.com.au for digital camera selections.

SOFTWARE

If you are not using an integrated camera solution, you will need to install an encoding program like Webcaster or MediaCaster to transfer your images to a web page.

At the receiver end, when web surfers browse the internet and wish to view live video on the web for the first time, they will need to download dedicated applications that show the content such as an ActiveX control, Windows Media player, Flash player or the like.

INTERNET CONNECTION

Finally, you need an Internet connection. The hardware you will need may include a modem for dial-up connection, or modem/router for a broadband solution. Naturally the higher the quality you want, or the faster refresh rate you want, the more bandwidth you will need. ADSL (Broadband) is going to offer you the best solution, but keep in mind what your Internet connection when you are making choices of cameras and feeder software.

Webcam applications work well with wireless solutions. Make sure when you are purchasing a camera or network video solution that it is compatible with any wireless system you may be using in a LAN.

Key considerations

The specifications that are variable with webcam applications, and are affected by camera type, web interface and Internet connection, include the number of frames per second and the image resolution.

Frames-per-second is the number of times a still image flashes by in a second to give the appearance of moving pictures. In Australia, the standard television PAL format is at 25 frames per second. A webcam with up to 30 frames per second will show normal video images. But the more frames per second you demand, the more bandwidth, memory and processing power is required.

Resolution is measured the number of pixels per inch. High quality photographs require a high resolution. But the standard for web images is a low 72 dpi. Higher resolution images will not be of any better visual quality, just slower to upload and download.

Use Myshopping.com.au to compare different webcams, camcorders and digital cameras. You can compare the prices and specifications of the different products and brands, and a wide range of reputable vendors.

The XBox 360, Not Just for Video Games



On November 22, 2005, Microsoft released the long awaited XBox 360, the next generation of its popular XBox gaming console. The XBox 360, however, goes farther than any game system that users are currently accustomed to. The XBox 360 is more like a fully functional, broadband connected entertainment gadget that appeals to gamers but is equipped to entertain the whole family.
Although smaller than the original XBox (The 360 weighs in at a mere 7.7 lbs), this version packs so many nifty features in a small package. If you also happen to own a HDTV, you will truly be able to appreciate the advanced graphics features and support for windscreen (16:9) format. Of course, the console will work on regular television as well, but the depth of the graphics will be particularly stunning on more advanced televisions. The XBOx 360 carries a ATI graphics processor and 10MB of embedded DRAM. This setup allows the XBox 360 to draw up to 500 million triangles per second for the ultimate in realistic graphics.
The XBox 360 unit also has a 12x dual layer DVD Rom drive that serves the dual purpose of playing XBox games as well as ordinary DVDs. There is also additional support for surround sound audio for the ultimate home theater experience and realistic gaming.
For game save and other media storage, you can optionally purchase a 20GB external harddrive which also serves to make the XBox 360 backwards compatible with original XBox games.
The XBox 360 goes well beyond the range of gaming and video with its built-in Ethernet port that allows users to connect via their broadband connection to XBox live (available in various flavors). XBox live will allow you to play live over the Internet, use voice and even video chat and, of course, purchase additional goodies for your XBOx. In addition to ethernet connectivity, you can optionally purchase wireless adapters that comply with the standard wireless 802.11 protocol for integration into your existing wireless network. For other data transfer tasks, such as uploading of your digital photos, digital home movies, and music, you can use the integrated USB 2.0 port. With all of these features, it is a piece of cake to stream all of your digital files.
As you can see, the XBox 360 offers a little something for everyone. Kids can enjoy the futuristic gaming capabilities (check game ratings for age appropriateness), and Mom and Dad can enjoy the file sharing, music and video streaming, and home theater features.

Playing online games.


The Internet has changed the way we do many things, it's even changed how we play Computer Games. There are several different types of Online Games:

Java/Flash Internet based Games.

Text based Games.

Online Multiplayer Games.

The Java or Flash based Internet Games are quite popular, and there are a number of Sites, such as www.miniclip.com providing Games for Free. Most people only want to play on a Game once, so they could not justify buying it.

