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policedemil

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Thank you! This is starting to make a lot more sense! I guess what's still confusing to me has to do with the seriality (continuity?) of the process vs the OSI model, which seems like there are more discrete stages.

Does each stage of the model need to complete for the whole packet before moving on to the next stage? For example, does A/D conversion take place until all of the packet information is converted, then the whole binary blob is enframed as a header and a packet... then we filter for MAC address and move on up the stack in discrete and consecutive stages? Or are the voltages read off the line and once there is enough information to construct the header, compare it, then choose to continue reading the rest from the line or stop the A/D conversion because it is just a waste of energy? The latter makes a lot more sense to me.

EDIT: words

Great article! A lot of this is way beyond me, but I'm generally interested in the process of how a NIC filters based on MAC addresses.

I'm in the humanities and certain scholars working with culture and technology love to make a huge deal about data leakage and how intertwined we all are precisely because you can put a NIC in promiscuous mode and cap packets that weren't meant for you. The whole point is that because your NIC is constantly receiving data meant for others (i.e. because it's filtering the MAC addresses), something like privacy on networks is always problematic. I've always found the whole point somewhat overstated.

So, could anyone explain real quick the process of how a NIC decides whether a packet/frame is actually bound for it or link some good resources? For example, does the NIC automatically store the frame/packet in a buffer, then read the header, and then decide to discard? Or can it read the header before storing the rest of the frame? How much has been read at the point the NIC decides to drop it or move it up the stack? Reading all of every packet seems improbable to me because if it were the case, laptop 1 (awake but not downloading anything) would experience significant battery drain due to constantly filtering network traffic that was meant for laptop 2. I'm not sure that really maps to my experience. Also, I assume there are also differences for LAN vs WiFi?

Any help on the matter would be greatly appreciated! I've tried google diving on this question many times before and it's really hard to find much on it.