You've completely missed my points and at the same time gave a perfect example of someone who's rigedly trying to follow the OSI model.

> IP operates at layer 3. Layer 3, by definition, implies routing.

Layer 3 does not imply routing! I can shut down my internet link and still use a layer 3 protocol to talk to my file server from my workstation. No routing is happening because the packets are not leaving my network.

> > Their definition of routing or switching is whether it's done in software or hardware.

> No. No, it's not.

I know it's not. That's what the hardware manufactures are saying on their websites. It's stupid but it shows how blurry the line is between switching and routing.

> I think that, in general, you kinda sorta know what you're talking about (although you've got a few things incorrect) but the way you keep screwing up basic terminology really makes me wonder.

I know exactly what I'm talking about and know my terminology. The problem is you're trapped in the OSI model and can't see where things overlap.

> In networking, router, switch, frame, and packet are all clearly defined -- as are the various layers and the PDUs involved at each of them -- and mean specific things but you can call 'em whatever you want to, I suppose.

Routing and switching are not as clearly defined as you think. Just google routing vs switching and you get many variations. Some talk about frames and packets, others about MACs and IPs, but the core principle common to them all is that switching is in network and routing is out of network. A few also mention that routing is a more specific form of switching.

Your issue is you mistakenly belive that routing and switching are each tied to a specific layer in the OSI model. With that belief, yeah, frames are switched and packets are routed. But as I and others here have stated, things in the real world don't always follow the theoretical model.

Take for example the idea seen frequently online of doing away with the ethernet layer and having IP as the frame format. So now in the OSI model what was in layer 3 and 4 now become 2 and 3. Or does some of it drop and some stay in the same spot? It quickly turns into a mess. Mainly because what was supposed to happen in layer 2 (flow control and acknowlegements) is happening in layer 4 (TCP). Mainly because the designers of TCP did not follow the OSI model.

My point is that you can't use what was defined in the OSI model to rigedly define what's happening in real world protocols.

As I said, you can create a switch that operates at layer 3. It would learn what nodes are on each port by watching ARP requests. It would send out ARP replies for nodes on other ports with its own MAC and would also have to forward DHCP requests.

This device would function exactly as a switch. You could have the same subnet on many ports and it would work. You can move a node from one port to another and it would work. A router can't do those things. A router forwards packets based on their destination network.

But if you can't understand that and are stuck in the OSI model, we've esentially taken what was at layer 3 and put it in layer 2. The old layer 2 is just there for comatibility. You could even rip out one of the ethernet links between two of these layer 3 switches and replace it with a serial link that just transmits IP packets and everything would work as normal.