NICs in relation to OSI

TattooMattTattooMatt Member Posts: 18 ■□□□□□□□□□
I've seen some conflicting info on NICs relation to the OSI model. I've seen some sources mapping NICs to layer 2 and some others map it to layer 1.

I realize they operate at both layers. Am I missing something? How do I answer this question if it's on the exam. icon_rolleyes.gif
How many do I have now donut lady!?!?!


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    janmikejanmike Member Posts: 3,076
    Here's a previous post on this subject.

    Best of luck!
    "It doesn't matter, it's in the past!"--Rafiki
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    TattooMattTattooMatt Member Posts: 18 ■□□□□□□□□□
    Thanks. I think some of the questions I've been coming across regarding this are either: A. Vague B. Involve a keyword (like interface).

    Thanks again. icon_thumright.gif
    How many do I have now donut lady!?!?!
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    Fu LoserFu Loser Member Posts: 123
    Question #9 on the N+ practice exam has the NIC on the physical layer. I see a lot of layer 2 talk in the link above my post. Inless im reading the post in the link wrong, I take it the question on the practice exam is wrong? icon_confused.gif:
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    WebmasterWebmaster Admin Posts: 10,292 Admin
    Please don't post the same thing twice...

    No the question is not wrong. It's ambigous though... and it might be better to set Data Link also as a correct answer, but as I wrote in the explanation:
    The drivers are defined at the Layer 2 (Data Link) and the NIC itself at Layer 1 (Physical layer.) The Data Link layer communicates with the NIC and allows it to access the physical media, but the NIC itself (the pins, the BNC, RJ45 connectors etc) and how it handles the raw bit stream is defined at Layer 1.
    I know it sounds kind of contradictive (with the older post), I'll get back to that after the following:
    I realize they operate at both layers. Am I missing something? How do I answer this question if it's on the exam.
    I'd go for Physical, and select the Data Link layer, (or better MAC sub-layer) if it would allow for two options.

    The problem isn't the answer(s) but the question itself. Obviously the NIC is involved in tasks on both the Physical and the Data Link layer, but the NIC itself can't do anything without the help of software, the drivers and the networking client software for example. Without the software the NIC is basically as dumb as a hub (layer 1, puts signals on cable, physical characteristics of interface), but with the drivers and the software it becomes smarter and can act like a switch (layer 2, MAC layer addressing...), and if you combine two of them they can route (layer 3).

    The above is not meant to clear up any confusion, just pointing out why the confusion exists. icon_wink.gif
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    Fu LoserFu Loser Member Posts: 123
    When I as taught, the teacher did a good job of seperating the two based on the contex. I always assumed layer 1 inless calling for more then just simple 1 and 0's.

    This is how I viewed the question when I first saw it, but when I saw a post regarding that question, I then started thinking to much and confused myself.

    Thanks for the explo/info Webmastersicon_exclaim.gif
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    keenonkeenon Member Posts: 1,922 ■■■■□□□□□□
    anytime you see and answer for NIC's osi layer it will be physical layer b/c of the pin specs don't ask why it just is as it was made clear to me .. it was changed from the previous version of the test icon_scratch.gif
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