How Does Data Travel the Internet?

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How Does Data Travel the Internet?

• Presented by
• Dixie Fjeld

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Starting the Data Travel

• To understand compare this journey to an
  interstate car trip.
• A personal computer is connected to either a LAN
  (local area network) or by a modem connected
  through a phone, cable, or DSL to a network.
• The browser asks the web server to retrieve
  information and sent it back to the browser.
• Netscape Navigator
• Windows Internet Explorer

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Process of Data Travel

• Once connected on your network, your computer
  will make a connection to another network.
• If distance is far enough, your LAN may need to
  go through a router.
• Router a device that connects networks, which
  is a switching device that routes Internet
  messages to their destination.
• Purpose of a router determines available
  connections and chooses best path for travel to
  continue.

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Continued Travels

• Some networks might be grouped into a mid-level
  network called a WAN (wide area network).
• A WAN covers a large geographic area and can make
  connections through orbiting satellites.
• Router may also send information directly by
  using high-speed phone lines, fiber-optic
  connections, or microwave links.

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Traveling Continues

• As the request passes from network to network, a
  set of protocols creates packets.
• Protocols are the rules or standards that define
  how the Internet works.
• Packets contain the data itself as well as the
  addresses, error checking, and other information
  needed to make sure the request arrives intact at
  the destination. Each message or file is
  disassembled and placed into packets for routing
  over the Internet.

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Travels Continuing

• If destination isnt on the same WAN as your host
  network, the router sends the request to a
  network access point (NAP)
• NAP (network access point) where regional
  backbones connect to national backbone networks
  (like the freeway on-ramp)
• Backbones a collection of networks that link
  extremely powerful supercomputers (like the
  freeway)

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Still Traveling - Getting Slower

• Through the process, your request might pass
  through repeaters, hubs, bridges, and gateways.
• Repeaters amplify or refresh the stream of
  data, which deteriorates the farther it travels
  from your PC. These allow the data signals to
  reach more remote PCs.

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Getting Tired of TravelingHelp!

• Hubs in a LAN, a hub connects several
  workstations and enables them to exchange data.
• Bridges link LANs so that data from one network
  can pass through another network on its way to
  other LANs.
• Gateways they translate data between one type
  of network and another.

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Final Destination

• When the request reaches its destination, the
  packets of data, addresses, and error-corrections
  are read. The remote computer then takes the
  appropriate action, such as running a program,
  sending data back to your PC, or posting a
  message on the Internet.

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Data Travel Over the Internet

A router determines the best path to get the
request moving on the right track
Protocols - rules

WAN covers a large geographic location and can
incorporate connections through orbiting
satellites.
Repeaters amplify and refresh data

Hubs link groups of networks that all can talk
to any other networks
Packets contain the data itself as well as
addresses, error checking, and other info needed
to make sure the request arrives intact at the
destination.
LAN Local Area Network connects to other
networks

Bridges link LANS so data can pass from network
to network
NAP- regional backbones connect - supercomputers
Gateways similar to bridges translate data
between one type of network and another e.g.
Intel based to a Unix
system.
You at your computer
When the request reaches its destination, the
packets of data, addresses, and error-correction
are read and then sends the data back to your PC.
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Sources of Information

• www.prenhall.com/pfaffenberger (2002).
• Pfaffenberger, Bryan.(2004). Computers in your
  Future. New Jersey Prentice-Hall.
• Long, Larry and Long, Nancy. (2004) Computers
  Information Technology in Perspective. New
  Jersey Prentice-Hall.

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Summary There is more to sending a
message or researching information than you
thought!
Thanks!