Computer science from A to Z
I is for Internet
You want to wish a happy birthday to your old friend who has retired to Bora Bora?
You can contact him via instant messaging software and the Internet, the network of networks, which links computers all over the world.
But how do all the data transmitted over the Internet arrive safely at their intended destination?
The message must first be broken down into small data packets that are easy to send and receive without error. At the beginning of each packet, a tag indicates its sender, its receiver and various technical details.
These packets are sent one after the other over the Internet. Each one passes successively through several electronic relays which analyse it to determine its destination and decide on the most appropriate route. It is important to know how to avoid congestion in the network and adapt when a relay suddenly stops functioning.
After various forwarding operations, the packets arrive at their destination. All that remains is to check that no errors have slipped in, then reassemble the packets in the right order. By the way, how do you say "happy birthday" in Tahitian?