EXPLORING THE INTERNET, Article 2: How Information Travels Across the Internet
James Eastman, M.S. Computer Science
10/31/2006
Logging on to the Internet, viewing web pages, working with email and other media, has become second nature for the modern office worker. However, the process of sending and receiving that information over the Internet is remarkably complex.
When you send information across the Internet the Transmission Control Protocol (TCP) first breaks it into packets. Those packets are then sent to your local network or Internet Service Provider (ISP). From there, the packets travel through many levels of networks, computers and communication lines before they reach their final destination. A variety of hardware processes the information and sends it in the right direction. Five of the most important pieces of hardware that handle Internet traffic are hubs, bridges, gateways, repeaters and routers. Let’s take a quick look at what each one does.
Hubs link groups of computers to one another and let computers communicate with each other.
Bridges link local area networks (LANS) with one another. They let data intended for other networks go there, and keep local data inside its own network.
Gateways do a similar job as Bridges, but they also translate data from one kind of a network to another.
Repeaters amplify data in intervals so that data traveling great distances doesn’t weaken.
Routers play a key role in managing Internet traffic. They insure that the packets of data always arrive at the proper destination.
Data moving over the Internet can travel via many different routes and experience delays or corruptions depending on the conditions in the network. The speed at which data travels over the Internet varies and is constantly increasing as technology evolves. Scientists are racing to move massive amounts of data at every increasing speeds.
“Internet2” is a second generation network serving universities and research institutes. In 2004 scientists at the California Institute of Technology (Caltech) and the European Organization for Nuclear Research (CERN) set a new land-speed record using Internet2. The team transferred 859 gigabytes of data in less than 17 minutes. It did so at a rate of 6.63 gigabits per second between the CERN facility in Geneva, Switzerland, and Caltech in Pasadena, California, a distance of more than 15,766 kilometers, or approximately 9,800 miles. Wouldn’t it be great if our home DLS and cable connections had speeds like this?