There are hundreds of Games to choose from, and you can even play some of the classic 80's Arcade favourites! If you Register for a "my Google" Page, you can even add Pacman, ah Pacman! Just remember not to waste too long playing the Games - Pacman is extremely addictive.

To play these Online Games, you need to Download the correct plug-in for your browser, and because they have a lot of Graphics. If your Internet connection is slow, then it will probably take a long time to load. These Games are normally quite simple, and most are Single Player Games only.

Text based Games are much more simple, than the Java Games, and these are Games, that can be played in Chat rooms or Forums. These can be Role Play Games, which were extremely popular.

Online Multi player Games are the very popular Games, that you can buy in your PC stores, that allow you to compete with other people. If you wanted to play against someone before the Internet was so popular, you had to invite your friend over and play with a split screen. On some Games it was possible to have two players competing over a Network, which was quite popular.

Thanks to the Internet, now there's no need to leave your own home, you just connect to the Internet, and you can be playing Online Games against anybody that you want.

We know what you're thinking, how are you going to find people to play with ? No, of course it doesn't matter, you don't know anybody in Zanzibar! You could possibly find someone to play with from there anyway, although we don't know where it is.

You connect, or rather the Game connects to a server. The other players will also connect to this server, and so it is very easy for you to find people to play against. Wherever you are in the World, at whatever time it is, you're bound to find somebody to play against! That's the beauty of the Internet, it's Worldwide. If you just can't sleep, then you can still battle against someone, and it will be a decent hour in somebody's time zone!

Quake, Counter Strike, WarCraft, and Half Life, are the biggest titles in the Online Multiplayer Game market. A number of the instant messaging clients also come bundled with their own (all be it basic) Games, that you can play with your friends. These are quite interesting, as it's very easy to quickly play a Game with somebody, that you're currently talking to.

If you want to play Games to make money, then the Internet can still help you! There are a number of Online Gambling Sites, which could suit your needs. 

Article written by Cade Wilson.

الأربعاء، 1 مايو 2013

Pay Per Click Advertising


Advertising has gained tremendous importance in the marketing arena. Newer avenues have emerged giving much more than just the awareness factor to be looked upon. One such arena for marketing where advertising is gaining ground is Internet marketing. Many advertising techniques have come up for web based marketing or advertising projects. One of the Internets advertising techniques is termed as PPC or Pay Per Click. The Pay Per Click technique is primarily used for websites, search engines and advertising networks. 

The idea behind the PPC technique is very simple yet effective. Advertisers in order to make their advertisements seen by people offer them money to visit their website and click on a particular ad. This in turn generates revenue for the advertising companies. With search engines, Pay Per Click advertisements are usually some text ads that are strategically placed near search results; when a site visitor clicks on the advertisement, the advertiser is charged a small amount.  As the number of clicks increase, the revenue for advertising companies increases.

In today’s tough competition, the major players in this segment include Google AdWords and Yahoo search engine. As per the usage of the Pay Per Click facility, these are classified into three types of engines. These classifications are given as “keyword”, “product” and “service” engines. According to the nature of the job, these classifications differ. Normally the rates for Pay Per Click campaigns come to around $0.01 per click, but biger search engines pay upto $0.5 per click. Though it generates a small amount for the person who earns via PPC, it proves useful for people who spend around 4-5 hours on the net. 

The very heart of Pay Per Click advertising lies in the keyword search. When a prospective client searches for a particular word or phase, a list of advertisement links appear. Clicking on any one of them increases the visitor count for that particular advertisement and thus creates revenue for the advertising company. Thus, every advertising company wants to be in the first few search counts that the user sees. 

Almost the same kind of structure follows for the other two classifications. Pay Per Click is not just restricted to local advertisers. It is done on a large scale to increase the number of clicks in a single day. Nowadays many companies exist that provide Pay Per Click advertising. Judging the best out of them is a real concern for companies these days. Many of them exist only on paper and thus can be cause of fraudulent activities. You need to be extra careful while choosing a advertising agency for such advertising campaigns. For those of you who want to make some money by clicking on ads, it provides a good opportunity to earn some extra income. 

