ISO is an organization. OSI is a model.
Edit: there are also definitely more than four “layers” (standard handoff points).
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Physical involves the media and transmission format (e.g. EMF, waveform, etc)
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data link involves multiplexing and addressing on the local segment
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Network involves beyond-segment addressing
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Transport involves standard endpoint communication methods (tcp/udp)
Are you implying this is where everything ends?
What about application level multiplexing (sockets)?










How many saw the other one?