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Hi i want to know exactly what network card does? actually where can i find the spec which explains the scope and functionality of the card on network? who creates ...
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    Question Need help on Ethernet card?


    Hi i want to know exactly what network card does? actually where can i find the spec which explains the scope and functionality of the card on network? who creates and manages these specs? My core interest is in knowing what happens after the data arrives at the serial port on which network card is attached and before it is delivered on the medium. Does network card detects the IP? Who decides whether it is intended to the system or not? if network card can determine whether the packet belongs to the system or not?, up to what level it process the packet? Who re assembles the packets that come in a series?

    Thanks in advance guys.

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    Linux Engineer GNU-Fan's Avatar
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    Debian GNU/Linux -- You know you want it.

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    Thumbs up Thank you so much

    Hi Thank you so much for referring to that thread on wikipedia. I have googled on wikipedia but some how missed this thread.

    ok please confirm my understanding. Ethernet card is only interested and bothered about MAC address. if the MAC address matches even though the IP does not match it interrupt the processor and passes the packets to it. It is the software layer(not sure of OSI layers) or the layer above the physical layer which is really bothered about the IP or any other information in that packets.

    And also no body can mess around(fool) with the MAC address but they can with IP.

    Thanking you so much.

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    can some body confirm pls?

    can somebody confirm my understanding pls? Really this helps me a lot. please.

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    The data link layer is usually dealt with by the hardware (or it's firmware).
    But this is not a necessity. How much the processor needs to do is determined by the particular driver.

    Also, there are drivers/cards around which can use arbitrary MACs.
    So the possibility is there.
    Debian GNU/Linux -- You know you want it.

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    Question doubts not yet cleared

    Hi I understood what you are saying. My point is to confirm that IP is not related to physical layer. Now i understood that MAC also can be duplicated. I mean can be faked. But my point is as long as the MAC contains the address it reached the packet will be allowed into the system for further processing. Is this right?

    One more small question who adds the MAC addresses to the data packet. Is it the LAN card driver or network card? no need to be always true. I am asking in general.

    or
    MAC addresses will be added by the time the packet comes to the driver from OS?

    as far as i know the driver and network card does not do anything other than converting binary data into the form that can be transfered over the network media.

    Am i right? Pls don't mind for asking so many questions.

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    Sounds like you're looking for some understanding of the OSI.
    Jay

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    No No Not exactly. I am not interested in OSI. I am not really interested what layers are there and what they does.

    by now I am very clear that TCP/IP is done by software(might be OS) and also TCP packets are created by the software itself. The LAN card driver transports the packets to LAN card and it converts them to the form that can be traveled over the network media.

    My only doubt is who adds the MAC headers to the Data Packet. IS it hardware or software(including OS)? I think this makes my question clear?

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    Administrator jayd512's Avatar
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    lol... haven't dug that far into a question since studying for an exam!
    You're not, are you?

    I am not interested in OSI. I am not really interested what layers are there and what they does.
    The layers that you're asking about are the OSI.
    If you look at the OSI, you will find complete understanding of the roles played by both the hardware and software layers.
    It all plays into how the TCP/IP stack interacts with the hardware interface... no matter if it's a NIC, Token Ring or a Serial Port.

    Read up on the OSI... it explains everything that you happen to be asking about far better than can be explained on a forum!
    Jay

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