Advantages and Disadvantages of VoIP: Know Them Before Switching to VoIP Service


to VoIP Service
Today, more and more people are consciously making an effort to learn about Voice over Internet Protocol or VoIP. One thing that they all look for is whether or not VoIP can act as an alternative to the good ol telephone service, which has made such an impact in the lives. Can VoIP replace the humble telephone for good? One way to find out is to weigh the advantages and disadvantages of VoIP.

VoIP offers many advantages for you. Among them are:

1. VoIP is a whole lot cheaper compared to your normal landline telephone. With a residential VoIP plan you only need to pay about 9.95 for the most basic service up to about 39.95. For a business VoIP plan, the cost would be somewhere about 49.95 to 99.95 and comes inclusive with a separate fax number.

2. The VoIP modem (which is free) is delivered to you in only 5 to 10 days. Or you could buy it at your local store for same day service and get the VoIP provider to credit it against your bill.

3. The services which are considered as extras in your regular landline telephone service, such as Caller ID, Call Waiting, Call Forwarding, Voice Mail, 3-Way Conferencing, Repeat Dialling, and Call Block are now standard services with your VoIP. In short, you dont have to pay extra for these extra services. They come free with the package, including the most sought after service: unlimited calling, either local or long distance.

4. With VoIP service, there is no charge for any incoming calls, which cannot be said for US cellular service providers. The same also holds true for outgoing local calls, which depends on your talk plan.

5. With VoIP service in North America, local is always inclusive of US, Canada, some countries in Western Europe, parts of Asia, and parts of Latin America. For countries which are not already included, there are international plans available which cost a lot less than that offered by the standard long distance services providers. Another way is for you to make occasional calls without a plan, but for far lower charges per-minute compared to the usual long distance plans. For VoIP services in Europe, Asia and elsewhere around the globe, this also applies (more or less) in reverse.

6. With VoIP service, you dont need to have a computer. Just take your average phone cable from your VoIP modem and plug it into your regular desktop or portable phone.

7. With VoIP service, you can activate every phone jack in the house. First, disconnect your house internal phone wiring from the regular telephone service at the phone box outside (most probably on your front wall). Then, simply take the VoIP modem and plug it into any existing wall jack inside your house. However, this option is not available for those who live in apartments.

8. With VoIP service, you can choose your own virtual phone number in almost any area code that you wish for at a very low price (around 5). This way you can have friends and family dial a local number that will then ring on your phone. The drawback is that you cant make outgoing calls, as its not considered as a real line phone line.

9. With VoIP service you can have low cost 800 numbers. This way it will be free for people to call you and yet will not be too hard on your pockets. There are monthly rates fixed for you, but they vary according to the provider. Generally it could cost you about 5 for the first 100 minutes per month, and somewhere about 4.5 cents per minute beyond that.

10. Some VoIP service providers offer a service that could locate you called Find Me at other numbers that you provide, either in sequence or simultaneously, should you fail to answer your call. If you still dont answer, your call will then go to your Voice Mail which can be retrieved later.
11. And finally, the icing on the cake: You can take your home or office phone with you wherever you go. Just bring your VoIP modem with you, and when you get to your destination, plug it into any high-speed internet connection. You could be in a hotel room in the Caribbean, at your friends or relatives house in Paris or even at the airport. No matter where you are, one youre plugged in, you can make as well as receive calls on your regular phone number. Charges are based on your home location. You could be in New Zealand and if anybody were to call your office or home number in Atlanta, they would never know that youre not really there. And if you make calls, your regular caller ID still shows.
As with everything else, with advantages there are certain disadvantages, even for VoIP services:
1. If you utilise a cable connection for your Internet, your upline is 2 to 10 times slower than your downline. This means that, although you can hear crystal clear what the other person is saying, they may not necessarily hear you. This could lead them to hang up (as they dont know youre on the line), or to them telling you to call from a regular phone and to get off the speaker phone.
Even though VoIP companies insist that 256K should be sufficient for a clear signal, it does not seem to be the case. Thankfully there are ways to overcome this obstacle if you have a very knowledgeable VoIP support tech. Consult your VoIP service providers about this.
2. The quality of high-speed connections may vary, as it is dependant on many factors, including the number of other users on your cable line, or your distance from the nearest DSL booster node. This means that the VoIP quality may vary daily or during each call.

