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Die another Day? Or How crashed the Internet

When pop star Madonna took to the stage at Academy in 2001 for a rare appearance she made Internet history and caused more that a little Internet misery. Her concert performance was webcast; that is it was broadcast real time over the Internet. A record-breaking audience of 9 million tuned in, and that’s where the trouble started...

The Internet’s early The Internet gets into career the groove The Internet started its career as a way of The problem with live pop videos, like a sending text messages between military Madonna concert, is that it’s no use if the bases. What was important was that the last part of the song arrives first, or you message got through, even if parts of the have to wait half an hour for the middle network were damaged say, during times chorus to turn up, or the last word in a of war. The vision was to build a sentence vanishes. It needs to all arrive| communications system that could not in real time. After all, that is how it’s being fail; even if individual computers did, sung. So to make web casting work there the Internet would never crash. The text needs to be something different, a new way messages were split up into tiny packets of sending the packets. It needs to be fast of information and each of these was sent and it needs to deal with lots more packets with an address and their position in the as video images carry a gigantic amount of message over the wire. Going via a series data. The solution is to add something new of computer links it reached its destination to the Internet, called an overlay network. a bit like someone sending a car home bit This sits on top of the normal wiring but by bit through the post and then rebuilding behaves very differently. it. Because it’s split up the different bits can go by different routes. The Internet turns rock and roll rebel Express yourself So the new real time transmission protocol (but be polite please) gets a bit rock and roll, and stops being To send all these bits of information a set of quite so polite. It takes the packets and protocols (ways of communicating between throws them quickly onto the Internet. the computers making up the Internet) If the receiver catches them, fine. If it were devised. When passing on a packet doesn’t, then so what? The sender is too of information the sending machine first busy to check like in the old days. It has asks the receiving machine if it is both to keep up with the music! If the packets there and ready. If it replies yes then the are kept small, an odd one lost won’t be packet is sent. Then, being a polite missed. This overlay network called the protocol, the sender asks the receiver if the Mbone, lets people tune into the packets all arrived safely. This way, with the transmissions like a TV station. All these right address, the packets can find the best packages are being thrown around and way to go from A to B. If on the way some if you want to you can join in and pick of the links in the chain are damaged and them up. don’t reply, the messages can be sent by a different route. Similarly if some of the packets gets lost in transit between links It ’s like someone and need to be resent, or packets are sending a car bit delayed in being sent because they have by bit through the to go by a round about route, the protocol post… different bits can work round it. It’s just a of time can go by different before all the packets arrive at the final routes destination and can be put back in order. With text the time taken to get there doesn’t really matter that much.

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Crazy for you Wh o’s that girl? unnoticeably compress videos down to The Madonna webcast was one of the first Viewers suffered as the pictures and sound small numbers of packets, and intelligent real tests of this new type of approach. cut in and out. Pictures froze then jumped. algorithms have been developed to reroute She had millions of eager fans, but it was Packets arrived well after their use by date, data effectively round blocks. We can also early days for the technology. Most people meaning earlier images had been shown now combine the information flowing to the watching had slow dial-up modems rather missing bits and looking fuzzy. You couldn’t viewers with information coming back from than broadband. Also the number of even recognise Madonna on stage. Some them so allowing interactive webcasts. With computers making up the links in the researchers found that packets had, for the advent of digital television this service is Internet were small and of limited power. example, passed over seven different now in our homes and not just on our PC’s. As more and more people tuned in to networks to reach a PC in a hotel just four watch, more and more packets needed miles away. The packets had taken the Living in a material to be sent and more and more of the links scenic route round the world, and arrived world started to clog up. Like dozens of cars all too late for the party. It wasn’t only the It’s because of thousands of scientists racing to get through a tunnel there were Madonna fans who suffered. The broadcast working on new and improved technology traffic jams. Packets that couldn’t get made use of the underlying wiring of the and software that we can now watch as through tried to find other routes to their Internet and it had filled up with millions the housemate’s antics stream live from the destination … which also ended up of frantic Madonna packets. Anyone else Big Brother house, vote from our armchair blocked. If they did finally arrive they trying to use the Internet at the time for our favourite talent show contestant couldn’t get through onto the viewers PC discovered that it had virtually ground to a or ‘press red’ and listen to the director’s as the connection was slow, and if they did, halt and was useless. Madonna’s fans had commentary as we watch our favourite very many were too late to be of any use. effectively crashed the Internet! TV show. Like water and electricity the It was Internet gridlock. Internet is now an accepted part of our Webcasts in Vogue lives. However, as we come up with even Today’s webcasts have moved on more popular TV shows and concerts, Like dozens of cars tremendously using the lessons learned strive to improve the quality of sound and all racing to get from the early days of the Madonna pictures, more people upgrade to through a tunnel Internet crash. Today video is very much a broadband and more and more video there were traffic part of the Internet’s day-to-day duties: the information floods the Internet … will the jams. It was Internet speed of the computer links of the Internet Internet Die another Day? gridlock. and their processing power has increased massively; more homes have broadband so the packets can get to your PC faster; satellite uplinks now allow the network to identify where the traffic jams are and route the data up and over them; extra links are put into the Internet to switch on at busy times; there are now techniques to

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