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Comment by lmm

10 years ago

Switches aren't supposed to exist in the OSI model at all, which makes it of questionable usefulness today - when was the last time you used a purely-hubbed network?

I am not understanding the point you are trying to make.

OSI is just a model and it is not limited to end stations. What gives you that impression?

Conceptually and virtually switches most certainly do exist in the OSI model.

For all practical purposes a switch can be thought of as a multiport bridge. And as such it exists at Layer 1 and Layer 2.

  • > OSI is just a model and it is not limited to end stations. What gives you that impression?

    I didn't say anything about end stations? The point is that a switch is inherently a violation of OSI layering (it uses layer-3 information to make layer-2 decisions), which given that practically all modern networks are switched, suggests that the 7-layer model may not be that useful for modelling real-world networks.