3. During your calls, when there is no one speaking, there is a silence that could lead the other person to think that the line has gone dead. This is especially true for those who have become so used to hearing a slight buzz when using a regular telephone. Instead of being bombarded with many people asking are you still on the line? you should first explain this silence that you will encounter at the very beginning of your conversation.
4. When using VoIP service, you may not be able to activate a new credit card, as the computer at the other end will claim that you are not calling from a home phone. The reason for this is yet unknown as VoIP providers have yet to answer this.
5. While conversing, you should never allow anyone to put you on silent hold, as the VoIP service may disconnect you when it doesnt hear anything. It assumes that you are no longer on the line, thus disconnecting you after a while.
6. If you have an upline signal that is not capable of relaying your call, and when you cannot get through, all that youll be hearing is a recording stating that Your call cannot be completed at this time, which can be very annoying if it happens often.
7. Sometimes, your VoIP service will just cease to work. How to solve this depends on your provider. Mostly it will take some unplugging and replugging of various connections: VoIP modem, router, cable connection, DSL connection. It all depends on your provider and the solution (and sequence) that they provide you with.
8. And finally, in what is the worst disadvantage among all, if you lose your Internet connection for whatever reason imaginable, you lose your telephone service. Should you decide to depend almost entirely on VoIP service, then you are strongly advised to have a cell phone with you at all times. This also works in your favour as you can set your VoIP service to call your cell automatically should you not answer your VoIP line.
The verdict? Commercial VoIP service is an actual telephone service, compared to the likes of messenger services (computer-based) or Skype (which insists that it is not a telephone service). Of course it has its disadvantages, it has no video (at the moment that is) and has some minor glitches. Yet these glitches can be put up with when you realize that you can save anywhere from 30 to 100 a month. These glitches may be a big issue if you plan to use VoIP for your office, but if you have a cell phone with you for back up, youd have no problems at all. You may find yourself joining the huge number of users who have gone 100% VoIP, with the intention of never again using the telephone. 

How the Internet actually works


In this article I will explain how the Internet works, all the way from what goes through the wires and how the wires across the globe connect, to how meaningful activities are performed on your computer.

Unlike other Internet articles, I won't try to explain the history behind the Internet of today it's complex enough, and like me, you probably don't care very much. I also won't be confusing you with highly technical explanations.

So, what is the Internet? To most people, it's the place to which everyone plugs in their computer and views web pages and sends e-mail. That's a very human-centric viewpoint, but if we're to truly understand the Internet, we need to be a bit more exact:

   The Internet is THE large computer network of the world that people connect to by-default, by virtue of the fact that it's the largest. And, like any computer network, there are conventions that allow it to work.

This is all it is really a very big computer network.  However, this article will go beyond explaining just the Internet, as it will also explain the 'World Wide Web'. Most people don't know the difference between the Internet and Web, but really it's quite simple: the Internet is a computer network, and the Web is a system of publishing (of websites) that sits on top of it.

Computer networks

And, what's a computer network? A computer network is just two or more of computers connected together such that they may send messages between each other. On larger networks computers are connected together in complex arrangements, where some intermediary computers have more than one connection to other computers, such that every computer can reach any other computer in the network via paths through some of those intermediary computers.

Computers aren't the only things that use networks the road and rail networks are very similar to computer networks, just those networks transport people instead of information.
Trains on a rail network operate on a certain kind of track such a convention is needed, because otherwise the network could not effectively work. Likewise, roads are designed to suit vehicles that match a kind of pattern robust vehicles of a certain size range that travel within a certain reasonable speed range. Computers in a network have conventions too, and we usually call these conventions 'protocols'.

There are many kinds of popular computer network today. The most conventional by far is the so-called 'Ethernet' network that physically connects computers together in homes, schools and offices.  However, WiFi is becoming increasingly popular for connecting together devices so that cables aren't required at all.

