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Data transmission

  1. Oct 21, 2004 #1


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    I was asked a weird question, K12 level, but interesting...

    How is the data transferred through two computers, and how (and what) is it converted to the data again? Please send me some resources about it, or suggest your own ideas. I didn't like mine, so decided to ask in the forum.

  2. jcsd
  3. Oct 21, 2004 #2
    simple, data is broken down into 1s and 0s, the data is compiled by the cpu/motherboard/ram combo, and then stored on the HDD as the compiled file, and vise versa
  4. Oct 22, 2004 #3


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    Thank you for your reply.

    Another question comes now, what kind of transmittance options are possible between two computers? I know that there are several ways to do it, for example, e-mail messaging, direct cable connection, network connection, and so on. I've also told that a relatively new kind of transmittance involves the use of IR waves, better known as bluetooth, if I'm not wrong.

    Let's look into these types of transmissions. I am nearly sure all of these use the system you mentiones, that is, 1s and 0s compiled or decompiled, and of course derived from electrical currents or amperes, etc.
  5. Oct 22, 2004 #4
    Its not as simple as that IMHO

    Within Networking we look at the OSI model... which is comprised of 7 layers:
    Data Link

    The information presented by the application layer is encapsulated at each layer with more and more header information. Each layer is responsable for different jobs, (for example transport managers network layer connections, and provides relieable packet delivery)

    So the end result is a stream of differeing voltages on the wire in the form of frames, frames are a defined size and bits in the frames represent different checksums addressing info and where the data portion will be....

    To port this over to Bluetooth or any other protocol for that matter you need to change the physical layer behaviour...

    this is the power behind using hierarcial designs for systems...


    All this is done even before the data has hit the main cpu, by the network card.

    You would say a file would reside above the appilication layer, and a transfer protcol like FTP would reside at the application layer...
    Last edited: Oct 22, 2004
  6. Oct 22, 2004 #5


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    Thank you both for your interest. The second one was a such detailed and comprehensive answer. The first is also okay, I think it is enough for him to understand the basics involved here. I'll inform the person asked this question with the information you two gave.

    Take care
  7. Oct 22, 2004 #6
    LOL, I really didn't feel like spending more than 2 minutes on a post, becuase I posted that at school. :shy:
  8. Nov 8, 2004 #7
    Are you referring to the transmission media (physical layer) or to application programs (application layer)?
    Let's sort it out. In the physical layer we have various transmission media: Copper wires (like coaxial cables or coax, unshielded twisted pair or UTP, shielded twisted pair, etc.), optical fibers, infrared light, radio waves (combined with satellites), microwaves (also used in cellular phones), and even beams of visible light. The signals in these media could be either digital (1s and 0s) or analogue (continuous waveforms) that can be translated to digital.
    Regarding the data layer (framing) you could connect to a Local Area Network (Ethernet, FDDI, ATM, Token Ring, etc), a Metropolitan Area Network, or to a Wide Area Network/WAN. The Internet is a combination of these networks.
    As regards to the application layer, there can be various protocols of communication, that is, how two computers agree on the meaning of the data being exchanged (including e-mail, IRC, File Transfer Protocol, and so on).
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