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I am currently learning about Wireless networks and I have read that Wireless Networks are Half-Duplex and all devices receive the frames sent by other devices just like with Ethernet hubs.

Does this mean that if we had 2 devices like a smartphone and a laptop connected to a Wireless router, for example enter image description here

The smartphone would receive all the data that the Laptop sends to the internet and vice versa?

In such case, shouldn't only one of the 2 devices be able to communicate on the Internet? If the Laptop kept receiving or transmitting data to the Internet, would the Smartphone also be able to communicate with the Internet at the same time?

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all devices receive the frames sent by other devices

That is not exactly right. Access points act more like switches, forwarding frames to the destination, whether is is wired or wireless.

Because the media is radio, all (nearby) stations do "hear" the sender, but just detect the presence of the transmission to avoid collisions. In other words, they don't decode the signal.

Two devices "communicate at the same time" by simply taking turns sending packets. So in reality, only one station is transmitting at a time. But it happens so fast, it appears to be simultaneous to our slow brains.

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  • Also, in an "enterprise" setup, every station could have a different encryption key, so other stations can hear their traffic, but not understand it. (simple/home networks rarely go to that complexity) In "infrastructure mode" (where there's an AP), stations talk to the AP, not each other. (an "adhoc" network has no AP, and stations talk to each other.)
    – Ricky
    Dec 22, 2022 at 18:39
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What you may want to know is about Medium Access Control Sublayer protocols.

If two devices use the medium at the same time, this will cause a collision, and you will get wrong dataframes. Dealing with errors is a data link layer stuff.

Data link provides in a computer network communication the reliability related to error control and message consistency. So assume that if a dataframe sent is wrong or lost, it will know. Therefore, assuming we can know if some dataframe was correctly delivered or not, generally speaking we can "probe" the communication medium like this:

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