Connecting to the Internet

When you connect to the Internet, you're using networking technology, but things are usually a lot muddier. There's an apt phrase, "Rome wasn't built in a day" because neither was the Internet. The only reason the Internet could spring up so quickly and cheaply for people was because another kind of network already existed throughout the world the phone network!

The pre-existence of the phone network provided a medium for ordinary computers in ordinary people's homes to be connected onto the great high-tech military and research network that had been developed in years before. It just required some technological mastery in the form of 'modems'. Modems allow phone lines to be turned into a mini-network connection between a home and a special company (an 'ISP') that already is connected up to the Internet. It's like a bridge joining up the road networks on an island and the mainland the road networks become one, due to a special kind of connection between them.

Fast Internet connections that are done via '(A)DSL' and 'Cable' are no different to phone line connections really there's still a joining process of some kind going on behind the scenes. As Arthur C. Clarke once said, 'any sufficiently advanced technology is indistinguishable from magic'.

The Internet

The really amazing about the Internet isn't the technology. We've actually had big Internet-like computer networks before, and 'The Internet' existed long before normal people knew the term. The amazing thing is that such a massive computer network could exist without being built or governed in any kind of seriously organised way. The only organisation that really has a grip on the core computer network of the Internet is a US-government-backed non-profit company called 'ICANN', but nobody could claim they 'controlled' the Internet, as their mandate and activities are extremely limited.

The Internet is a testament both simultaneously due to the way technologists cooperated and by the way entrepreneurs took up the task, unmanaged, to use the conventions of the technologists to hook up regular people and businesses. The Internet didn't develop on the Microsoft Windows 'operating system' Internet technology was built around much older technical operating systems; nevertheless, the technology could be applied to ordinary computers by simply building support for the necessary networking conventions on top of Windows. It was never planned, but good foundations and a lack of bottlenecks (such as controlling bodies) often lead to unforeseen great rises like the telephone network before, or even the world-wide spread of human population and society.

What I have described so far is probably not the Internet as you or most would see it. It's unlikely you see the Internet as a democratic and uniform computer network, and to an extent, it isn't. The reason for this is that I have only explained the foundations of the system so far, and this foundation operates below the level you'd normally be aware of. On the lowest level you would be aware of, the Internet is actually more like a situation between a getter and a giver there's something you want from the Internet, so you connect up and get it. Even when you send an e-mail, you're getting the service of e-mail delivery.

Being a computer network, the Internet consists of computers however, not all computers on the Internet are created equal. Some computers are there to provide services, and some are there to consume those services. We call the providing computers 'servers' and the consuming computers 'clients'. At the theoretical level, the computers have equal status on the network, but servers are much better connected than clients and are generally put in place by companies providing some kind of commercial service. You don't pay to view a web site, but somebody pays for the server the website is located on usually the owner of the web site pays a 'web host' (a commercial company who owns the server).

Making contact

I've established how the Internet is a computer network: now I will explain how two computers that could be on other sides of the world can send messages to each other.

Imagine you were writing a letter and needed to send it to someone. If you just wrote a name on the front, it would never arrive, unless perhaps you lived in a small village. A name is rarely specific enough. Therefore, as we all know, we use addresses to contact someone, often using: the name, the house number, the road name, the town name, the county name, and sometimes, the country name. This allows sending of messages on another kind of network the postal network. When you send a letter, typically it will be passed between postal sorting offices starting from the sorting office nearest to the origin, then up to increasingly large sorting offices until it's handled by a sorting office covering regions for both the origin and the destination, then down to increasingly small sorting offices until it's at the sorting office nearest the destination and then it's delivered.

In our postal situation, there are two key factors at work a form of addressing that 'homes in' on the destination location, and a form of message delivery that 'broadens out' then 'narrows in'. Computers are more organised, but they actually effectively do exactly the same thing.

Each computer on the Internet is given an address (a so-called 'IP address'), and this address 'homes in' on their location on the Internet. The 'homing in' isn't done strictly geographically, but rather in terms of the connection-relationship between the smaller computer networks within the Internet. For the real world, being a neighbour is geographical, but on a computer network, being a neighbour is having a direct network connection.

Like the postal network with its sorting offices, computer networks usually have connections to a few other computer networks. A computer network will send the message to a larger network (a network that is more likely to recognise at least some part of the address). This process of 'broadening out' continues until the message is being handled by a network that is 'over' the destination, and then the 'narrowing in' process will occur.

An example 'IP address' is '69.60.115.116'. They are just series of digit groups where the digit groups towards the right are increasingly local. Each digit group is a number between 0 and 255. This is just an approximation, but you could think of this address meaning:
  • A computer 116
  • in a small neighbourhood 115
  • in a larger neighbourhood 60
  • controlled by an ISP 69
  • (on the Internet)
The small neighbourhood, the larger neighbourhood, the ISP, and the Internet, could all be consider computer networks in their own right. Therefore, for a message to the same 'larger neighbourhood', the message would be passed up towards one of those intermediary computers in the larger neighbourhood and then back down to the correct smaller neighbourhood, and then to the correct computer.

Getting the message across

Now that we are able to deliver messages the hard part is over. All we need to do is to put stuff in our messages in a certain way such that it makes sense at the other end.

Letters we send in the real world always have stuff in common they are written on paper and in a language understood by both sender and receiver. I've discussed before how conventions are important for networks to operate, and this important concept remains true for our messages.

All parts of the Internet transfer messages written in things called 'Packets', and the layout and contents of those 'packets' are done according to the 'Internet Protocol' (IP). You don't need to know these terms, but you do need to know that these simple messages are error prone and simplistic.
You can think of 'packets' as the Internet equivalence of a sentence for an ongoing conversation, there would be many of them sent in both directions of communication.

Getting the true message across

All those who've played 'Chinese whispers' will know how messed up ('corrupted') messages can get when they are sent between many agents to get from their origin to their destination. Computer networks aren't as bad as that, but things do go wrong, and it's necessary to be able to automatically detect and correct problems when they do.

Imagine you're trying to correct spelling errors in a letter. It's usually easy to do because there are far fewer words than there are possible word-length combinations of letters. You can see when letter combinations don't spell out words ('errors'), and then easily guess what the correct word should have been.
   It reely does worke.

Errors in messages on the Internet are corrected in a very similar way. The messages that are sent are simply made longer than they need to be, and the extra space is used to "sum up" the message so to speak if the "summing up" doesn't match the message an error has been found and the message will need to be resent.
In actual fact, it is often possible to logically estimate with reasonable accuracy what was wrong with a message without requiring resending.

Error detection and correction can never be perfect, as the message and "summing up" part could be coincidently messed-up so that they falsely indicate nothing went wrong. The theory is based off storing a big enough "summing up" part so that this unfortunate possibility is so unlikely that it can be safely ignored.

Reliable message transfer on the Internet is done via 'TCP'. You may have heard the term 'TCP/IP': this is just the normal combination of 'IP' and 'TCP', and is used for almost all Internet communication. IP is fundamental to the Internet, but TCP is not there are in fact other 'protocols' that may be used that I won't be covering.

Names, not numbers

When most people think of an 'Internet Address' they think of something like 'www.ocportal.com' rather than '69.60.115.116'. People relate to names with greater ease than numbers, so special computers that humans need to access are typically assigned names ('domain names') using a system known as 'DNS' (the 'domain name system').

All Internet communication is still done using IP addresses (recall '69.60.115.116' is an IP address). The 'domain names' are therefore translated to IP addresses behind the scenes, before the main communication starts.

At the core, the process of looking up a domain name is quite simple it's a process of 'homing in' by moving leftwards through the name, following an interrogation path. This is best shown by example 'www.ocportal.com' would be looked up as follows:

  • Every computer on the Internet knows how to contact the computers (the 'root' 'DNS servers') responsible for things like 'com', 'org', 'net' and 'uk'. There are a few such computers and one is contacted at random. The DNS server computer is asked if they know 'www.ocportal.com' and will respond saying they know which server computer is responsible for 'com'.
  • The 'com' server computer is asked it knows 'www.ocportal.com' and will respond saying they know which server computer is responsible for 'ocportal.com'.
  • 'The 'ocportal.com' server computer is asked if it knows 'www.ocportal.com' and will respond saying that it knows the corresponding server computer to be '69.60.115.116'.

Note that there is a difference between a server computer being 'responsible' for a domain name and the domain name actually corresponding to that computer. For example, the 'ocportal.com' responsible DNS server might not necessarily be the same server as 'ocportal.com' itself.

As certain domain names, or parts of domain names, are very commonly used, computers will remember results to avoid doing a full interrogation for every name they need to lookup. In fact, I have simplified the process considerably in my example because the looking-up computer does not actually perform the full search itself. If all computers on the Internet did full searches it would overload the 'root DNS servers', as well as the DNS servers responsible for names like 'com'. Instead, the looking up computer would ask it's own special 'local DNS server', which might remember a result of a partial result, or might solicit help (full, or partial) from it's own 'local DNS server', and so on until, in a worst case scenario, the process has to be completed in full.

Domain names are allocated by the person wanting them registering the domain name with an agent (a 'registrar') of the organisation responsible for the furthest right-hand part of the domain name. At the time of writing a company named 'VeriSign' (of which 'Network Solutions' is a subsidiary) is responsible for things like 'com' and 'net'. There are an uncountable number of registrars operating for VeriSign, and most domain purchasers are likely not aware of the chain of responsibility present instead, they just get the domains they want from the agent, and deal solely with that agent and their web host (who are often the same company). Domains are never purchased, but rather rented and exclusively renewable for a period a bit longer than the rental period.

Meaningful dialogue

I've fully covered the essence of how messages are delivered over the Internet, but so far these messages are completely raw and meaningless. Before meaningful communication can occur we need to layer on yet another protocol (recall IP and TCP protocols are already layered over our physical network).

There are many protocols that work on the communications already established, including:

  • HTTP for web pages, typically read in web browser software
  • POP3 for reading e-mail in e-mail software, with it stored on a user's own computer
  • IMAP4 for reading e-mail in e-mail software, with it archived on the receiving server
  • SMTP for sending e-mail from e-mail software
  • FTP for uploading and downloading files (sometimes via a web browser, although using special FTP software is better)
  • ICMP for 'pinging', amongst other things (a 'ping' is the Internet equivalent to shouting out a 'are you there')
  • Telnet for logging into another computer across the Internet and typing in commands for it (the old operating systems that the Internet developed around are heavily based on the typing in of commands rather than just using a mouse don't expect to be able to telnet to a Windows computer)
  • MSN Messenger this is just one example of many protocols that aren't really standard and shared conventions, but rather ones designed by a single software manufacturer wholly for the purposes of their own software

I'm not going to go into the details of any of these protocols because it's not really relevant unless you actually need to know it.

The information transferred via a protocol is usually a request for something, or a response for something requested. For example, with HTTP, a client computer requests a certain web page from a server via HTTP and then the web server, basically, responds with the file embedded within HTTP.

Each of these protocols operates on more or more so-called 'ports', and it is these 'ports' that allow the computers to know which protocol to use. For example, a web server (special computer software running on a server computer that serves out web pages) uses a port of number '80', and hence when the server receives messages on that port it passes them to the web server software which naturally knows that they'll be written in HTTP.
For a client computer it's simpler it knows that a response to a message it sent will be in the same protocol it initially used. When the messages are sent back and forth the server computer and client computer typically set up a so-called 'stream' (a marked conversation) between them. They are then able to associate messages to the stream according to their origin address and port number.

The World Wide Web

I've explained how the Internet works, but not yet how the 'World Wide Web' (the 'web') works. The web is the publishing system that most people don't realise is distinguishable from the Internet itself.
The Internet uses IP addresses (often found via domain names) to identify resources, but the web has to have something more sophisticated as it would be silly if every single page on the Internet had to have it's own 'domain name'. The web uses 'URLs' (uniform resource locators), and I'm sure you know about these as nowadays they are printed all over the place in the real world (albeit, usually only in short-hand).

A typical URL looks like this:
   <protocol>://<domain-name_OR_ip-address>/<resource_identifier>
For example:
   http://www.ocportal.com/index.php
That said that's not really a full URL, because occasionally URLs can be much more complex. For example:
   <protocol>://<user>:<password>@<domain/ip>:<port>/<resource_identifier>
You can ignore the more complex example, because it's not really relevant for the purposes of this article.

HTTP is the core protocol for the web. This is why URLs usually start 'http://'. Web browsers almost always also support FTP, which is why some URLs may start 'ftp://'.

Typically the 'resource identifier' is simply a file on the server computer. For example, 'mywebsite/index.html' would be a file on the server computer of the same path, stored underneath a special directory. On Windows the "" symbol is used to write out directory names, but as the web wasn't invented for Windows, the convention of the older operating systems is used.

We now have three kinds of 'Internet Address', in order of increasing sophistication:
  • IP addresses
  • Domain names
  • URLs

If a URL were put into web browser software by a prospective reader then the web browser would send out an appropriate request (usually, with the HTTP protocol being appropriate) to the server computer identified by the URL. The server computer would then respond and typically the web browser would end up with a file. The web browser would then interpret the file for display, much like any software running on a computer would interpret the files it understands. For the HTTP protocol, the web browser knows what to interpret the file as because the HTTP protocol uses something called a 'MIME type' to identify each kind of resource the server can send out. If the web server computer is just sending out an on-disk file then the web server computer works out the MIME type from the file extension (such as '.html') of the file.

An 'HTML' file is the kind of file that defines a web page. It's written in plain text, and basically mixes information showing show to display a document along with the document itself. If you're curious, try using the "View page source" function of your web browser when viewing a web page, and you'll see a mix of portions of normal human text and short text between '<' and '>' symbols. The former is the document contents and the latter are the display instructions.
In newer versions of HTML there's a split between 'structuring' a document and 'displaying' a structure in this case, another special technology named 'CSS' is added to the mix.

I've explained how typical web pages are just files on the disk of a server computer. Increasingly, things are slightly less direct. When you visit something like eBay, your web-mail, or an ocPortal-powered website, you aren't just reading files. You're actually interacting with computer software, and the web pages you receive are generated anew by that software every time a request is made. These kinds of systems are known as 'web applications' and are increasingly replacing the need to install software on your own computer (because it's so much easier just to use a web browser to access a web application on a server computer).

Whispering across the globe

The problem with sending messages around the world using protocols such as HTTP, built on well-understood standard protocols, potentially between 100's of computers, is that it's hardly safe when those messages contain passwords and credit card details.

There are in fact three main security problems with just using common Internet technologies for sensitive communication. These problems are that any of the 'middleman' computers between source and destination could be:
listening in (for passwords, for example)
  • altering the conversation (inserting instructions into banking requests to take money out of bank accounts, for example)
  • hijacking requests (pretending to be the bank, for example)
To solve these three problems we need to encode data so that:
  • it's encrypted
  • it's only encryptable by the sender (i.e. Tampering becomes impossible, because they don't know how to encrypt new data to tack on)
  • it's provable that the engaging client computer really is the correct client computer and that the responding server computer really is the correct server computer

This is all done using something called 'TLS' (formerly named 'SSL'). I won't explain exactly how it's done, but the basis is that there's a way of encrypting, and the receiver can identify whether the sender did the encrypting itself without actually knowing how the sender did it. It's done using some mathematical trickery.

Conclusion

I've explained:
  • how computers can be connected together, even under non-ideal conditions (such as not being physically connected, or only with having a phone line as a connection to the world)
  • how an Internet can be built such that all the computers on it can contact each other
  • how messages can be sent between computers on the Internet
  • how messages can encode requests and responses that translate to meaningful human applications
  • how human-understandable URLs, built upon human understandable domain names, allow the world wide web to function
  • how files can encode web pages
  • how the Internet can be made safe and secure

I hope you've learnt a lot from this article. The Internet is big and it's complex, with so many technologies that very few people can understand all of them fully. It's amazing how the chaotic and unplanned amalgamation of technologies that allow the Internet to function has, by the collective and non-organised efforts of the masses, allowed such an amazing single and coherent system of information sharing and global communication to evolve.
 

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